Actual source code: mpiaij.c

  1: #include <../src/mat/impls/aij/mpi/mpiaij.h>
  2: #include <petsc/private/vecimpl.h>
  3: #include <petsc/private/sfimpl.h>
  4: #include <petsc/private/isimpl.h>
  5: #include <petscblaslapack.h>
  6: #include <petscsf.h>
  7: #include <petsc/private/hashmapi.h>

  9: PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
 10: {
 11:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

 13:   PetscFunctionBegin;
 14:   PetscCall(PetscLogObjectState((PetscObject)mat, "Rows=%" PetscInt_FMT ", Cols=%" PetscInt_FMT, mat->rmap->N, mat->cmap->N));
 15:   PetscCall(MatStashDestroy_Private(&mat->stash));
 16:   PetscCall(VecDestroy(&aij->diag));
 17:   PetscCall(MatDestroy(&aij->A));
 18:   PetscCall(MatDestroy(&aij->B));
 19: #if defined(PETSC_USE_CTABLE)
 20:   PetscCall(PetscHMapIDestroy(&aij->colmap));
 21: #else
 22:   PetscCall(PetscFree(aij->colmap));
 23: #endif
 24:   PetscCall(PetscFree(aij->garray));
 25:   PetscCall(VecDestroy(&aij->lvec));
 26:   PetscCall(VecScatterDestroy(&aij->Mvctx));
 27:   PetscCall(PetscFree2(aij->rowvalues, aij->rowindices));
 28:   PetscCall(PetscFree(aij->ld));

 30:   PetscCall(PetscFree(mat->data));

 32:   /* may be created by MatCreateMPIAIJSumSeqAIJSymbolic */
 33:   PetscCall(PetscObjectCompose((PetscObject)mat, "MatMergeSeqsToMPI", NULL));

 35:   PetscCall(PetscObjectChangeTypeName((PetscObject)mat, NULL));
 36:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatStoreValues_C", NULL));
 37:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatRetrieveValues_C", NULL));
 38:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatIsTranspose_C", NULL));
 39:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocation_C", NULL));
 40:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetPreallocation_C", NULL));
 41:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocationCSR_C", NULL));
 42:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatDiagonalScaleLocal_C", NULL));
 43:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpibaij_C", NULL));
 44:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisbaij_C", NULL));
 45: #if defined(PETSC_HAVE_CUDA)
 46:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcusparse_C", NULL));
 47: #endif
 48: #if defined(PETSC_HAVE_HIP)
 49:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijhipsparse_C", NULL));
 50: #endif
 51: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
 52:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijkokkos_C", NULL));
 53: #endif
 54:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpidense_C", NULL));
 55: #if defined(PETSC_HAVE_ELEMENTAL)
 56:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_elemental_C", NULL));
 57: #endif
 58: #if defined(PETSC_HAVE_SCALAPACK)
 59:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_scalapack_C", NULL));
 60: #endif
 61: #if defined(PETSC_HAVE_HYPRE)
 62:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_hypre_C", NULL));
 63:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", NULL));
 64: #endif
 65:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 66:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_is_mpiaij_C", NULL));
 67:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_mpiaij_mpiaij_C", NULL));
 68:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetUseScalableIncreaseOverlap_C", NULL));
 69:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijperm_C", NULL));
 70:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijsell_C", NULL));
 71: #if defined(PETSC_HAVE_MKL_SPARSE)
 72:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijmkl_C", NULL));
 73: #endif
 74:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcrl_C", NULL));
 75:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 76:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisell_C", NULL));
 77:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetPreallocationCOO_C", NULL));
 78:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetValuesCOO_C", NULL));
 79:   PetscFunctionReturn(PETSC_SUCCESS);
 80: }

 82: /* defines MatSetValues_MPI_Hash(), MatAssemblyBegin_MPI_Hash(), and  MatAssemblyEnd_MPI_Hash() */
 83: #define TYPE AIJ
 84: #define TYPE_AIJ
 85: #include "../src/mat/impls/aij/mpi/mpihashmat.h"
 86: #undef TYPE
 87: #undef TYPE_AIJ

 89: static PetscErrorCode MatGetRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
 90: {
 91:   Mat B;

 93:   PetscFunctionBegin;
 94:   PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, &B));
 95:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject)B));
 96:   PetscCall(MatGetRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
 97:   PetscCall(MatDestroy(&B));
 98:   PetscFunctionReturn(PETSC_SUCCESS);
 99: }

101: static PetscErrorCode MatRestoreRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
102: {
103:   Mat B;

105:   PetscFunctionBegin;
106:   PetscCall(PetscObjectQuery((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject *)&B));
107:   PetscCall(MatRestoreRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
108:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", NULL));
109:   PetscFunctionReturn(PETSC_SUCCESS);
110: }

112: /*MC
113:    MATAIJ - MATAIJ = "aij" - A matrix type to be used for sparse matrices.

115:    This matrix type is identical to` MATSEQAIJ` when constructed with a single process communicator,
116:    and `MATMPIAIJ` otherwise.  As a result, for single process communicators,
117:   `MatSeqAIJSetPreallocation()` is supported, and similarly `MatMPIAIJSetPreallocation()` is supported
118:   for communicators controlling multiple processes.  It is recommended that you call both of
119:   the above preallocation routines for simplicity.

121:    Options Database Key:
122: . -mat_type aij - sets the matrix type to `MATAIJ` during a call to `MatSetFromOptions()`

124:   Developer Note:
125:   Level: beginner

127:     Subclasses include `MATAIJCUSPARSE`, `MATAIJPERM`, `MATAIJSELL`, `MATAIJMKL`, `MATAIJCRL`, `MATAIJKOKKOS`,and also automatically switches over to use inodes when
128:    enough exist.

130: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateAIJ()`, `MatCreateSeqAIJ()`, `MATSEQAIJ`, `MATMPIAIJ`
131: M*/

133: /*MC
134:    MATAIJCRL - MATAIJCRL = "aijcrl" - A matrix type to be used for sparse matrices.

136:    This matrix type is identical to `MATSEQAIJCRL` when constructed with a single process communicator,
137:    and `MATMPIAIJCRL` otherwise.  As a result, for single process communicators,
138:    `MatSeqAIJSetPreallocation()` is supported, and similarly `MatMPIAIJSetPreallocation()` is supported
139:   for communicators controlling multiple processes.  It is recommended that you call both of
140:   the above preallocation routines for simplicity.

142:    Options Database Key:
143: . -mat_type aijcrl - sets the matrix type to `MATMPIAIJCRL` during a call to `MatSetFromOptions()`

145:   Level: beginner

147: .seealso: [](ch_matrices), `Mat`, `MatCreateMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`
148: M*/

150: static PetscErrorCode MatBindToCPU_MPIAIJ(Mat A, PetscBool flg)
151: {
152:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

154:   PetscFunctionBegin;
155: #if defined(PETSC_HAVE_CUDA) || defined(PETSC_HAVE_HIP) || defined(PETSC_HAVE_VIENNACL)
156:   A->boundtocpu = flg;
157: #endif
158:   if (a->A) PetscCall(MatBindToCPU(a->A, flg));
159:   if (a->B) PetscCall(MatBindToCPU(a->B, flg));

161:   /* In addition to binding the diagonal and off-diagonal matrices, bind the local vectors used for matrix-vector products.
162:    * This maybe seems a little odd for a MatBindToCPU() call to do, but it makes no sense for the binding of these vectors
163:    * to differ from the parent matrix. */
164:   if (a->lvec) PetscCall(VecBindToCPU(a->lvec, flg));
165:   if (a->diag) PetscCall(VecBindToCPU(a->diag, flg));
166:   PetscFunctionReturn(PETSC_SUCCESS);
167: }

169: static PetscErrorCode MatSetBlockSizes_MPIAIJ(Mat M, PetscInt rbs, PetscInt cbs)
170: {
171:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)M->data;

173:   PetscFunctionBegin;
174:   if (mat->A) {
175:     PetscCall(MatSetBlockSizes(mat->A, rbs, cbs));
176:     PetscCall(MatSetBlockSizes(mat->B, rbs, 1));
177:   }
178:   PetscFunctionReturn(PETSC_SUCCESS);
179: }

181: static PetscErrorCode MatFindNonzeroRows_MPIAIJ(Mat M, IS *keptrows)
182: {
183:   Mat_MPIAIJ      *mat = (Mat_MPIAIJ *)M->data;
184:   Mat_SeqAIJ      *a   = (Mat_SeqAIJ *)mat->A->data;
185:   Mat_SeqAIJ      *b   = (Mat_SeqAIJ *)mat->B->data;
186:   const PetscInt  *ia, *ib;
187:   const MatScalar *aa, *bb, *aav, *bav;
188:   PetscInt         na, nb, i, j, *rows, cnt = 0, n0rows;
189:   PetscInt         m = M->rmap->n, rstart = M->rmap->rstart;

191:   PetscFunctionBegin;
192:   *keptrows = NULL;

194:   ia = a->i;
195:   ib = b->i;
196:   PetscCall(MatSeqAIJGetArrayRead(mat->A, &aav));
197:   PetscCall(MatSeqAIJGetArrayRead(mat->B, &bav));
198:   for (i = 0; i < m; i++) {
199:     na = ia[i + 1] - ia[i];
200:     nb = ib[i + 1] - ib[i];
201:     if (!na && !nb) {
202:       cnt++;
203:       goto ok1;
204:     }
205:     aa = aav + ia[i];
206:     for (j = 0; j < na; j++) {
207:       if (aa[j] != 0.0) goto ok1;
208:     }
209:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
210:     for (j = 0; j < nb; j++) {
211:       if (bb[j] != 0.0) goto ok1;
212:     }
213:     cnt++;
214:   ok1:;
215:   }
216:   PetscCall(MPIU_Allreduce(&cnt, &n0rows, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)M)));
217:   if (!n0rows) {
218:     PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
219:     PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
220:     PetscFunctionReturn(PETSC_SUCCESS);
221:   }
222:   PetscCall(PetscMalloc1(M->rmap->n - cnt, &rows));
223:   cnt = 0;
224:   for (i = 0; i < m; i++) {
225:     na = ia[i + 1] - ia[i];
226:     nb = ib[i + 1] - ib[i];
227:     if (!na && !nb) continue;
228:     aa = aav + ia[i];
229:     for (j = 0; j < na; j++) {
230:       if (aa[j] != 0.0) {
231:         rows[cnt++] = rstart + i;
232:         goto ok2;
233:       }
234:     }
235:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
236:     for (j = 0; j < nb; j++) {
237:       if (bb[j] != 0.0) {
238:         rows[cnt++] = rstart + i;
239:         goto ok2;
240:       }
241:     }
242:   ok2:;
243:   }
244:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), cnt, rows, PETSC_OWN_POINTER, keptrows));
245:   PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
246:   PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
247:   PetscFunctionReturn(PETSC_SUCCESS);
248: }

250: static PetscErrorCode MatDiagonalSet_MPIAIJ(Mat Y, Vec D, InsertMode is)
251: {
252:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)Y->data;
253:   PetscBool   cong;

255:   PetscFunctionBegin;
256:   PetscCall(MatHasCongruentLayouts(Y, &cong));
257:   if (Y->assembled && cong) {
258:     PetscCall(MatDiagonalSet(aij->A, D, is));
259:   } else {
260:     PetscCall(MatDiagonalSet_Default(Y, D, is));
261:   }
262:   PetscFunctionReturn(PETSC_SUCCESS);
263: }

265: static PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M, IS *zrows)
266: {
267:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)M->data;
268:   PetscInt    i, rstart, nrows, *rows;

270:   PetscFunctionBegin;
271:   *zrows = NULL;
272:   PetscCall(MatFindZeroDiagonals_SeqAIJ_Private(aij->A, &nrows, &rows));
273:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));
274:   for (i = 0; i < nrows; i++) rows[i] += rstart;
275:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), nrows, rows, PETSC_OWN_POINTER, zrows));
276:   PetscFunctionReturn(PETSC_SUCCESS);
277: }

279: static PetscErrorCode MatGetColumnReductions_MPIAIJ(Mat A, PetscInt type, PetscReal *reductions)
280: {
281:   Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)A->data;
282:   PetscInt           i, m, n, *garray = aij->garray;
283:   Mat_SeqAIJ        *a_aij = (Mat_SeqAIJ *)aij->A->data;
284:   Mat_SeqAIJ        *b_aij = (Mat_SeqAIJ *)aij->B->data;
285:   PetscReal         *work;
286:   const PetscScalar *dummy;

288:   PetscFunctionBegin;
289:   PetscCall(MatGetSize(A, &m, &n));
290:   PetscCall(PetscCalloc1(n, &work));
291:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &dummy));
292:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &dummy));
293:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &dummy));
294:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &dummy));
295:   if (type == NORM_2) {
296:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i] * a_aij->a[i]);
297:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i] * b_aij->a[i]);
298:   } else if (type == NORM_1) {
299:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
300:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
301:   } else if (type == NORM_INFINITY) {
302:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), work[A->cmap->rstart + a_aij->j[i]]);
303:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]), work[garray[b_aij->j[i]]]);
304:   } else if (type == REDUCTION_SUM_REALPART || type == REDUCTION_MEAN_REALPART) {
305:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscRealPart(a_aij->a[i]);
306:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscRealPart(b_aij->a[i]);
307:   } else if (type == REDUCTION_SUM_IMAGINARYPART || type == REDUCTION_MEAN_IMAGINARYPART) {
308:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscImaginaryPart(a_aij->a[i]);
309:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscImaginaryPart(b_aij->a[i]);
310:   } else SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONG, "Unknown reduction type");
311:   if (type == NORM_INFINITY) {
312:     PetscCall(MPIU_Allreduce(work, reductions, n, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)A)));
313:   } else {
314:     PetscCall(MPIU_Allreduce(work, reductions, n, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)A)));
315:   }
316:   PetscCall(PetscFree(work));
317:   if (type == NORM_2) {
318:     for (i = 0; i < n; i++) reductions[i] = PetscSqrtReal(reductions[i]);
319:   } else if (type == REDUCTION_MEAN_REALPART || type == REDUCTION_MEAN_IMAGINARYPART) {
320:     for (i = 0; i < n; i++) reductions[i] /= m;
321:   }
322:   PetscFunctionReturn(PETSC_SUCCESS);
323: }

325: static PetscErrorCode MatFindOffBlockDiagonalEntries_MPIAIJ(Mat A, IS *is)
326: {
327:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
328:   IS              sis, gis;
329:   const PetscInt *isis, *igis;
330:   PetscInt        n, *iis, nsis, ngis, rstart, i;

332:   PetscFunctionBegin;
333:   PetscCall(MatFindOffBlockDiagonalEntries(a->A, &sis));
334:   PetscCall(MatFindNonzeroRows(a->B, &gis));
335:   PetscCall(ISGetSize(gis, &ngis));
336:   PetscCall(ISGetSize(sis, &nsis));
337:   PetscCall(ISGetIndices(sis, &isis));
338:   PetscCall(ISGetIndices(gis, &igis));

340:   PetscCall(PetscMalloc1(ngis + nsis, &iis));
341:   PetscCall(PetscArraycpy(iis, igis, ngis));
342:   PetscCall(PetscArraycpy(iis + ngis, isis, nsis));
343:   n = ngis + nsis;
344:   PetscCall(PetscSortRemoveDupsInt(&n, iis));
345:   PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
346:   for (i = 0; i < n; i++) iis[i] += rstart;
347:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), n, iis, PETSC_OWN_POINTER, is));

349:   PetscCall(ISRestoreIndices(sis, &isis));
350:   PetscCall(ISRestoreIndices(gis, &igis));
351:   PetscCall(ISDestroy(&sis));
352:   PetscCall(ISDestroy(&gis));
353:   PetscFunctionReturn(PETSC_SUCCESS);
354: }

356: /*
357:   Local utility routine that creates a mapping from the global column
358: number to the local number in the off-diagonal part of the local
359: storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
360: a slightly higher hash table cost; without it it is not scalable (each processor
361: has an order N integer array but is fast to access.
362: */
363: PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
364: {
365:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
366:   PetscInt    n   = aij->B->cmap->n, i;

368:   PetscFunctionBegin;
369:   PetscCheck(!n || aij->garray, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MPIAIJ Matrix was assembled but is missing garray");
370: #if defined(PETSC_USE_CTABLE)
371:   PetscCall(PetscHMapICreateWithSize(n, &aij->colmap));
372:   for (i = 0; i < n; i++) PetscCall(PetscHMapISet(aij->colmap, aij->garray[i] + 1, i + 1));
373: #else
374:   PetscCall(PetscCalloc1(mat->cmap->N + 1, &aij->colmap));
375:   for (i = 0; i < n; i++) aij->colmap[aij->garray[i]] = i + 1;
376: #endif
377:   PetscFunctionReturn(PETSC_SUCCESS);
378: }

380: #define MatSetValues_SeqAIJ_A_Private(row, col, value, addv, orow, ocol) \
381:   do { \
382:     if (col <= lastcol1) low1 = 0; \
383:     else high1 = nrow1; \
384:     lastcol1 = col; \
385:     while (high1 - low1 > 5) { \
386:       t = (low1 + high1) / 2; \
387:       if (rp1[t] > col) high1 = t; \
388:       else low1 = t; \
389:     } \
390:     for (_i = low1; _i < high1; _i++) { \
391:       if (rp1[_i] > col) break; \
392:       if (rp1[_i] == col) { \
393:         if (addv == ADD_VALUES) { \
394:           ap1[_i] += value; \
395:           /* Not sure LogFlops will slow dow the code or not */ \
396:           (void)PetscLogFlops(1.0); \
397:         } else ap1[_i] = value; \
398:         goto a_noinsert; \
399:       } \
400:     } \
401:     if (value == 0.0 && ignorezeroentries && row != col) { \
402:       low1  = 0; \
403:       high1 = nrow1; \
404:       goto a_noinsert; \
405:     } \
406:     if (nonew == 1) { \
407:       low1  = 0; \
408:       high1 = nrow1; \
409:       goto a_noinsert; \
410:     } \
411:     PetscCheck(nonew != -1, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", orow, ocol); \
412:     MatSeqXAIJReallocateAIJ(A, am, 1, nrow1, row, col, rmax1, aa, ai, aj, rp1, ap1, aimax, nonew, MatScalar); \
413:     N = nrow1++ - 1; \
414:     a->nz++; \
415:     high1++; \
416:     /* shift up all the later entries in this row */ \
417:     PetscCall(PetscArraymove(rp1 + _i + 1, rp1 + _i, N - _i + 1)); \
418:     PetscCall(PetscArraymove(ap1 + _i + 1, ap1 + _i, N - _i + 1)); \
419:     rp1[_i] = col; \
420:     ap1[_i] = value; \
421:   a_noinsert:; \
422:     ailen[row] = nrow1; \
423:   } while (0)

425: #define MatSetValues_SeqAIJ_B_Private(row, col, value, addv, orow, ocol) \
426:   do { \
427:     if (col <= lastcol2) low2 = 0; \
428:     else high2 = nrow2; \
429:     lastcol2 = col; \
430:     while (high2 - low2 > 5) { \
431:       t = (low2 + high2) / 2; \
432:       if (rp2[t] > col) high2 = t; \
433:       else low2 = t; \
434:     } \
435:     for (_i = low2; _i < high2; _i++) { \
436:       if (rp2[_i] > col) break; \
437:       if (rp2[_i] == col) { \
438:         if (addv == ADD_VALUES) { \
439:           ap2[_i] += value; \
440:           (void)PetscLogFlops(1.0); \
441:         } else ap2[_i] = value; \
442:         goto b_noinsert; \
443:       } \
444:     } \
445:     if (value == 0.0 && ignorezeroentries) { \
446:       low2  = 0; \
447:       high2 = nrow2; \
448:       goto b_noinsert; \
449:     } \
450:     if (nonew == 1) { \
451:       low2  = 0; \
452:       high2 = nrow2; \
453:       goto b_noinsert; \
454:     } \
455:     PetscCheck(nonew != -1, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", orow, ocol); \
456:     MatSeqXAIJReallocateAIJ(B, bm, 1, nrow2, row, col, rmax2, ba, bi, bj, rp2, ap2, bimax, nonew, MatScalar); \
457:     N = nrow2++ - 1; \
458:     b->nz++; \
459:     high2++; \
460:     /* shift up all the later entries in this row */ \
461:     PetscCall(PetscArraymove(rp2 + _i + 1, rp2 + _i, N - _i + 1)); \
462:     PetscCall(PetscArraymove(ap2 + _i + 1, ap2 + _i, N - _i + 1)); \
463:     rp2[_i] = col; \
464:     ap2[_i] = value; \
465:   b_noinsert:; \
466:     bilen[row] = nrow2; \
467:   } while (0)

469: static PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A, PetscInt row, const PetscScalar v[])
470: {
471:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)A->data;
472:   Mat_SeqAIJ  *a = (Mat_SeqAIJ *)mat->A->data, *b = (Mat_SeqAIJ *)mat->B->data;
473:   PetscInt     l, *garray                         = mat->garray, diag;
474:   PetscScalar *aa, *ba;

476:   PetscFunctionBegin;
477:   /* code only works for square matrices A */

479:   /* find size of row to the left of the diagonal part */
480:   PetscCall(MatGetOwnershipRange(A, &diag, NULL));
481:   row = row - diag;
482:   for (l = 0; l < b->i[row + 1] - b->i[row]; l++) {
483:     if (garray[b->j[b->i[row] + l]] > diag) break;
484:   }
485:   if (l) {
486:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
487:     PetscCall(PetscArraycpy(ba + b->i[row], v, l));
488:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
489:   }

491:   /* diagonal part */
492:   if (a->i[row + 1] - a->i[row]) {
493:     PetscCall(MatSeqAIJGetArray(mat->A, &aa));
494:     PetscCall(PetscArraycpy(aa + a->i[row], v + l, (a->i[row + 1] - a->i[row])));
495:     PetscCall(MatSeqAIJRestoreArray(mat->A, &aa));
496:   }

498:   /* right of diagonal part */
499:   if (b->i[row + 1] - b->i[row] - l) {
500:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
501:     PetscCall(PetscArraycpy(ba + b->i[row] + l, v + l + a->i[row + 1] - a->i[row], b->i[row + 1] - b->i[row] - l));
502:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
503:   }
504:   PetscFunctionReturn(PETSC_SUCCESS);
505: }

507: PetscErrorCode MatSetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt im[], PetscInt n, const PetscInt in[], const PetscScalar v[], InsertMode addv)
508: {
509:   Mat_MPIAIJ *aij   = (Mat_MPIAIJ *)mat->data;
510:   PetscScalar value = 0.0;
511:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
512:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
513:   PetscBool   roworiented = aij->roworiented;

515:   /* Some Variables required in the macro */
516:   Mat         A     = aij->A;
517:   Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
518:   PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
519:   PetscBool   ignorezeroentries = a->ignorezeroentries;
520:   Mat         B                 = aij->B;
521:   Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
522:   PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
523:   MatScalar  *aa, *ba;
524:   PetscInt   *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
525:   PetscInt    nonew;
526:   MatScalar  *ap1, *ap2;

528:   PetscFunctionBegin;
529:   PetscCall(MatSeqAIJGetArray(A, &aa));
530:   PetscCall(MatSeqAIJGetArray(B, &ba));
531:   for (i = 0; i < m; i++) {
532:     if (im[i] < 0) continue;
533:     PetscCheck(im[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, im[i], mat->rmap->N - 1);
534:     if (im[i] >= rstart && im[i] < rend) {
535:       row      = im[i] - rstart;
536:       lastcol1 = -1;
537:       rp1      = PetscSafePointerPlusOffset(aj, ai[row]);
538:       ap1      = PetscSafePointerPlusOffset(aa, ai[row]);
539:       rmax1    = aimax[row];
540:       nrow1    = ailen[row];
541:       low1     = 0;
542:       high1    = nrow1;
543:       lastcol2 = -1;
544:       rp2      = PetscSafePointerPlusOffset(bj, bi[row]);
545:       ap2      = PetscSafePointerPlusOffset(ba, bi[row]);
546:       rmax2    = bimax[row];
547:       nrow2    = bilen[row];
548:       low2     = 0;
549:       high2    = nrow2;

551:       for (j = 0; j < n; j++) {
552:         if (v) value = roworiented ? v[i * n + j] : v[i + j * m];
553:         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
554:         if (in[j] >= cstart && in[j] < cend) {
555:           col   = in[j] - cstart;
556:           nonew = a->nonew;
557:           MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
558:         } else if (in[j] < 0) {
559:           continue;
560:         } else {
561:           PetscCheck(in[j] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
562:           if (mat->was_assembled) {
563:             if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
564: #if defined(PETSC_USE_CTABLE)
565:             PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col)); /* map global col ids to local ones */
566:             col--;
567: #else
568:             col = aij->colmap[in[j]] - 1;
569: #endif
570:             if (col < 0 && !((Mat_SeqAIJ *)aij->B->data)->nonew) { /* col < 0 means in[j] is a new col for B */
571:               PetscCall(MatDisAssemble_MPIAIJ(mat));               /* Change aij->B from reduced/local format to expanded/global format */
572:               col = in[j];
573:               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
574:               B     = aij->B;
575:               b     = (Mat_SeqAIJ *)B->data;
576:               bimax = b->imax;
577:               bi    = b->i;
578:               bilen = b->ilen;
579:               bj    = b->j;
580:               ba    = b->a;
581:               rp2   = bj + bi[row];
582:               ap2   = ba + bi[row];
583:               rmax2 = bimax[row];
584:               nrow2 = bilen[row];
585:               low2  = 0;
586:               high2 = nrow2;
587:               bm    = aij->B->rmap->n;
588:               ba    = b->a;
589:             } else if (col < 0 && !(ignorezeroentries && value == 0.0)) {
590:               if (1 == ((Mat_SeqAIJ *)aij->B->data)->nonew) {
591:                 PetscCall(PetscInfo(mat, "Skipping of insertion of new nonzero location in off-diagonal portion of matrix %g(%" PetscInt_FMT ",%" PetscInt_FMT ")\n", (double)PetscRealPart(value), im[i], in[j]));
592:               } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", im[i], in[j]);
593:             }
594:           } else col = in[j];
595:           nonew = b->nonew;
596:           MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
597:         }
598:       }
599:     } else {
600:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Setting off process row %" PetscInt_FMT " even though MatSetOption(,MAT_NO_OFF_PROC_ENTRIES,PETSC_TRUE) was set", im[i]);
601:       if (!aij->donotstash) {
602:         mat->assembled = PETSC_FALSE;
603:         if (roworiented) {
604:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i * n), (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
605:         } else {
606:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i), m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
607:         }
608:       }
609:     }
610:   }
611:   PetscCall(MatSeqAIJRestoreArray(A, &aa)); /* aa, bb might have been free'd due to reallocation above. But we don't access them here */
612:   PetscCall(MatSeqAIJRestoreArray(B, &ba));
613:   PetscFunctionReturn(PETSC_SUCCESS);
614: }

616: /*
617:     This function sets the j and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
618:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
619:     No off-processor parts off the matrix are allowed here and mat->was_assembled has to be PETSC_FALSE.
620: */
621: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat_Symbolic(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[])
622: {
623:   Mat_MPIAIJ *aij    = (Mat_MPIAIJ *)mat->data;
624:   Mat         A      = aij->A; /* diagonal part of the matrix */
625:   Mat         B      = aij->B; /* off-diagonal part of the matrix */
626:   Mat_SeqAIJ *a      = (Mat_SeqAIJ *)A->data;
627:   Mat_SeqAIJ *b      = (Mat_SeqAIJ *)B->data;
628:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, col;
629:   PetscInt   *ailen = a->ilen, *aj = a->j;
630:   PetscInt   *bilen = b->ilen, *bj = b->j;
631:   PetscInt    am          = aij->A->rmap->n, j;
632:   PetscInt    diag_so_far = 0, dnz;
633:   PetscInt    offd_so_far = 0, onz;

635:   PetscFunctionBegin;
636:   /* Iterate over all rows of the matrix */
637:   for (j = 0; j < am; j++) {
638:     dnz = onz = 0;
639:     /*  Iterate over all non-zero columns of the current row */
640:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
641:       /* If column is in the diagonal */
642:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
643:         aj[diag_so_far++] = mat_j[col] - cstart;
644:         dnz++;
645:       } else { /* off-diagonal entries */
646:         bj[offd_so_far++] = mat_j[col];
647:         onz++;
648:       }
649:     }
650:     ailen[j] = dnz;
651:     bilen[j] = onz;
652:   }
653:   PetscFunctionReturn(PETSC_SUCCESS);
654: }

656: /*
657:     This function sets the local j, a and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
658:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
659:     No off-processor parts off the matrix are allowed here, they are set at a later point by MatSetValues_MPIAIJ.
660:     Also, mat->was_assembled has to be false, otherwise the statement aj[rowstart_diag+dnz_row] = mat_j[col] - cstart;
661:     would not be true and the more complex MatSetValues_MPIAIJ has to be used.
662: */
663: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[], const PetscScalar mat_a[])
664: {
665:   Mat_MPIAIJ  *aij  = (Mat_MPIAIJ *)mat->data;
666:   Mat          A    = aij->A; /* diagonal part of the matrix */
667:   Mat          B    = aij->B; /* off-diagonal part of the matrix */
668:   Mat_SeqAIJ  *aijd = (Mat_SeqAIJ *)aij->A->data, *aijo = (Mat_SeqAIJ *)aij->B->data;
669:   Mat_SeqAIJ  *a      = (Mat_SeqAIJ *)A->data;
670:   Mat_SeqAIJ  *b      = (Mat_SeqAIJ *)B->data;
671:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend;
672:   PetscInt    *ailen = a->ilen, *aj = a->j;
673:   PetscInt    *bilen = b->ilen, *bj = b->j;
674:   PetscInt     am          = aij->A->rmap->n, j;
675:   PetscInt    *full_diag_i = aijd->i, *full_offd_i = aijo->i; /* These variables can also include non-local elements, which are set at a later point. */
676:   PetscInt     col, dnz_row, onz_row, rowstart_diag, rowstart_offd;
677:   PetscScalar *aa = a->a, *ba = b->a;

679:   PetscFunctionBegin;
680:   /* Iterate over all rows of the matrix */
681:   for (j = 0; j < am; j++) {
682:     dnz_row = onz_row = 0;
683:     rowstart_offd     = full_offd_i[j];
684:     rowstart_diag     = full_diag_i[j];
685:     /*  Iterate over all non-zero columns of the current row */
686:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
687:       /* If column is in the diagonal */
688:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
689:         aj[rowstart_diag + dnz_row] = mat_j[col] - cstart;
690:         aa[rowstart_diag + dnz_row] = mat_a[col];
691:         dnz_row++;
692:       } else { /* off-diagonal entries */
693:         bj[rowstart_offd + onz_row] = mat_j[col];
694:         ba[rowstart_offd + onz_row] = mat_a[col];
695:         onz_row++;
696:       }
697:     }
698:     ailen[j] = dnz_row;
699:     bilen[j] = onz_row;
700:   }
701:   PetscFunctionReturn(PETSC_SUCCESS);
702: }

704: static PetscErrorCode MatGetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt idxm[], PetscInt n, const PetscInt idxn[], PetscScalar v[])
705: {
706:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
707:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
708:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;

710:   PetscFunctionBegin;
711:   for (i = 0; i < m; i++) {
712:     if (idxm[i] < 0) continue; /* negative row */
713:     PetscCheck(idxm[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, idxm[i], mat->rmap->N - 1);
714:     PetscCheck(idxm[i] >= rstart && idxm[i] < rend, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only local values currently supported, row requested %" PetscInt_FMT " range [%" PetscInt_FMT " %" PetscInt_FMT ")", idxm[i], rstart, rend);
715:     row = idxm[i] - rstart;
716:     for (j = 0; j < n; j++) {
717:       if (idxn[j] < 0) continue; /* negative column */
718:       PetscCheck(idxn[j] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, idxn[j], mat->cmap->N - 1);
719:       if (idxn[j] >= cstart && idxn[j] < cend) {
720:         col = idxn[j] - cstart;
721:         PetscCall(MatGetValues(aij->A, 1, &row, 1, &col, v + i * n + j));
722:       } else {
723:         if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
724: #if defined(PETSC_USE_CTABLE)
725:         PetscCall(PetscHMapIGetWithDefault(aij->colmap, idxn[j] + 1, 0, &col));
726:         col--;
727: #else
728:         col = aij->colmap[idxn[j]] - 1;
729: #endif
730:         if ((col < 0) || (aij->garray[col] != idxn[j])) *(v + i * n + j) = 0.0;
731:         else PetscCall(MatGetValues(aij->B, 1, &row, 1, &col, v + i * n + j));
732:       }
733:     }
734:   }
735:   PetscFunctionReturn(PETSC_SUCCESS);
736: }

738: static PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat, MatAssemblyType mode)
739: {
740:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
741:   PetscInt    nstash, reallocs;

743:   PetscFunctionBegin;
744:   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(PETSC_SUCCESS);

746:   PetscCall(MatStashScatterBegin_Private(mat, &mat->stash, mat->rmap->range));
747:   PetscCall(MatStashGetInfo_Private(&mat->stash, &nstash, &reallocs));
748:   PetscCall(PetscInfo(aij->A, "Stash has %" PetscInt_FMT " entries, uses %" PetscInt_FMT " mallocs.\n", nstash, reallocs));
749:   PetscFunctionReturn(PETSC_SUCCESS);
750: }

752: PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat, MatAssemblyType mode)
753: {
754:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
755:   PetscMPIInt  n;
756:   PetscInt     i, j, rstart, ncols, flg;
757:   PetscInt    *row, *col;
758:   PetscBool    other_disassembled;
759:   PetscScalar *val;

761:   /* do not use 'b = (Mat_SeqAIJ*)aij->B->data' as B can be reset in disassembly */

763:   PetscFunctionBegin;
764:   if (!aij->donotstash && !mat->nooffprocentries) {
765:     while (1) {
766:       PetscCall(MatStashScatterGetMesg_Private(&mat->stash, &n, &row, &col, &val, &flg));
767:       if (!flg) break;

769:       for (i = 0; i < n;) {
770:         /* Now identify the consecutive vals belonging to the same row */
771:         for (j = i, rstart = row[j]; j < n; j++) {
772:           if (row[j] != rstart) break;
773:         }
774:         if (j < n) ncols = j - i;
775:         else ncols = n - i;
776:         /* Now assemble all these values with a single function call */
777:         PetscCall(MatSetValues_MPIAIJ(mat, 1, row + i, ncols, col + i, val + i, mat->insertmode));
778:         i = j;
779:       }
780:     }
781:     PetscCall(MatStashScatterEnd_Private(&mat->stash));
782:   }
783: #if defined(PETSC_HAVE_DEVICE)
784:   if (mat->offloadmask == PETSC_OFFLOAD_CPU) aij->A->offloadmask = PETSC_OFFLOAD_CPU;
785:   /* We call MatBindToCPU() on aij->A and aij->B here, because if MatBindToCPU_MPIAIJ() is called before assembly, it cannot bind these. */
786:   if (mat->boundtocpu) {
787:     PetscCall(MatBindToCPU(aij->A, PETSC_TRUE));
788:     PetscCall(MatBindToCPU(aij->B, PETSC_TRUE));
789:   }
790: #endif
791:   PetscCall(MatAssemblyBegin(aij->A, mode));
792:   PetscCall(MatAssemblyEnd(aij->A, mode));

794:   /* determine if any processor has disassembled, if so we must
795:      also disassemble ourself, in order that we may reassemble. */
796:   /*
797:      if nonzero structure of submatrix B cannot change then we know that
798:      no processor disassembled thus we can skip this stuff
799:   */
800:   if (!((Mat_SeqAIJ *)aij->B->data)->nonew) {
801:     PetscCall(MPIU_Allreduce(&mat->was_assembled, &other_disassembled, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
802:     if (mat->was_assembled && !other_disassembled) { /* mat on this rank has reduced off-diag B with local col ids, but globally it does not */
803:       PetscCall(MatDisAssemble_MPIAIJ(mat));
804:     }
805:   }
806:   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) PetscCall(MatSetUpMultiply_MPIAIJ(mat));
807:   PetscCall(MatSetOption(aij->B, MAT_USE_INODES, PETSC_FALSE));
808: #if defined(PETSC_HAVE_DEVICE)
809:   if (mat->offloadmask == PETSC_OFFLOAD_CPU && aij->B->offloadmask != PETSC_OFFLOAD_UNALLOCATED) aij->B->offloadmask = PETSC_OFFLOAD_CPU;
810: #endif
811:   PetscCall(MatAssemblyBegin(aij->B, mode));
812:   PetscCall(MatAssemblyEnd(aij->B, mode));

814:   PetscCall(PetscFree2(aij->rowvalues, aij->rowindices));

816:   aij->rowvalues = NULL;

818:   PetscCall(VecDestroy(&aij->diag));

820:   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
821:   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ *)aij->A->data)->nonew) {
822:     PetscObjectState state = aij->A->nonzerostate + aij->B->nonzerostate;
823:     PetscCall(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));
824:   }
825: #if defined(PETSC_HAVE_DEVICE)
826:   mat->offloadmask = PETSC_OFFLOAD_BOTH;
827: #endif
828:   PetscFunctionReturn(PETSC_SUCCESS);
829: }

831: static PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
832: {
833:   Mat_MPIAIJ *l = (Mat_MPIAIJ *)A->data;

835:   PetscFunctionBegin;
836:   PetscCall(MatZeroEntries(l->A));
837:   PetscCall(MatZeroEntries(l->B));
838:   PetscFunctionReturn(PETSC_SUCCESS);
839: }

841: static PetscErrorCode MatZeroRows_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
842: {
843:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)A->data;
844:   PetscInt   *lrows;
845:   PetscInt    r, len;
846:   PetscBool   cong;

848:   PetscFunctionBegin;
849:   /* get locally owned rows */
850:   PetscCall(MatZeroRowsMapLocal_Private(A, N, rows, &len, &lrows));
851:   PetscCall(MatHasCongruentLayouts(A, &cong));
852:   /* fix right-hand side if needed */
853:   if (x && b) {
854:     const PetscScalar *xx;
855:     PetscScalar       *bb;

857:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
858:     PetscCall(VecGetArrayRead(x, &xx));
859:     PetscCall(VecGetArray(b, &bb));
860:     for (r = 0; r < len; ++r) bb[lrows[r]] = diag * xx[lrows[r]];
861:     PetscCall(VecRestoreArrayRead(x, &xx));
862:     PetscCall(VecRestoreArray(b, &bb));
863:   }

865:   if (diag != 0.0 && cong) {
866:     PetscCall(MatZeroRows(mat->A, len, lrows, diag, NULL, NULL));
867:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
868:   } else if (diag != 0.0) { /* non-square or non congruent layouts -> if keepnonzeropattern is false, we allow for new insertion */
869:     Mat_SeqAIJ *aijA = (Mat_SeqAIJ *)mat->A->data;
870:     Mat_SeqAIJ *aijB = (Mat_SeqAIJ *)mat->B->data;
871:     PetscInt    nnwA, nnwB;
872:     PetscBool   nnzA, nnzB;

874:     nnwA = aijA->nonew;
875:     nnwB = aijB->nonew;
876:     nnzA = aijA->keepnonzeropattern;
877:     nnzB = aijB->keepnonzeropattern;
878:     if (!nnzA) {
879:       PetscCall(PetscInfo(mat->A, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on diagonal block.\n"));
880:       aijA->nonew = 0;
881:     }
882:     if (!nnzB) {
883:       PetscCall(PetscInfo(mat->B, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on off-diagonal block.\n"));
884:       aijB->nonew = 0;
885:     }
886:     /* Must zero here before the next loop */
887:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
888:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
889:     for (r = 0; r < len; ++r) {
890:       const PetscInt row = lrows[r] + A->rmap->rstart;
891:       if (row >= A->cmap->N) continue;
892:       PetscCall(MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES));
893:     }
894:     aijA->nonew = nnwA;
895:     aijB->nonew = nnwB;
896:   } else {
897:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
898:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
899:   }
900:   PetscCall(PetscFree(lrows));
901:   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
902:   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

904:   /* only change matrix nonzero state if pattern was allowed to be changed */
905:   if (!((Mat_SeqAIJ *)mat->A->data)->keepnonzeropattern || !((Mat_SeqAIJ *)mat->A->data)->nonew) {
906:     PetscObjectState state = mat->A->nonzerostate + mat->B->nonzerostate;
907:     PetscCall(MPIU_Allreduce(&state, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
908:   }
909:   PetscFunctionReturn(PETSC_SUCCESS);
910: }

912: static PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
913: {
914:   Mat_MPIAIJ        *l = (Mat_MPIAIJ *)A->data;
915:   PetscMPIInt        n = A->rmap->n;
916:   PetscInt           i, j, r, m, len = 0;
917:   PetscInt          *lrows, *owners = A->rmap->range;
918:   PetscMPIInt        p = 0;
919:   PetscSFNode       *rrows;
920:   PetscSF            sf;
921:   const PetscScalar *xx;
922:   PetscScalar       *bb, *mask, *aij_a;
923:   Vec                xmask, lmask;
924:   Mat_SeqAIJ        *aij = (Mat_SeqAIJ *)l->B->data;
925:   const PetscInt    *aj, *ii, *ridx;
926:   PetscScalar       *aa;

928:   PetscFunctionBegin;
929:   /* Create SF where leaves are input rows and roots are owned rows */
930:   PetscCall(PetscMalloc1(n, &lrows));
931:   for (r = 0; r < n; ++r) lrows[r] = -1;
932:   PetscCall(PetscMalloc1(N, &rrows));
933:   for (r = 0; r < N; ++r) {
934:     const PetscInt idx = rows[r];
935:     PetscCheck(idx >= 0 && A->rmap->N > idx, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row %" PetscInt_FMT " out of range [0,%" PetscInt_FMT ")", idx, A->rmap->N);
936:     if (idx < owners[p] || owners[p + 1] <= idx) { /* short-circuit the search if the last p owns this row too */
937:       PetscCall(PetscLayoutFindOwner(A->rmap, idx, &p));
938:     }
939:     rrows[r].rank  = p;
940:     rrows[r].index = rows[r] - owners[p];
941:   }
942:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
943:   PetscCall(PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER));
944:   /* Collect flags for rows to be zeroed */
945:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
946:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
947:   PetscCall(PetscSFDestroy(&sf));
948:   /* Compress and put in row numbers */
949:   for (r = 0; r < n; ++r)
950:     if (lrows[r] >= 0) lrows[len++] = r;
951:   /* zero diagonal part of matrix */
952:   PetscCall(MatZeroRowsColumns(l->A, len, lrows, diag, x, b));
953:   /* handle off-diagonal part of matrix */
954:   PetscCall(MatCreateVecs(A, &xmask, NULL));
955:   PetscCall(VecDuplicate(l->lvec, &lmask));
956:   PetscCall(VecGetArray(xmask, &bb));
957:   for (i = 0; i < len; i++) bb[lrows[i]] = 1;
958:   PetscCall(VecRestoreArray(xmask, &bb));
959:   PetscCall(VecScatterBegin(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
960:   PetscCall(VecScatterEnd(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
961:   PetscCall(VecDestroy(&xmask));
962:   if (x && b) { /* this code is buggy when the row and column layout don't match */
963:     PetscBool cong;

965:     PetscCall(MatHasCongruentLayouts(A, &cong));
966:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
967:     PetscCall(VecScatterBegin(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
968:     PetscCall(VecScatterEnd(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
969:     PetscCall(VecGetArrayRead(l->lvec, &xx));
970:     PetscCall(VecGetArray(b, &bb));
971:   }
972:   PetscCall(VecGetArray(lmask, &mask));
973:   /* remove zeroed rows of off-diagonal matrix */
974:   PetscCall(MatSeqAIJGetArray(l->B, &aij_a));
975:   ii = aij->i;
976:   for (i = 0; i < len; i++) PetscCall(PetscArrayzero(PetscSafePointerPlusOffset(aij_a, ii[lrows[i]]), ii[lrows[i] + 1] - ii[lrows[i]]));
977:   /* loop over all elements of off process part of matrix zeroing removed columns*/
978:   if (aij->compressedrow.use) {
979:     m    = aij->compressedrow.nrows;
980:     ii   = aij->compressedrow.i;
981:     ridx = aij->compressedrow.rindex;
982:     for (i = 0; i < m; i++) {
983:       n  = ii[i + 1] - ii[i];
984:       aj = aij->j + ii[i];
985:       aa = aij_a + ii[i];

987:       for (j = 0; j < n; j++) {
988:         if (PetscAbsScalar(mask[*aj])) {
989:           if (b) bb[*ridx] -= *aa * xx[*aj];
990:           *aa = 0.0;
991:         }
992:         aa++;
993:         aj++;
994:       }
995:       ridx++;
996:     }
997:   } else { /* do not use compressed row format */
998:     m = l->B->rmap->n;
999:     for (i = 0; i < m; i++) {
1000:       n  = ii[i + 1] - ii[i];
1001:       aj = aij->j + ii[i];
1002:       aa = aij_a + ii[i];
1003:       for (j = 0; j < n; j++) {
1004:         if (PetscAbsScalar(mask[*aj])) {
1005:           if (b) bb[i] -= *aa * xx[*aj];
1006:           *aa = 0.0;
1007:         }
1008:         aa++;
1009:         aj++;
1010:       }
1011:     }
1012:   }
1013:   if (x && b) {
1014:     PetscCall(VecRestoreArray(b, &bb));
1015:     PetscCall(VecRestoreArrayRead(l->lvec, &xx));
1016:   }
1017:   PetscCall(MatSeqAIJRestoreArray(l->B, &aij_a));
1018:   PetscCall(VecRestoreArray(lmask, &mask));
1019:   PetscCall(VecDestroy(&lmask));
1020:   PetscCall(PetscFree(lrows));

1022:   /* only change matrix nonzero state if pattern was allowed to be changed */
1023:   if (!((Mat_SeqAIJ *)l->A->data)->nonew) {
1024:     PetscObjectState state = l->A->nonzerostate + l->B->nonzerostate;
1025:     PetscCall(MPIU_Allreduce(&state, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
1026:   }
1027:   PetscFunctionReturn(PETSC_SUCCESS);
1028: }

1030: static PetscErrorCode MatMult_MPIAIJ(Mat A, Vec xx, Vec yy)
1031: {
1032:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
1033:   PetscInt    nt;
1034:   VecScatter  Mvctx = a->Mvctx;

1036:   PetscFunctionBegin;
1037:   PetscCall(VecGetLocalSize(xx, &nt));
1038:   PetscCheck(nt == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Incompatible partition of A (%" PetscInt_FMT ") and xx (%" PetscInt_FMT ")", A->cmap->n, nt);
1039:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1040:   PetscUseTypeMethod(a->A, mult, xx, yy);
1041:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1042:   PetscUseTypeMethod(a->B, multadd, a->lvec, yy, yy);
1043:   PetscFunctionReturn(PETSC_SUCCESS);
1044: }

1046: static PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A, Vec bb, Vec xx)
1047: {
1048:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1050:   PetscFunctionBegin;
1051:   PetscCall(MatMultDiagonalBlock(a->A, bb, xx));
1052:   PetscFunctionReturn(PETSC_SUCCESS);
1053: }

1055: static PetscErrorCode MatMultAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1056: {
1057:   Mat_MPIAIJ *a     = (Mat_MPIAIJ *)A->data;
1058:   VecScatter  Mvctx = a->Mvctx;

1060:   PetscFunctionBegin;
1061:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1062:   PetscCall((*a->A->ops->multadd)(a->A, xx, yy, zz));
1063:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1064:   PetscCall((*a->B->ops->multadd)(a->B, a->lvec, zz, zz));
1065:   PetscFunctionReturn(PETSC_SUCCESS);
1066: }

1068: static PetscErrorCode MatMultTranspose_MPIAIJ(Mat A, Vec xx, Vec yy)
1069: {
1070:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1072:   PetscFunctionBegin;
1073:   /* do nondiagonal part */
1074:   PetscCall((*a->B->ops->multtranspose)(a->B, xx, a->lvec));
1075:   /* do local part */
1076:   PetscCall((*a->A->ops->multtranspose)(a->A, xx, yy));
1077:   /* add partial results together */
1078:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1079:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1080:   PetscFunctionReturn(PETSC_SUCCESS);
1081: }

1083: static PetscErrorCode MatIsTranspose_MPIAIJ(Mat Amat, Mat Bmat, PetscReal tol, PetscBool *f)
1084: {
1085:   MPI_Comm    comm;
1086:   Mat_MPIAIJ *Aij = (Mat_MPIAIJ *)Amat->data, *Bij = (Mat_MPIAIJ *)Bmat->data;
1087:   Mat         Adia = Aij->A, Bdia = Bij->A, Aoff, Boff, *Aoffs, *Boffs;
1088:   IS          Me, Notme;
1089:   PetscInt    M, N, first, last, *notme, i;
1090:   PetscBool   lf;
1091:   PetscMPIInt size;

1093:   PetscFunctionBegin;
1094:   /* Easy test: symmetric diagonal block */
1095:   PetscCall(MatIsTranspose(Adia, Bdia, tol, &lf));
1096:   PetscCall(MPIU_Allreduce(&lf, f, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)Amat)));
1097:   if (!*f) PetscFunctionReturn(PETSC_SUCCESS);
1098:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
1099:   PetscCallMPI(MPI_Comm_size(comm, &size));
1100:   if (size == 1) PetscFunctionReturn(PETSC_SUCCESS);

1102:   /* Hard test: off-diagonal block. This takes a MatCreateSubMatrix. */
1103:   PetscCall(MatGetSize(Amat, &M, &N));
1104:   PetscCall(MatGetOwnershipRange(Amat, &first, &last));
1105:   PetscCall(PetscMalloc1(N - last + first, &notme));
1106:   for (i = 0; i < first; i++) notme[i] = i;
1107:   for (i = last; i < M; i++) notme[i - last + first] = i;
1108:   PetscCall(ISCreateGeneral(MPI_COMM_SELF, N - last + first, notme, PETSC_COPY_VALUES, &Notme));
1109:   PetscCall(ISCreateStride(MPI_COMM_SELF, last - first, first, 1, &Me));
1110:   PetscCall(MatCreateSubMatrices(Amat, 1, &Me, &Notme, MAT_INITIAL_MATRIX, &Aoffs));
1111:   Aoff = Aoffs[0];
1112:   PetscCall(MatCreateSubMatrices(Bmat, 1, &Notme, &Me, MAT_INITIAL_MATRIX, &Boffs));
1113:   Boff = Boffs[0];
1114:   PetscCall(MatIsTranspose(Aoff, Boff, tol, f));
1115:   PetscCall(MatDestroyMatrices(1, &Aoffs));
1116:   PetscCall(MatDestroyMatrices(1, &Boffs));
1117:   PetscCall(ISDestroy(&Me));
1118:   PetscCall(ISDestroy(&Notme));
1119:   PetscCall(PetscFree(notme));
1120:   PetscFunctionReturn(PETSC_SUCCESS);
1121: }

1123: static PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1124: {
1125:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1127:   PetscFunctionBegin;
1128:   /* do nondiagonal part */
1129:   PetscCall((*a->B->ops->multtranspose)(a->B, xx, a->lvec));
1130:   /* do local part */
1131:   PetscCall((*a->A->ops->multtransposeadd)(a->A, xx, yy, zz));
1132:   /* add partial results together */
1133:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1134:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1135:   PetscFunctionReturn(PETSC_SUCCESS);
1136: }

1138: /*
1139:   This only works correctly for square matrices where the subblock A->A is the
1140:    diagonal block
1141: */
1142: static PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A, Vec v)
1143: {
1144:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1146:   PetscFunctionBegin;
1147:   PetscCheck(A->rmap->N == A->cmap->N, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Supports only square matrix where A->A is diag block");
1148:   PetscCheck(A->rmap->rstart == A->cmap->rstart && A->rmap->rend == A->cmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "row partition must equal col partition");
1149:   PetscCall(MatGetDiagonal(a->A, v));
1150:   PetscFunctionReturn(PETSC_SUCCESS);
1151: }

1153: static PetscErrorCode MatScale_MPIAIJ(Mat A, PetscScalar aa)
1154: {
1155:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1157:   PetscFunctionBegin;
1158:   PetscCall(MatScale(a->A, aa));
1159:   PetscCall(MatScale(a->B, aa));
1160:   PetscFunctionReturn(PETSC_SUCCESS);
1161: }

1163: static PetscErrorCode MatView_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
1164: {
1165:   Mat_MPIAIJ        *aij    = (Mat_MPIAIJ *)mat->data;
1166:   Mat_SeqAIJ        *A      = (Mat_SeqAIJ *)aij->A->data;
1167:   Mat_SeqAIJ        *B      = (Mat_SeqAIJ *)aij->B->data;
1168:   const PetscInt    *garray = aij->garray;
1169:   const PetscScalar *aa, *ba;
1170:   PetscInt           header[4], M, N, m, rs, cs, cnt, i, ja, jb;
1171:   PetscInt64         nz, hnz;
1172:   PetscInt          *rowlens;
1173:   PetscInt          *colidxs;
1174:   PetscScalar       *matvals;
1175:   PetscMPIInt        rank;

1177:   PetscFunctionBegin;
1178:   PetscCall(PetscViewerSetUp(viewer));

1180:   M  = mat->rmap->N;
1181:   N  = mat->cmap->N;
1182:   m  = mat->rmap->n;
1183:   rs = mat->rmap->rstart;
1184:   cs = mat->cmap->rstart;
1185:   nz = A->nz + B->nz;

1187:   /* write matrix header */
1188:   header[0] = MAT_FILE_CLASSID;
1189:   header[1] = M;
1190:   header[2] = N;
1191:   PetscCallMPI(MPI_Reduce(&nz, &hnz, 1, MPIU_INT64, MPI_SUM, 0, PetscObjectComm((PetscObject)mat)));
1192:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1193:   if (rank == 0) {
1194:     if (hnz > PETSC_MAX_INT) header[3] = PETSC_MAX_INT;
1195:     else header[3] = (PetscInt)hnz;
1196:   }
1197:   PetscCall(PetscViewerBinaryWrite(viewer, header, 4, PETSC_INT));

1199:   /* fill in and store row lengths  */
1200:   PetscCall(PetscMalloc1(m, &rowlens));
1201:   for (i = 0; i < m; i++) rowlens[i] = A->i[i + 1] - A->i[i] + B->i[i + 1] - B->i[i];
1202:   PetscCall(PetscViewerBinaryWriteAll(viewer, rowlens, m, rs, M, PETSC_INT));
1203:   PetscCall(PetscFree(rowlens));

1205:   /* fill in and store column indices */
1206:   PetscCall(PetscMalloc1(nz, &colidxs));
1207:   for (cnt = 0, i = 0; i < m; i++) {
1208:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1209:       if (garray[B->j[jb]] > cs) break;
1210:       colidxs[cnt++] = garray[B->j[jb]];
1211:     }
1212:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) colidxs[cnt++] = A->j[ja] + cs;
1213:     for (; jb < B->i[i + 1]; jb++) colidxs[cnt++] = garray[B->j[jb]];
1214:   }
1215:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1216:   PetscCall(PetscViewerBinaryWriteAll(viewer, colidxs, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
1217:   PetscCall(PetscFree(colidxs));

1219:   /* fill in and store nonzero values */
1220:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &aa));
1221:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &ba));
1222:   PetscCall(PetscMalloc1(nz, &matvals));
1223:   for (cnt = 0, i = 0; i < m; i++) {
1224:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1225:       if (garray[B->j[jb]] > cs) break;
1226:       matvals[cnt++] = ba[jb];
1227:     }
1228:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) matvals[cnt++] = aa[ja];
1229:     for (; jb < B->i[i + 1]; jb++) matvals[cnt++] = ba[jb];
1230:   }
1231:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &aa));
1232:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &ba));
1233:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_LIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1234:   PetscCall(PetscViewerBinaryWriteAll(viewer, matvals, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
1235:   PetscCall(PetscFree(matvals));

1237:   /* write block size option to the viewer's .info file */
1238:   PetscCall(MatView_Binary_BlockSizes(mat, viewer));
1239:   PetscFunctionReturn(PETSC_SUCCESS);
1240: }

1242: #include <petscdraw.h>
1243: static PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat, PetscViewer viewer)
1244: {
1245:   Mat_MPIAIJ       *aij  = (Mat_MPIAIJ *)mat->data;
1246:   PetscMPIInt       rank = aij->rank, size = aij->size;
1247:   PetscBool         isdraw, iascii, isbinary;
1248:   PetscViewer       sviewer;
1249:   PetscViewerFormat format;

1251:   PetscFunctionBegin;
1252:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1253:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
1254:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1255:   if (iascii) {
1256:     PetscCall(PetscViewerGetFormat(viewer, &format));
1257:     if (format == PETSC_VIEWER_LOAD_BALANCE) {
1258:       PetscInt i, nmax = 0, nmin = PETSC_MAX_INT, navg = 0, *nz, nzlocal = ((Mat_SeqAIJ *)aij->A->data)->nz + ((Mat_SeqAIJ *)aij->B->data)->nz;
1259:       PetscCall(PetscMalloc1(size, &nz));
1260:       PetscCallMPI(MPI_Allgather(&nzlocal, 1, MPIU_INT, nz, 1, MPIU_INT, PetscObjectComm((PetscObject)mat)));
1261:       for (i = 0; i < (PetscInt)size; i++) {
1262:         nmax = PetscMax(nmax, nz[i]);
1263:         nmin = PetscMin(nmin, nz[i]);
1264:         navg += nz[i];
1265:       }
1266:       PetscCall(PetscFree(nz));
1267:       navg = navg / size;
1268:       PetscCall(PetscViewerASCIIPrintf(viewer, "Load Balance - Nonzeros: Min %" PetscInt_FMT "  avg %" PetscInt_FMT "  max %" PetscInt_FMT "\n", nmin, navg, nmax));
1269:       PetscFunctionReturn(PETSC_SUCCESS);
1270:     }
1271:     PetscCall(PetscViewerGetFormat(viewer, &format));
1272:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1273:       MatInfo   info;
1274:       PetscInt *inodes = NULL;

1276:       PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1277:       PetscCall(MatGetInfo(mat, MAT_LOCAL, &info));
1278:       PetscCall(MatInodeGetInodeSizes(aij->A, NULL, &inodes, NULL));
1279:       PetscCall(PetscViewerASCIIPushSynchronized(viewer));
1280:       if (!inodes) {
1281:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] Local rows %" PetscInt_FMT " nz %" PetscInt_FMT " nz alloced %" PetscInt_FMT " mem %g, not using I-node routines\n", rank, mat->rmap->n, (PetscInt)info.nz_used, (PetscInt)info.nz_allocated,
1282:                                                      (double)info.memory));
1283:       } else {
1284:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] Local rows %" PetscInt_FMT " nz %" PetscInt_FMT " nz alloced %" PetscInt_FMT " mem %g, using I-node routines\n", rank, mat->rmap->n, (PetscInt)info.nz_used, (PetscInt)info.nz_allocated,
1285:                                                      (double)info.memory));
1286:       }
1287:       PetscCall(MatGetInfo(aij->A, MAT_LOCAL, &info));
1288:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] on-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1289:       PetscCall(MatGetInfo(aij->B, MAT_LOCAL, &info));
1290:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] off-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1291:       PetscCall(PetscViewerFlush(viewer));
1292:       PetscCall(PetscViewerASCIIPopSynchronized(viewer));
1293:       PetscCall(PetscViewerASCIIPrintf(viewer, "Information on VecScatter used in matrix-vector product: \n"));
1294:       PetscCall(VecScatterView(aij->Mvctx, viewer));
1295:       PetscFunctionReturn(PETSC_SUCCESS);
1296:     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1297:       PetscInt inodecount, inodelimit, *inodes;
1298:       PetscCall(MatInodeGetInodeSizes(aij->A, &inodecount, &inodes, &inodelimit));
1299:       if (inodes) {
1300:         PetscCall(PetscViewerASCIIPrintf(viewer, "using I-node (on process 0) routines: found %" PetscInt_FMT " nodes, limit used is %" PetscInt_FMT "\n", inodecount, inodelimit));
1301:       } else {
1302:         PetscCall(PetscViewerASCIIPrintf(viewer, "not using I-node (on process 0) routines\n"));
1303:       }
1304:       PetscFunctionReturn(PETSC_SUCCESS);
1305:     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1306:       PetscFunctionReturn(PETSC_SUCCESS);
1307:     }
1308:   } else if (isbinary) {
1309:     if (size == 1) {
1310:       PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1311:       PetscCall(MatView(aij->A, viewer));
1312:     } else {
1313:       PetscCall(MatView_MPIAIJ_Binary(mat, viewer));
1314:     }
1315:     PetscFunctionReturn(PETSC_SUCCESS);
1316:   } else if (iascii && size == 1) {
1317:     PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1318:     PetscCall(MatView(aij->A, viewer));
1319:     PetscFunctionReturn(PETSC_SUCCESS);
1320:   } else if (isdraw) {
1321:     PetscDraw draw;
1322:     PetscBool isnull;
1323:     PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
1324:     PetscCall(PetscDrawIsNull(draw, &isnull));
1325:     if (isnull) PetscFunctionReturn(PETSC_SUCCESS);
1326:   }

1328:   { /* assemble the entire matrix onto first processor */
1329:     Mat A = NULL, Av;
1330:     IS  isrow, iscol;

1332:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->rmap->N : 0, 0, 1, &isrow));
1333:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->cmap->N : 0, 0, 1, &iscol));
1334:     PetscCall(MatCreateSubMatrix(mat, isrow, iscol, MAT_INITIAL_MATRIX, &A));
1335:     PetscCall(MatMPIAIJGetSeqAIJ(A, &Av, NULL, NULL));
1336:     /*  The commented code uses MatCreateSubMatrices instead */
1337:     /*
1338:     Mat *AA, A = NULL, Av;
1339:     IS  isrow,iscol;

1341:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->rmap->N : 0,0,1,&isrow));
1342:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->cmap->N : 0,0,1,&iscol));
1343:     PetscCall(MatCreateSubMatrices(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&AA));
1344:     if (rank == 0) {
1345:        PetscCall(PetscObjectReference((PetscObject)AA[0]));
1346:        A    = AA[0];
1347:        Av   = AA[0];
1348:     }
1349:     PetscCall(MatDestroySubMatrices(1,&AA));
1350: */
1351:     PetscCall(ISDestroy(&iscol));
1352:     PetscCall(ISDestroy(&isrow));
1353:     /*
1354:        Everyone has to call to draw the matrix since the graphics waits are
1355:        synchronized across all processors that share the PetscDraw object
1356:     */
1357:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1358:     if (rank == 0) {
1359:       if (((PetscObject)mat)->name) PetscCall(PetscObjectSetName((PetscObject)Av, ((PetscObject)mat)->name));
1360:       PetscCall(MatView_SeqAIJ(Av, sviewer));
1361:     }
1362:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1363:     PetscCall(MatDestroy(&A));
1364:   }
1365:   PetscFunctionReturn(PETSC_SUCCESS);
1366: }

1368: PetscErrorCode MatView_MPIAIJ(Mat mat, PetscViewer viewer)
1369: {
1370:   PetscBool iascii, isdraw, issocket, isbinary;

1372:   PetscFunctionBegin;
1373:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
1374:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1375:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1376:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSOCKET, &issocket));
1377:   if (iascii || isdraw || isbinary || issocket) PetscCall(MatView_MPIAIJ_ASCIIorDraworSocket(mat, viewer));
1378:   PetscFunctionReturn(PETSC_SUCCESS);
1379: }

1381: static PetscErrorCode MatSOR_MPIAIJ(Mat matin, Vec bb, PetscReal omega, MatSORType flag, PetscReal fshift, PetscInt its, PetscInt lits, Vec xx)
1382: {
1383:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)matin->data;
1384:   Vec         bb1 = NULL;
1385:   PetscBool   hasop;

1387:   PetscFunctionBegin;
1388:   if (flag == SOR_APPLY_UPPER) {
1389:     PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1390:     PetscFunctionReturn(PETSC_SUCCESS);
1391:   }

1393:   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) PetscCall(VecDuplicate(bb, &bb1));

1395:   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1396:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1397:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1398:       its--;
1399:     }

1401:     while (its--) {
1402:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1403:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1405:       /* update rhs: bb1 = bb - B*x */
1406:       PetscCall(VecScale(mat->lvec, -1.0));
1407:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1409:       /* local sweep */
1410:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_SYMMETRIC_SWEEP, fshift, lits, 1, xx));
1411:     }
1412:   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1413:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1414:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1415:       its--;
1416:     }
1417:     while (its--) {
1418:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1419:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1421:       /* update rhs: bb1 = bb - B*x */
1422:       PetscCall(VecScale(mat->lvec, -1.0));
1423:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1425:       /* local sweep */
1426:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_FORWARD_SWEEP, fshift, lits, 1, xx));
1427:     }
1428:   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1429:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1430:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1431:       its--;
1432:     }
1433:     while (its--) {
1434:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1435:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1437:       /* update rhs: bb1 = bb - B*x */
1438:       PetscCall(VecScale(mat->lvec, -1.0));
1439:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1441:       /* local sweep */
1442:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_BACKWARD_SWEEP, fshift, lits, 1, xx));
1443:     }
1444:   } else if (flag & SOR_EISENSTAT) {
1445:     Vec xx1;

1447:     PetscCall(VecDuplicate(bb, &xx1));
1448:     PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP), fshift, lits, 1, xx));

1450:     PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1451:     PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1452:     if (!mat->diag) {
1453:       PetscCall(MatCreateVecs(matin, &mat->diag, NULL));
1454:       PetscCall(MatGetDiagonal(matin, mat->diag));
1455:     }
1456:     PetscCall(MatHasOperation(matin, MATOP_MULT_DIAGONAL_BLOCK, &hasop));
1457:     if (hasop) {
1458:       PetscCall(MatMultDiagonalBlock(matin, xx, bb1));
1459:     } else {
1460:       PetscCall(VecPointwiseMult(bb1, mat->diag, xx));
1461:     }
1462:     PetscCall(VecAYPX(bb1, (omega - 2.0) / omega, bb));

1464:     PetscCall(MatMultAdd(mat->B, mat->lvec, bb1, bb1));

1466:     /* local sweep */
1467:     PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP), fshift, lits, 1, xx1));
1468:     PetscCall(VecAXPY(xx, 1.0, xx1));
1469:     PetscCall(VecDestroy(&xx1));
1470:   } else SETERRQ(PetscObjectComm((PetscObject)matin), PETSC_ERR_SUP, "Parallel SOR not supported");

1472:   PetscCall(VecDestroy(&bb1));

1474:   matin->factorerrortype = mat->A->factorerrortype;
1475:   PetscFunctionReturn(PETSC_SUCCESS);
1476: }

1478: static PetscErrorCode MatPermute_MPIAIJ(Mat A, IS rowp, IS colp, Mat *B)
1479: {
1480:   Mat             aA, aB, Aperm;
1481:   const PetscInt *rwant, *cwant, *gcols, *ai, *bi, *aj, *bj;
1482:   PetscScalar    *aa, *ba;
1483:   PetscInt        i, j, m, n, ng, anz, bnz, *dnnz, *onnz, *tdnnz, *tonnz, *rdest, *cdest, *work, *gcdest;
1484:   PetscSF         rowsf, sf;
1485:   IS              parcolp = NULL;
1486:   PetscBool       done;

1488:   PetscFunctionBegin;
1489:   PetscCall(MatGetLocalSize(A, &m, &n));
1490:   PetscCall(ISGetIndices(rowp, &rwant));
1491:   PetscCall(ISGetIndices(colp, &cwant));
1492:   PetscCall(PetscMalloc3(PetscMax(m, n), &work, m, &rdest, n, &cdest));

1494:   /* Invert row permutation to find out where my rows should go */
1495:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &rowsf));
1496:   PetscCall(PetscSFSetGraphLayout(rowsf, A->rmap, A->rmap->n, NULL, PETSC_OWN_POINTER, rwant));
1497:   PetscCall(PetscSFSetFromOptions(rowsf));
1498:   for (i = 0; i < m; i++) work[i] = A->rmap->rstart + i;
1499:   PetscCall(PetscSFReduceBegin(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));
1500:   PetscCall(PetscSFReduceEnd(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));

1502:   /* Invert column permutation to find out where my columns should go */
1503:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1504:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, A->cmap->n, NULL, PETSC_OWN_POINTER, cwant));
1505:   PetscCall(PetscSFSetFromOptions(sf));
1506:   for (i = 0; i < n; i++) work[i] = A->cmap->rstart + i;
1507:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1508:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1509:   PetscCall(PetscSFDestroy(&sf));

1511:   PetscCall(ISRestoreIndices(rowp, &rwant));
1512:   PetscCall(ISRestoreIndices(colp, &cwant));
1513:   PetscCall(MatMPIAIJGetSeqAIJ(A, &aA, &aB, &gcols));

1515:   /* Find out where my gcols should go */
1516:   PetscCall(MatGetSize(aB, NULL, &ng));
1517:   PetscCall(PetscMalloc1(ng, &gcdest));
1518:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1519:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, ng, NULL, PETSC_OWN_POINTER, gcols));
1520:   PetscCall(PetscSFSetFromOptions(sf));
1521:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1522:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1523:   PetscCall(PetscSFDestroy(&sf));

1525:   PetscCall(PetscCalloc4(m, &dnnz, m, &onnz, m, &tdnnz, m, &tonnz));
1526:   PetscCall(MatGetRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1527:   PetscCall(MatGetRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1528:   for (i = 0; i < m; i++) {
1529:     PetscInt    row = rdest[i];
1530:     PetscMPIInt rowner;
1531:     PetscCall(PetscLayoutFindOwner(A->rmap, row, &rowner));
1532:     for (j = ai[i]; j < ai[i + 1]; j++) {
1533:       PetscInt    col = cdest[aj[j]];
1534:       PetscMPIInt cowner;
1535:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner)); /* Could build an index for the columns to eliminate this search */
1536:       if (rowner == cowner) dnnz[i]++;
1537:       else onnz[i]++;
1538:     }
1539:     for (j = bi[i]; j < bi[i + 1]; j++) {
1540:       PetscInt    col = gcdest[bj[j]];
1541:       PetscMPIInt cowner;
1542:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner));
1543:       if (rowner == cowner) dnnz[i]++;
1544:       else onnz[i]++;
1545:     }
1546:   }
1547:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1548:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1549:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1550:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1551:   PetscCall(PetscSFDestroy(&rowsf));

1553:   PetscCall(MatCreateAIJ(PetscObjectComm((PetscObject)A), A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N, 0, tdnnz, 0, tonnz, &Aperm));
1554:   PetscCall(MatSeqAIJGetArray(aA, &aa));
1555:   PetscCall(MatSeqAIJGetArray(aB, &ba));
1556:   for (i = 0; i < m; i++) {
1557:     PetscInt *acols = dnnz, *bcols = onnz; /* Repurpose now-unneeded arrays */
1558:     PetscInt  j0, rowlen;
1559:     rowlen = ai[i + 1] - ai[i];
1560:     for (j0 = j = 0; j < rowlen; j0 = j) { /* rowlen could be larger than number of rows m, so sum in batches */
1561:       for (; j < PetscMin(rowlen, j0 + m); j++) acols[j - j0] = cdest[aj[ai[i] + j]];
1562:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, acols, aa + ai[i] + j0, INSERT_VALUES));
1563:     }
1564:     rowlen = bi[i + 1] - bi[i];
1565:     for (j0 = j = 0; j < rowlen; j0 = j) {
1566:       for (; j < PetscMin(rowlen, j0 + m); j++) bcols[j - j0] = gcdest[bj[bi[i] + j]];
1567:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, bcols, ba + bi[i] + j0, INSERT_VALUES));
1568:     }
1569:   }
1570:   PetscCall(MatAssemblyBegin(Aperm, MAT_FINAL_ASSEMBLY));
1571:   PetscCall(MatAssemblyEnd(Aperm, MAT_FINAL_ASSEMBLY));
1572:   PetscCall(MatRestoreRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1573:   PetscCall(MatRestoreRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1574:   PetscCall(MatSeqAIJRestoreArray(aA, &aa));
1575:   PetscCall(MatSeqAIJRestoreArray(aB, &ba));
1576:   PetscCall(PetscFree4(dnnz, onnz, tdnnz, tonnz));
1577:   PetscCall(PetscFree3(work, rdest, cdest));
1578:   PetscCall(PetscFree(gcdest));
1579:   if (parcolp) PetscCall(ISDestroy(&colp));
1580:   *B = Aperm;
1581:   PetscFunctionReturn(PETSC_SUCCESS);
1582: }

1584: static PetscErrorCode MatGetGhosts_MPIAIJ(Mat mat, PetscInt *nghosts, const PetscInt *ghosts[])
1585: {
1586:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1588:   PetscFunctionBegin;
1589:   PetscCall(MatGetSize(aij->B, NULL, nghosts));
1590:   if (ghosts) *ghosts = aij->garray;
1591:   PetscFunctionReturn(PETSC_SUCCESS);
1592: }

1594: static PetscErrorCode MatGetInfo_MPIAIJ(Mat matin, MatInfoType flag, MatInfo *info)
1595: {
1596:   Mat_MPIAIJ    *mat = (Mat_MPIAIJ *)matin->data;
1597:   Mat            A = mat->A, B = mat->B;
1598:   PetscLogDouble isend[5], irecv[5];

1600:   PetscFunctionBegin;
1601:   info->block_size = 1.0;
1602:   PetscCall(MatGetInfo(A, MAT_LOCAL, info));

1604:   isend[0] = info->nz_used;
1605:   isend[1] = info->nz_allocated;
1606:   isend[2] = info->nz_unneeded;
1607:   isend[3] = info->memory;
1608:   isend[4] = info->mallocs;

1610:   PetscCall(MatGetInfo(B, MAT_LOCAL, info));

1612:   isend[0] += info->nz_used;
1613:   isend[1] += info->nz_allocated;
1614:   isend[2] += info->nz_unneeded;
1615:   isend[3] += info->memory;
1616:   isend[4] += info->mallocs;
1617:   if (flag == MAT_LOCAL) {
1618:     info->nz_used      = isend[0];
1619:     info->nz_allocated = isend[1];
1620:     info->nz_unneeded  = isend[2];
1621:     info->memory       = isend[3];
1622:     info->mallocs      = isend[4];
1623:   } else if (flag == MAT_GLOBAL_MAX) {
1624:     PetscCall(MPIU_Allreduce(isend, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_MAX, PetscObjectComm((PetscObject)matin)));

1626:     info->nz_used      = irecv[0];
1627:     info->nz_allocated = irecv[1];
1628:     info->nz_unneeded  = irecv[2];
1629:     info->memory       = irecv[3];
1630:     info->mallocs      = irecv[4];
1631:   } else if (flag == MAT_GLOBAL_SUM) {
1632:     PetscCall(MPIU_Allreduce(isend, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_SUM, PetscObjectComm((PetscObject)matin)));

1634:     info->nz_used      = irecv[0];
1635:     info->nz_allocated = irecv[1];
1636:     info->nz_unneeded  = irecv[2];
1637:     info->memory       = irecv[3];
1638:     info->mallocs      = irecv[4];
1639:   }
1640:   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1641:   info->fill_ratio_needed = 0;
1642:   info->factor_mallocs    = 0;
1643:   PetscFunctionReturn(PETSC_SUCCESS);
1644: }

1646: PetscErrorCode MatSetOption_MPIAIJ(Mat A, MatOption op, PetscBool flg)
1647: {
1648:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1650:   PetscFunctionBegin;
1651:   switch (op) {
1652:   case MAT_NEW_NONZERO_LOCATIONS:
1653:   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1654:   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1655:   case MAT_KEEP_NONZERO_PATTERN:
1656:   case MAT_NEW_NONZERO_LOCATION_ERR:
1657:   case MAT_USE_INODES:
1658:   case MAT_IGNORE_ZERO_ENTRIES:
1659:   case MAT_FORM_EXPLICIT_TRANSPOSE:
1660:     MatCheckPreallocated(A, 1);
1661:     PetscCall(MatSetOption(a->A, op, flg));
1662:     PetscCall(MatSetOption(a->B, op, flg));
1663:     break;
1664:   case MAT_ROW_ORIENTED:
1665:     MatCheckPreallocated(A, 1);
1666:     a->roworiented = flg;

1668:     PetscCall(MatSetOption(a->A, op, flg));
1669:     PetscCall(MatSetOption(a->B, op, flg));
1670:     break;
1671:   case MAT_FORCE_DIAGONAL_ENTRIES:
1672:   case MAT_SORTED_FULL:
1673:     PetscCall(PetscInfo(A, "Option %s ignored\n", MatOptions[op]));
1674:     break;
1675:   case MAT_IGNORE_OFF_PROC_ENTRIES:
1676:     a->donotstash = flg;
1677:     break;
1678:   /* Symmetry flags are handled directly by MatSetOption() and they don't affect preallocation */
1679:   case MAT_SPD:
1680:   case MAT_SYMMETRIC:
1681:   case MAT_STRUCTURALLY_SYMMETRIC:
1682:   case MAT_HERMITIAN:
1683:   case MAT_SYMMETRY_ETERNAL:
1684:   case MAT_STRUCTURAL_SYMMETRY_ETERNAL:
1685:   case MAT_SPD_ETERNAL:
1686:     /* if the diagonal matrix is square it inherits some of the properties above */
1687:     break;
1688:   case MAT_SUBMAT_SINGLEIS:
1689:     A->submat_singleis = flg;
1690:     break;
1691:   case MAT_STRUCTURE_ONLY:
1692:     /* The option is handled directly by MatSetOption() */
1693:     break;
1694:   default:
1695:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "unknown option %d", op);
1696:   }
1697:   PetscFunctionReturn(PETSC_SUCCESS);
1698: }

1700: PetscErrorCode MatGetRow_MPIAIJ(Mat matin, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1701: {
1702:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)matin->data;
1703:   PetscScalar *vworkA, *vworkB, **pvA, **pvB, *v_p;
1704:   PetscInt     i, *cworkA, *cworkB, **pcA, **pcB, cstart = matin->cmap->rstart;
1705:   PetscInt     nztot, nzA, nzB, lrow, rstart = matin->rmap->rstart, rend = matin->rmap->rend;
1706:   PetscInt    *cmap, *idx_p;

1708:   PetscFunctionBegin;
1709:   PetscCheck(!mat->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Already active");
1710:   mat->getrowactive = PETSC_TRUE;

1712:   if (!mat->rowvalues && (idx || v)) {
1713:     /*
1714:         allocate enough space to hold information from the longest row.
1715:     */
1716:     Mat_SeqAIJ *Aa = (Mat_SeqAIJ *)mat->A->data, *Ba = (Mat_SeqAIJ *)mat->B->data;
1717:     PetscInt    max = 1, tmp;
1718:     for (i = 0; i < matin->rmap->n; i++) {
1719:       tmp = Aa->i[i + 1] - Aa->i[i] + Ba->i[i + 1] - Ba->i[i];
1720:       if (max < tmp) max = tmp;
1721:     }
1722:     PetscCall(PetscMalloc2(max, &mat->rowvalues, max, &mat->rowindices));
1723:   }

1725:   PetscCheck(row >= rstart && row < rend, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Only local rows");
1726:   lrow = row - rstart;

1728:   pvA = &vworkA;
1729:   pcA = &cworkA;
1730:   pvB = &vworkB;
1731:   pcB = &cworkB;
1732:   if (!v) {
1733:     pvA = NULL;
1734:     pvB = NULL;
1735:   }
1736:   if (!idx) {
1737:     pcA = NULL;
1738:     if (!v) pcB = NULL;
1739:   }
1740:   PetscCall((*mat->A->ops->getrow)(mat->A, lrow, &nzA, pcA, pvA));
1741:   PetscCall((*mat->B->ops->getrow)(mat->B, lrow, &nzB, pcB, pvB));
1742:   nztot = nzA + nzB;

1744:   cmap = mat->garray;
1745:   if (v || idx) {
1746:     if (nztot) {
1747:       /* Sort by increasing column numbers, assuming A and B already sorted */
1748:       PetscInt imark = -1;
1749:       if (v) {
1750:         *v = v_p = mat->rowvalues;
1751:         for (i = 0; i < nzB; i++) {
1752:           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1753:           else break;
1754:         }
1755:         imark = i;
1756:         for (i = 0; i < nzA; i++) v_p[imark + i] = vworkA[i];
1757:         for (i = imark; i < nzB; i++) v_p[nzA + i] = vworkB[i];
1758:       }
1759:       if (idx) {
1760:         *idx = idx_p = mat->rowindices;
1761:         if (imark > -1) {
1762:           for (i = 0; i < imark; i++) idx_p[i] = cmap[cworkB[i]];
1763:         } else {
1764:           for (i = 0; i < nzB; i++) {
1765:             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1766:             else break;
1767:           }
1768:           imark = i;
1769:         }
1770:         for (i = 0; i < nzA; i++) idx_p[imark + i] = cstart + cworkA[i];
1771:         for (i = imark; i < nzB; i++) idx_p[nzA + i] = cmap[cworkB[i]];
1772:       }
1773:     } else {
1774:       if (idx) *idx = NULL;
1775:       if (v) *v = NULL;
1776:     }
1777:   }
1778:   *nz = nztot;
1779:   PetscCall((*mat->A->ops->restorerow)(mat->A, lrow, &nzA, pcA, pvA));
1780:   PetscCall((*mat->B->ops->restorerow)(mat->B, lrow, &nzB, pcB, pvB));
1781:   PetscFunctionReturn(PETSC_SUCCESS);
1782: }

1784: PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1785: {
1786:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1788:   PetscFunctionBegin;
1789:   PetscCheck(aij->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "MatGetRow() must be called first");
1790:   aij->getrowactive = PETSC_FALSE;
1791:   PetscFunctionReturn(PETSC_SUCCESS);
1792: }

1794: static PetscErrorCode MatNorm_MPIAIJ(Mat mat, NormType type, PetscReal *norm)
1795: {
1796:   Mat_MPIAIJ      *aij  = (Mat_MPIAIJ *)mat->data;
1797:   Mat_SeqAIJ      *amat = (Mat_SeqAIJ *)aij->A->data, *bmat = (Mat_SeqAIJ *)aij->B->data;
1798:   PetscInt         i, j, cstart = mat->cmap->rstart;
1799:   PetscReal        sum = 0.0;
1800:   const MatScalar *v, *amata, *bmata;

1802:   PetscFunctionBegin;
1803:   if (aij->size == 1) {
1804:     PetscCall(MatNorm(aij->A, type, norm));
1805:   } else {
1806:     PetscCall(MatSeqAIJGetArrayRead(aij->A, &amata));
1807:     PetscCall(MatSeqAIJGetArrayRead(aij->B, &bmata));
1808:     if (type == NORM_FROBENIUS) {
1809:       v = amata;
1810:       for (i = 0; i < amat->nz; i++) {
1811:         sum += PetscRealPart(PetscConj(*v) * (*v));
1812:         v++;
1813:       }
1814:       v = bmata;
1815:       for (i = 0; i < bmat->nz; i++) {
1816:         sum += PetscRealPart(PetscConj(*v) * (*v));
1817:         v++;
1818:       }
1819:       PetscCall(MPIU_Allreduce(&sum, norm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1820:       *norm = PetscSqrtReal(*norm);
1821:       PetscCall(PetscLogFlops(2.0 * amat->nz + 2.0 * bmat->nz));
1822:     } else if (type == NORM_1) { /* max column norm */
1823:       PetscReal *tmp, *tmp2;
1824:       PetscInt  *jj, *garray = aij->garray;
1825:       PetscCall(PetscCalloc1(mat->cmap->N + 1, &tmp));
1826:       PetscCall(PetscMalloc1(mat->cmap->N + 1, &tmp2));
1827:       *norm = 0.0;
1828:       v     = amata;
1829:       jj    = amat->j;
1830:       for (j = 0; j < amat->nz; j++) {
1831:         tmp[cstart + *jj++] += PetscAbsScalar(*v);
1832:         v++;
1833:       }
1834:       v  = bmata;
1835:       jj = bmat->j;
1836:       for (j = 0; j < bmat->nz; j++) {
1837:         tmp[garray[*jj++]] += PetscAbsScalar(*v);
1838:         v++;
1839:       }
1840:       PetscCall(MPIU_Allreduce(tmp, tmp2, mat->cmap->N, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1841:       for (j = 0; j < mat->cmap->N; j++) {
1842:         if (tmp2[j] > *norm) *norm = tmp2[j];
1843:       }
1844:       PetscCall(PetscFree(tmp));
1845:       PetscCall(PetscFree(tmp2));
1846:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1847:     } else if (type == NORM_INFINITY) { /* max row norm */
1848:       PetscReal ntemp = 0.0;
1849:       for (j = 0; j < aij->A->rmap->n; j++) {
1850:         v   = PetscSafePointerPlusOffset(amata, amat->i[j]);
1851:         sum = 0.0;
1852:         for (i = 0; i < amat->i[j + 1] - amat->i[j]; i++) {
1853:           sum += PetscAbsScalar(*v);
1854:           v++;
1855:         }
1856:         v = PetscSafePointerPlusOffset(bmata, bmat->i[j]);
1857:         for (i = 0; i < bmat->i[j + 1] - bmat->i[j]; i++) {
1858:           sum += PetscAbsScalar(*v);
1859:           v++;
1860:         }
1861:         if (sum > ntemp) ntemp = sum;
1862:       }
1863:       PetscCall(MPIU_Allreduce(&ntemp, norm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)mat)));
1864:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1865:     } else SETERRQ(PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "No support for two norm");
1866:     PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &amata));
1867:     PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &bmata));
1868:   }
1869:   PetscFunctionReturn(PETSC_SUCCESS);
1870: }

1872: static PetscErrorCode MatTranspose_MPIAIJ(Mat A, MatReuse reuse, Mat *matout)
1873: {
1874:   Mat_MPIAIJ      *a    = (Mat_MPIAIJ *)A->data, *b;
1875:   Mat_SeqAIJ      *Aloc = (Mat_SeqAIJ *)a->A->data, *Bloc = (Mat_SeqAIJ *)a->B->data, *sub_B_diag;
1876:   PetscInt         M = A->rmap->N, N = A->cmap->N, ma, na, mb, nb, row, *cols, *cols_tmp, *B_diag_ilen, i, ncol, A_diag_ncol;
1877:   const PetscInt  *ai, *aj, *bi, *bj, *B_diag_i;
1878:   Mat              B, A_diag, *B_diag;
1879:   const MatScalar *pbv, *bv;

1881:   PetscFunctionBegin;
1882:   if (reuse == MAT_REUSE_MATRIX) PetscCall(MatTransposeCheckNonzeroState_Private(A, *matout));
1883:   ma = A->rmap->n;
1884:   na = A->cmap->n;
1885:   mb = a->B->rmap->n;
1886:   nb = a->B->cmap->n;
1887:   ai = Aloc->i;
1888:   aj = Aloc->j;
1889:   bi = Bloc->i;
1890:   bj = Bloc->j;
1891:   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1892:     PetscInt            *d_nnz, *g_nnz, *o_nnz;
1893:     PetscSFNode         *oloc;
1894:     PETSC_UNUSED PetscSF sf;

1896:     PetscCall(PetscMalloc4(na, &d_nnz, na, &o_nnz, nb, &g_nnz, nb, &oloc));
1897:     /* compute d_nnz for preallocation */
1898:     PetscCall(PetscArrayzero(d_nnz, na));
1899:     for (i = 0; i < ai[ma]; i++) d_nnz[aj[i]]++;
1900:     /* compute local off-diagonal contributions */
1901:     PetscCall(PetscArrayzero(g_nnz, nb));
1902:     for (i = 0; i < bi[ma]; i++) g_nnz[bj[i]]++;
1903:     /* map those to global */
1904:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1905:     PetscCall(PetscSFSetGraphLayout(sf, A->cmap, nb, NULL, PETSC_USE_POINTER, a->garray));
1906:     PetscCall(PetscSFSetFromOptions(sf));
1907:     PetscCall(PetscArrayzero(o_nnz, na));
1908:     PetscCall(PetscSFReduceBegin(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1909:     PetscCall(PetscSFReduceEnd(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1910:     PetscCall(PetscSFDestroy(&sf));

1912:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
1913:     PetscCall(MatSetSizes(B, A->cmap->n, A->rmap->n, N, M));
1914:     PetscCall(MatSetBlockSizes(B, PetscAbs(A->cmap->bs), PetscAbs(A->rmap->bs)));
1915:     PetscCall(MatSetType(B, ((PetscObject)A)->type_name));
1916:     PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
1917:     PetscCall(PetscFree4(d_nnz, o_nnz, g_nnz, oloc));
1918:   } else {
1919:     B = *matout;
1920:     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE));
1921:   }

1923:   b           = (Mat_MPIAIJ *)B->data;
1924:   A_diag      = a->A;
1925:   B_diag      = &b->A;
1926:   sub_B_diag  = (Mat_SeqAIJ *)(*B_diag)->data;
1927:   A_diag_ncol = A_diag->cmap->N;
1928:   B_diag_ilen = sub_B_diag->ilen;
1929:   B_diag_i    = sub_B_diag->i;

1931:   /* Set ilen for diagonal of B */
1932:   for (i = 0; i < A_diag_ncol; i++) B_diag_ilen[i] = B_diag_i[i + 1] - B_diag_i[i];

1934:   /* Transpose the diagonal part of the matrix. In contrast to the off-diagonal part, this can be done
1935:   very quickly (=without using MatSetValues), because all writes are local. */
1936:   PetscCall(MatTransposeSetPrecursor(A_diag, *B_diag));
1937:   PetscCall(MatTranspose(A_diag, MAT_REUSE_MATRIX, B_diag));

1939:   /* copy over the B part */
1940:   PetscCall(PetscMalloc1(bi[mb], &cols));
1941:   PetscCall(MatSeqAIJGetArrayRead(a->B, &bv));
1942:   pbv = bv;
1943:   row = A->rmap->rstart;
1944:   for (i = 0; i < bi[mb]; i++) cols[i] = a->garray[bj[i]];
1945:   cols_tmp = cols;
1946:   for (i = 0; i < mb; i++) {
1947:     ncol = bi[i + 1] - bi[i];
1948:     PetscCall(MatSetValues(B, ncol, cols_tmp, 1, &row, pbv, INSERT_VALUES));
1949:     row++;
1950:     if (pbv) pbv += ncol;
1951:     if (cols_tmp) cols_tmp += ncol;
1952:   }
1953:   PetscCall(PetscFree(cols));
1954:   PetscCall(MatSeqAIJRestoreArrayRead(a->B, &bv));

1956:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
1957:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
1958:   if (reuse == MAT_INITIAL_MATRIX || reuse == MAT_REUSE_MATRIX) {
1959:     *matout = B;
1960:   } else {
1961:     PetscCall(MatHeaderMerge(A, &B));
1962:   }
1963:   PetscFunctionReturn(PETSC_SUCCESS);
1964: }

1966: static PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat, Vec ll, Vec rr)
1967: {
1968:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
1969:   Mat         a = aij->A, b = aij->B;
1970:   PetscInt    s1, s2, s3;

1972:   PetscFunctionBegin;
1973:   PetscCall(MatGetLocalSize(mat, &s2, &s3));
1974:   if (rr) {
1975:     PetscCall(VecGetLocalSize(rr, &s1));
1976:     PetscCheck(s1 == s3, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "right vector non-conforming local size");
1977:     /* Overlap communication with computation. */
1978:     PetscCall(VecScatterBegin(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1979:   }
1980:   if (ll) {
1981:     PetscCall(VecGetLocalSize(ll, &s1));
1982:     PetscCheck(s1 == s2, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "left vector non-conforming local size");
1983:     PetscUseTypeMethod(b, diagonalscale, ll, NULL);
1984:   }
1985:   /* scale  the diagonal block */
1986:   PetscUseTypeMethod(a, diagonalscale, ll, rr);

1988:   if (rr) {
1989:     /* Do a scatter end and then right scale the off-diagonal block */
1990:     PetscCall(VecScatterEnd(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1991:     PetscUseTypeMethod(b, diagonalscale, NULL, aij->lvec);
1992:   }
1993:   PetscFunctionReturn(PETSC_SUCCESS);
1994: }

1996: static PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
1997: {
1998:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2000:   PetscFunctionBegin;
2001:   PetscCall(MatSetUnfactored(a->A));
2002:   PetscFunctionReturn(PETSC_SUCCESS);
2003: }

2005: static PetscErrorCode MatEqual_MPIAIJ(Mat A, Mat B, PetscBool *flag)
2006: {
2007:   Mat_MPIAIJ *matB = (Mat_MPIAIJ *)B->data, *matA = (Mat_MPIAIJ *)A->data;
2008:   Mat         a, b, c, d;
2009:   PetscBool   flg;

2011:   PetscFunctionBegin;
2012:   a = matA->A;
2013:   b = matA->B;
2014:   c = matB->A;
2015:   d = matB->B;

2017:   PetscCall(MatEqual(a, c, &flg));
2018:   if (flg) PetscCall(MatEqual(b, d, &flg));
2019:   PetscCall(MPIU_Allreduce(&flg, flag, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)A)));
2020:   PetscFunctionReturn(PETSC_SUCCESS);
2021: }

2023: static PetscErrorCode MatCopy_MPIAIJ(Mat A, Mat B, MatStructure str)
2024: {
2025:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2026:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2028:   PetscFunctionBegin;
2029:   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2030:   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2031:     /* because of the column compression in the off-processor part of the matrix a->B,
2032:        the number of columns in a->B and b->B may be different, hence we cannot call
2033:        the MatCopy() directly on the two parts. If need be, we can provide a more
2034:        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2035:        then copying the submatrices */
2036:     PetscCall(MatCopy_Basic(A, B, str));
2037:   } else {
2038:     PetscCall(MatCopy(a->A, b->A, str));
2039:     PetscCall(MatCopy(a->B, b->B, str));
2040:   }
2041:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2042:   PetscFunctionReturn(PETSC_SUCCESS);
2043: }

2045: /*
2046:    Computes the number of nonzeros per row needed for preallocation when X and Y
2047:    have different nonzero structure.
2048: */
2049: PetscErrorCode MatAXPYGetPreallocation_MPIX_private(PetscInt m, const PetscInt *xi, const PetscInt *xj, const PetscInt *xltog, const PetscInt *yi, const PetscInt *yj, const PetscInt *yltog, PetscInt *nnz)
2050: {
2051:   PetscInt i, j, k, nzx, nzy;

2053:   PetscFunctionBegin;
2054:   /* Set the number of nonzeros in the new matrix */
2055:   for (i = 0; i < m; i++) {
2056:     const PetscInt *xjj = PetscSafePointerPlusOffset(xj, xi[i]), *yjj = PetscSafePointerPlusOffset(yj, yi[i]);
2057:     nzx    = xi[i + 1] - xi[i];
2058:     nzy    = yi[i + 1] - yi[i];
2059:     nnz[i] = 0;
2060:     for (j = 0, k = 0; j < nzx; j++) {                                /* Point in X */
2061:       for (; k < nzy && yltog[yjj[k]] < xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2062:       if (k < nzy && yltog[yjj[k]] == xltog[xjj[j]]) k++;             /* Skip duplicate */
2063:       nnz[i]++;
2064:     }
2065:     for (; k < nzy; k++) nnz[i]++;
2066:   }
2067:   PetscFunctionReturn(PETSC_SUCCESS);
2068: }

2070: /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2071: static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y, const PetscInt *yltog, Mat X, const PetscInt *xltog, PetscInt *nnz)
2072: {
2073:   PetscInt    m = Y->rmap->N;
2074:   Mat_SeqAIJ *x = (Mat_SeqAIJ *)X->data;
2075:   Mat_SeqAIJ *y = (Mat_SeqAIJ *)Y->data;

2077:   PetscFunctionBegin;
2078:   PetscCall(MatAXPYGetPreallocation_MPIX_private(m, x->i, x->j, xltog, y->i, y->j, yltog, nnz));
2079:   PetscFunctionReturn(PETSC_SUCCESS);
2080: }

2082: static PetscErrorCode MatAXPY_MPIAIJ(Mat Y, PetscScalar a, Mat X, MatStructure str)
2083: {
2084:   Mat_MPIAIJ *xx = (Mat_MPIAIJ *)X->data, *yy = (Mat_MPIAIJ *)Y->data;

2086:   PetscFunctionBegin;
2087:   if (str == SAME_NONZERO_PATTERN) {
2088:     PetscCall(MatAXPY(yy->A, a, xx->A, str));
2089:     PetscCall(MatAXPY(yy->B, a, xx->B, str));
2090:   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2091:     PetscCall(MatAXPY_Basic(Y, a, X, str));
2092:   } else {
2093:     Mat       B;
2094:     PetscInt *nnz_d, *nnz_o;

2096:     PetscCall(PetscMalloc1(yy->A->rmap->N, &nnz_d));
2097:     PetscCall(PetscMalloc1(yy->B->rmap->N, &nnz_o));
2098:     PetscCall(MatCreate(PetscObjectComm((PetscObject)Y), &B));
2099:     PetscCall(PetscObjectSetName((PetscObject)B, ((PetscObject)Y)->name));
2100:     PetscCall(MatSetLayouts(B, Y->rmap, Y->cmap));
2101:     PetscCall(MatSetType(B, ((PetscObject)Y)->type_name));
2102:     PetscCall(MatAXPYGetPreallocation_SeqAIJ(yy->A, xx->A, nnz_d));
2103:     PetscCall(MatAXPYGetPreallocation_MPIAIJ(yy->B, yy->garray, xx->B, xx->garray, nnz_o));
2104:     PetscCall(MatMPIAIJSetPreallocation(B, 0, nnz_d, 0, nnz_o));
2105:     PetscCall(MatAXPY_BasicWithPreallocation(B, Y, a, X, str));
2106:     PetscCall(MatHeaderMerge(Y, &B));
2107:     PetscCall(PetscFree(nnz_d));
2108:     PetscCall(PetscFree(nnz_o));
2109:   }
2110:   PetscFunctionReturn(PETSC_SUCCESS);
2111: }

2113: PETSC_INTERN PetscErrorCode MatConjugate_SeqAIJ(Mat);

2115: static PetscErrorCode MatConjugate_MPIAIJ(Mat mat)
2116: {
2117:   PetscFunctionBegin;
2118:   if (PetscDefined(USE_COMPLEX)) {
2119:     Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2121:     PetscCall(MatConjugate_SeqAIJ(aij->A));
2122:     PetscCall(MatConjugate_SeqAIJ(aij->B));
2123:   }
2124:   PetscFunctionReturn(PETSC_SUCCESS);
2125: }

2127: static PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2128: {
2129:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2131:   PetscFunctionBegin;
2132:   PetscCall(MatRealPart(a->A));
2133:   PetscCall(MatRealPart(a->B));
2134:   PetscFunctionReturn(PETSC_SUCCESS);
2135: }

2137: static PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2138: {
2139:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2141:   PetscFunctionBegin;
2142:   PetscCall(MatImaginaryPart(a->A));
2143:   PetscCall(MatImaginaryPart(a->B));
2144:   PetscFunctionReturn(PETSC_SUCCESS);
2145: }

2147: static PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2148: {
2149:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
2150:   PetscInt           i, *idxb = NULL, m = A->rmap->n;
2151:   PetscScalar       *va, *vv;
2152:   Vec                vB, vA;
2153:   const PetscScalar *vb;

2155:   PetscFunctionBegin;
2156:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &vA));
2157:   PetscCall(MatGetRowMaxAbs(a->A, vA, idx));

2159:   PetscCall(VecGetArrayWrite(vA, &va));
2160:   if (idx) {
2161:     for (i = 0; i < m; i++) {
2162:       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2163:     }
2164:   }

2166:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &vB));
2167:   PetscCall(PetscMalloc1(m, &idxb));
2168:   PetscCall(MatGetRowMaxAbs(a->B, vB, idxb));

2170:   PetscCall(VecGetArrayWrite(v, &vv));
2171:   PetscCall(VecGetArrayRead(vB, &vb));
2172:   for (i = 0; i < m; i++) {
2173:     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2174:       vv[i] = vb[i];
2175:       if (idx) idx[i] = a->garray[idxb[i]];
2176:     } else {
2177:       vv[i] = va[i];
2178:       if (idx && PetscAbsScalar(va[i]) == PetscAbsScalar(vb[i]) && idxb[i] != -1 && idx[i] > a->garray[idxb[i]]) idx[i] = a->garray[idxb[i]];
2179:     }
2180:   }
2181:   PetscCall(VecRestoreArrayWrite(vA, &vv));
2182:   PetscCall(VecRestoreArrayWrite(vA, &va));
2183:   PetscCall(VecRestoreArrayRead(vB, &vb));
2184:   PetscCall(PetscFree(idxb));
2185:   PetscCall(VecDestroy(&vA));
2186:   PetscCall(VecDestroy(&vB));
2187:   PetscFunctionReturn(PETSC_SUCCESS);
2188: }

2190: static PetscErrorCode MatGetRowSumAbs_MPIAIJ(Mat A, Vec v)
2191: {
2192:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2193:   PetscInt    m = A->rmap->n;
2194:   Vec         vB, vA;

2196:   PetscFunctionBegin;
2197:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &vA));
2198:   PetscCall(MatGetRowSumAbs(a->A, vA));
2199:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &vB));
2200:   PetscCall(MatGetRowSumAbs(a->B, vB));
2201:   PetscCall(VecAXPY(vA, 1.0, vB));
2202:   PetscCall(VecDestroy(&vB));
2203:   PetscCall(VecCopy(vA, v));
2204:   PetscCall(VecDestroy(&vA));
2205:   PetscFunctionReturn(PETSC_SUCCESS);
2206: }

2208: static PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2209: {
2210:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2211:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2212:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2213:   PetscInt          *cmap = mat->garray;
2214:   PetscInt          *diagIdx, *offdiagIdx;
2215:   Vec                diagV, offdiagV;
2216:   PetscScalar       *a, *diagA, *offdiagA;
2217:   const PetscScalar *ba, *bav;
2218:   PetscInt           r, j, col, ncols, *bi, *bj;
2219:   Mat                B = mat->B;
2220:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2222:   PetscFunctionBegin;
2223:   /* When a process holds entire A and other processes have no entry */
2224:   if (A->cmap->N == n) {
2225:     PetscCall(VecGetArrayWrite(v, &diagA));
2226:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2227:     PetscCall(MatGetRowMinAbs(mat->A, diagV, idx));
2228:     PetscCall(VecDestroy(&diagV));
2229:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2230:     PetscFunctionReturn(PETSC_SUCCESS);
2231:   } else if (n == 0) {
2232:     if (m) {
2233:       PetscCall(VecGetArrayWrite(v, &a));
2234:       for (r = 0; r < m; r++) {
2235:         a[r] = 0.0;
2236:         if (idx) idx[r] = -1;
2237:       }
2238:       PetscCall(VecRestoreArrayWrite(v, &a));
2239:     }
2240:     PetscFunctionReturn(PETSC_SUCCESS);
2241:   }

2243:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2244:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2245:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2246:   PetscCall(MatGetRowMinAbs(mat->A, diagV, diagIdx));

2248:   /* Get offdiagIdx[] for implicit 0.0 */
2249:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2250:   ba = bav;
2251:   bi = b->i;
2252:   bj = b->j;
2253:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2254:   for (r = 0; r < m; r++) {
2255:     ncols = bi[r + 1] - bi[r];
2256:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2257:       offdiagA[r]   = *ba;
2258:       offdiagIdx[r] = cmap[0];
2259:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2260:       offdiagA[r] = 0.0;

2262:       /* Find first hole in the cmap */
2263:       for (j = 0; j < ncols; j++) {
2264:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2265:         if (col > j && j < cstart) {
2266:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2267:           break;
2268:         } else if (col > j + n && j >= cstart) {
2269:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2270:           break;
2271:         }
2272:       }
2273:       if (j == ncols && ncols < A->cmap->N - n) {
2274:         /* a hole is outside compressed Bcols */
2275:         if (ncols == 0) {
2276:           if (cstart) {
2277:             offdiagIdx[r] = 0;
2278:           } else offdiagIdx[r] = cend;
2279:         } else { /* ncols > 0 */
2280:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2281:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2282:         }
2283:       }
2284:     }

2286:     for (j = 0; j < ncols; j++) {
2287:       if (PetscAbsScalar(offdiagA[r]) > PetscAbsScalar(*ba)) {
2288:         offdiagA[r]   = *ba;
2289:         offdiagIdx[r] = cmap[*bj];
2290:       }
2291:       ba++;
2292:       bj++;
2293:     }
2294:   }

2296:   PetscCall(VecGetArrayWrite(v, &a));
2297:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2298:   for (r = 0; r < m; ++r) {
2299:     if (PetscAbsScalar(diagA[r]) < PetscAbsScalar(offdiagA[r])) {
2300:       a[r] = diagA[r];
2301:       if (idx) idx[r] = cstart + diagIdx[r];
2302:     } else if (PetscAbsScalar(diagA[r]) == PetscAbsScalar(offdiagA[r])) {
2303:       a[r] = diagA[r];
2304:       if (idx) {
2305:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2306:           idx[r] = cstart + diagIdx[r];
2307:         } else idx[r] = offdiagIdx[r];
2308:       }
2309:     } else {
2310:       a[r] = offdiagA[r];
2311:       if (idx) idx[r] = offdiagIdx[r];
2312:     }
2313:   }
2314:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2315:   PetscCall(VecRestoreArrayWrite(v, &a));
2316:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2317:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2318:   PetscCall(VecDestroy(&diagV));
2319:   PetscCall(VecDestroy(&offdiagV));
2320:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2321:   PetscFunctionReturn(PETSC_SUCCESS);
2322: }

2324: static PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2325: {
2326:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2327:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2328:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2329:   PetscInt          *cmap = mat->garray;
2330:   PetscInt          *diagIdx, *offdiagIdx;
2331:   Vec                diagV, offdiagV;
2332:   PetscScalar       *a, *diagA, *offdiagA;
2333:   const PetscScalar *ba, *bav;
2334:   PetscInt           r, j, col, ncols, *bi, *bj;
2335:   Mat                B = mat->B;
2336:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2338:   PetscFunctionBegin;
2339:   /* When a process holds entire A and other processes have no entry */
2340:   if (A->cmap->N == n) {
2341:     PetscCall(VecGetArrayWrite(v, &diagA));
2342:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2343:     PetscCall(MatGetRowMin(mat->A, diagV, idx));
2344:     PetscCall(VecDestroy(&diagV));
2345:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2346:     PetscFunctionReturn(PETSC_SUCCESS);
2347:   } else if (n == 0) {
2348:     if (m) {
2349:       PetscCall(VecGetArrayWrite(v, &a));
2350:       for (r = 0; r < m; r++) {
2351:         a[r] = PETSC_MAX_REAL;
2352:         if (idx) idx[r] = -1;
2353:       }
2354:       PetscCall(VecRestoreArrayWrite(v, &a));
2355:     }
2356:     PetscFunctionReturn(PETSC_SUCCESS);
2357:   }

2359:   PetscCall(PetscCalloc2(m, &diagIdx, m, &offdiagIdx));
2360:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2361:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2362:   PetscCall(MatGetRowMin(mat->A, diagV, diagIdx));

2364:   /* Get offdiagIdx[] for implicit 0.0 */
2365:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2366:   ba = bav;
2367:   bi = b->i;
2368:   bj = b->j;
2369:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2370:   for (r = 0; r < m; r++) {
2371:     ncols = bi[r + 1] - bi[r];
2372:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2373:       offdiagA[r]   = *ba;
2374:       offdiagIdx[r] = cmap[0];
2375:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2376:       offdiagA[r] = 0.0;

2378:       /* Find first hole in the cmap */
2379:       for (j = 0; j < ncols; j++) {
2380:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2381:         if (col > j && j < cstart) {
2382:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2383:           break;
2384:         } else if (col > j + n && j >= cstart) {
2385:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2386:           break;
2387:         }
2388:       }
2389:       if (j == ncols && ncols < A->cmap->N - n) {
2390:         /* a hole is outside compressed Bcols */
2391:         if (ncols == 0) {
2392:           if (cstart) {
2393:             offdiagIdx[r] = 0;
2394:           } else offdiagIdx[r] = cend;
2395:         } else { /* ncols > 0 */
2396:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2397:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2398:         }
2399:       }
2400:     }

2402:     for (j = 0; j < ncols; j++) {
2403:       if (PetscRealPart(offdiagA[r]) > PetscRealPart(*ba)) {
2404:         offdiagA[r]   = *ba;
2405:         offdiagIdx[r] = cmap[*bj];
2406:       }
2407:       ba++;
2408:       bj++;
2409:     }
2410:   }

2412:   PetscCall(VecGetArrayWrite(v, &a));
2413:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2414:   for (r = 0; r < m; ++r) {
2415:     if (PetscRealPart(diagA[r]) < PetscRealPart(offdiagA[r])) {
2416:       a[r] = diagA[r];
2417:       if (idx) idx[r] = cstart + diagIdx[r];
2418:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2419:       a[r] = diagA[r];
2420:       if (idx) {
2421:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2422:           idx[r] = cstart + diagIdx[r];
2423:         } else idx[r] = offdiagIdx[r];
2424:       }
2425:     } else {
2426:       a[r] = offdiagA[r];
2427:       if (idx) idx[r] = offdiagIdx[r];
2428:     }
2429:   }
2430:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2431:   PetscCall(VecRestoreArrayWrite(v, &a));
2432:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2433:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2434:   PetscCall(VecDestroy(&diagV));
2435:   PetscCall(VecDestroy(&offdiagV));
2436:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2437:   PetscFunctionReturn(PETSC_SUCCESS);
2438: }

2440: static PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2441: {
2442:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2443:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2444:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2445:   PetscInt          *cmap = mat->garray;
2446:   PetscInt          *diagIdx, *offdiagIdx;
2447:   Vec                diagV, offdiagV;
2448:   PetscScalar       *a, *diagA, *offdiagA;
2449:   const PetscScalar *ba, *bav;
2450:   PetscInt           r, j, col, ncols, *bi, *bj;
2451:   Mat                B = mat->B;
2452:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2454:   PetscFunctionBegin;
2455:   /* When a process holds entire A and other processes have no entry */
2456:   if (A->cmap->N == n) {
2457:     PetscCall(VecGetArrayWrite(v, &diagA));
2458:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2459:     PetscCall(MatGetRowMax(mat->A, diagV, idx));
2460:     PetscCall(VecDestroy(&diagV));
2461:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2462:     PetscFunctionReturn(PETSC_SUCCESS);
2463:   } else if (n == 0) {
2464:     if (m) {
2465:       PetscCall(VecGetArrayWrite(v, &a));
2466:       for (r = 0; r < m; r++) {
2467:         a[r] = PETSC_MIN_REAL;
2468:         if (idx) idx[r] = -1;
2469:       }
2470:       PetscCall(VecRestoreArrayWrite(v, &a));
2471:     }
2472:     PetscFunctionReturn(PETSC_SUCCESS);
2473:   }

2475:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2476:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2477:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2478:   PetscCall(MatGetRowMax(mat->A, diagV, diagIdx));

2480:   /* Get offdiagIdx[] for implicit 0.0 */
2481:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2482:   ba = bav;
2483:   bi = b->i;
2484:   bj = b->j;
2485:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2486:   for (r = 0; r < m; r++) {
2487:     ncols = bi[r + 1] - bi[r];
2488:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2489:       offdiagA[r]   = *ba;
2490:       offdiagIdx[r] = cmap[0];
2491:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2492:       offdiagA[r] = 0.0;

2494:       /* Find first hole in the cmap */
2495:       for (j = 0; j < ncols; j++) {
2496:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2497:         if (col > j && j < cstart) {
2498:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2499:           break;
2500:         } else if (col > j + n && j >= cstart) {
2501:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2502:           break;
2503:         }
2504:       }
2505:       if (j == ncols && ncols < A->cmap->N - n) {
2506:         /* a hole is outside compressed Bcols */
2507:         if (ncols == 0) {
2508:           if (cstart) {
2509:             offdiagIdx[r] = 0;
2510:           } else offdiagIdx[r] = cend;
2511:         } else { /* ncols > 0 */
2512:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2513:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2514:         }
2515:       }
2516:     }

2518:     for (j = 0; j < ncols; j++) {
2519:       if (PetscRealPart(offdiagA[r]) < PetscRealPart(*ba)) {
2520:         offdiagA[r]   = *ba;
2521:         offdiagIdx[r] = cmap[*bj];
2522:       }
2523:       ba++;
2524:       bj++;
2525:     }
2526:   }

2528:   PetscCall(VecGetArrayWrite(v, &a));
2529:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2530:   for (r = 0; r < m; ++r) {
2531:     if (PetscRealPart(diagA[r]) > PetscRealPart(offdiagA[r])) {
2532:       a[r] = diagA[r];
2533:       if (idx) idx[r] = cstart + diagIdx[r];
2534:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2535:       a[r] = diagA[r];
2536:       if (idx) {
2537:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2538:           idx[r] = cstart + diagIdx[r];
2539:         } else idx[r] = offdiagIdx[r];
2540:       }
2541:     } else {
2542:       a[r] = offdiagA[r];
2543:       if (idx) idx[r] = offdiagIdx[r];
2544:     }
2545:   }
2546:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2547:   PetscCall(VecRestoreArrayWrite(v, &a));
2548:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2549:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2550:   PetscCall(VecDestroy(&diagV));
2551:   PetscCall(VecDestroy(&offdiagV));
2552:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2553:   PetscFunctionReturn(PETSC_SUCCESS);
2554: }

2556: PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat, Mat *newmat)
2557: {
2558:   Mat *dummy;

2560:   PetscFunctionBegin;
2561:   PetscCall(MatCreateSubMatrix_MPIAIJ_All(mat, MAT_DO_NOT_GET_VALUES, MAT_INITIAL_MATRIX, &dummy));
2562:   *newmat = *dummy;
2563:   PetscCall(PetscFree(dummy));
2564:   PetscFunctionReturn(PETSC_SUCCESS);
2565: }

2567: static PetscErrorCode MatInvertBlockDiagonal_MPIAIJ(Mat A, const PetscScalar **values)
2568: {
2569:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2571:   PetscFunctionBegin;
2572:   PetscCall(MatInvertBlockDiagonal(a->A, values));
2573:   A->factorerrortype = a->A->factorerrortype;
2574:   PetscFunctionReturn(PETSC_SUCCESS);
2575: }

2577: static PetscErrorCode MatSetRandom_MPIAIJ(Mat x, PetscRandom rctx)
2578: {
2579:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)x->data;

2581:   PetscFunctionBegin;
2582:   PetscCheck(x->assembled || x->preallocated, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONGSTATE, "MatSetRandom on an unassembled and unpreallocated MATMPIAIJ is not allowed");
2583:   PetscCall(MatSetRandom(aij->A, rctx));
2584:   if (x->assembled) {
2585:     PetscCall(MatSetRandom(aij->B, rctx));
2586:   } else {
2587:     PetscCall(MatSetRandomSkipColumnRange_SeqAIJ_Private(aij->B, x->cmap->rstart, x->cmap->rend, rctx));
2588:   }
2589:   PetscCall(MatAssemblyBegin(x, MAT_FINAL_ASSEMBLY));
2590:   PetscCall(MatAssemblyEnd(x, MAT_FINAL_ASSEMBLY));
2591:   PetscFunctionReturn(PETSC_SUCCESS);
2592: }

2594: static PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A, PetscBool sc)
2595: {
2596:   PetscFunctionBegin;
2597:   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2598:   else A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ;
2599:   PetscFunctionReturn(PETSC_SUCCESS);
2600: }

2602: /*@
2603:   MatMPIAIJGetNumberNonzeros - gets the number of nonzeros in the matrix on this MPI rank

2605:   Not Collective

2607:   Input Parameter:
2608: . A - the matrix

2610:   Output Parameter:
2611: . nz - the number of nonzeros

2613:   Level: advanced

2615: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2616: @*/
2617: PetscErrorCode MatMPIAIJGetNumberNonzeros(Mat A, PetscCount *nz)
2618: {
2619:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)A->data;
2620:   Mat_SeqAIJ *aaij = (Mat_SeqAIJ *)maij->A->data, *baij = (Mat_SeqAIJ *)maij->B->data;
2621:   PetscBool   isaij;

2623:   PetscFunctionBegin;
2624:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)A, MATMPIAIJ, &isaij));
2625:   PetscCheck(isaij, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Not for type %s", ((PetscObject)A)->type_name);
2626:   *nz = aaij->i[A->rmap->n] + baij->i[A->rmap->n];
2627:   PetscFunctionReturn(PETSC_SUCCESS);
2628: }

2630: /*@
2631:   MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap

2633:   Collective

2635:   Input Parameters:
2636: + A  - the matrix
2637: - sc - `PETSC_TRUE` indicates use the scalable algorithm (default is not to use the scalable algorithm)

2639:   Level: advanced

2641: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2642: @*/
2643: PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A, PetscBool sc)
2644: {
2645:   PetscFunctionBegin;
2646:   PetscTryMethod(A, "MatMPIAIJSetUseScalableIncreaseOverlap_C", (Mat, PetscBool), (A, sc));
2647:   PetscFunctionReturn(PETSC_SUCCESS);
2648: }

2650: PetscErrorCode MatSetFromOptions_MPIAIJ(Mat A, PetscOptionItems *PetscOptionsObject)
2651: {
2652:   PetscBool sc = PETSC_FALSE, flg;

2654:   PetscFunctionBegin;
2655:   PetscOptionsHeadBegin(PetscOptionsObject, "MPIAIJ options");
2656:   if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2657:   PetscCall(PetscOptionsBool("-mat_increase_overlap_scalable", "Use a scalable algorithm to compute the overlap", "MatIncreaseOverlap", sc, &sc, &flg));
2658:   if (flg) PetscCall(MatMPIAIJSetUseScalableIncreaseOverlap(A, sc));
2659:   PetscOptionsHeadEnd();
2660:   PetscFunctionReturn(PETSC_SUCCESS);
2661: }

2663: static PetscErrorCode MatShift_MPIAIJ(Mat Y, PetscScalar a)
2664: {
2665:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)Y->data;
2666:   Mat_SeqAIJ *aij  = (Mat_SeqAIJ *)maij->A->data;

2668:   PetscFunctionBegin;
2669:   if (!Y->preallocated) {
2670:     PetscCall(MatMPIAIJSetPreallocation(Y, 1, NULL, 0, NULL));
2671:   } else if (!aij->nz) { /* It does not matter if diagonals of Y only partially lie in maij->A. We just need an estimated preallocation. */
2672:     PetscInt nonew = aij->nonew;
2673:     PetscCall(MatSeqAIJSetPreallocation(maij->A, 1, NULL));
2674:     aij->nonew = nonew;
2675:   }
2676:   PetscCall(MatShift_Basic(Y, a));
2677:   PetscFunctionReturn(PETSC_SUCCESS);
2678: }

2680: static PetscErrorCode MatMissingDiagonal_MPIAIJ(Mat A, PetscBool *missing, PetscInt *d)
2681: {
2682:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2684:   PetscFunctionBegin;
2685:   PetscCheck(A->rmap->n == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only works for square matrices");
2686:   PetscCall(MatMissingDiagonal(a->A, missing, d));
2687:   if (d) {
2688:     PetscInt rstart;
2689:     PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
2690:     *d += rstart;
2691:   }
2692:   PetscFunctionReturn(PETSC_SUCCESS);
2693: }

2695: static PetscErrorCode MatInvertVariableBlockDiagonal_MPIAIJ(Mat A, PetscInt nblocks, const PetscInt *bsizes, PetscScalar *diag)
2696: {
2697:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2699:   PetscFunctionBegin;
2700:   PetscCall(MatInvertVariableBlockDiagonal(a->A, nblocks, bsizes, diag));
2701:   PetscFunctionReturn(PETSC_SUCCESS);
2702: }

2704: static PetscErrorCode MatEliminateZeros_MPIAIJ(Mat A, PetscBool keep)
2705: {
2706:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2708:   PetscFunctionBegin;
2709:   PetscCall(MatEliminateZeros_SeqAIJ(a->A, keep));        // possibly keep zero diagonal coefficients
2710:   PetscCall(MatEliminateZeros_SeqAIJ(a->B, PETSC_FALSE)); // never keep zero diagonal coefficients
2711:   PetscFunctionReturn(PETSC_SUCCESS);
2712: }

2714: static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2715:                                        MatGetRow_MPIAIJ,
2716:                                        MatRestoreRow_MPIAIJ,
2717:                                        MatMult_MPIAIJ,
2718:                                        /* 4*/ MatMultAdd_MPIAIJ,
2719:                                        MatMultTranspose_MPIAIJ,
2720:                                        MatMultTransposeAdd_MPIAIJ,
2721:                                        NULL,
2722:                                        NULL,
2723:                                        NULL,
2724:                                        /*10*/ NULL,
2725:                                        NULL,
2726:                                        NULL,
2727:                                        MatSOR_MPIAIJ,
2728:                                        MatTranspose_MPIAIJ,
2729:                                        /*15*/ MatGetInfo_MPIAIJ,
2730:                                        MatEqual_MPIAIJ,
2731:                                        MatGetDiagonal_MPIAIJ,
2732:                                        MatDiagonalScale_MPIAIJ,
2733:                                        MatNorm_MPIAIJ,
2734:                                        /*20*/ MatAssemblyBegin_MPIAIJ,
2735:                                        MatAssemblyEnd_MPIAIJ,
2736:                                        MatSetOption_MPIAIJ,
2737:                                        MatZeroEntries_MPIAIJ,
2738:                                        /*24*/ MatZeroRows_MPIAIJ,
2739:                                        NULL,
2740:                                        NULL,
2741:                                        NULL,
2742:                                        NULL,
2743:                                        /*29*/ MatSetUp_MPI_Hash,
2744:                                        NULL,
2745:                                        NULL,
2746:                                        MatGetDiagonalBlock_MPIAIJ,
2747:                                        NULL,
2748:                                        /*34*/ MatDuplicate_MPIAIJ,
2749:                                        NULL,
2750:                                        NULL,
2751:                                        NULL,
2752:                                        NULL,
2753:                                        /*39*/ MatAXPY_MPIAIJ,
2754:                                        MatCreateSubMatrices_MPIAIJ,
2755:                                        MatIncreaseOverlap_MPIAIJ,
2756:                                        MatGetValues_MPIAIJ,
2757:                                        MatCopy_MPIAIJ,
2758:                                        /*44*/ MatGetRowMax_MPIAIJ,
2759:                                        MatScale_MPIAIJ,
2760:                                        MatShift_MPIAIJ,
2761:                                        MatDiagonalSet_MPIAIJ,
2762:                                        MatZeroRowsColumns_MPIAIJ,
2763:                                        /*49*/ MatSetRandom_MPIAIJ,
2764:                                        MatGetRowIJ_MPIAIJ,
2765:                                        MatRestoreRowIJ_MPIAIJ,
2766:                                        NULL,
2767:                                        NULL,
2768:                                        /*54*/ MatFDColoringCreate_MPIXAIJ,
2769:                                        NULL,
2770:                                        MatSetUnfactored_MPIAIJ,
2771:                                        MatPermute_MPIAIJ,
2772:                                        NULL,
2773:                                        /*59*/ MatCreateSubMatrix_MPIAIJ,
2774:                                        MatDestroy_MPIAIJ,
2775:                                        MatView_MPIAIJ,
2776:                                        NULL,
2777:                                        NULL,
2778:                                        /*64*/ NULL,
2779:                                        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2780:                                        NULL,
2781:                                        NULL,
2782:                                        NULL,
2783:                                        /*69*/ MatGetRowMaxAbs_MPIAIJ,
2784:                                        MatGetRowMinAbs_MPIAIJ,
2785:                                        NULL,
2786:                                        NULL,
2787:                                        NULL,
2788:                                        NULL,
2789:                                        /*75*/ MatFDColoringApply_AIJ,
2790:                                        MatSetFromOptions_MPIAIJ,
2791:                                        NULL,
2792:                                        NULL,
2793:                                        MatFindZeroDiagonals_MPIAIJ,
2794:                                        /*80*/ NULL,
2795:                                        NULL,
2796:                                        NULL,
2797:                                        /*83*/ MatLoad_MPIAIJ,
2798:                                        NULL,
2799:                                        NULL,
2800:                                        NULL,
2801:                                        NULL,
2802:                                        NULL,
2803:                                        /*89*/ NULL,
2804:                                        NULL,
2805:                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2806:                                        NULL,
2807:                                        NULL,
2808:                                        /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
2809:                                        NULL,
2810:                                        NULL,
2811:                                        NULL,
2812:                                        MatBindToCPU_MPIAIJ,
2813:                                        /*99*/ MatProductSetFromOptions_MPIAIJ,
2814:                                        NULL,
2815:                                        NULL,
2816:                                        MatConjugate_MPIAIJ,
2817:                                        NULL,
2818:                                        /*104*/ MatSetValuesRow_MPIAIJ,
2819:                                        MatRealPart_MPIAIJ,
2820:                                        MatImaginaryPart_MPIAIJ,
2821:                                        NULL,
2822:                                        NULL,
2823:                                        /*109*/ NULL,
2824:                                        NULL,
2825:                                        MatGetRowMin_MPIAIJ,
2826:                                        NULL,
2827:                                        MatMissingDiagonal_MPIAIJ,
2828:                                        /*114*/ MatGetSeqNonzeroStructure_MPIAIJ,
2829:                                        NULL,
2830:                                        MatGetGhosts_MPIAIJ,
2831:                                        NULL,
2832:                                        NULL,
2833:                                        /*119*/ MatMultDiagonalBlock_MPIAIJ,
2834:                                        NULL,
2835:                                        NULL,
2836:                                        NULL,
2837:                                        MatGetMultiProcBlock_MPIAIJ,
2838:                                        /*124*/ MatFindNonzeroRows_MPIAIJ,
2839:                                        MatGetColumnReductions_MPIAIJ,
2840:                                        MatInvertBlockDiagonal_MPIAIJ,
2841:                                        MatInvertVariableBlockDiagonal_MPIAIJ,
2842:                                        MatCreateSubMatricesMPI_MPIAIJ,
2843:                                        /*129*/ NULL,
2844:                                        NULL,
2845:                                        NULL,
2846:                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2847:                                        NULL,
2848:                                        /*134*/ NULL,
2849:                                        NULL,
2850:                                        NULL,
2851:                                        NULL,
2852:                                        NULL,
2853:                                        /*139*/ MatSetBlockSizes_MPIAIJ,
2854:                                        NULL,
2855:                                        NULL,
2856:                                        MatFDColoringSetUp_MPIXAIJ,
2857:                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2858:                                        MatCreateMPIMatConcatenateSeqMat_MPIAIJ,
2859:                                        /*145*/ NULL,
2860:                                        NULL,
2861:                                        NULL,
2862:                                        MatCreateGraph_Simple_AIJ,
2863:                                        NULL,
2864:                                        /*150*/ NULL,
2865:                                        MatEliminateZeros_MPIAIJ,
2866:                                        MatGetRowSumAbs_MPIAIJ};

2868: static PetscErrorCode MatStoreValues_MPIAIJ(Mat mat)
2869: {
2870:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2872:   PetscFunctionBegin;
2873:   PetscCall(MatStoreValues(aij->A));
2874:   PetscCall(MatStoreValues(aij->B));
2875:   PetscFunctionReturn(PETSC_SUCCESS);
2876: }

2878: static PetscErrorCode MatRetrieveValues_MPIAIJ(Mat mat)
2879: {
2880:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2882:   PetscFunctionBegin;
2883:   PetscCall(MatRetrieveValues(aij->A));
2884:   PetscCall(MatRetrieveValues(aij->B));
2885:   PetscFunctionReturn(PETSC_SUCCESS);
2886: }

2888: PetscErrorCode MatMPIAIJSetPreallocation_MPIAIJ(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
2889: {
2890:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2891:   PetscMPIInt size;

2893:   PetscFunctionBegin;
2894:   if (B->hash_active) {
2895:     B->ops[0]      = b->cops;
2896:     B->hash_active = PETSC_FALSE;
2897:   }
2898:   PetscCall(PetscLayoutSetUp(B->rmap));
2899:   PetscCall(PetscLayoutSetUp(B->cmap));

2901: #if defined(PETSC_USE_CTABLE)
2902:   PetscCall(PetscHMapIDestroy(&b->colmap));
2903: #else
2904:   PetscCall(PetscFree(b->colmap));
2905: #endif
2906:   PetscCall(PetscFree(b->garray));
2907:   PetscCall(VecDestroy(&b->lvec));
2908:   PetscCall(VecScatterDestroy(&b->Mvctx));

2910:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

2912:   MatSeqXAIJGetOptions_Private(b->B);
2913:   PetscCall(MatDestroy(&b->B));
2914:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->B));
2915:   PetscCall(MatSetSizes(b->B, B->rmap->n, size > 1 ? B->cmap->N : 0, B->rmap->n, size > 1 ? B->cmap->N : 0));
2916:   PetscCall(MatSetBlockSizesFromMats(b->B, B, B));
2917:   PetscCall(MatSetType(b->B, MATSEQAIJ));
2918:   MatSeqXAIJRestoreOptions_Private(b->B);

2920:   MatSeqXAIJGetOptions_Private(b->A);
2921:   PetscCall(MatDestroy(&b->A));
2922:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->A));
2923:   PetscCall(MatSetSizes(b->A, B->rmap->n, B->cmap->n, B->rmap->n, B->cmap->n));
2924:   PetscCall(MatSetBlockSizesFromMats(b->A, B, B));
2925:   PetscCall(MatSetType(b->A, MATSEQAIJ));
2926:   MatSeqXAIJRestoreOptions_Private(b->A);

2928:   PetscCall(MatSeqAIJSetPreallocation(b->A, d_nz, d_nnz));
2929:   PetscCall(MatSeqAIJSetPreallocation(b->B, o_nz, o_nnz));
2930:   B->preallocated  = PETSC_TRUE;
2931:   B->was_assembled = PETSC_FALSE;
2932:   B->assembled     = PETSC_FALSE;
2933:   PetscFunctionReturn(PETSC_SUCCESS);
2934: }

2936: static PetscErrorCode MatResetPreallocation_MPIAIJ(Mat B)
2937: {
2938:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2940:   PetscFunctionBegin;
2942:   PetscCall(PetscLayoutSetUp(B->rmap));
2943:   PetscCall(PetscLayoutSetUp(B->cmap));

2945: #if defined(PETSC_USE_CTABLE)
2946:   PetscCall(PetscHMapIDestroy(&b->colmap));
2947: #else
2948:   PetscCall(PetscFree(b->colmap));
2949: #endif
2950:   PetscCall(PetscFree(b->garray));
2951:   PetscCall(VecDestroy(&b->lvec));
2952:   PetscCall(VecScatterDestroy(&b->Mvctx));

2954:   PetscCall(MatResetPreallocation(b->A));
2955:   PetscCall(MatResetPreallocation(b->B));
2956:   B->preallocated  = PETSC_TRUE;
2957:   B->was_assembled = PETSC_FALSE;
2958:   B->assembled     = PETSC_FALSE;
2959:   PetscFunctionReturn(PETSC_SUCCESS);
2960: }

2962: PetscErrorCode MatDuplicate_MPIAIJ(Mat matin, MatDuplicateOption cpvalues, Mat *newmat)
2963: {
2964:   Mat         mat;
2965:   Mat_MPIAIJ *a, *oldmat = (Mat_MPIAIJ *)matin->data;

2967:   PetscFunctionBegin;
2968:   *newmat = NULL;
2969:   PetscCall(MatCreate(PetscObjectComm((PetscObject)matin), &mat));
2970:   PetscCall(MatSetSizes(mat, matin->rmap->n, matin->cmap->n, matin->rmap->N, matin->cmap->N));
2971:   PetscCall(MatSetBlockSizesFromMats(mat, matin, matin));
2972:   PetscCall(MatSetType(mat, ((PetscObject)matin)->type_name));
2973:   a = (Mat_MPIAIJ *)mat->data;

2975:   mat->factortype = matin->factortype;
2976:   mat->assembled  = matin->assembled;
2977:   mat->insertmode = NOT_SET_VALUES;

2979:   a->size         = oldmat->size;
2980:   a->rank         = oldmat->rank;
2981:   a->donotstash   = oldmat->donotstash;
2982:   a->roworiented  = oldmat->roworiented;
2983:   a->rowindices   = NULL;
2984:   a->rowvalues    = NULL;
2985:   a->getrowactive = PETSC_FALSE;

2987:   PetscCall(PetscLayoutReference(matin->rmap, &mat->rmap));
2988:   PetscCall(PetscLayoutReference(matin->cmap, &mat->cmap));
2989:   if (matin->hash_active) {
2990:     PetscCall(MatSetUp(mat));
2991:   } else {
2992:     mat->preallocated = matin->preallocated;
2993:     if (oldmat->colmap) {
2994: #if defined(PETSC_USE_CTABLE)
2995:       PetscCall(PetscHMapIDuplicate(oldmat->colmap, &a->colmap));
2996: #else
2997:       PetscCall(PetscMalloc1(mat->cmap->N, &a->colmap));
2998:       PetscCall(PetscArraycpy(a->colmap, oldmat->colmap, mat->cmap->N));
2999: #endif
3000:     } else a->colmap = NULL;
3001:     if (oldmat->garray) {
3002:       PetscInt len;
3003:       len = oldmat->B->cmap->n;
3004:       PetscCall(PetscMalloc1(len + 1, &a->garray));
3005:       if (len) PetscCall(PetscArraycpy(a->garray, oldmat->garray, len));
3006:     } else a->garray = NULL;

3008:     /* It may happen MatDuplicate is called with a non-assembled matrix
3009:       In fact, MatDuplicate only requires the matrix to be preallocated
3010:       This may happen inside a DMCreateMatrix_Shell */
3011:     if (oldmat->lvec) PetscCall(VecDuplicate(oldmat->lvec, &a->lvec));
3012:     if (oldmat->Mvctx) PetscCall(VecScatterCopy(oldmat->Mvctx, &a->Mvctx));
3013:     PetscCall(MatDuplicate(oldmat->A, cpvalues, &a->A));
3014:     PetscCall(MatDuplicate(oldmat->B, cpvalues, &a->B));
3015:   }
3016:   PetscCall(PetscFunctionListDuplicate(((PetscObject)matin)->qlist, &((PetscObject)mat)->qlist));
3017:   *newmat = mat;
3018:   PetscFunctionReturn(PETSC_SUCCESS);
3019: }

3021: PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3022: {
3023:   PetscBool isbinary, ishdf5;

3025:   PetscFunctionBegin;
3028:   /* force binary viewer to load .info file if it has not yet done so */
3029:   PetscCall(PetscViewerSetUp(viewer));
3030:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
3031:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
3032:   if (isbinary) {
3033:     PetscCall(MatLoad_MPIAIJ_Binary(newMat, viewer));
3034:   } else if (ishdf5) {
3035: #if defined(PETSC_HAVE_HDF5)
3036:     PetscCall(MatLoad_AIJ_HDF5(newMat, viewer));
3037: #else
3038:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
3039: #endif
3040:   } else {
3041:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "Viewer type %s not yet supported for reading %s matrices", ((PetscObject)viewer)->type_name, ((PetscObject)newMat)->type_name);
3042:   }
3043:   PetscFunctionReturn(PETSC_SUCCESS);
3044: }

3046: PetscErrorCode MatLoad_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
3047: {
3048:   PetscInt     header[4], M, N, m, nz, rows, cols, sum, i;
3049:   PetscInt    *rowidxs, *colidxs;
3050:   PetscScalar *matvals;

3052:   PetscFunctionBegin;
3053:   PetscCall(PetscViewerSetUp(viewer));

3055:   /* read in matrix header */
3056:   PetscCall(PetscViewerBinaryRead(viewer, header, 4, NULL, PETSC_INT));
3057:   PetscCheck(header[0] == MAT_FILE_CLASSID, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Not a matrix object in file");
3058:   M  = header[1];
3059:   N  = header[2];
3060:   nz = header[3];
3061:   PetscCheck(M >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix row size (%" PetscInt_FMT ") in file is negative", M);
3062:   PetscCheck(N >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix column size (%" PetscInt_FMT ") in file is negative", N);
3063:   PetscCheck(nz >= 0, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix stored in special format on disk, cannot load as MPIAIJ");

3065:   /* set block sizes from the viewer's .info file */
3066:   PetscCall(MatLoad_Binary_BlockSizes(mat, viewer));
3067:   /* set global sizes if not set already */
3068:   if (mat->rmap->N < 0) mat->rmap->N = M;
3069:   if (mat->cmap->N < 0) mat->cmap->N = N;
3070:   PetscCall(PetscLayoutSetUp(mat->rmap));
3071:   PetscCall(PetscLayoutSetUp(mat->cmap));

3073:   /* check if the matrix sizes are correct */
3074:   PetscCall(MatGetSize(mat, &rows, &cols));
3075:   PetscCheck(M == rows && N == cols, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix in file of different sizes (%" PetscInt_FMT ", %" PetscInt_FMT ") than the input matrix (%" PetscInt_FMT ", %" PetscInt_FMT ")", M, N, rows, cols);

3077:   /* read in row lengths and build row indices */
3078:   PetscCall(MatGetLocalSize(mat, &m, NULL));
3079:   PetscCall(PetscMalloc1(m + 1, &rowidxs));
3080:   PetscCall(PetscViewerBinaryReadAll(viewer, rowidxs + 1, m, PETSC_DECIDE, M, PETSC_INT));
3081:   rowidxs[0] = 0;
3082:   for (i = 0; i < m; i++) rowidxs[i + 1] += rowidxs[i];
3083:   if (nz != PETSC_MAX_INT) {
3084:     PetscCall(MPIU_Allreduce(&rowidxs[m], &sum, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)viewer)));
3085:     PetscCheck(sum == nz, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Inconsistent matrix data in file: nonzeros = %" PetscInt_FMT ", sum-row-lengths = %" PetscInt_FMT, nz, sum);
3086:   }

3088:   /* read in column indices and matrix values */
3089:   PetscCall(PetscMalloc2(rowidxs[m], &colidxs, rowidxs[m], &matvals));
3090:   PetscCall(PetscViewerBinaryReadAll(viewer, colidxs, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
3091:   PetscCall(PetscViewerBinaryReadAll(viewer, matvals, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
3092:   /* store matrix indices and values */
3093:   PetscCall(MatMPIAIJSetPreallocationCSR(mat, rowidxs, colidxs, matvals));
3094:   PetscCall(PetscFree(rowidxs));
3095:   PetscCall(PetscFree2(colidxs, matvals));
3096:   PetscFunctionReturn(PETSC_SUCCESS);
3097: }

3099: /* Not scalable because of ISAllGather() unless getting all columns. */
3100: static PetscErrorCode ISGetSeqIS_Private(Mat mat, IS iscol, IS *isseq)
3101: {
3102:   IS          iscol_local;
3103:   PetscBool   isstride;
3104:   PetscMPIInt lisstride = 0, gisstride;

3106:   PetscFunctionBegin;
3107:   /* check if we are grabbing all columns*/
3108:   PetscCall(PetscObjectTypeCompare((PetscObject)iscol, ISSTRIDE, &isstride));

3110:   if (isstride) {
3111:     PetscInt start, len, mstart, mlen;
3112:     PetscCall(ISStrideGetInfo(iscol, &start, NULL));
3113:     PetscCall(ISGetLocalSize(iscol, &len));
3114:     PetscCall(MatGetOwnershipRangeColumn(mat, &mstart, &mlen));
3115:     if (mstart == start && mlen - mstart == len) lisstride = 1;
3116:   }

3118:   PetscCall(MPIU_Allreduce(&lisstride, &gisstride, 1, MPI_INT, MPI_MIN, PetscObjectComm((PetscObject)mat)));
3119:   if (gisstride) {
3120:     PetscInt N;
3121:     PetscCall(MatGetSize(mat, NULL, &N));
3122:     PetscCall(ISCreateStride(PETSC_COMM_SELF, N, 0, 1, &iscol_local));
3123:     PetscCall(ISSetIdentity(iscol_local));
3124:     PetscCall(PetscInfo(mat, "Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n"));
3125:   } else {
3126:     PetscInt cbs;
3127:     PetscCall(ISGetBlockSize(iscol, &cbs));
3128:     PetscCall(ISAllGather(iscol, &iscol_local));
3129:     PetscCall(ISSetBlockSize(iscol_local, cbs));
3130:   }

3132:   *isseq = iscol_local;
3133:   PetscFunctionReturn(PETSC_SUCCESS);
3134: }

3136: /*
3137:  Used by MatCreateSubMatrix_MPIAIJ_SameRowColDist() to avoid ISAllGather() and global size of iscol_local
3138:  (see MatCreateSubMatrix_MPIAIJ_nonscalable)

3140:  Input Parameters:
3141: +   mat - matrix
3142: .   isrow - parallel row index set; its local indices are a subset of local columns of `mat`,
3143:            i.e., mat->rstart <= isrow[i] < mat->rend
3144: -   iscol - parallel column index set; its local indices are a subset of local columns of `mat`,
3145:            i.e., mat->cstart <= iscol[i] < mat->cend

3147:  Output Parameters:
3148: +   isrow_d - sequential row index set for retrieving mat->A
3149: .   iscol_d - sequential  column index set for retrieving mat->A
3150: .   iscol_o - sequential column index set for retrieving mat->B
3151: -   garray - column map; garray[i] indicates global location of iscol_o[i] in `iscol`
3152:  */
3153: static PetscErrorCode ISGetSeqIS_SameColDist_Private(Mat mat, IS isrow, IS iscol, IS *isrow_d, IS *iscol_d, IS *iscol_o, const PetscInt *garray[])
3154: {
3155:   Vec             x, cmap;
3156:   const PetscInt *is_idx;
3157:   PetscScalar    *xarray, *cmaparray;
3158:   PetscInt        ncols, isstart, *idx, m, rstart, *cmap1, count;
3159:   Mat_MPIAIJ     *a    = (Mat_MPIAIJ *)mat->data;
3160:   Mat             B    = a->B;
3161:   Vec             lvec = a->lvec, lcmap;
3162:   PetscInt        i, cstart, cend, Bn = B->cmap->N;
3163:   MPI_Comm        comm;
3164:   VecScatter      Mvctx = a->Mvctx;

3166:   PetscFunctionBegin;
3167:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3168:   PetscCall(ISGetLocalSize(iscol, &ncols));

3170:   /* (1) iscol is a sub-column vector of mat, pad it with '-1.' to form a full vector x */
3171:   PetscCall(MatCreateVecs(mat, &x, NULL));
3172:   PetscCall(VecSet(x, -1.0));
3173:   PetscCall(VecDuplicate(x, &cmap));
3174:   PetscCall(VecSet(cmap, -1.0));

3176:   /* Get start indices */
3177:   PetscCallMPI(MPI_Scan(&ncols, &isstart, 1, MPIU_INT, MPI_SUM, comm));
3178:   isstart -= ncols;
3179:   PetscCall(MatGetOwnershipRangeColumn(mat, &cstart, &cend));

3181:   PetscCall(ISGetIndices(iscol, &is_idx));
3182:   PetscCall(VecGetArray(x, &xarray));
3183:   PetscCall(VecGetArray(cmap, &cmaparray));
3184:   PetscCall(PetscMalloc1(ncols, &idx));
3185:   for (i = 0; i < ncols; i++) {
3186:     xarray[is_idx[i] - cstart]    = (PetscScalar)is_idx[i];
3187:     cmaparray[is_idx[i] - cstart] = i + isstart;        /* global index of iscol[i] */
3188:     idx[i]                        = is_idx[i] - cstart; /* local index of iscol[i]  */
3189:   }
3190:   PetscCall(VecRestoreArray(x, &xarray));
3191:   PetscCall(VecRestoreArray(cmap, &cmaparray));
3192:   PetscCall(ISRestoreIndices(iscol, &is_idx));

3194:   /* Get iscol_d */
3195:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, iscol_d));
3196:   PetscCall(ISGetBlockSize(iscol, &i));
3197:   PetscCall(ISSetBlockSize(*iscol_d, i));

3199:   /* Get isrow_d */
3200:   PetscCall(ISGetLocalSize(isrow, &m));
3201:   rstart = mat->rmap->rstart;
3202:   PetscCall(PetscMalloc1(m, &idx));
3203:   PetscCall(ISGetIndices(isrow, &is_idx));
3204:   for (i = 0; i < m; i++) idx[i] = is_idx[i] - rstart;
3205:   PetscCall(ISRestoreIndices(isrow, &is_idx));

3207:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx, PETSC_OWN_POINTER, isrow_d));
3208:   PetscCall(ISGetBlockSize(isrow, &i));
3209:   PetscCall(ISSetBlockSize(*isrow_d, i));

3211:   /* (2) Scatter x and cmap using aij->Mvctx to get their off-process portions (see MatMult_MPIAIJ) */
3212:   PetscCall(VecScatterBegin(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));
3213:   PetscCall(VecScatterEnd(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));

3215:   PetscCall(VecDuplicate(lvec, &lcmap));

3217:   PetscCall(VecScatterBegin(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));
3218:   PetscCall(VecScatterEnd(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));

3220:   /* (3) create sequential iscol_o (a subset of iscol) and isgarray */
3221:   /* off-process column indices */
3222:   count = 0;
3223:   PetscCall(PetscMalloc1(Bn, &idx));
3224:   PetscCall(PetscMalloc1(Bn, &cmap1));

3226:   PetscCall(VecGetArray(lvec, &xarray));
3227:   PetscCall(VecGetArray(lcmap, &cmaparray));
3228:   for (i = 0; i < Bn; i++) {
3229:     if (PetscRealPart(xarray[i]) > -1.0) {
3230:       idx[count]   = i;                                     /* local column index in off-diagonal part B */
3231:       cmap1[count] = (PetscInt)PetscRealPart(cmaparray[i]); /* column index in submat */
3232:       count++;
3233:     }
3234:   }
3235:   PetscCall(VecRestoreArray(lvec, &xarray));
3236:   PetscCall(VecRestoreArray(lcmap, &cmaparray));

3238:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_COPY_VALUES, iscol_o));
3239:   /* cannot ensure iscol_o has same blocksize as iscol! */

3241:   PetscCall(PetscFree(idx));
3242:   *garray = cmap1;

3244:   PetscCall(VecDestroy(&x));
3245:   PetscCall(VecDestroy(&cmap));
3246:   PetscCall(VecDestroy(&lcmap));
3247:   PetscFunctionReturn(PETSC_SUCCESS);
3248: }

3250: /* isrow and iscol have same processor distribution as mat, output *submat is a submatrix of local mat */
3251: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowColDist(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *submat)
3252: {
3253:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)mat->data, *asub;
3254:   Mat         M = NULL;
3255:   MPI_Comm    comm;
3256:   IS          iscol_d, isrow_d, iscol_o;
3257:   Mat         Asub = NULL, Bsub = NULL;
3258:   PetscInt    n;

3260:   PetscFunctionBegin;
3261:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));

3263:   if (call == MAT_REUSE_MATRIX) {
3264:     /* Retrieve isrow_d, iscol_d and iscol_o from submat */
3265:     PetscCall(PetscObjectQuery((PetscObject)*submat, "isrow_d", (PetscObject *)&isrow_d));
3266:     PetscCheck(isrow_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "isrow_d passed in was not used before, cannot reuse");

3268:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_d", (PetscObject *)&iscol_d));
3269:     PetscCheck(iscol_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_d passed in was not used before, cannot reuse");

3271:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_o", (PetscObject *)&iscol_o));
3272:     PetscCheck(iscol_o, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_o passed in was not used before, cannot reuse");

3274:     /* Update diagonal and off-diagonal portions of submat */
3275:     asub = (Mat_MPIAIJ *)(*submat)->data;
3276:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->A));
3277:     PetscCall(ISGetLocalSize(iscol_o, &n));
3278:     if (n) PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->B));
3279:     PetscCall(MatAssemblyBegin(*submat, MAT_FINAL_ASSEMBLY));
3280:     PetscCall(MatAssemblyEnd(*submat, MAT_FINAL_ASSEMBLY));

3282:   } else { /* call == MAT_INITIAL_MATRIX) */
3283:     const PetscInt *garray;
3284:     PetscInt        BsubN;

3286:     /* Create isrow_d, iscol_d, iscol_o and isgarray (replace isgarray with array?) */
3287:     PetscCall(ISGetSeqIS_SameColDist_Private(mat, isrow, iscol, &isrow_d, &iscol_d, &iscol_o, &garray));

3289:     /* Create local submatrices Asub and Bsub */
3290:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Asub));
3291:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Bsub));

3293:     /* Create submatrix M */
3294:     PetscCall(MatCreateMPIAIJWithSeqAIJ(comm, Asub, Bsub, garray, &M));

3296:     /* If Bsub has empty columns, compress iscol_o such that it will retrieve condensed Bsub from a->B during reuse */
3297:     asub = (Mat_MPIAIJ *)M->data;

3299:     PetscCall(ISGetLocalSize(iscol_o, &BsubN));
3300:     n = asub->B->cmap->N;
3301:     if (BsubN > n) {
3302:       /* This case can be tested using ~petsc/src/tao/bound/tutorials/runplate2_3 */
3303:       const PetscInt *idx;
3304:       PetscInt        i, j, *idx_new, *subgarray = asub->garray;
3305:       PetscCall(PetscInfo(M, "submatrix Bn %" PetscInt_FMT " != BsubN %" PetscInt_FMT ", update iscol_o\n", n, BsubN));

3307:       PetscCall(PetscMalloc1(n, &idx_new));
3308:       j = 0;
3309:       PetscCall(ISGetIndices(iscol_o, &idx));
3310:       for (i = 0; i < n; i++) {
3311:         if (j >= BsubN) break;
3312:         while (subgarray[i] > garray[j]) j++;

3314:         if (subgarray[i] == garray[j]) {
3315:           idx_new[i] = idx[j++];
3316:         } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "subgarray[%" PetscInt_FMT "]=%" PetscInt_FMT " cannot < garray[%" PetscInt_FMT "]=%" PetscInt_FMT, i, subgarray[i], j, garray[j]);
3317:       }
3318:       PetscCall(ISRestoreIndices(iscol_o, &idx));

3320:       PetscCall(ISDestroy(&iscol_o));
3321:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, idx_new, PETSC_OWN_POINTER, &iscol_o));

3323:     } else if (BsubN < n) {
3324:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Columns of Bsub (%" PetscInt_FMT ") cannot be smaller than B's (%" PetscInt_FMT ")", BsubN, asub->B->cmap->N);
3325:     }

3327:     PetscCall(PetscFree(garray));
3328:     *submat = M;

3330:     /* Save isrow_d, iscol_d and iscol_o used in processor for next request */
3331:     PetscCall(PetscObjectCompose((PetscObject)M, "isrow_d", (PetscObject)isrow_d));
3332:     PetscCall(ISDestroy(&isrow_d));

3334:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_d", (PetscObject)iscol_d));
3335:     PetscCall(ISDestroy(&iscol_d));

3337:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_o", (PetscObject)iscol_o));
3338:     PetscCall(ISDestroy(&iscol_o));
3339:   }
3340:   PetscFunctionReturn(PETSC_SUCCESS);
3341: }

3343: PetscErrorCode MatCreateSubMatrix_MPIAIJ(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *newmat)
3344: {
3345:   IS        iscol_local = NULL, isrow_d;
3346:   PetscInt  csize;
3347:   PetscInt  n, i, j, start, end;
3348:   PetscBool sameRowDist = PETSC_FALSE, sameDist[2], tsameDist[2];
3349:   MPI_Comm  comm;

3351:   PetscFunctionBegin;
3352:   /* If isrow has same processor distribution as mat,
3353:      call MatCreateSubMatrix_MPIAIJ_SameRowDist() to avoid using a hash table with global size of iscol */
3354:   if (call == MAT_REUSE_MATRIX) {
3355:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "isrow_d", (PetscObject *)&isrow_d));
3356:     if (isrow_d) {
3357:       sameRowDist  = PETSC_TRUE;
3358:       tsameDist[1] = PETSC_TRUE; /* sameColDist */
3359:     } else {
3360:       PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_local));
3361:       if (iscol_local) {
3362:         sameRowDist  = PETSC_TRUE;
3363:         tsameDist[1] = PETSC_FALSE; /* !sameColDist */
3364:       }
3365:     }
3366:   } else {
3367:     /* Check if isrow has same processor distribution as mat */
3368:     sameDist[0] = PETSC_FALSE;
3369:     PetscCall(ISGetLocalSize(isrow, &n));
3370:     if (!n) {
3371:       sameDist[0] = PETSC_TRUE;
3372:     } else {
3373:       PetscCall(ISGetMinMax(isrow, &i, &j));
3374:       PetscCall(MatGetOwnershipRange(mat, &start, &end));
3375:       if (i >= start && j < end) sameDist[0] = PETSC_TRUE;
3376:     }

3378:     /* Check if iscol has same processor distribution as mat */
3379:     sameDist[1] = PETSC_FALSE;
3380:     PetscCall(ISGetLocalSize(iscol, &n));
3381:     if (!n) {
3382:       sameDist[1] = PETSC_TRUE;
3383:     } else {
3384:       PetscCall(ISGetMinMax(iscol, &i, &j));
3385:       PetscCall(MatGetOwnershipRangeColumn(mat, &start, &end));
3386:       if (i >= start && j < end) sameDist[1] = PETSC_TRUE;
3387:     }

3389:     PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3390:     PetscCall(MPIU_Allreduce(&sameDist, &tsameDist, 2, MPIU_BOOL, MPI_LAND, comm));
3391:     sameRowDist = tsameDist[0];
3392:   }

3394:   if (sameRowDist) {
3395:     if (tsameDist[1]) { /* sameRowDist & sameColDist */
3396:       /* isrow and iscol have same processor distribution as mat */
3397:       PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowColDist(mat, isrow, iscol, call, newmat));
3398:       PetscFunctionReturn(PETSC_SUCCESS);
3399:     } else { /* sameRowDist */
3400:       /* isrow has same processor distribution as mat */
3401:       if (call == MAT_INITIAL_MATRIX) {
3402:         PetscBool sorted;
3403:         PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3404:         PetscCall(ISGetLocalSize(iscol_local, &n)); /* local size of iscol_local = global columns of newmat */
3405:         PetscCall(ISGetSize(iscol, &i));
3406:         PetscCheck(n == i, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "n %" PetscInt_FMT " != size of iscol %" PetscInt_FMT, n, i);

3408:         PetscCall(ISSorted(iscol_local, &sorted));
3409:         if (sorted) {
3410:           /* MatCreateSubMatrix_MPIAIJ_SameRowDist() requires iscol_local be sorted; it can have duplicate indices */
3411:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, iscol_local, MAT_INITIAL_MATRIX, newmat));
3412:           PetscFunctionReturn(PETSC_SUCCESS);
3413:         }
3414:       } else { /* call == MAT_REUSE_MATRIX */
3415:         IS iscol_sub;
3416:         PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3417:         if (iscol_sub) {
3418:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, NULL, call, newmat));
3419:           PetscFunctionReturn(PETSC_SUCCESS);
3420:         }
3421:       }
3422:     }
3423:   }

3425:   /* General case: iscol -> iscol_local which has global size of iscol */
3426:   if (call == MAT_REUSE_MATRIX) {
3427:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "ISAllGather", (PetscObject *)&iscol_local));
3428:     PetscCheck(iscol_local, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3429:   } else {
3430:     if (!iscol_local) PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3431:   }

3433:   PetscCall(ISGetLocalSize(iscol, &csize));
3434:   PetscCall(MatCreateSubMatrix_MPIAIJ_nonscalable(mat, isrow, iscol_local, csize, call, newmat));

3436:   if (call == MAT_INITIAL_MATRIX) {
3437:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3438:     PetscCall(ISDestroy(&iscol_local));
3439:   }
3440:   PetscFunctionReturn(PETSC_SUCCESS);
3441: }

3443: /*@C
3444:   MatCreateMPIAIJWithSeqAIJ - creates a `MATMPIAIJ` matrix using `MATSEQAIJ` matrices that contain the "diagonal"
3445:   and "off-diagonal" part of the matrix in CSR format.

3447:   Collective

3449:   Input Parameters:
3450: + comm   - MPI communicator
3451: . A      - "diagonal" portion of matrix
3452: . B      - "off-diagonal" portion of matrix, may have empty columns, will be destroyed by this routine
3453: - garray - global index of `B` columns

3455:   Output Parameter:
3456: . mat - the matrix, with input `A` as its local diagonal matrix

3458:   Level: advanced

3460:   Notes:
3461:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix.

3463:   `A` becomes part of output mat, `B` is destroyed by this routine. The user cannot use `A` and `B` anymore.

3465: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJWithSplitArrays()`
3466: @*/
3467: PetscErrorCode MatCreateMPIAIJWithSeqAIJ(MPI_Comm comm, Mat A, Mat B, const PetscInt garray[], Mat *mat)
3468: {
3469:   Mat_MPIAIJ        *maij;
3470:   Mat_SeqAIJ        *b  = (Mat_SeqAIJ *)B->data, *bnew;
3471:   PetscInt          *oi = b->i, *oj = b->j, i, nz, col;
3472:   const PetscScalar *oa;
3473:   Mat                Bnew;
3474:   PetscInt           m, n, N;
3475:   MatType            mpi_mat_type;

3477:   PetscFunctionBegin;
3478:   PetscCall(MatCreate(comm, mat));
3479:   PetscCall(MatGetSize(A, &m, &n));
3480:   PetscCheck(m == B->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Am %" PetscInt_FMT " != Bm %" PetscInt_FMT, m, B->rmap->N);
3481:   PetscCheck(PetscAbs(A->rmap->bs) == PetscAbs(B->rmap->bs), PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "A row bs %" PetscInt_FMT " != B row bs %" PetscInt_FMT, A->rmap->bs, B->rmap->bs);
3482:   /* remove check below; When B is created using iscol_o from ISGetSeqIS_SameColDist_Private(), its bs may not be same as A */
3483:   /* PetscCheck(A->cmap->bs == B->cmap->bs,PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"A column bs %" PetscInt_FMT " != B column bs %" PetscInt_FMT,A->cmap->bs,B->cmap->bs); */

3485:   /* Get global columns of mat */
3486:   PetscCall(MPIU_Allreduce(&n, &N, 1, MPIU_INT, MPI_SUM, comm));

3488:   PetscCall(MatSetSizes(*mat, m, n, PETSC_DECIDE, N));
3489:   /* Determine the type of MPI matrix that should be created from the type of matrix A, which holds the "diagonal" portion. */
3490:   PetscCall(MatGetMPIMatType_Private(A, &mpi_mat_type));
3491:   PetscCall(MatSetType(*mat, mpi_mat_type));

3493:   if (A->rmap->bs > 1 || A->cmap->bs > 1) PetscCall(MatSetBlockSizes(*mat, A->rmap->bs, A->cmap->bs));
3494:   maij = (Mat_MPIAIJ *)(*mat)->data;

3496:   (*mat)->preallocated = PETSC_TRUE;

3498:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
3499:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

3501:   /* Set A as diagonal portion of *mat */
3502:   maij->A = A;

3504:   nz = oi[m];
3505:   for (i = 0; i < nz; i++) {
3506:     col   = oj[i];
3507:     oj[i] = garray[col];
3508:   }

3510:   /* Set Bnew as off-diagonal portion of *mat */
3511:   PetscCall(MatSeqAIJGetArrayRead(B, &oa));
3512:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, N, oi, oj, (PetscScalar *)oa, &Bnew));
3513:   PetscCall(MatSeqAIJRestoreArrayRead(B, &oa));
3514:   bnew        = (Mat_SeqAIJ *)Bnew->data;
3515:   bnew->maxnz = b->maxnz; /* allocated nonzeros of B */
3516:   maij->B     = Bnew;

3518:   PetscCheck(B->rmap->N == Bnew->rmap->N, PETSC_COMM_SELF, PETSC_ERR_PLIB, "BN %" PetscInt_FMT " != BnewN %" PetscInt_FMT, B->rmap->N, Bnew->rmap->N);

3520:   b->singlemalloc = PETSC_FALSE; /* B arrays are shared by Bnew */
3521:   b->free_a       = PETSC_FALSE;
3522:   b->free_ij      = PETSC_FALSE;
3523:   PetscCall(MatDestroy(&B));

3525:   bnew->singlemalloc = PETSC_TRUE; /* arrays will be freed by MatDestroy(&Bnew) */
3526:   bnew->free_a       = PETSC_TRUE;
3527:   bnew->free_ij      = PETSC_TRUE;

3529:   /* condense columns of maij->B */
3530:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
3531:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
3532:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
3533:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
3534:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3535:   PetscFunctionReturn(PETSC_SUCCESS);
3536: }

3538: extern PetscErrorCode MatCreateSubMatrices_MPIAIJ_SingleIS_Local(Mat, PetscInt, const IS[], const IS[], MatReuse, PetscBool, Mat *);

3540: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowDist(Mat mat, IS isrow, IS iscol, IS iscol_local, MatReuse call, Mat *newmat)
3541: {
3542:   PetscInt        i, m, n, rstart, row, rend, nz, j, bs, cbs;
3543:   PetscInt       *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3544:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)mat->data;
3545:   Mat             M, Msub, B = a->B;
3546:   MatScalar      *aa;
3547:   Mat_SeqAIJ     *aij;
3548:   PetscInt       *garray = a->garray, *colsub, Ncols;
3549:   PetscInt        count, Bn = B->cmap->N, cstart = mat->cmap->rstart, cend = mat->cmap->rend;
3550:   IS              iscol_sub, iscmap;
3551:   const PetscInt *is_idx, *cmap;
3552:   PetscBool       allcolumns = PETSC_FALSE;
3553:   MPI_Comm        comm;

3555:   PetscFunctionBegin;
3556:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3557:   if (call == MAT_REUSE_MATRIX) {
3558:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3559:     PetscCheck(iscol_sub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "SubIScol passed in was not used before, cannot reuse");
3560:     PetscCall(ISGetLocalSize(iscol_sub, &count));

3562:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "Subcmap", (PetscObject *)&iscmap));
3563:     PetscCheck(iscmap, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Subcmap passed in was not used before, cannot reuse");

3565:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Msub));
3566:     PetscCheck(Msub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");

3568:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_REUSE_MATRIX, PETSC_FALSE, &Msub));

3570:   } else { /* call == MAT_INITIAL_MATRIX) */
3571:     PetscBool flg;

3573:     PetscCall(ISGetLocalSize(iscol, &n));
3574:     PetscCall(ISGetSize(iscol, &Ncols));

3576:     /* (1) iscol -> nonscalable iscol_local */
3577:     /* Check for special case: each processor gets entire matrix columns */
3578:     PetscCall(ISIdentity(iscol_local, &flg));
3579:     if (flg && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3580:     PetscCall(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
3581:     if (allcolumns) {
3582:       iscol_sub = iscol_local;
3583:       PetscCall(PetscObjectReference((PetscObject)iscol_local));
3584:       PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &iscmap));

3586:     } else {
3587:       /* (2) iscol_local -> iscol_sub and iscmap. Implementation below requires iscol_local be sorted, it can have duplicate indices */
3588:       PetscInt *idx, *cmap1, k;
3589:       PetscCall(PetscMalloc1(Ncols, &idx));
3590:       PetscCall(PetscMalloc1(Ncols, &cmap1));
3591:       PetscCall(ISGetIndices(iscol_local, &is_idx));
3592:       count = 0;
3593:       k     = 0;
3594:       for (i = 0; i < Ncols; i++) {
3595:         j = is_idx[i];
3596:         if (j >= cstart && j < cend) {
3597:           /* diagonal part of mat */
3598:           idx[count]     = j;
3599:           cmap1[count++] = i; /* column index in submat */
3600:         } else if (Bn) {
3601:           /* off-diagonal part of mat */
3602:           if (j == garray[k]) {
3603:             idx[count]     = j;
3604:             cmap1[count++] = i; /* column index in submat */
3605:           } else if (j > garray[k]) {
3606:             while (j > garray[k] && k < Bn - 1) k++;
3607:             if (j == garray[k]) {
3608:               idx[count]     = j;
3609:               cmap1[count++] = i; /* column index in submat */
3610:             }
3611:           }
3612:         }
3613:       }
3614:       PetscCall(ISRestoreIndices(iscol_local, &is_idx));

3616:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_OWN_POINTER, &iscol_sub));
3617:       PetscCall(ISGetBlockSize(iscol, &cbs));
3618:       PetscCall(ISSetBlockSize(iscol_sub, cbs));

3620:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)iscol_local), count, cmap1, PETSC_OWN_POINTER, &iscmap));
3621:     }

3623:     /* (3) Create sequential Msub */
3624:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_INITIAL_MATRIX, allcolumns, &Msub));
3625:   }

3627:   PetscCall(ISGetLocalSize(iscol_sub, &count));
3628:   aij = (Mat_SeqAIJ *)(Msub)->data;
3629:   ii  = aij->i;
3630:   PetscCall(ISGetIndices(iscmap, &cmap));

3632:   /*
3633:       m - number of local rows
3634:       Ncols - number of columns (same on all processors)
3635:       rstart - first row in new global matrix generated
3636:   */
3637:   PetscCall(MatGetSize(Msub, &m, NULL));

3639:   if (call == MAT_INITIAL_MATRIX) {
3640:     /* (4) Create parallel newmat */
3641:     PetscMPIInt rank, size;
3642:     PetscInt    csize;

3644:     PetscCallMPI(MPI_Comm_size(comm, &size));
3645:     PetscCallMPI(MPI_Comm_rank(comm, &rank));

3647:     /*
3648:         Determine the number of non-zeros in the diagonal and off-diagonal
3649:         portions of the matrix in order to do correct preallocation
3650:     */

3652:     /* first get start and end of "diagonal" columns */
3653:     PetscCall(ISGetLocalSize(iscol, &csize));
3654:     if (csize == PETSC_DECIDE) {
3655:       PetscCall(ISGetSize(isrow, &mglobal));
3656:       if (mglobal == Ncols) { /* square matrix */
3657:         nlocal = m;
3658:       } else {
3659:         nlocal = Ncols / size + ((Ncols % size) > rank);
3660:       }
3661:     } else {
3662:       nlocal = csize;
3663:     }
3664:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3665:     rstart = rend - nlocal;
3666:     PetscCheck(rank != size - 1 || rend == Ncols, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Local column sizes %" PetscInt_FMT " do not add up to total number of columns %" PetscInt_FMT, rend, Ncols);

3668:     /* next, compute all the lengths */
3669:     jj = aij->j;
3670:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3671:     olens = dlens + m;
3672:     for (i = 0; i < m; i++) {
3673:       jend = ii[i + 1] - ii[i];
3674:       olen = 0;
3675:       dlen = 0;
3676:       for (j = 0; j < jend; j++) {
3677:         if (cmap[*jj] < rstart || cmap[*jj] >= rend) olen++;
3678:         else dlen++;
3679:         jj++;
3680:       }
3681:       olens[i] = olen;
3682:       dlens[i] = dlen;
3683:     }

3685:     PetscCall(ISGetBlockSize(isrow, &bs));
3686:     PetscCall(ISGetBlockSize(iscol, &cbs));

3688:     PetscCall(MatCreate(comm, &M));
3689:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, Ncols));
3690:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3691:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3692:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3693:     PetscCall(PetscFree(dlens));

3695:   } else { /* call == MAT_REUSE_MATRIX */
3696:     M = *newmat;
3697:     PetscCall(MatGetLocalSize(M, &i, NULL));
3698:     PetscCheck(i == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3699:     PetscCall(MatZeroEntries(M));
3700:     /*
3701:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3702:        rather than the slower MatSetValues().
3703:     */
3704:     M->was_assembled = PETSC_TRUE;
3705:     M->assembled     = PETSC_FALSE;
3706:   }

3708:   /* (5) Set values of Msub to *newmat */
3709:   PetscCall(PetscMalloc1(count, &colsub));
3710:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));

3712:   jj = aij->j;
3713:   PetscCall(MatSeqAIJGetArrayRead(Msub, (const PetscScalar **)&aa));
3714:   for (i = 0; i < m; i++) {
3715:     row = rstart + i;
3716:     nz  = ii[i + 1] - ii[i];
3717:     for (j = 0; j < nz; j++) colsub[j] = cmap[jj[j]];
3718:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, colsub, aa, INSERT_VALUES));
3719:     jj += nz;
3720:     aa += nz;
3721:   }
3722:   PetscCall(MatSeqAIJRestoreArrayRead(Msub, (const PetscScalar **)&aa));
3723:   PetscCall(ISRestoreIndices(iscmap, &cmap));

3725:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3726:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));

3728:   PetscCall(PetscFree(colsub));

3730:   /* save Msub, iscol_sub and iscmap used in processor for next request */
3731:   if (call == MAT_INITIAL_MATRIX) {
3732:     *newmat = M;
3733:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubMatrix", (PetscObject)Msub));
3734:     PetscCall(MatDestroy(&Msub));

3736:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubIScol", (PetscObject)iscol_sub));
3737:     PetscCall(ISDestroy(&iscol_sub));

3739:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "Subcmap", (PetscObject)iscmap));
3740:     PetscCall(ISDestroy(&iscmap));

3742:     if (iscol_local) {
3743:       PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3744:       PetscCall(ISDestroy(&iscol_local));
3745:     }
3746:   }
3747:   PetscFunctionReturn(PETSC_SUCCESS);
3748: }

3750: /*
3751:     Not great since it makes two copies of the submatrix, first an SeqAIJ
3752:   in local and then by concatenating the local matrices the end result.
3753:   Writing it directly would be much like MatCreateSubMatrices_MPIAIJ()

3755:   This requires a sequential iscol with all indices.
3756: */
3757: PetscErrorCode MatCreateSubMatrix_MPIAIJ_nonscalable(Mat mat, IS isrow, IS iscol, PetscInt csize, MatReuse call, Mat *newmat)
3758: {
3759:   PetscMPIInt rank, size;
3760:   PetscInt    i, m, n, rstart, row, rend, nz, *cwork, j, bs, cbs;
3761:   PetscInt   *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3762:   Mat         M, Mreuse;
3763:   MatScalar  *aa, *vwork;
3764:   MPI_Comm    comm;
3765:   Mat_SeqAIJ *aij;
3766:   PetscBool   colflag, allcolumns = PETSC_FALSE;

3768:   PetscFunctionBegin;
3769:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3770:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
3771:   PetscCallMPI(MPI_Comm_size(comm, &size));

3773:   /* Check for special case: each processor gets entire matrix columns */
3774:   PetscCall(ISIdentity(iscol, &colflag));
3775:   PetscCall(ISGetLocalSize(iscol, &n));
3776:   if (colflag && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3777:   PetscCall(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));

3779:   if (call == MAT_REUSE_MATRIX) {
3780:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Mreuse));
3781:     PetscCheck(Mreuse, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3782:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_REUSE_MATRIX, allcolumns, &Mreuse));
3783:   } else {
3784:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, allcolumns, &Mreuse));
3785:   }

3787:   /*
3788:       m - number of local rows
3789:       n - number of columns (same on all processors)
3790:       rstart - first row in new global matrix generated
3791:   */
3792:   PetscCall(MatGetSize(Mreuse, &m, &n));
3793:   PetscCall(MatGetBlockSizes(Mreuse, &bs, &cbs));
3794:   if (call == MAT_INITIAL_MATRIX) {
3795:     aij = (Mat_SeqAIJ *)(Mreuse)->data;
3796:     ii  = aij->i;
3797:     jj  = aij->j;

3799:     /*
3800:         Determine the number of non-zeros in the diagonal and off-diagonal
3801:         portions of the matrix in order to do correct preallocation
3802:     */

3804:     /* first get start and end of "diagonal" columns */
3805:     if (csize == PETSC_DECIDE) {
3806:       PetscCall(ISGetSize(isrow, &mglobal));
3807:       if (mglobal == n) { /* square matrix */
3808:         nlocal = m;
3809:       } else {
3810:         nlocal = n / size + ((n % size) > rank);
3811:       }
3812:     } else {
3813:       nlocal = csize;
3814:     }
3815:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3816:     rstart = rend - nlocal;
3817:     PetscCheck(rank != size - 1 || rend == n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Local column sizes %" PetscInt_FMT " do not add up to total number of columns %" PetscInt_FMT, rend, n);

3819:     /* next, compute all the lengths */
3820:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3821:     olens = dlens + m;
3822:     for (i = 0; i < m; i++) {
3823:       jend = ii[i + 1] - ii[i];
3824:       olen = 0;
3825:       dlen = 0;
3826:       for (j = 0; j < jend; j++) {
3827:         if (*jj < rstart || *jj >= rend) olen++;
3828:         else dlen++;
3829:         jj++;
3830:       }
3831:       olens[i] = olen;
3832:       dlens[i] = dlen;
3833:     }
3834:     PetscCall(MatCreate(comm, &M));
3835:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, n));
3836:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3837:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3838:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3839:     PetscCall(PetscFree(dlens));
3840:   } else {
3841:     PetscInt ml, nl;

3843:     M = *newmat;
3844:     PetscCall(MatGetLocalSize(M, &ml, &nl));
3845:     PetscCheck(ml == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3846:     PetscCall(MatZeroEntries(M));
3847:     /*
3848:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3849:        rather than the slower MatSetValues().
3850:     */
3851:     M->was_assembled = PETSC_TRUE;
3852:     M->assembled     = PETSC_FALSE;
3853:   }
3854:   PetscCall(MatGetOwnershipRange(M, &rstart, &rend));
3855:   aij = (Mat_SeqAIJ *)(Mreuse)->data;
3856:   ii  = aij->i;
3857:   jj  = aij->j;

3859:   /* trigger copy to CPU if needed */
3860:   PetscCall(MatSeqAIJGetArrayRead(Mreuse, (const PetscScalar **)&aa));
3861:   for (i = 0; i < m; i++) {
3862:     row   = rstart + i;
3863:     nz    = ii[i + 1] - ii[i];
3864:     cwork = jj;
3865:     jj    = PetscSafePointerPlusOffset(jj, nz);
3866:     vwork = aa;
3867:     aa    = PetscSafePointerPlusOffset(aa, nz);
3868:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, cwork, vwork, INSERT_VALUES));
3869:   }
3870:   PetscCall(MatSeqAIJRestoreArrayRead(Mreuse, (const PetscScalar **)&aa));

3872:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3873:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
3874:   *newmat = M;

3876:   /* save submatrix used in processor for next request */
3877:   if (call == MAT_INITIAL_MATRIX) {
3878:     PetscCall(PetscObjectCompose((PetscObject)M, "SubMatrix", (PetscObject)Mreuse));
3879:     PetscCall(MatDestroy(&Mreuse));
3880:   }
3881:   PetscFunctionReturn(PETSC_SUCCESS);
3882: }

3884: static PetscErrorCode MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
3885: {
3886:   PetscInt        m, cstart, cend, j, nnz, i, d, *ld;
3887:   PetscInt       *d_nnz, *o_nnz, nnz_max = 0, rstart, ii;
3888:   const PetscInt *JJ;
3889:   PetscBool       nooffprocentries;
3890:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)B->data;

3892:   PetscFunctionBegin;
3893:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Ii[0] must be 0 it is %" PetscInt_FMT, Ii[0]);

3895:   PetscCall(PetscLayoutSetUp(B->rmap));
3896:   PetscCall(PetscLayoutSetUp(B->cmap));
3897:   m      = B->rmap->n;
3898:   cstart = B->cmap->rstart;
3899:   cend   = B->cmap->rend;
3900:   rstart = B->rmap->rstart;

3902:   PetscCall(PetscCalloc2(m, &d_nnz, m, &o_nnz));

3904:   if (PetscDefined(USE_DEBUG)) {
3905:     for (i = 0; i < m; i++) {
3906:       nnz = Ii[i + 1] - Ii[i];
3907:       JJ  = PetscSafePointerPlusOffset(J, Ii[i]);
3908:       PetscCheck(nnz >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local row %" PetscInt_FMT " has a negative %" PetscInt_FMT " number of columns", i, nnz);
3909:       PetscCheck(!nnz || !(JJ[0] < 0), PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Row %" PetscInt_FMT " starts with negative column index %" PetscInt_FMT, i, JJ[0]);
3910:       PetscCheck(!nnz || !(JJ[nnz - 1] >= B->cmap->N), PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Row %" PetscInt_FMT " ends with too large a column index %" PetscInt_FMT " (max allowed %" PetscInt_FMT ")", i, JJ[nnz - 1], B->cmap->N);
3911:     }
3912:   }

3914:   for (i = 0; i < m; i++) {
3915:     nnz     = Ii[i + 1] - Ii[i];
3916:     JJ      = PetscSafePointerPlusOffset(J, Ii[i]);
3917:     nnz_max = PetscMax(nnz_max, nnz);
3918:     d       = 0;
3919:     for (j = 0; j < nnz; j++) {
3920:       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3921:     }
3922:     d_nnz[i] = d;
3923:     o_nnz[i] = nnz - d;
3924:   }
3925:   PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
3926:   PetscCall(PetscFree2(d_nnz, o_nnz));

3928:   for (i = 0; i < m; i++) {
3929:     ii = i + rstart;
3930:     PetscCall(MatSetValues_MPIAIJ(B, 1, &ii, Ii[i + 1] - Ii[i], PetscSafePointerPlusOffset(J, Ii[i]), PetscSafePointerPlusOffset(v, Ii[i]), INSERT_VALUES));
3931:   }
3932:   nooffprocentries    = B->nooffprocentries;
3933:   B->nooffprocentries = PETSC_TRUE;
3934:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
3935:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
3936:   B->nooffprocentries = nooffprocentries;

3938:   /* count number of entries below block diagonal */
3939:   PetscCall(PetscFree(Aij->ld));
3940:   PetscCall(PetscCalloc1(m, &ld));
3941:   Aij->ld = ld;
3942:   for (i = 0; i < m; i++) {
3943:     nnz = Ii[i + 1] - Ii[i];
3944:     j   = 0;
3945:     while (j < nnz && J[j] < cstart) j++;
3946:     ld[i] = j;
3947:     if (J) J += nnz;
3948:   }

3950:   PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3951:   PetscFunctionReturn(PETSC_SUCCESS);
3952: }

3954: /*@
3955:   MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in `MATAIJ` format
3956:   (the default parallel PETSc format).

3958:   Collective

3960:   Input Parameters:
3961: + B - the matrix
3962: . i - the indices into `j` for the start of each local row (indices start with zero)
3963: . j - the column indices for each local row (indices start with zero)
3964: - v - optional values in the matrix

3966:   Level: developer

3968:   Notes:
3969:   The `i`, `j`, and `v` arrays ARE copied by this routine into the internal format used by PETSc;
3970:   thus you CANNOT change the matrix entries by changing the values of `v` after you have
3971:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

3973:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

3975:   A convenience routine for this functionality is `MatCreateMPIAIJWithArrays()`.

3977:   You can update the matrix with new numerical values using `MatUpdateMPIAIJWithArrays()` after this call if the column indices in `j` are sorted.

3979:   If you do **not** use `MatUpdateMPIAIJWithArrays()`, the column indices in `j` do not need to be sorted. If you will use
3980:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

3982:   The format which is used for the sparse matrix input, is equivalent to a
3983:   row-major ordering.. i.e for the following matrix, the input data expected is
3984:   as shown
3985: .vb
3986:         1 0 0
3987:         2 0 3     P0
3988:        -------
3989:         4 5 6     P1

3991:      Process0 [P0] rows_owned=[0,1]
3992:         i =  {0,1,3}  [size = nrow+1  = 2+1]
3993:         j =  {0,0,2}  [size = 3]
3994:         v =  {1,2,3}  [size = 3]

3996:      Process1 [P1] rows_owned=[2]
3997:         i =  {0,3}    [size = nrow+1  = 1+1]
3998:         j =  {0,1,2}  [size = 3]
3999:         v =  {4,5,6}  [size = 3]
4000: .ve

4002: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatCreateAIJ()`,
4003:           `MatCreateSeqAIJWithArrays()`, `MatCreateMPIAIJWithSplitArrays()`, `MatCreateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4004: @*/
4005: PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
4006: {
4007:   PetscFunctionBegin;
4008:   PetscTryMethod(B, "MatMPIAIJSetPreallocationCSR_C", (Mat, const PetscInt[], const PetscInt[], const PetscScalar[]), (B, i, j, v));
4009:   PetscFunctionReturn(PETSC_SUCCESS);
4010: }

4012: /*@C
4013:   MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in `MATMPIAIJ` format
4014:   (the default parallel PETSc format).  For good matrix assembly performance
4015:   the user should preallocate the matrix storage by setting the parameters
4016:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4018:   Collective

4020:   Input Parameters:
4021: + B     - the matrix
4022: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4023:            (same value is used for all local rows)
4024: . d_nnz - array containing the number of nonzeros in the various rows of the
4025:            DIAGONAL portion of the local submatrix (possibly different for each row)
4026:            or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `d_nz` is used to specify the nonzero structure.
4027:            The size of this array is equal to the number of local rows, i.e 'm'.
4028:            For matrices that will be factored, you must leave room for (and set)
4029:            the diagonal entry even if it is zero.
4030: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4031:            submatrix (same value is used for all local rows).
4032: - o_nnz - array containing the number of nonzeros in the various rows of the
4033:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4034:            each row) or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `o_nz` is used to specify the nonzero
4035:            structure. The size of this array is equal to the number
4036:            of local rows, i.e 'm'.

4038:   Example Usage:
4039:   Consider the following 8x8 matrix with 34 non-zero values, that is
4040:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4041:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4042:   as follows

4044: .vb
4045:             1  2  0  |  0  3  0  |  0  4
4046:     Proc0   0  5  6  |  7  0  0  |  8  0
4047:             9  0 10  | 11  0  0  | 12  0
4048:     -------------------------------------
4049:            13  0 14  | 15 16 17  |  0  0
4050:     Proc1   0 18  0  | 19 20 21  |  0  0
4051:             0  0  0  | 22 23  0  | 24  0
4052:     -------------------------------------
4053:     Proc2  25 26 27  |  0  0 28  | 29  0
4054:            30  0  0  | 31 32 33  |  0 34
4055: .ve

4057:   This can be represented as a collection of submatrices as
4058: .vb
4059:       A B C
4060:       D E F
4061:       G H I
4062: .ve

4064:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4065:   owned by proc1, G,H,I are owned by proc2.

4067:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4068:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4069:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4071:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4072:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4073:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4074:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4075:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4076:   matrix, ans [DF] as another `MATSEQAIJ` matrix.

4078:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4079:   allocated for every row of the local diagonal submatrix, and `o_nz`
4080:   storage locations are allocated for every row of the OFF-DIAGONAL submat.
4081:   One way to choose `d_nz` and `o_nz` is to use the max nonzerors per local
4082:   rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4083:   In this case, the values of `d_nz`, `o_nz` are
4084: .vb
4085:      proc0  dnz = 2, o_nz = 2
4086:      proc1  dnz = 3, o_nz = 2
4087:      proc2  dnz = 1, o_nz = 4
4088: .ve
4089:   We are allocating `m`*(`d_nz`+`o_nz`) storage locations for every proc. This
4090:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4091:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4092:   34 values.

4094:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4095:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4096:   In the above case the values for `d_nnz`, `o_nnz` are
4097: .vb
4098:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4099:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4100:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4101: .ve
4102:   Here the space allocated is sum of all the above values i.e 34, and
4103:   hence pre-allocation is perfect.

4105:   Level: intermediate

4107:   Notes:
4108:   If the *_nnz parameter is given then the *_nz parameter is ignored

4110:   The `MATAIJ` format, also called compressed row storage (CSR), is compatible with standard Fortran
4111:   storage.  The stored row and column indices begin with zero.
4112:   See [Sparse Matrices](sec_matsparse) for details.

4114:   The parallel matrix is partitioned such that the first m0 rows belong to
4115:   process 0, the next m1 rows belong to process 1, the next m2 rows belong
4116:   to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.

4118:   The DIAGONAL portion of the local submatrix of a processor can be defined
4119:   as the submatrix which is obtained by extraction the part corresponding to
4120:   the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4121:   first row that belongs to the processor, r2 is the last row belonging to
4122:   the this processor, and c1-c2 is range of indices of the local part of a
4123:   vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4124:   common case of a square matrix, the row and column ranges are the same and
4125:   the DIAGONAL part is also square. The remaining portion of the local
4126:   submatrix (mxN) constitute the OFF-DIAGONAL portion.

4128:   If `o_nnz` and `d_nnz` are specified, then `o_nz` and `d_nz` are ignored.

4130:   You can call `MatGetInfo()` to get information on how effective the preallocation was;
4131:   for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4132:   You can also run with the option `-info` and look for messages with the string
4133:   malloc in them to see if additional memory allocation was needed.

4135: .seealso: [](ch_matrices), `Mat`, [Sparse Matrices](sec_matsparse), `MATMPIAIJ`, `MATAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatCreateAIJ()`, `MatMPIAIJSetPreallocationCSR()`,
4136:           `MatGetInfo()`, `PetscSplitOwnership()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4137: @*/
4138: PetscErrorCode MatMPIAIJSetPreallocation(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
4139: {
4140:   PetscFunctionBegin;
4143:   PetscTryMethod(B, "MatMPIAIJSetPreallocation_C", (Mat, PetscInt, const PetscInt[], PetscInt, const PetscInt[]), (B, d_nz, d_nnz, o_nz, o_nnz));
4144:   PetscFunctionReturn(PETSC_SUCCESS);
4145: }

4147: /*@
4148:   MatCreateMPIAIJWithArrays - creates a `MATMPIAIJ` matrix using arrays that contain in standard
4149:   CSR format for the local rows.

4151:   Collective

4153:   Input Parameters:
4154: + comm - MPI communicator
4155: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
4156: . n    - This value should be the same as the local size used in creating the
4157:          x vector for the matrix-vector product $ y = Ax$. (or `PETSC_DECIDE` to have
4158:          calculated if `N` is given) For square matrices n is almost always `m`.
4159: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
4160: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
4161: . i    - row indices (of length m+1); that is i[0] = 0, i[row] = i[row-1] + number of elements in that row of the matrix
4162: . j    - global column indices
4163: - a    - optional matrix values

4165:   Output Parameter:
4166: . mat - the matrix

4168:   Level: intermediate

4170:   Notes:
4171:   The `i`, `j`, and `a` arrays ARE copied by this routine into the internal format used by PETSc;
4172:   thus you CANNOT change the matrix entries by changing the values of `a[]` after you have
4173:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

4175:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4177:   Once you have created the matrix you can update it with new numerical values using `MatUpdateMPIAIJWithArray()`

4179:   If you do **not** use `MatUpdateMPIAIJWithArray()`, the column indices in `j` do not need to be sorted. If you will use
4180:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

4182:   The format which is used for the sparse matrix input, is equivalent to a
4183:   row-major ordering, i.e., for the following matrix, the input data expected is
4184:   as shown
4185: .vb
4186:         1 0 0
4187:         2 0 3     P0
4188:        -------
4189:         4 5 6     P1

4191:      Process0 [P0] rows_owned=[0,1]
4192:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4193:         j =  {0,0,2}  [size = 3]
4194:         v =  {1,2,3}  [size = 3]

4196:      Process1 [P1] rows_owned=[2]
4197:         i =  {0,3}    [size = nrow+1  = 1+1]
4198:         j =  {0,1,2}  [size = 3]
4199:         v =  {4,5,6}  [size = 3]
4200: .ve

4202: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4203:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4204: @*/
4205: PetscErrorCode MatCreateMPIAIJWithArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt i[], const PetscInt j[], const PetscScalar a[], Mat *mat)
4206: {
4207:   PetscFunctionBegin;
4208:   PetscCheck(!i || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4209:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4210:   PetscCall(MatCreate(comm, mat));
4211:   PetscCall(MatSetSizes(*mat, m, n, M, N));
4212:   /* PetscCall(MatSetBlockSizes(M,bs,cbs)); */
4213:   PetscCall(MatSetType(*mat, MATMPIAIJ));
4214:   PetscCall(MatMPIAIJSetPreallocationCSR(*mat, i, j, a));
4215:   PetscFunctionReturn(PETSC_SUCCESS);
4216: }

4218: /*@
4219:   MatUpdateMPIAIJWithArrays - updates a `MATMPIAIJ` matrix using arrays that contain in standard
4220:   CSR format for the local rows. Only the numerical values are updated the other arrays must be identical to what was passed
4221:   from `MatCreateMPIAIJWithArrays()`

4223:   Deprecated: Use `MatUpdateMPIAIJWithArray()`

4225:   Collective

4227:   Input Parameters:
4228: + mat - the matrix
4229: . m   - number of local rows (Cannot be `PETSC_DECIDE`)
4230: . n   - This value should be the same as the local size used in creating the
4231:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4232:        calculated if N is given) For square matrices n is almost always m.
4233: . M   - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4234: . N   - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4235: . Ii  - row indices; that is Ii[0] = 0, Ii[row] = Ii[row-1] + number of elements in that row of the matrix
4236: . J   - column indices
4237: - v   - matrix values

4239:   Level: deprecated

4241: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4242:           `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4243: @*/
4244: PetscErrorCode MatUpdateMPIAIJWithArrays(Mat mat, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
4245: {
4246:   PetscInt        nnz, i;
4247:   PetscBool       nooffprocentries;
4248:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4249:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4250:   PetscScalar    *ad, *ao;
4251:   PetscInt        ldi, Iii, md;
4252:   const PetscInt *Adi = Ad->i;
4253:   PetscInt       *ld  = Aij->ld;

4255:   PetscFunctionBegin;
4256:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4257:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4258:   PetscCheck(m == mat->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of rows cannot change from call to MatUpdateMPIAIJWithArrays()");
4259:   PetscCheck(n == mat->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of columns cannot change from call to MatUpdateMPIAIJWithArrays()");

4261:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4262:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));

4264:   for (i = 0; i < m; i++) {
4265:     if (PetscDefined(USE_DEBUG)) {
4266:       for (PetscInt j = Ii[i] + 1; j < Ii[i + 1]; ++j) {
4267:         PetscCheck(J[j] >= J[j - 1], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column entry number %" PetscInt_FMT " (actual column %" PetscInt_FMT ") in row %" PetscInt_FMT " is not sorted", j - Ii[i], J[j], i);
4268:         PetscCheck(J[j] != J[j - 1], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column entry number %" PetscInt_FMT " (actual column %" PetscInt_FMT ") in row %" PetscInt_FMT " is identical to previous entry", j - Ii[i], J[j], i);
4269:       }
4270:     }
4271:     nnz = Ii[i + 1] - Ii[i];
4272:     Iii = Ii[i];
4273:     ldi = ld[i];
4274:     md  = Adi[i + 1] - Adi[i];
4275:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4276:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4277:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4278:     ad += md;
4279:     ao += nnz - md;
4280:   }
4281:   nooffprocentries      = mat->nooffprocentries;
4282:   mat->nooffprocentries = PETSC_TRUE;
4283:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4284:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4285:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4286:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4287:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4288:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4289:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4290:   mat->nooffprocentries = nooffprocentries;
4291:   PetscFunctionReturn(PETSC_SUCCESS);
4292: }

4294: /*@
4295:   MatUpdateMPIAIJWithArray - updates an `MATMPIAIJ` matrix using an array that contains the nonzero values

4297:   Collective

4299:   Input Parameters:
4300: + mat - the matrix
4301: - v   - matrix values, stored by row

4303:   Level: intermediate

4305:   Notes:
4306:   The matrix must have been obtained with `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()`

4308:   The column indices in the call to `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()` must have been sorted for this call to work correctly

4310: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4311:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4312: @*/
4313: PetscErrorCode MatUpdateMPIAIJWithArray(Mat mat, const PetscScalar v[])
4314: {
4315:   PetscInt        nnz, i, m;
4316:   PetscBool       nooffprocentries;
4317:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4318:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4319:   Mat_SeqAIJ     *Ao  = (Mat_SeqAIJ *)Aij->B->data;
4320:   PetscScalar    *ad, *ao;
4321:   const PetscInt *Adi = Ad->i, *Adj = Ao->i;
4322:   PetscInt        ldi, Iii, md;
4323:   PetscInt       *ld = Aij->ld;

4325:   PetscFunctionBegin;
4326:   m = mat->rmap->n;

4328:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4329:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));
4330:   Iii = 0;
4331:   for (i = 0; i < m; i++) {
4332:     nnz = Adi[i + 1] - Adi[i] + Adj[i + 1] - Adj[i];
4333:     ldi = ld[i];
4334:     md  = Adi[i + 1] - Adi[i];
4335:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4336:     ad += md;
4337:     if (ao) {
4338:       PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4339:       PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4340:       ao += nnz - md;
4341:     }
4342:     Iii += nnz;
4343:   }
4344:   nooffprocentries      = mat->nooffprocentries;
4345:   mat->nooffprocentries = PETSC_TRUE;
4346:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4347:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4348:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4349:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4350:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4351:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4352:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4353:   mat->nooffprocentries = nooffprocentries;
4354:   PetscFunctionReturn(PETSC_SUCCESS);
4355: }

4357: /*@C
4358:   MatCreateAIJ - Creates a sparse parallel matrix in `MATAIJ` format
4359:   (the default parallel PETSc format).  For good matrix assembly performance
4360:   the user should preallocate the matrix storage by setting the parameters
4361:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4363:   Collective

4365:   Input Parameters:
4366: + comm  - MPI communicator
4367: . m     - number of local rows (or `PETSC_DECIDE` to have calculated if M is given)
4368:           This value should be the same as the local size used in creating the
4369:           y vector for the matrix-vector product y = Ax.
4370: . n     - This value should be the same as the local size used in creating the
4371:           x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4372:           calculated if N is given) For square matrices n is almost always m.
4373: . M     - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4374: . N     - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4375: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4376:           (same value is used for all local rows)
4377: . d_nnz - array containing the number of nonzeros in the various rows of the
4378:           DIAGONAL portion of the local submatrix (possibly different for each row)
4379:           or `NULL`, if `d_nz` is used to specify the nonzero structure.
4380:           The size of this array is equal to the number of local rows, i.e 'm'.
4381: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4382:           submatrix (same value is used for all local rows).
4383: - o_nnz - array containing the number of nonzeros in the various rows of the
4384:           OFF-DIAGONAL portion of the local submatrix (possibly different for
4385:           each row) or `NULL`, if `o_nz` is used to specify the nonzero
4386:           structure. The size of this array is equal to the number
4387:           of local rows, i.e 'm'.

4389:   Output Parameter:
4390: . A - the matrix

4392:   Options Database Keys:
4393: + -mat_no_inode                     - Do not use inodes
4394: . -mat_inode_limit <limit>          - Sets inode limit (max limit=5)
4395: - -matmult_vecscatter_view <viewer> - View the vecscatter (i.e., communication pattern) used in `MatMult()` of sparse parallel matrices.
4396:                                       See viewer types in manual of `MatView()`. Of them, ascii_matlab, draw or binary cause the `VecScatter`
4397:                                       to be viewed as a matrix. Entry (i,j) is the size of message (in bytes) rank i sends to rank j in one `MatMult()` call.

4399:   Level: intermediate

4401:   Notes:
4402:   It is recommended that one use `MatCreateFromOptions()` or the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
4403:   MatXXXXSetPreallocation() paradigm instead of this routine directly.
4404:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

4406:   If the *_nnz parameter is given then the *_nz parameter is ignored

4408:   The `m`,`n`,`M`,`N` parameters specify the size of the matrix, and its partitioning across
4409:   processors, while `d_nz`,`d_nnz`,`o_nz`,`o_nnz` parameters specify the approximate
4410:   storage requirements for this matrix.

4412:   If `PETSC_DECIDE` or  `PETSC_DETERMINE` is used for a particular argument on one
4413:   processor than it must be used on all processors that share the object for
4414:   that argument.

4416:   If `m` and `n` are not `PETSC_DECIDE`, then the values determine the `PetscLayout` of the matrix and the ranges returned by
4417:   `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`, and `MatGetOwnershipRangesColumn()`.

4419:   The user MUST specify either the local or global matrix dimensions
4420:   (possibly both).

4422:   The parallel matrix is partitioned across processors such that the
4423:   first `m0` rows belong to process 0, the next `m1` rows belong to
4424:   process 1, the next `m2` rows belong to process 2, etc., where
4425:   `m0`, `m1`, `m2`... are the input parameter `m` on each MPI process. I.e., each MPI process stores
4426:   values corresponding to [m x N] submatrix.

4428:   The columns are logically partitioned with the n0 columns belonging
4429:   to 0th partition, the next n1 columns belonging to the next
4430:   partition etc.. where n0,n1,n2... are the input parameter 'n'.

4432:   The DIAGONAL portion of the local submatrix on any given processor
4433:   is the submatrix corresponding to the rows and columns m,n
4434:   corresponding to the given processor. i.e diagonal matrix on
4435:   process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4436:   etc. The remaining portion of the local submatrix [m x (N-n)]
4437:   constitute the OFF-DIAGONAL portion. The example below better
4438:   illustrates this concept.

4440:   For a square global matrix we define each processor's diagonal portion
4441:   to be its local rows and the corresponding columns (a square submatrix);
4442:   each processor's off-diagonal portion encompasses the remainder of the
4443:   local matrix (a rectangular submatrix).

4445:   If `o_nnz`, `d_nnz` are specified, then `o_nz`, and `d_nz` are ignored.

4447:   When calling this routine with a single process communicator, a matrix of
4448:   type `MATSEQAIJ` is returned.  If a matrix of type `MATMPIAIJ` is desired for this
4449:   type of communicator, use the construction mechanism
4450: .vb
4451:   MatCreate(..., &A);
4452:   MatSetType(A, MATMPIAIJ);
4453:   MatSetSizes(A, m, n, M, N);
4454:   MatMPIAIJSetPreallocation(A, ...);
4455: .ve

4457:   By default, this format uses inodes (identical nodes) when possible.
4458:   We search for consecutive rows with the same nonzero structure, thereby
4459:   reusing matrix information to achieve increased efficiency.

4461:   Example Usage:
4462:   Consider the following 8x8 matrix with 34 non-zero values, that is
4463:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4464:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4465:   as follows

4467: .vb
4468:             1  2  0  |  0  3  0  |  0  4
4469:     Proc0   0  5  6  |  7  0  0  |  8  0
4470:             9  0 10  | 11  0  0  | 12  0
4471:     -------------------------------------
4472:            13  0 14  | 15 16 17  |  0  0
4473:     Proc1   0 18  0  | 19 20 21  |  0  0
4474:             0  0  0  | 22 23  0  | 24  0
4475:     -------------------------------------
4476:     Proc2  25 26 27  |  0  0 28  | 29  0
4477:            30  0  0  | 31 32 33  |  0 34
4478: .ve

4480:   This can be represented as a collection of submatrices as

4482: .vb
4483:       A B C
4484:       D E F
4485:       G H I
4486: .ve

4488:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4489:   owned by proc1, G,H,I are owned by proc2.

4491:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4492:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4493:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4495:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4496:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4497:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4498:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4499:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4500:   matrix, ans [DF] as another SeqAIJ matrix.

4502:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4503:   allocated for every row of the local diagonal submatrix, and `o_nz`
4504:   storage locations are allocated for every row of the OFF-DIAGONAL submat.
4505:   One way to choose `d_nz` and `o_nz` is to use the max nonzerors per local
4506:   rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4507:   In this case, the values of `d_nz`,`o_nz` are
4508: .vb
4509:      proc0  dnz = 2, o_nz = 2
4510:      proc1  dnz = 3, o_nz = 2
4511:      proc2  dnz = 1, o_nz = 4
4512: .ve
4513:   We are allocating m*(`d_nz`+`o_nz`) storage locations for every proc. This
4514:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4515:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4516:   34 values.

4518:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4519:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4520:   In the above case the values for d_nnz,o_nnz are
4521: .vb
4522:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4523:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4524:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4525: .ve
4526:   Here the space allocated is sum of all the above values i.e 34, and
4527:   hence pre-allocation is perfect.

4529: .seealso: [](ch_matrices), `Mat`, [Sparse Matrix Creation](sec_matsparse), `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4530:           `MATMPIAIJ`, `MatCreateMPIAIJWithArrays()`, `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`,
4531:           `MatGetOwnershipRangesColumn()`, `PetscLayout`
4532: @*/
4533: PetscErrorCode MatCreateAIJ(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[], Mat *A)
4534: {
4535:   PetscMPIInt size;

4537:   PetscFunctionBegin;
4538:   PetscCall(MatCreate(comm, A));
4539:   PetscCall(MatSetSizes(*A, m, n, M, N));
4540:   PetscCallMPI(MPI_Comm_size(comm, &size));
4541:   if (size > 1) {
4542:     PetscCall(MatSetType(*A, MATMPIAIJ));
4543:     PetscCall(MatMPIAIJSetPreallocation(*A, d_nz, d_nnz, o_nz, o_nnz));
4544:   } else {
4545:     PetscCall(MatSetType(*A, MATSEQAIJ));
4546:     PetscCall(MatSeqAIJSetPreallocation(*A, d_nz, d_nnz));
4547:   }
4548:   PetscFunctionReturn(PETSC_SUCCESS);
4549: }

4551: /*MC
4552:     MatMPIAIJGetSeqAIJF90 - Returns the local pieces of this distributed matrix

4554:     Synopsis:
4555:     MatMPIAIJGetSeqAIJF90(Mat A, Mat Ad, Mat Ao, {PetscInt, pointer :: colmap(:)},integer ierr)

4557:     Not Collective

4559:     Input Parameter:
4560: .   A - the `MATMPIAIJ` matrix

4562:     Output Parameters:
4563: +   Ad - the diagonal portion of the matrix
4564: .   Ao - the off-diagonal portion of the matrix
4565: .   colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix
4566: -   ierr - error code

4568:      Level: advanced

4570:     Note:
4571:     Use  `MatMPIAIJRestoreSeqAIJF90()` when you no longer need access to the matrices and `colmap`

4573: .seealso: [](ch_matrices), `Mat`, [](sec_fortranarrays), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJ()`, `MatMPIAIJRestoreSeqAIJF90()`
4574: M*/

4576: /*MC
4577:     MatMPIAIJRestoreSeqAIJF90 - call after `MatMPIAIJGetSeqAIJF90()` when you no longer need access to the matrices and `colmap`

4579:     Synopsis:
4580:     MatMPIAIJRestoreSeqAIJF90(Mat A, Mat Ad, Mat Ao, {PetscInt, pointer :: colmap(:)},integer ierr)

4582:     Not Collective

4584:     Input Parameters:
4585: +   A - the `MATMPIAIJ` matrix
4586: .   Ad - the diagonal portion of the matrix
4587: .   Ao - the off-diagonal portion of the matrix
4588: .   colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix
4589: -   ierr - error code

4591:      Level: advanced

4593: .seealso: [](ch_matrices), `Mat`, [](sec_fortranarrays), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJ()`, `MatMPIAIJGetSeqAIJF90()`
4594: M*/

4596: /*@C
4597:   MatMPIAIJGetSeqAIJ - Returns the local pieces of this distributed matrix

4599:   Not Collective

4601:   Input Parameter:
4602: . A - The `MATMPIAIJ` matrix

4604:   Output Parameters:
4605: + Ad     - The local diagonal block as a `MATSEQAIJ` matrix
4606: . Ao     - The local off-diagonal block as a `MATSEQAIJ` matrix
4607: - colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix

4609:   Level: intermediate

4611:   Note:
4612:   The rows in `Ad` and `Ao` are in [0, Nr), where Nr is the number of local rows on this process. The columns
4613:   in `Ad` are in [0, Nc) where Nc is the number of local columns. The columns are `Ao` are in [0, Nco), where Nco is
4614:   the number of nonzero columns in the local off-diagonal piece of the matrix `A`. The array colmap maps these
4615:   local column numbers to global column numbers in the original matrix.

4617:   Fortran Notes:
4618:   `MatMPIAIJGetSeqAIJ()` Fortran binding is deprecated (since PETSc 3.19), use `MatMPIAIJGetSeqAIJF90()`

4620: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJF90()`, `MatMPIAIJRestoreSeqAIJF90()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`, `MatCreateAIJ()`, `MATSEQAIJ`
4621: @*/
4622: PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A, Mat *Ad, Mat *Ao, const PetscInt *colmap[])
4623: {
4624:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
4625:   PetscBool   flg;

4627:   PetscFunctionBegin;
4628:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &flg));
4629:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "This function requires a MATMPIAIJ matrix as input");
4630:   if (Ad) *Ad = a->A;
4631:   if (Ao) *Ao = a->B;
4632:   if (colmap) *colmap = a->garray;
4633:   PetscFunctionReturn(PETSC_SUCCESS);
4634: }

4636: PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm, Mat inmat, PetscInt n, MatReuse scall, Mat *outmat)
4637: {
4638:   PetscInt     m, N, i, rstart, nnz, Ii;
4639:   PetscInt    *indx;
4640:   PetscScalar *values;
4641:   MatType      rootType;

4643:   PetscFunctionBegin;
4644:   PetscCall(MatGetSize(inmat, &m, &N));
4645:   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
4646:     PetscInt *dnz, *onz, sum, bs, cbs;

4648:     if (n == PETSC_DECIDE) PetscCall(PetscSplitOwnership(comm, &n, &N));
4649:     /* Check sum(n) = N */
4650:     PetscCall(MPIU_Allreduce(&n, &sum, 1, MPIU_INT, MPI_SUM, comm));
4651:     PetscCheck(sum == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Sum of local columns %" PetscInt_FMT " != global columns %" PetscInt_FMT, sum, N);

4653:     PetscCallMPI(MPI_Scan(&m, &rstart, 1, MPIU_INT, MPI_SUM, comm));
4654:     rstart -= m;

4656:     MatPreallocateBegin(comm, m, n, dnz, onz);
4657:     for (i = 0; i < m; i++) {
4658:       PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4659:       PetscCall(MatPreallocateSet(i + rstart, nnz, indx, dnz, onz));
4660:       PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4661:     }

4663:     PetscCall(MatCreate(comm, outmat));
4664:     PetscCall(MatSetSizes(*outmat, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4665:     PetscCall(MatGetBlockSizes(inmat, &bs, &cbs));
4666:     PetscCall(MatSetBlockSizes(*outmat, bs, cbs));
4667:     PetscCall(MatGetRootType_Private(inmat, &rootType));
4668:     PetscCall(MatSetType(*outmat, rootType));
4669:     PetscCall(MatSeqAIJSetPreallocation(*outmat, 0, dnz));
4670:     PetscCall(MatMPIAIJSetPreallocation(*outmat, 0, dnz, 0, onz));
4671:     MatPreallocateEnd(dnz, onz);
4672:     PetscCall(MatSetOption(*outmat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
4673:   }

4675:   /* numeric phase */
4676:   PetscCall(MatGetOwnershipRange(*outmat, &rstart, NULL));
4677:   for (i = 0; i < m; i++) {
4678:     PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4679:     Ii = i + rstart;
4680:     PetscCall(MatSetValues(*outmat, 1, &Ii, nnz, indx, values, INSERT_VALUES));
4681:     PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4682:   }
4683:   PetscCall(MatAssemblyBegin(*outmat, MAT_FINAL_ASSEMBLY));
4684:   PetscCall(MatAssemblyEnd(*outmat, MAT_FINAL_ASSEMBLY));
4685:   PetscFunctionReturn(PETSC_SUCCESS);
4686: }

4688: static PetscErrorCode MatDestroy_MPIAIJ_SeqsToMPI(void *data)
4689: {
4690:   Mat_Merge_SeqsToMPI *merge = (Mat_Merge_SeqsToMPI *)data;

4692:   PetscFunctionBegin;
4693:   if (!merge) PetscFunctionReturn(PETSC_SUCCESS);
4694:   PetscCall(PetscFree(merge->id_r));
4695:   PetscCall(PetscFree(merge->len_s));
4696:   PetscCall(PetscFree(merge->len_r));
4697:   PetscCall(PetscFree(merge->bi));
4698:   PetscCall(PetscFree(merge->bj));
4699:   PetscCall(PetscFree(merge->buf_ri[0]));
4700:   PetscCall(PetscFree(merge->buf_ri));
4701:   PetscCall(PetscFree(merge->buf_rj[0]));
4702:   PetscCall(PetscFree(merge->buf_rj));
4703:   PetscCall(PetscFree(merge->coi));
4704:   PetscCall(PetscFree(merge->coj));
4705:   PetscCall(PetscFree(merge->owners_co));
4706:   PetscCall(PetscLayoutDestroy(&merge->rowmap));
4707:   PetscCall(PetscFree(merge));
4708:   PetscFunctionReturn(PETSC_SUCCESS);
4709: }

4711: #include <../src/mat/utils/freespace.h>
4712: #include <petscbt.h>

4714: PetscErrorCode MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat, Mat mpimat)
4715: {
4716:   MPI_Comm             comm;
4717:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)seqmat->data;
4718:   PetscMPIInt          size, rank, taga, *len_s;
4719:   PetscInt             N = mpimat->cmap->N, i, j, *owners, *ai = a->i, *aj;
4720:   PetscInt             proc, m;
4721:   PetscInt           **buf_ri, **buf_rj;
4722:   PetscInt             k, anzi, *bj_i, *bi, *bj, arow, bnzi, nextaj;
4723:   PetscInt             nrows, **buf_ri_k, **nextrow, **nextai;
4724:   MPI_Request         *s_waits, *r_waits;
4725:   MPI_Status          *status;
4726:   const MatScalar     *aa, *a_a;
4727:   MatScalar          **abuf_r, *ba_i;
4728:   Mat_Merge_SeqsToMPI *merge;
4729:   PetscContainer       container;

4731:   PetscFunctionBegin;
4732:   PetscCall(PetscObjectGetComm((PetscObject)mpimat, &comm));
4733:   PetscCall(PetscLogEventBegin(MAT_Seqstompinum, seqmat, 0, 0, 0));

4735:   PetscCallMPI(MPI_Comm_size(comm, &size));
4736:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4738:   PetscCall(PetscObjectQuery((PetscObject)mpimat, "MatMergeSeqsToMPI", (PetscObject *)&container));
4739:   PetscCheck(container, PetscObjectComm((PetscObject)mpimat), PETSC_ERR_PLIB, "Mat not created from MatCreateMPIAIJSumSeqAIJSymbolic");
4740:   PetscCall(PetscContainerGetPointer(container, (void **)&merge));
4741:   PetscCall(MatSeqAIJGetArrayRead(seqmat, &a_a));
4742:   aa = a_a;

4744:   bi     = merge->bi;
4745:   bj     = merge->bj;
4746:   buf_ri = merge->buf_ri;
4747:   buf_rj = merge->buf_rj;

4749:   PetscCall(PetscMalloc1(size, &status));
4750:   owners = merge->rowmap->range;
4751:   len_s  = merge->len_s;

4753:   /* send and recv matrix values */
4754:   PetscCall(PetscObjectGetNewTag((PetscObject)mpimat, &taga));
4755:   PetscCall(PetscPostIrecvScalar(comm, taga, merge->nrecv, merge->id_r, merge->len_r, &abuf_r, &r_waits));

4757:   PetscCall(PetscMalloc1(merge->nsend + 1, &s_waits));
4758:   for (proc = 0, k = 0; proc < size; proc++) {
4759:     if (!len_s[proc]) continue;
4760:     i = owners[proc];
4761:     PetscCallMPI(MPI_Isend(aa + ai[i], len_s[proc], MPIU_MATSCALAR, proc, taga, comm, s_waits + k));
4762:     k++;
4763:   }

4765:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, r_waits, status));
4766:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, s_waits, status));
4767:   PetscCall(PetscFree(status));

4769:   PetscCall(PetscFree(s_waits));
4770:   PetscCall(PetscFree(r_waits));

4772:   /* insert mat values of mpimat */
4773:   PetscCall(PetscMalloc1(N, &ba_i));
4774:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4776:   for (k = 0; k < merge->nrecv; k++) {
4777:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4778:     nrows       = *buf_ri_k[k];
4779:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4780:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4781:   }

4783:   /* set values of ba */
4784:   m = merge->rowmap->n;
4785:   for (i = 0; i < m; i++) {
4786:     arow = owners[rank] + i;
4787:     bj_i = bj + bi[i]; /* col indices of the i-th row of mpimat */
4788:     bnzi = bi[i + 1] - bi[i];
4789:     PetscCall(PetscArrayzero(ba_i, bnzi));

4791:     /* add local non-zero vals of this proc's seqmat into ba */
4792:     anzi   = ai[arow + 1] - ai[arow];
4793:     aj     = a->j + ai[arow];
4794:     aa     = a_a + ai[arow];
4795:     nextaj = 0;
4796:     for (j = 0; nextaj < anzi; j++) {
4797:       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4798:         ba_i[j] += aa[nextaj++];
4799:       }
4800:     }

4802:     /* add received vals into ba */
4803:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4804:       /* i-th row */
4805:       if (i == *nextrow[k]) {
4806:         anzi   = *(nextai[k] + 1) - *nextai[k];
4807:         aj     = buf_rj[k] + *nextai[k];
4808:         aa     = abuf_r[k] + *nextai[k];
4809:         nextaj = 0;
4810:         for (j = 0; nextaj < anzi; j++) {
4811:           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4812:             ba_i[j] += aa[nextaj++];
4813:           }
4814:         }
4815:         nextrow[k]++;
4816:         nextai[k]++;
4817:       }
4818:     }
4819:     PetscCall(MatSetValues(mpimat, 1, &arow, bnzi, bj_i, ba_i, INSERT_VALUES));
4820:   }
4821:   PetscCall(MatSeqAIJRestoreArrayRead(seqmat, &a_a));
4822:   PetscCall(MatAssemblyBegin(mpimat, MAT_FINAL_ASSEMBLY));
4823:   PetscCall(MatAssemblyEnd(mpimat, MAT_FINAL_ASSEMBLY));

4825:   PetscCall(PetscFree(abuf_r[0]));
4826:   PetscCall(PetscFree(abuf_r));
4827:   PetscCall(PetscFree(ba_i));
4828:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));
4829:   PetscCall(PetscLogEventEnd(MAT_Seqstompinum, seqmat, 0, 0, 0));
4830:   PetscFunctionReturn(PETSC_SUCCESS);
4831: }

4833: PetscErrorCode MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, Mat *mpimat)
4834: {
4835:   Mat                  B_mpi;
4836:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)seqmat->data;
4837:   PetscMPIInt          size, rank, tagi, tagj, *len_s, *len_si, *len_ri;
4838:   PetscInt           **buf_rj, **buf_ri, **buf_ri_k;
4839:   PetscInt             M = seqmat->rmap->n, N = seqmat->cmap->n, i, *owners, *ai = a->i, *aj = a->j;
4840:   PetscInt             len, proc, *dnz, *onz, bs, cbs;
4841:   PetscInt             k, anzi, *bi, *bj, *lnk, nlnk, arow, bnzi;
4842:   PetscInt             nrows, *buf_s, *buf_si, *buf_si_i, **nextrow, **nextai;
4843:   MPI_Request         *si_waits, *sj_waits, *ri_waits, *rj_waits;
4844:   MPI_Status          *status;
4845:   PetscFreeSpaceList   free_space = NULL, current_space = NULL;
4846:   PetscBT              lnkbt;
4847:   Mat_Merge_SeqsToMPI *merge;
4848:   PetscContainer       container;

4850:   PetscFunctionBegin;
4851:   PetscCall(PetscLogEventBegin(MAT_Seqstompisym, seqmat, 0, 0, 0));

4853:   /* make sure it is a PETSc comm */
4854:   PetscCall(PetscCommDuplicate(comm, &comm, NULL));
4855:   PetscCallMPI(MPI_Comm_size(comm, &size));
4856:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4858:   PetscCall(PetscNew(&merge));
4859:   PetscCall(PetscMalloc1(size, &status));

4861:   /* determine row ownership */
4862:   PetscCall(PetscLayoutCreate(comm, &merge->rowmap));
4863:   PetscCall(PetscLayoutSetLocalSize(merge->rowmap, m));
4864:   PetscCall(PetscLayoutSetSize(merge->rowmap, M));
4865:   PetscCall(PetscLayoutSetBlockSize(merge->rowmap, 1));
4866:   PetscCall(PetscLayoutSetUp(merge->rowmap));
4867:   PetscCall(PetscMalloc1(size, &len_si));
4868:   PetscCall(PetscMalloc1(size, &merge->len_s));

4870:   m      = merge->rowmap->n;
4871:   owners = merge->rowmap->range;

4873:   /* determine the number of messages to send, their lengths */
4874:   len_s = merge->len_s;

4876:   len          = 0; /* length of buf_si[] */
4877:   merge->nsend = 0;
4878:   for (proc = 0; proc < size; proc++) {
4879:     len_si[proc] = 0;
4880:     if (proc == rank) {
4881:       len_s[proc] = 0;
4882:     } else {
4883:       len_si[proc] = owners[proc + 1] - owners[proc] + 1;
4884:       len_s[proc]  = ai[owners[proc + 1]] - ai[owners[proc]]; /* num of rows to be sent to [proc] */
4885:     }
4886:     if (len_s[proc]) {
4887:       merge->nsend++;
4888:       nrows = 0;
4889:       for (i = owners[proc]; i < owners[proc + 1]; i++) {
4890:         if (ai[i + 1] > ai[i]) nrows++;
4891:       }
4892:       len_si[proc] = 2 * (nrows + 1);
4893:       len += len_si[proc];
4894:     }
4895:   }

4897:   /* determine the number and length of messages to receive for ij-structure */
4898:   PetscCall(PetscGatherNumberOfMessages(comm, NULL, len_s, &merge->nrecv));
4899:   PetscCall(PetscGatherMessageLengths2(comm, merge->nsend, merge->nrecv, len_s, len_si, &merge->id_r, &merge->len_r, &len_ri));

4901:   /* post the Irecv of j-structure */
4902:   PetscCall(PetscCommGetNewTag(comm, &tagj));
4903:   PetscCall(PetscPostIrecvInt(comm, tagj, merge->nrecv, merge->id_r, merge->len_r, &buf_rj, &rj_waits));

4905:   /* post the Isend of j-structure */
4906:   PetscCall(PetscMalloc2(merge->nsend, &si_waits, merge->nsend, &sj_waits));

4908:   for (proc = 0, k = 0; proc < size; proc++) {
4909:     if (!len_s[proc]) continue;
4910:     i = owners[proc];
4911:     PetscCallMPI(MPI_Isend(aj + ai[i], len_s[proc], MPIU_INT, proc, tagj, comm, sj_waits + k));
4912:     k++;
4913:   }

4915:   /* receives and sends of j-structure are complete */
4916:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, rj_waits, status));
4917:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, sj_waits, status));

4919:   /* send and recv i-structure */
4920:   PetscCall(PetscCommGetNewTag(comm, &tagi));
4921:   PetscCall(PetscPostIrecvInt(comm, tagi, merge->nrecv, merge->id_r, len_ri, &buf_ri, &ri_waits));

4923:   PetscCall(PetscMalloc1(len + 1, &buf_s));
4924:   buf_si = buf_s; /* points to the beginning of k-th msg to be sent */
4925:   for (proc = 0, k = 0; proc < size; proc++) {
4926:     if (!len_s[proc]) continue;
4927:     /* form outgoing message for i-structure:
4928:          buf_si[0]:                 nrows to be sent
4929:                [1:nrows]:           row index (global)
4930:                [nrows+1:2*nrows+1]: i-structure index
4931:     */
4932:     nrows       = len_si[proc] / 2 - 1;
4933:     buf_si_i    = buf_si + nrows + 1;
4934:     buf_si[0]   = nrows;
4935:     buf_si_i[0] = 0;
4936:     nrows       = 0;
4937:     for (i = owners[proc]; i < owners[proc + 1]; i++) {
4938:       anzi = ai[i + 1] - ai[i];
4939:       if (anzi) {
4940:         buf_si_i[nrows + 1] = buf_si_i[nrows] + anzi; /* i-structure */
4941:         buf_si[nrows + 1]   = i - owners[proc];       /* local row index */
4942:         nrows++;
4943:       }
4944:     }
4945:     PetscCallMPI(MPI_Isend(buf_si, len_si[proc], MPIU_INT, proc, tagi, comm, si_waits + k));
4946:     k++;
4947:     buf_si += len_si[proc];
4948:   }

4950:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, ri_waits, status));
4951:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, si_waits, status));

4953:   PetscCall(PetscInfo(seqmat, "nsend: %d, nrecv: %d\n", merge->nsend, merge->nrecv));
4954:   for (i = 0; i < merge->nrecv; i++) PetscCall(PetscInfo(seqmat, "recv len_ri=%d, len_rj=%d from [%d]\n", len_ri[i], merge->len_r[i], merge->id_r[i]));

4956:   PetscCall(PetscFree(len_si));
4957:   PetscCall(PetscFree(len_ri));
4958:   PetscCall(PetscFree(rj_waits));
4959:   PetscCall(PetscFree2(si_waits, sj_waits));
4960:   PetscCall(PetscFree(ri_waits));
4961:   PetscCall(PetscFree(buf_s));
4962:   PetscCall(PetscFree(status));

4964:   /* compute a local seq matrix in each processor */
4965:   /* allocate bi array and free space for accumulating nonzero column info */
4966:   PetscCall(PetscMalloc1(m + 1, &bi));
4967:   bi[0] = 0;

4969:   /* create and initialize a linked list */
4970:   nlnk = N + 1;
4971:   PetscCall(PetscLLCreate(N, N, nlnk, lnk, lnkbt));

4973:   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4974:   len = ai[owners[rank + 1]] - ai[owners[rank]];
4975:   PetscCall(PetscFreeSpaceGet(PetscIntMultTruncate(2, len) + 1, &free_space));

4977:   current_space = free_space;

4979:   /* determine symbolic info for each local row */
4980:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4982:   for (k = 0; k < merge->nrecv; k++) {
4983:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4984:     nrows       = *buf_ri_k[k];
4985:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4986:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4987:   }

4989:   MatPreallocateBegin(comm, m, n, dnz, onz);
4990:   len = 0;
4991:   for (i = 0; i < m; i++) {
4992:     bnzi = 0;
4993:     /* add local non-zero cols of this proc's seqmat into lnk */
4994:     arow = owners[rank] + i;
4995:     anzi = ai[arow + 1] - ai[arow];
4996:     aj   = a->j + ai[arow];
4997:     PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4998:     bnzi += nlnk;
4999:     /* add received col data into lnk */
5000:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
5001:       if (i == *nextrow[k]) {            /* i-th row */
5002:         anzi = *(nextai[k] + 1) - *nextai[k];
5003:         aj   = buf_rj[k] + *nextai[k];
5004:         PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
5005:         bnzi += nlnk;
5006:         nextrow[k]++;
5007:         nextai[k]++;
5008:       }
5009:     }
5010:     if (len < bnzi) len = bnzi; /* =max(bnzi) */

5012:     /* if free space is not available, make more free space */
5013:     if (current_space->local_remaining < bnzi) PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(bnzi, current_space->total_array_size), &current_space));
5014:     /* copy data into free space, then initialize lnk */
5015:     PetscCall(PetscLLClean(N, N, bnzi, lnk, current_space->array, lnkbt));
5016:     PetscCall(MatPreallocateSet(i + owners[rank], bnzi, current_space->array, dnz, onz));

5018:     current_space->array += bnzi;
5019:     current_space->local_used += bnzi;
5020:     current_space->local_remaining -= bnzi;

5022:     bi[i + 1] = bi[i] + bnzi;
5023:   }

5025:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));

5027:   PetscCall(PetscMalloc1(bi[m] + 1, &bj));
5028:   PetscCall(PetscFreeSpaceContiguous(&free_space, bj));
5029:   PetscCall(PetscLLDestroy(lnk, lnkbt));

5031:   /* create symbolic parallel matrix B_mpi */
5032:   PetscCall(MatGetBlockSizes(seqmat, &bs, &cbs));
5033:   PetscCall(MatCreate(comm, &B_mpi));
5034:   if (n == PETSC_DECIDE) {
5035:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, N));
5036:   } else {
5037:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
5038:   }
5039:   PetscCall(MatSetBlockSizes(B_mpi, bs, cbs));
5040:   PetscCall(MatSetType(B_mpi, MATMPIAIJ));
5041:   PetscCall(MatMPIAIJSetPreallocation(B_mpi, 0, dnz, 0, onz));
5042:   MatPreallocateEnd(dnz, onz);
5043:   PetscCall(MatSetOption(B_mpi, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));

5045:   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
5046:   B_mpi->assembled = PETSC_FALSE;
5047:   merge->bi        = bi;
5048:   merge->bj        = bj;
5049:   merge->buf_ri    = buf_ri;
5050:   merge->buf_rj    = buf_rj;
5051:   merge->coi       = NULL;
5052:   merge->coj       = NULL;
5053:   merge->owners_co = NULL;

5055:   PetscCall(PetscCommDestroy(&comm));

5057:   /* attach the supporting struct to B_mpi for reuse */
5058:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
5059:   PetscCall(PetscContainerSetPointer(container, merge));
5060:   PetscCall(PetscContainerSetUserDestroy(container, MatDestroy_MPIAIJ_SeqsToMPI));
5061:   PetscCall(PetscObjectCompose((PetscObject)B_mpi, "MatMergeSeqsToMPI", (PetscObject)container));
5062:   PetscCall(PetscContainerDestroy(&container));
5063:   *mpimat = B_mpi;

5065:   PetscCall(PetscLogEventEnd(MAT_Seqstompisym, seqmat, 0, 0, 0));
5066:   PetscFunctionReturn(PETSC_SUCCESS);
5067: }

5069: /*@C
5070:   MatCreateMPIAIJSumSeqAIJ - Creates a `MATMPIAIJ` matrix by adding sequential
5071:   matrices from each processor

5073:   Collective

5075:   Input Parameters:
5076: + comm   - the communicators the parallel matrix will live on
5077: . seqmat - the input sequential matrices
5078: . m      - number of local rows (or `PETSC_DECIDE`)
5079: . n      - number of local columns (or `PETSC_DECIDE`)
5080: - scall  - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5082:   Output Parameter:
5083: . mpimat - the parallel matrix generated

5085:   Level: advanced

5087:   Note:
5088:   The dimensions of the sequential matrix in each processor MUST be the same.
5089:   The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
5090:   destroyed when `mpimat` is destroyed. Call `PetscObjectQuery()` to access `seqmat`.

5092: .seealso: [](ch_matrices), `Mat`, `MatCreateAIJ()`
5093: @*/
5094: PetscErrorCode MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, MatReuse scall, Mat *mpimat)
5095: {
5096:   PetscMPIInt size;

5098:   PetscFunctionBegin;
5099:   PetscCallMPI(MPI_Comm_size(comm, &size));
5100:   if (size == 1) {
5101:     PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5102:     if (scall == MAT_INITIAL_MATRIX) {
5103:       PetscCall(MatDuplicate(seqmat, MAT_COPY_VALUES, mpimat));
5104:     } else {
5105:       PetscCall(MatCopy(seqmat, *mpimat, SAME_NONZERO_PATTERN));
5106:     }
5107:     PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5108:     PetscFunctionReturn(PETSC_SUCCESS);
5109:   }
5110:   PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5111:   if (scall == MAT_INITIAL_MATRIX) PetscCall(MatCreateMPIAIJSumSeqAIJSymbolic(comm, seqmat, m, n, mpimat));
5112:   PetscCall(MatCreateMPIAIJSumSeqAIJNumeric(seqmat, *mpimat));
5113:   PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5114:   PetscFunctionReturn(PETSC_SUCCESS);
5115: }

5117: /*@
5118:   MatAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATAIJ` matrix.

5120:   Not Collective

5122:   Input Parameter:
5123: . A - the matrix

5125:   Output Parameter:
5126: . A_loc - the local sequential matrix generated

5128:   Level: developer

5130:   Notes:
5131:   The matrix is created by taking `A`'s local rows and putting them into a sequential matrix
5132:   with `mlocal` rows and `n` columns. Where `mlocal` is obtained with `MatGetLocalSize()` and
5133:   `n` is the global column count obtained with `MatGetSize()`

5135:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5137:   For parallel matrices this creates an entirely new matrix. If the matrix is sequential it merely increases the reference count.

5139:   Destroy the matrix with `MatDestroy()`

5141: .seealso: [](ch_matrices), `Mat`, `MatMPIAIJGetLocalMat()`
5142: @*/
5143: PetscErrorCode MatAIJGetLocalMat(Mat A, Mat *A_loc)
5144: {
5145:   PetscBool mpi;

5147:   PetscFunctionBegin;
5148:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &mpi));
5149:   if (mpi) {
5150:     PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, A_loc));
5151:   } else {
5152:     *A_loc = A;
5153:     PetscCall(PetscObjectReference((PetscObject)*A_loc));
5154:   }
5155:   PetscFunctionReturn(PETSC_SUCCESS);
5156: }

5158: /*@
5159:   MatMPIAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix.

5161:   Not Collective

5163:   Input Parameters:
5164: + A     - the matrix
5165: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5167:   Output Parameter:
5168: . A_loc - the local sequential matrix generated

5170:   Level: developer

5172:   Notes:
5173:   The matrix is created by taking all `A`'s local rows and putting them into a sequential
5174:   matrix with `mlocal` rows and `n` columns.`mlocal` is the row count obtained with
5175:   `MatGetLocalSize()` and `n` is the global column count obtained with `MatGetSize()`.

5177:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5179:   When `A` is sequential and `MAT_INITIAL_MATRIX` is requested, the matrix returned is the diagonal part of `A` (which contains the entire matrix),
5180:   with its reference count increased by one. Hence changing values of `A_loc` changes `A`. If `MAT_REUSE_MATRIX` is requested on a sequential matrix
5181:   then `MatCopy`(Adiag,*`A_loc`,`SAME_NONZERO_PATTERN`) is called to fill `A_loc`. Thus one can preallocate the appropriate sequential matrix `A_loc`
5182:   and then call this routine with `MAT_REUSE_MATRIX`. In this case, one can modify the values of `A_loc` without affecting the original sequential matrix.

5184: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMatCondensed()`, `MatMPIAIJGetLocalMatMerge()`
5185: @*/
5186: PetscErrorCode MatMPIAIJGetLocalMat(Mat A, MatReuse scall, Mat *A_loc)
5187: {
5188:   Mat_MPIAIJ        *mpimat = (Mat_MPIAIJ *)A->data;
5189:   Mat_SeqAIJ        *mat, *a, *b;
5190:   PetscInt          *ai, *aj, *bi, *bj, *cmap = mpimat->garray;
5191:   const PetscScalar *aa, *ba, *aav, *bav;
5192:   PetscScalar       *ca, *cam;
5193:   PetscMPIInt        size;
5194:   PetscInt           am = A->rmap->n, i, j, k, cstart = A->cmap->rstart;
5195:   PetscInt          *ci, *cj, col, ncols_d, ncols_o, jo;
5196:   PetscBool          match;

5198:   PetscFunctionBegin;
5199:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &match));
5200:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5201:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5202:   if (size == 1) {
5203:     if (scall == MAT_INITIAL_MATRIX) {
5204:       PetscCall(PetscObjectReference((PetscObject)mpimat->A));
5205:       *A_loc = mpimat->A;
5206:     } else if (scall == MAT_REUSE_MATRIX) {
5207:       PetscCall(MatCopy(mpimat->A, *A_loc, SAME_NONZERO_PATTERN));
5208:     }
5209:     PetscFunctionReturn(PETSC_SUCCESS);
5210:   }

5212:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5213:   a  = (Mat_SeqAIJ *)mpimat->A->data;
5214:   b  = (Mat_SeqAIJ *)mpimat->B->data;
5215:   ai = a->i;
5216:   aj = a->j;
5217:   bi = b->i;
5218:   bj = b->j;
5219:   PetscCall(MatSeqAIJGetArrayRead(mpimat->A, &aav));
5220:   PetscCall(MatSeqAIJGetArrayRead(mpimat->B, &bav));
5221:   aa = aav;
5222:   ba = bav;
5223:   if (scall == MAT_INITIAL_MATRIX) {
5224:     PetscCall(PetscMalloc1(1 + am, &ci));
5225:     ci[0] = 0;
5226:     for (i = 0; i < am; i++) ci[i + 1] = ci[i] + (ai[i + 1] - ai[i]) + (bi[i + 1] - bi[i]);
5227:     PetscCall(PetscMalloc1(1 + ci[am], &cj));
5228:     PetscCall(PetscMalloc1(1 + ci[am], &ca));
5229:     k = 0;
5230:     for (i = 0; i < am; i++) {
5231:       ncols_o = bi[i + 1] - bi[i];
5232:       ncols_d = ai[i + 1] - ai[i];
5233:       /* off-diagonal portion of A */
5234:       for (jo = 0; jo < ncols_o; jo++) {
5235:         col = cmap[*bj];
5236:         if (col >= cstart) break;
5237:         cj[k] = col;
5238:         bj++;
5239:         ca[k++] = *ba++;
5240:       }
5241:       /* diagonal portion of A */
5242:       for (j = 0; j < ncols_d; j++) {
5243:         cj[k]   = cstart + *aj++;
5244:         ca[k++] = *aa++;
5245:       }
5246:       /* off-diagonal portion of A */
5247:       for (j = jo; j < ncols_o; j++) {
5248:         cj[k]   = cmap[*bj++];
5249:         ca[k++] = *ba++;
5250:       }
5251:     }
5252:     /* put together the new matrix */
5253:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, A->cmap->N, ci, cj, ca, A_loc));
5254:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5255:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5256:     mat          = (Mat_SeqAIJ *)(*A_loc)->data;
5257:     mat->free_a  = PETSC_TRUE;
5258:     mat->free_ij = PETSC_TRUE;
5259:     mat->nonew   = 0;
5260:   } else if (scall == MAT_REUSE_MATRIX) {
5261:     mat = (Mat_SeqAIJ *)(*A_loc)->data;
5262:     ci  = mat->i;
5263:     cj  = mat->j;
5264:     PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &cam));
5265:     for (i = 0; i < am; i++) {
5266:       /* off-diagonal portion of A */
5267:       ncols_o = bi[i + 1] - bi[i];
5268:       for (jo = 0; jo < ncols_o; jo++) {
5269:         col = cmap[*bj];
5270:         if (col >= cstart) break;
5271:         *cam++ = *ba++;
5272:         bj++;
5273:       }
5274:       /* diagonal portion of A */
5275:       ncols_d = ai[i + 1] - ai[i];
5276:       for (j = 0; j < ncols_d; j++) *cam++ = *aa++;
5277:       /* off-diagonal portion of A */
5278:       for (j = jo; j < ncols_o; j++) {
5279:         *cam++ = *ba++;
5280:         bj++;
5281:       }
5282:     }
5283:     PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &cam));
5284:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5285:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->A, &aav));
5286:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->B, &bav));
5287:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5288:   PetscFunctionReturn(PETSC_SUCCESS);
5289: }

5291: /*@
5292:   MatMPIAIJGetLocalMatMerge - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix by taking all its local rows and putting them into a sequential matrix with
5293:   mlocal rows and n columns. Where n is the sum of the number of columns of the diagonal and off-diagonal part

5295:   Not Collective

5297:   Input Parameters:
5298: + A     - the matrix
5299: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5301:   Output Parameters:
5302: + glob  - sequential `IS` with global indices associated with the columns of the local sequential matrix generated (can be `NULL`)
5303: - A_loc - the local sequential matrix generated

5305:   Level: developer

5307:   Note:
5308:   This is different from `MatMPIAIJGetLocalMat()` since the first columns in the returning matrix are those associated with the diagonal
5309:   part, then those associated with the off-diagonal part (in its local ordering)

5311: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`
5312: @*/
5313: PetscErrorCode MatMPIAIJGetLocalMatMerge(Mat A, MatReuse scall, IS *glob, Mat *A_loc)
5314: {
5315:   Mat             Ao, Ad;
5316:   const PetscInt *cmap;
5317:   PetscMPIInt     size;
5318:   PetscErrorCode (*f)(Mat, MatReuse, IS *, Mat *);

5320:   PetscFunctionBegin;
5321:   PetscCall(MatMPIAIJGetSeqAIJ(A, &Ad, &Ao, &cmap));
5322:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5323:   if (size == 1) {
5324:     if (scall == MAT_INITIAL_MATRIX) {
5325:       PetscCall(PetscObjectReference((PetscObject)Ad));
5326:       *A_loc = Ad;
5327:     } else if (scall == MAT_REUSE_MATRIX) {
5328:       PetscCall(MatCopy(Ad, *A_loc, SAME_NONZERO_PATTERN));
5329:     }
5330:     if (glob) PetscCall(ISCreateStride(PetscObjectComm((PetscObject)Ad), Ad->cmap->n, Ad->cmap->rstart, 1, glob));
5331:     PetscFunctionReturn(PETSC_SUCCESS);
5332:   }
5333:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatMPIAIJGetLocalMatMerge_C", &f));
5334:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5335:   if (f) {
5336:     PetscCall((*f)(A, scall, glob, A_loc));
5337:   } else {
5338:     Mat_SeqAIJ        *a = (Mat_SeqAIJ *)Ad->data;
5339:     Mat_SeqAIJ        *b = (Mat_SeqAIJ *)Ao->data;
5340:     Mat_SeqAIJ        *c;
5341:     PetscInt          *ai = a->i, *aj = a->j;
5342:     PetscInt          *bi = b->i, *bj = b->j;
5343:     PetscInt          *ci, *cj;
5344:     const PetscScalar *aa, *ba;
5345:     PetscScalar       *ca;
5346:     PetscInt           i, j, am, dn, on;

5348:     PetscCall(MatGetLocalSize(Ad, &am, &dn));
5349:     PetscCall(MatGetLocalSize(Ao, NULL, &on));
5350:     PetscCall(MatSeqAIJGetArrayRead(Ad, &aa));
5351:     PetscCall(MatSeqAIJGetArrayRead(Ao, &ba));
5352:     if (scall == MAT_INITIAL_MATRIX) {
5353:       PetscInt k;
5354:       PetscCall(PetscMalloc1(1 + am, &ci));
5355:       PetscCall(PetscMalloc1(ai[am] + bi[am], &cj));
5356:       PetscCall(PetscMalloc1(ai[am] + bi[am], &ca));
5357:       ci[0] = 0;
5358:       for (i = 0, k = 0; i < am; i++) {
5359:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5360:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5361:         ci[i + 1]              = ci[i] + ncols_o + ncols_d;
5362:         /* diagonal portion of A */
5363:         for (j = 0; j < ncols_d; j++, k++) {
5364:           cj[k] = *aj++;
5365:           ca[k] = *aa++;
5366:         }
5367:         /* off-diagonal portion of A */
5368:         for (j = 0; j < ncols_o; j++, k++) {
5369:           cj[k] = dn + *bj++;
5370:           ca[k] = *ba++;
5371:         }
5372:       }
5373:       /* put together the new matrix */
5374:       PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, dn + on, ci, cj, ca, A_loc));
5375:       /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5376:       /* Since these are PETSc arrays, change flags to free them as necessary. */
5377:       c          = (Mat_SeqAIJ *)(*A_loc)->data;
5378:       c->free_a  = PETSC_TRUE;
5379:       c->free_ij = PETSC_TRUE;
5380:       c->nonew   = 0;
5381:       PetscCall(MatSetType(*A_loc, ((PetscObject)Ad)->type_name));
5382:     } else if (scall == MAT_REUSE_MATRIX) {
5383:       PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &ca));
5384:       for (i = 0; i < am; i++) {
5385:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5386:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5387:         /* diagonal portion of A */
5388:         for (j = 0; j < ncols_d; j++) *ca++ = *aa++;
5389:         /* off-diagonal portion of A */
5390:         for (j = 0; j < ncols_o; j++) *ca++ = *ba++;
5391:       }
5392:       PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &ca));
5393:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5394:     PetscCall(MatSeqAIJRestoreArrayRead(Ad, &aa));
5395:     PetscCall(MatSeqAIJRestoreArrayRead(Ao, &aa));
5396:     if (glob) {
5397:       PetscInt cst, *gidx;

5399:       PetscCall(MatGetOwnershipRangeColumn(A, &cst, NULL));
5400:       PetscCall(PetscMalloc1(dn + on, &gidx));
5401:       for (i = 0; i < dn; i++) gidx[i] = cst + i;
5402:       for (i = 0; i < on; i++) gidx[i + dn] = cmap[i];
5403:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)Ad), dn + on, gidx, PETSC_OWN_POINTER, glob));
5404:     }
5405:   }
5406:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5407:   PetscFunctionReturn(PETSC_SUCCESS);
5408: }

5410: /*@C
5411:   MatMPIAIJGetLocalMatCondensed - Creates a `MATSEQAIJ` matrix from an `MATMPIAIJ` matrix by taking all its local rows and NON-ZERO columns

5413:   Not Collective

5415:   Input Parameters:
5416: + A     - the matrix
5417: . scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`
5418: . row   - index set of rows to extract (or `NULL`)
5419: - col   - index set of columns to extract (or `NULL`)

5421:   Output Parameter:
5422: . A_loc - the local sequential matrix generated

5424:   Level: developer

5426: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`
5427: @*/
5428: PetscErrorCode MatMPIAIJGetLocalMatCondensed(Mat A, MatReuse scall, IS *row, IS *col, Mat *A_loc)
5429: {
5430:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5431:   PetscInt    i, start, end, ncols, nzA, nzB, *cmap, imark, *idx;
5432:   IS          isrowa, iscola;
5433:   Mat        *aloc;
5434:   PetscBool   match;

5436:   PetscFunctionBegin;
5437:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &match));
5438:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5439:   PetscCall(PetscLogEventBegin(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5440:   if (!row) {
5441:     start = A->rmap->rstart;
5442:     end   = A->rmap->rend;
5443:     PetscCall(ISCreateStride(PETSC_COMM_SELF, end - start, start, 1, &isrowa));
5444:   } else {
5445:     isrowa = *row;
5446:   }
5447:   if (!col) {
5448:     start = A->cmap->rstart;
5449:     cmap  = a->garray;
5450:     nzA   = a->A->cmap->n;
5451:     nzB   = a->B->cmap->n;
5452:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5453:     ncols = 0;
5454:     for (i = 0; i < nzB; i++) {
5455:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5456:       else break;
5457:     }
5458:     imark = i;
5459:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;
5460:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i];
5461:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &iscola));
5462:   } else {
5463:     iscola = *col;
5464:   }
5465:   if (scall != MAT_INITIAL_MATRIX) {
5466:     PetscCall(PetscMalloc1(1, &aloc));
5467:     aloc[0] = *A_loc;
5468:   }
5469:   PetscCall(MatCreateSubMatrices(A, 1, &isrowa, &iscola, scall, &aloc));
5470:   if (!col) { /* attach global id of condensed columns */
5471:     PetscCall(PetscObjectCompose((PetscObject)aloc[0], "_petsc_GetLocalMatCondensed_iscol", (PetscObject)iscola));
5472:   }
5473:   *A_loc = aloc[0];
5474:   PetscCall(PetscFree(aloc));
5475:   if (!row) PetscCall(ISDestroy(&isrowa));
5476:   if (!col) PetscCall(ISDestroy(&iscola));
5477:   PetscCall(PetscLogEventEnd(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5478:   PetscFunctionReturn(PETSC_SUCCESS);
5479: }

5481: /*
5482:  * Create a sequential AIJ matrix based on row indices. a whole column is extracted once a row is matched.
5483:  * Row could be local or remote.The routine is designed to be scalable in memory so that nothing is based
5484:  * on a global size.
5485:  * */
5486: static PetscErrorCode MatCreateSeqSubMatrixWithRows_Private(Mat P, IS rows, Mat *P_oth)
5487: {
5488:   Mat_MPIAIJ            *p  = (Mat_MPIAIJ *)P->data;
5489:   Mat_SeqAIJ            *pd = (Mat_SeqAIJ *)p->A->data, *po = (Mat_SeqAIJ *)p->B->data, *p_oth;
5490:   PetscInt               plocalsize, nrows, *ilocal, *oilocal, i, lidx, *nrcols, *nlcols, ncol;
5491:   PetscMPIInt            owner;
5492:   PetscSFNode           *iremote, *oiremote;
5493:   const PetscInt        *lrowindices;
5494:   PetscSF                sf, osf;
5495:   PetscInt               pcstart, *roffsets, *loffsets, *pnnz, j;
5496:   PetscInt               ontotalcols, dntotalcols, ntotalcols, nout;
5497:   MPI_Comm               comm;
5498:   ISLocalToGlobalMapping mapping;
5499:   const PetscScalar     *pd_a, *po_a;

5501:   PetscFunctionBegin;
5502:   PetscCall(PetscObjectGetComm((PetscObject)P, &comm));
5503:   /* plocalsize is the number of roots
5504:    * nrows is the number of leaves
5505:    * */
5506:   PetscCall(MatGetLocalSize(P, &plocalsize, NULL));
5507:   PetscCall(ISGetLocalSize(rows, &nrows));
5508:   PetscCall(PetscCalloc1(nrows, &iremote));
5509:   PetscCall(ISGetIndices(rows, &lrowindices));
5510:   for (i = 0; i < nrows; i++) {
5511:     /* Find a remote index and an owner for a row
5512:      * The row could be local or remote
5513:      * */
5514:     owner = 0;
5515:     lidx  = 0;
5516:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, &lidx));
5517:     iremote[i].index = lidx;
5518:     iremote[i].rank  = owner;
5519:   }
5520:   /* Create SF to communicate how many nonzero columns for each row */
5521:   PetscCall(PetscSFCreate(comm, &sf));
5522:   /* SF will figure out the number of nonzero columns for each row, and their
5523:    * offsets
5524:    * */
5525:   PetscCall(PetscSFSetGraph(sf, plocalsize, nrows, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5526:   PetscCall(PetscSFSetFromOptions(sf));
5527:   PetscCall(PetscSFSetUp(sf));

5529:   PetscCall(PetscCalloc1(2 * (plocalsize + 1), &roffsets));
5530:   PetscCall(PetscCalloc1(2 * plocalsize, &nrcols));
5531:   PetscCall(PetscCalloc1(nrows, &pnnz));
5532:   roffsets[0] = 0;
5533:   roffsets[1] = 0;
5534:   for (i = 0; i < plocalsize; i++) {
5535:     /* diagonal */
5536:     nrcols[i * 2 + 0] = pd->i[i + 1] - pd->i[i];
5537:     /* off-diagonal */
5538:     nrcols[i * 2 + 1] = po->i[i + 1] - po->i[i];
5539:     /* compute offsets so that we relative location for each row */
5540:     roffsets[(i + 1) * 2 + 0] = roffsets[i * 2 + 0] + nrcols[i * 2 + 0];
5541:     roffsets[(i + 1) * 2 + 1] = roffsets[i * 2 + 1] + nrcols[i * 2 + 1];
5542:   }
5543:   PetscCall(PetscCalloc1(2 * nrows, &nlcols));
5544:   PetscCall(PetscCalloc1(2 * nrows, &loffsets));
5545:   /* 'r' means root, and 'l' means leaf */
5546:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5547:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5548:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5549:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5550:   PetscCall(PetscSFDestroy(&sf));
5551:   PetscCall(PetscFree(roffsets));
5552:   PetscCall(PetscFree(nrcols));
5553:   dntotalcols = 0;
5554:   ontotalcols = 0;
5555:   ncol        = 0;
5556:   for (i = 0; i < nrows; i++) {
5557:     pnnz[i] = nlcols[i * 2 + 0] + nlcols[i * 2 + 1];
5558:     ncol    = PetscMax(pnnz[i], ncol);
5559:     /* diagonal */
5560:     dntotalcols += nlcols[i * 2 + 0];
5561:     /* off-diagonal */
5562:     ontotalcols += nlcols[i * 2 + 1];
5563:   }
5564:   /* We do not need to figure the right number of columns
5565:    * since all the calculations will be done by going through the raw data
5566:    * */
5567:   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nrows, ncol, 0, pnnz, P_oth));
5568:   PetscCall(MatSetUp(*P_oth));
5569:   PetscCall(PetscFree(pnnz));
5570:   p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5571:   /* diagonal */
5572:   PetscCall(PetscCalloc1(dntotalcols, &iremote));
5573:   /* off-diagonal */
5574:   PetscCall(PetscCalloc1(ontotalcols, &oiremote));
5575:   /* diagonal */
5576:   PetscCall(PetscCalloc1(dntotalcols, &ilocal));
5577:   /* off-diagonal */
5578:   PetscCall(PetscCalloc1(ontotalcols, &oilocal));
5579:   dntotalcols = 0;
5580:   ontotalcols = 0;
5581:   ntotalcols  = 0;
5582:   for (i = 0; i < nrows; i++) {
5583:     owner = 0;
5584:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, NULL));
5585:     /* Set iremote for diag matrix */
5586:     for (j = 0; j < nlcols[i * 2 + 0]; j++) {
5587:       iremote[dntotalcols].index = loffsets[i * 2 + 0] + j;
5588:       iremote[dntotalcols].rank  = owner;
5589:       /* P_oth is seqAIJ so that ilocal need to point to the first part of memory */
5590:       ilocal[dntotalcols++] = ntotalcols++;
5591:     }
5592:     /* off-diagonal */
5593:     for (j = 0; j < nlcols[i * 2 + 1]; j++) {
5594:       oiremote[ontotalcols].index = loffsets[i * 2 + 1] + j;
5595:       oiremote[ontotalcols].rank  = owner;
5596:       oilocal[ontotalcols++]      = ntotalcols++;
5597:     }
5598:   }
5599:   PetscCall(ISRestoreIndices(rows, &lrowindices));
5600:   PetscCall(PetscFree(loffsets));
5601:   PetscCall(PetscFree(nlcols));
5602:   PetscCall(PetscSFCreate(comm, &sf));
5603:   /* P serves as roots and P_oth is leaves
5604:    * Diag matrix
5605:    * */
5606:   PetscCall(PetscSFSetGraph(sf, pd->i[plocalsize], dntotalcols, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5607:   PetscCall(PetscSFSetFromOptions(sf));
5608:   PetscCall(PetscSFSetUp(sf));

5610:   PetscCall(PetscSFCreate(comm, &osf));
5611:   /* off-diagonal */
5612:   PetscCall(PetscSFSetGraph(osf, po->i[plocalsize], ontotalcols, oilocal, PETSC_OWN_POINTER, oiremote, PETSC_OWN_POINTER));
5613:   PetscCall(PetscSFSetFromOptions(osf));
5614:   PetscCall(PetscSFSetUp(osf));
5615:   PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5616:   PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5617:   /* operate on the matrix internal data to save memory */
5618:   PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5619:   PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5620:   PetscCall(MatGetOwnershipRangeColumn(P, &pcstart, NULL));
5621:   /* Convert to global indices for diag matrix */
5622:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] += pcstart;
5623:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5624:   /* We want P_oth store global indices */
5625:   PetscCall(ISLocalToGlobalMappingCreate(comm, 1, p->B->cmap->n, p->garray, PETSC_COPY_VALUES, &mapping));
5626:   /* Use memory scalable approach */
5627:   PetscCall(ISLocalToGlobalMappingSetType(mapping, ISLOCALTOGLOBALMAPPINGHASH));
5628:   PetscCall(ISLocalToGlobalMappingApply(mapping, po->i[plocalsize], po->j, po->j));
5629:   PetscCall(PetscSFBcastBegin(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5630:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5631:   /* Convert back to local indices */
5632:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] -= pcstart;
5633:   PetscCall(PetscSFBcastEnd(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5634:   nout = 0;
5635:   PetscCall(ISGlobalToLocalMappingApply(mapping, IS_GTOLM_DROP, po->i[plocalsize], po->j, &nout, po->j));
5636:   PetscCheck(nout == po->i[plocalsize], comm, PETSC_ERR_ARG_INCOMP, "n %" PetscInt_FMT " does not equal to nout %" PetscInt_FMT " ", po->i[plocalsize], nout);
5637:   PetscCall(ISLocalToGlobalMappingDestroy(&mapping));
5638:   /* Exchange values */
5639:   PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5640:   PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5641:   PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5642:   PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5643:   /* Stop PETSc from shrinking memory */
5644:   for (i = 0; i < nrows; i++) p_oth->ilen[i] = p_oth->imax[i];
5645:   PetscCall(MatAssemblyBegin(*P_oth, MAT_FINAL_ASSEMBLY));
5646:   PetscCall(MatAssemblyEnd(*P_oth, MAT_FINAL_ASSEMBLY));
5647:   /* Attach PetscSF objects to P_oth so that we can reuse it later */
5648:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "diagsf", (PetscObject)sf));
5649:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "offdiagsf", (PetscObject)osf));
5650:   PetscCall(PetscSFDestroy(&sf));
5651:   PetscCall(PetscSFDestroy(&osf));
5652:   PetscFunctionReturn(PETSC_SUCCESS);
5653: }

5655: /*
5656:  * Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5657:  * This supports MPIAIJ and MAIJ
5658:  * */
5659: PetscErrorCode MatGetBrowsOfAcols_MPIXAIJ(Mat A, Mat P, PetscInt dof, MatReuse reuse, Mat *P_oth)
5660: {
5661:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data, *p = (Mat_MPIAIJ *)P->data;
5662:   Mat_SeqAIJ *p_oth;
5663:   IS          rows, map;
5664:   PetscHMapI  hamp;
5665:   PetscInt    i, htsize, *rowindices, off, *mapping, key, count;
5666:   MPI_Comm    comm;
5667:   PetscSF     sf, osf;
5668:   PetscBool   has;

5670:   PetscFunctionBegin;
5671:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5672:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, P, 0, 0));
5673:   /* If it is the first time, create an index set of off-diag nonzero columns of A,
5674:    *  and then create a submatrix (that often is an overlapping matrix)
5675:    * */
5676:   if (reuse == MAT_INITIAL_MATRIX) {
5677:     /* Use a hash table to figure out unique keys */
5678:     PetscCall(PetscHMapICreateWithSize(a->B->cmap->n, &hamp));
5679:     PetscCall(PetscCalloc1(a->B->cmap->n, &mapping));
5680:     count = 0;
5681:     /* Assume that  a->g is sorted, otherwise the following does not make sense */
5682:     for (i = 0; i < a->B->cmap->n; i++) {
5683:       key = a->garray[i] / dof;
5684:       PetscCall(PetscHMapIHas(hamp, key, &has));
5685:       if (!has) {
5686:         mapping[i] = count;
5687:         PetscCall(PetscHMapISet(hamp, key, count++));
5688:       } else {
5689:         /* Current 'i' has the same value the previous step */
5690:         mapping[i] = count - 1;
5691:       }
5692:     }
5693:     PetscCall(ISCreateGeneral(comm, a->B->cmap->n, mapping, PETSC_OWN_POINTER, &map));
5694:     PetscCall(PetscHMapIGetSize(hamp, &htsize));
5695:     PetscCheck(htsize == count, comm, PETSC_ERR_ARG_INCOMP, " Size of hash map %" PetscInt_FMT " is inconsistent with count %" PetscInt_FMT, htsize, count);
5696:     PetscCall(PetscCalloc1(htsize, &rowindices));
5697:     off = 0;
5698:     PetscCall(PetscHMapIGetKeys(hamp, &off, rowindices));
5699:     PetscCall(PetscHMapIDestroy(&hamp));
5700:     PetscCall(PetscSortInt(htsize, rowindices));
5701:     PetscCall(ISCreateGeneral(comm, htsize, rowindices, PETSC_OWN_POINTER, &rows));
5702:     /* In case, the matrix was already created but users want to recreate the matrix */
5703:     PetscCall(MatDestroy(P_oth));
5704:     PetscCall(MatCreateSeqSubMatrixWithRows_Private(P, rows, P_oth));
5705:     PetscCall(PetscObjectCompose((PetscObject)*P_oth, "aoffdiagtopothmapping", (PetscObject)map));
5706:     PetscCall(ISDestroy(&map));
5707:     PetscCall(ISDestroy(&rows));
5708:   } else if (reuse == MAT_REUSE_MATRIX) {
5709:     /* If matrix was already created, we simply update values using SF objects
5710:      * that as attached to the matrix earlier.
5711:      */
5712:     const PetscScalar *pd_a, *po_a;

5714:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "diagsf", (PetscObject *)&sf));
5715:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "offdiagsf", (PetscObject *)&osf));
5716:     PetscCheck(sf && osf, comm, PETSC_ERR_ARG_NULL, "Matrix is not initialized yet");
5717:     p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5718:     /* Update values in place */
5719:     PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5720:     PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5721:     PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5722:     PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5723:     PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5724:     PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5725:     PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5726:     PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5727:   } else SETERRQ(comm, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown reuse type");
5728:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, P, 0, 0));
5729:   PetscFunctionReturn(PETSC_SUCCESS);
5730: }

5732: /*@C
5733:   MatGetBrowsOfAcols - Returns `IS` that contain rows of `B` that equal to nonzero columns of local `A`

5735:   Collective

5737:   Input Parameters:
5738: + A     - the first matrix in `MATMPIAIJ` format
5739: . B     - the second matrix in `MATMPIAIJ` format
5740: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5742:   Output Parameters:
5743: + rowb  - On input index sets of rows of B to extract (or `NULL`), modified on output
5744: . colb  - On input index sets of columns of B to extract (or `NULL`), modified on output
5745: - B_seq - the sequential matrix generated

5747:   Level: developer

5749: .seealso: `Mat`, `MATMPIAIJ`, `IS`, `MatReuse`
5750: @*/
5751: PetscErrorCode MatGetBrowsOfAcols(Mat A, Mat B, MatReuse scall, IS *rowb, IS *colb, Mat *B_seq)
5752: {
5753:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5754:   PetscInt   *idx, i, start, ncols, nzA, nzB, *cmap, imark;
5755:   IS          isrowb, iscolb;
5756:   Mat        *bseq = NULL;

5758:   PetscFunctionBegin;
5759:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
5760:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5761:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAcols, A, B, 0, 0));

5763:   if (scall == MAT_INITIAL_MATRIX) {
5764:     start = A->cmap->rstart;
5765:     cmap  = a->garray;
5766:     nzA   = a->A->cmap->n;
5767:     nzB   = a->B->cmap->n;
5768:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5769:     ncols = 0;
5770:     for (i = 0; i < nzB; i++) { /* row < local row index */
5771:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5772:       else break;
5773:     }
5774:     imark = i;
5775:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;   /* local rows */
5776:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5777:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &isrowb));
5778:     PetscCall(ISCreateStride(PETSC_COMM_SELF, B->cmap->N, 0, 1, &iscolb));
5779:   } else {
5780:     PetscCheck(rowb && colb, PETSC_COMM_SELF, PETSC_ERR_SUP, "IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5781:     isrowb = *rowb;
5782:     iscolb = *colb;
5783:     PetscCall(PetscMalloc1(1, &bseq));
5784:     bseq[0] = *B_seq;
5785:   }
5786:   PetscCall(MatCreateSubMatrices(B, 1, &isrowb, &iscolb, scall, &bseq));
5787:   *B_seq = bseq[0];
5788:   PetscCall(PetscFree(bseq));
5789:   if (!rowb) {
5790:     PetscCall(ISDestroy(&isrowb));
5791:   } else {
5792:     *rowb = isrowb;
5793:   }
5794:   if (!colb) {
5795:     PetscCall(ISDestroy(&iscolb));
5796:   } else {
5797:     *colb = iscolb;
5798:   }
5799:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAcols, A, B, 0, 0));
5800:   PetscFunctionReturn(PETSC_SUCCESS);
5801: }

5803: /*
5804:     MatGetBrowsOfAoCols_MPIAIJ - Creates a `MATSEQAIJ` matrix by taking rows of B that equal to nonzero columns
5805:     of the OFF-DIAGONAL portion of local A

5807:     Collective

5809:    Input Parameters:
5810: +    A,B - the matrices in `MATMPIAIJ` format
5811: -    scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5813:    Output Parameter:
5814: +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5815: .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5816: .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
5817: -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N

5819:     Developer Note:
5820:     This directly accesses information inside the VecScatter associated with the matrix-vector product
5821:      for this matrix. This is not desirable..

5823:     Level: developer

5825: */
5826: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ(Mat A, Mat B, MatReuse scall, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5827: {
5828:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
5829:   Mat_SeqAIJ        *b_oth;
5830:   VecScatter         ctx;
5831:   MPI_Comm           comm;
5832:   const PetscMPIInt *rprocs, *sprocs;
5833:   const PetscInt    *srow, *rstarts, *sstarts;
5834:   PetscInt          *rowlen, *bufj, *bufJ, ncols = 0, aBn = a->B->cmap->n, row, *b_othi, *b_othj, *rvalues = NULL, *svalues = NULL, *cols, sbs, rbs;
5835:   PetscInt           i, j, k = 0, l, ll, nrecvs, nsends, nrows, *rstartsj = NULL, *sstartsj, len;
5836:   PetscScalar       *b_otha, *bufa, *bufA, *vals = NULL;
5837:   MPI_Request       *reqs = NULL, *rwaits = NULL, *swaits = NULL;
5838:   PetscMPIInt        size, tag, rank, nreqs;

5840:   PetscFunctionBegin;
5841:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5842:   PetscCallMPI(MPI_Comm_size(comm, &size));

5844:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
5845:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5846:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, B, 0, 0));
5847:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

5849:   if (size == 1) {
5850:     startsj_s = NULL;
5851:     bufa_ptr  = NULL;
5852:     *B_oth    = NULL;
5853:     PetscFunctionReturn(PETSC_SUCCESS);
5854:   }

5856:   ctx = a->Mvctx;
5857:   tag = ((PetscObject)ctx)->tag;

5859:   PetscCall(VecScatterGetRemote_Private(ctx, PETSC_TRUE /*send*/, &nsends, &sstarts, &srow, &sprocs, &sbs));
5860:   /* rprocs[] must be ordered so that indices received from them are ordered in rvalues[], which is key to algorithms used in this subroutine */
5861:   PetscCall(VecScatterGetRemoteOrdered_Private(ctx, PETSC_FALSE /*recv*/, &nrecvs, &rstarts, NULL /*indices not needed*/, &rprocs, &rbs));
5862:   PetscCall(PetscMPIIntCast(nsends + nrecvs, &nreqs));
5863:   PetscCall(PetscMalloc1(nreqs, &reqs));
5864:   rwaits = reqs;
5865:   swaits = PetscSafePointerPlusOffset(reqs, nrecvs);

5867:   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5868:   if (scall == MAT_INITIAL_MATRIX) {
5869:     /* i-array */
5870:     /*  post receives */
5871:     if (nrecvs) PetscCall(PetscMalloc1(rbs * (rstarts[nrecvs] - rstarts[0]), &rvalues)); /* rstarts can be NULL when nrecvs=0 */
5872:     for (i = 0; i < nrecvs; i++) {
5873:       rowlen = rvalues + rstarts[i] * rbs;
5874:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of indices to be received */
5875:       PetscCallMPI(MPI_Irecv(rowlen, nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5876:     }

5878:     /* pack the outgoing message */
5879:     PetscCall(PetscMalloc2(nsends + 1, &sstartsj, nrecvs + 1, &rstartsj));

5881:     sstartsj[0] = 0;
5882:     rstartsj[0] = 0;
5883:     len         = 0; /* total length of j or a array to be sent */
5884:     if (nsends) {
5885:       k = sstarts[0]; /* ATTENTION: sstarts[0] and rstarts[0] are not necessarily zero */
5886:       PetscCall(PetscMalloc1(sbs * (sstarts[nsends] - sstarts[0]), &svalues));
5887:     }
5888:     for (i = 0; i < nsends; i++) {
5889:       rowlen = svalues + (sstarts[i] - sstarts[0]) * sbs;
5890:       nrows  = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5891:       for (j = 0; j < nrows; j++) {
5892:         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5893:         for (l = 0; l < sbs; l++) {
5894:           PetscCall(MatGetRow_MPIAIJ(B, row + l, &ncols, NULL, NULL)); /* rowlength */

5896:           rowlen[j * sbs + l] = ncols;

5898:           len += ncols;
5899:           PetscCall(MatRestoreRow_MPIAIJ(B, row + l, &ncols, NULL, NULL));
5900:         }
5901:         k++;
5902:       }
5903:       PetscCallMPI(MPI_Isend(rowlen, nrows * sbs, MPIU_INT, sprocs[i], tag, comm, swaits + i));

5905:       sstartsj[i + 1] = len; /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5906:     }
5907:     /* recvs and sends of i-array are completed */
5908:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5909:     PetscCall(PetscFree(svalues));

5911:     /* allocate buffers for sending j and a arrays */
5912:     PetscCall(PetscMalloc1(len + 1, &bufj));
5913:     PetscCall(PetscMalloc1(len + 1, &bufa));

5915:     /* create i-array of B_oth */
5916:     PetscCall(PetscMalloc1(aBn + 2, &b_othi));

5918:     b_othi[0] = 0;
5919:     len       = 0; /* total length of j or a array to be received */
5920:     k         = 0;
5921:     for (i = 0; i < nrecvs; i++) {
5922:       rowlen = rvalues + (rstarts[i] - rstarts[0]) * rbs;
5923:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of rows to be received */
5924:       for (j = 0; j < nrows; j++) {
5925:         b_othi[k + 1] = b_othi[k] + rowlen[j];
5926:         PetscCall(PetscIntSumError(rowlen[j], len, &len));
5927:         k++;
5928:       }
5929:       rstartsj[i + 1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5930:     }
5931:     PetscCall(PetscFree(rvalues));

5933:     /* allocate space for j and a arrays of B_oth */
5934:     PetscCall(PetscMalloc1(b_othi[aBn] + 1, &b_othj));
5935:     PetscCall(PetscMalloc1(b_othi[aBn] + 1, &b_otha));

5937:     /* j-array */
5938:     /*  post receives of j-array */
5939:     for (i = 0; i < nrecvs; i++) {
5940:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5941:       PetscCallMPI(MPI_Irecv(b_othj + rstartsj[i], nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5942:     }

5944:     /* pack the outgoing message j-array */
5945:     if (nsends) k = sstarts[0];
5946:     for (i = 0; i < nsends; i++) {
5947:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5948:       bufJ  = bufj + sstartsj[i];
5949:       for (j = 0; j < nrows; j++) {
5950:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5951:         for (ll = 0; ll < sbs; ll++) {
5952:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5953:           for (l = 0; l < ncols; l++) *bufJ++ = cols[l];
5954:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5955:         }
5956:       }
5957:       PetscCallMPI(MPI_Isend(bufj + sstartsj[i], sstartsj[i + 1] - sstartsj[i], MPIU_INT, sprocs[i], tag, comm, swaits + i));
5958:     }

5960:     /* recvs and sends of j-array are completed */
5961:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5962:   } else if (scall == MAT_REUSE_MATRIX) {
5963:     sstartsj = *startsj_s;
5964:     rstartsj = *startsj_r;
5965:     bufa     = *bufa_ptr;
5966:     b_oth    = (Mat_SeqAIJ *)(*B_oth)->data;
5967:     PetscCall(MatSeqAIJGetArrayWrite(*B_oth, &b_otha));
5968:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not possess an object container");

5970:   /* a-array */
5971:   /*  post receives of a-array */
5972:   for (i = 0; i < nrecvs; i++) {
5973:     nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5974:     PetscCallMPI(MPI_Irecv(b_otha + rstartsj[i], nrows, MPIU_SCALAR, rprocs[i], tag, comm, rwaits + i));
5975:   }

5977:   /* pack the outgoing message a-array */
5978:   if (nsends) k = sstarts[0];
5979:   for (i = 0; i < nsends; i++) {
5980:     nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5981:     bufA  = bufa + sstartsj[i];
5982:     for (j = 0; j < nrows; j++) {
5983:       row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5984:       for (ll = 0; ll < sbs; ll++) {
5985:         PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5986:         for (l = 0; l < ncols; l++) *bufA++ = vals[l];
5987:         PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5988:       }
5989:     }
5990:     PetscCallMPI(MPI_Isend(bufa + sstartsj[i], sstartsj[i + 1] - sstartsj[i], MPIU_SCALAR, sprocs[i], tag, comm, swaits + i));
5991:   }
5992:   /* recvs and sends of a-array are completed */
5993:   if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5994:   PetscCall(PetscFree(reqs));

5996:   if (scall == MAT_INITIAL_MATRIX) {
5997:     /* put together the new matrix */
5998:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, aBn, B->cmap->N, b_othi, b_othj, b_otha, B_oth));

6000:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
6001:     /* Since these are PETSc arrays, change flags to free them as necessary. */
6002:     b_oth          = (Mat_SeqAIJ *)(*B_oth)->data;
6003:     b_oth->free_a  = PETSC_TRUE;
6004:     b_oth->free_ij = PETSC_TRUE;
6005:     b_oth->nonew   = 0;

6007:     PetscCall(PetscFree(bufj));
6008:     if (!startsj_s || !bufa_ptr) {
6009:       PetscCall(PetscFree2(sstartsj, rstartsj));
6010:       PetscCall(PetscFree(bufa_ptr));
6011:     } else {
6012:       *startsj_s = sstartsj;
6013:       *startsj_r = rstartsj;
6014:       *bufa_ptr  = bufa;
6015:     }
6016:   } else if (scall == MAT_REUSE_MATRIX) {
6017:     PetscCall(MatSeqAIJRestoreArrayWrite(*B_oth, &b_otha));
6018:   }

6020:   PetscCall(VecScatterRestoreRemote_Private(ctx, PETSC_TRUE, &nsends, &sstarts, &srow, &sprocs, &sbs));
6021:   PetscCall(VecScatterRestoreRemoteOrdered_Private(ctx, PETSC_FALSE, &nrecvs, &rstarts, NULL, &rprocs, &rbs));
6022:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, B, 0, 0));
6023:   PetscFunctionReturn(PETSC_SUCCESS);
6024: }

6026: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat, MatType, MatReuse, Mat *);
6027: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat, MatType, MatReuse, Mat *);
6028: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJSELL(Mat, MatType, MatReuse, Mat *);
6029: #if defined(PETSC_HAVE_MKL_SPARSE)
6030: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJMKL(Mat, MatType, MatReuse, Mat *);
6031: #endif
6032: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIBAIJ(Mat, MatType, MatReuse, Mat *);
6033: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat, MatType, MatReuse, Mat *);
6034: #if defined(PETSC_HAVE_ELEMENTAL)
6035: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat, MatType, MatReuse, Mat *);
6036: #endif
6037: #if defined(PETSC_HAVE_SCALAPACK)
6038: PETSC_INTERN PetscErrorCode MatConvert_AIJ_ScaLAPACK(Mat, MatType, MatReuse, Mat *);
6039: #endif
6040: #if defined(PETSC_HAVE_HYPRE)
6041: PETSC_INTERN PetscErrorCode MatConvert_AIJ_HYPRE(Mat, MatType, MatReuse, Mat *);
6042: #endif
6043: #if defined(PETSC_HAVE_CUDA)
6044: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
6045: #endif
6046: #if defined(PETSC_HAVE_HIP)
6047: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJHIPSPARSE(Mat, MatType, MatReuse, Mat *);
6048: #endif
6049: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6050: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJKokkos(Mat, MatType, MatReuse, Mat *);
6051: #endif
6052: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISELL(Mat, MatType, MatReuse, Mat *);
6053: PETSC_INTERN PetscErrorCode MatConvert_XAIJ_IS(Mat, MatType, MatReuse, Mat *);
6054: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_IS_XAIJ(Mat);

6056: /*
6057:     Computes (B'*A')' since computing B*A directly is untenable

6059:                n                       p                          p
6060:         [             ]       [             ]         [                 ]
6061:       m [      A      ]  *  n [       B     ]   =   m [         C       ]
6062:         [             ]       [             ]         [                 ]

6064: */
6065: static PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A, Mat B, Mat C)
6066: {
6067:   Mat At, Bt, Ct;

6069:   PetscFunctionBegin;
6070:   PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
6071:   PetscCall(MatTranspose(B, MAT_INITIAL_MATRIX, &Bt));
6072:   PetscCall(MatMatMult(Bt, At, MAT_INITIAL_MATRIX, PETSC_DEFAULT, &Ct));
6073:   PetscCall(MatDestroy(&At));
6074:   PetscCall(MatDestroy(&Bt));
6075:   PetscCall(MatTransposeSetPrecursor(Ct, C));
6076:   PetscCall(MatTranspose(Ct, MAT_REUSE_MATRIX, &C));
6077:   PetscCall(MatDestroy(&Ct));
6078:   PetscFunctionReturn(PETSC_SUCCESS);
6079: }

6081: static PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A, Mat B, PetscReal fill, Mat C)
6082: {
6083:   PetscBool cisdense;

6085:   PetscFunctionBegin;
6086:   PetscCheck(A->cmap->n == B->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "A->cmap->n %" PetscInt_FMT " != B->rmap->n %" PetscInt_FMT, A->cmap->n, B->rmap->n);
6087:   PetscCall(MatSetSizes(C, A->rmap->n, B->cmap->n, A->rmap->N, B->cmap->N));
6088:   PetscCall(MatSetBlockSizesFromMats(C, A, B));
6089:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATMPIDENSE, MATMPIDENSECUDA, MATMPIDENSEHIP, ""));
6090:   if (!cisdense) PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
6091:   PetscCall(MatSetUp(C));

6093:   C->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
6094:   PetscFunctionReturn(PETSC_SUCCESS);
6095: }

6097: static PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ_AB(Mat C)
6098: {
6099:   Mat_Product *product = C->product;
6100:   Mat          A = product->A, B = product->B;

6102:   PetscFunctionBegin;
6103:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
6104:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
6105:   C->ops->matmultsymbolic = MatMatMultSymbolic_MPIDense_MPIAIJ;
6106:   C->ops->productsymbolic = MatProductSymbolic_AB;
6107:   PetscFunctionReturn(PETSC_SUCCESS);
6108: }

6110: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ(Mat C)
6111: {
6112:   Mat_Product *product = C->product;

6114:   PetscFunctionBegin;
6115:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_MPIDense_MPIAIJ_AB(C));
6116:   PetscFunctionReturn(PETSC_SUCCESS);
6117: }

6119: /*
6120:    Merge two sets of sorted nonzeros and return a CSR for the merged (sequential) matrix

6122:   Input Parameters:

6124:     j1,rowBegin1,rowEnd1,jmap1: describe the first set of nonzeros (Set1)
6125:     j2,rowBegin2,rowEnd2,jmap2: describe the second set of nonzeros (Set2)

6127:     mat: both sets' nonzeros are on m rows, where m is the number of local rows of the matrix mat

6129:     For Set1, j1[] contains column indices of the nonzeros.
6130:     For the k-th row (0<=k<m), [rowBegin1[k],rowEnd1[k]) index into j1[] and point to the begin/end nonzero in row k
6131:     respectively (note rowEnd1[k] is not necessarily equal to rwoBegin1[k+1]). Indices in this range of j1[] are sorted,
6132:     but might have repeats. jmap1[t+1] - jmap1[t] is the number of repeats for the t-th unique nonzero in Set1.

6134:     Similar for Set2.

6136:     This routine merges the two sets of nonzeros row by row and removes repeats.

6138:   Output Parameters: (memory is allocated by the caller)

6140:     i[],j[]: the CSR of the merged matrix, which has m rows.
6141:     imap1[]: the k-th unique nonzero in Set1 (k=0,1,...) corresponds to imap1[k]-th unique nonzero in the merged matrix.
6142:     imap2[]: similar to imap1[], but for Set2.
6143:     Note we order nonzeros row-by-row and from left to right.
6144: */
6145: static PetscErrorCode MatMergeEntries_Internal(Mat mat, const PetscInt j1[], const PetscInt j2[], const PetscCount rowBegin1[], const PetscCount rowEnd1[], const PetscCount rowBegin2[], const PetscCount rowEnd2[], const PetscCount jmap1[], const PetscCount jmap2[], PetscCount imap1[], PetscCount imap2[], PetscInt i[], PetscInt j[])
6146: {
6147:   PetscInt   r, m; /* Row index of mat */
6148:   PetscCount t, t1, t2, b1, e1, b2, e2;

6150:   PetscFunctionBegin;
6151:   PetscCall(MatGetLocalSize(mat, &m, NULL));
6152:   t1 = t2 = t = 0; /* Count unique nonzeros of in Set1, Set1 and the merged respectively */
6153:   i[0]        = 0;
6154:   for (r = 0; r < m; r++) { /* Do row by row merging */
6155:     b1 = rowBegin1[r];
6156:     e1 = rowEnd1[r];
6157:     b2 = rowBegin2[r];
6158:     e2 = rowEnd2[r];
6159:     while (b1 < e1 && b2 < e2) {
6160:       if (j1[b1] == j2[b2]) { /* Same column index and hence same nonzero */
6161:         j[t]      = j1[b1];
6162:         imap1[t1] = t;
6163:         imap2[t2] = t;
6164:         b1 += jmap1[t1 + 1] - jmap1[t1]; /* Jump to next unique local nonzero */
6165:         b2 += jmap2[t2 + 1] - jmap2[t2]; /* Jump to next unique remote nonzero */
6166:         t1++;
6167:         t2++;
6168:         t++;
6169:       } else if (j1[b1] < j2[b2]) {
6170:         j[t]      = j1[b1];
6171:         imap1[t1] = t;
6172:         b1 += jmap1[t1 + 1] - jmap1[t1];
6173:         t1++;
6174:         t++;
6175:       } else {
6176:         j[t]      = j2[b2];
6177:         imap2[t2] = t;
6178:         b2 += jmap2[t2 + 1] - jmap2[t2];
6179:         t2++;
6180:         t++;
6181:       }
6182:     }
6183:     /* Merge the remaining in either j1[] or j2[] */
6184:     while (b1 < e1) {
6185:       j[t]      = j1[b1];
6186:       imap1[t1] = t;
6187:       b1 += jmap1[t1 + 1] - jmap1[t1];
6188:       t1++;
6189:       t++;
6190:     }
6191:     while (b2 < e2) {
6192:       j[t]      = j2[b2];
6193:       imap2[t2] = t;
6194:       b2 += jmap2[t2 + 1] - jmap2[t2];
6195:       t2++;
6196:       t++;
6197:     }
6198:     i[r + 1] = t;
6199:   }
6200:   PetscFunctionReturn(PETSC_SUCCESS);
6201: }

6203: /*
6204:   Split nonzeros in a block of local rows into two subsets: those in the diagonal block and those in the off-diagonal block

6206:   Input Parameters:
6207:     mat: an MPI matrix that provides row and column layout information for splitting. Let's say its number of local rows is m.
6208:     n,i[],j[],perm[]: there are n input entries, belonging to m rows. Row/col indices of the entries are stored in i[] and j[]
6209:       respectively, along with a permutation array perm[]. Length of the i[],j[],perm[] arrays is n.

6211:       i[] is already sorted, but within a row, j[] is not sorted and might have repeats.
6212:       i[] might contain negative indices at the beginning, which means the corresponding entries should be ignored in the splitting.

6214:   Output Parameters:
6215:     j[],perm[]: the routine needs to sort j[] within each row along with perm[].
6216:     rowBegin[],rowMid[],rowEnd[]: of length m, and the memory is preallocated and zeroed by the caller.
6217:       They contain indices pointing to j[]. For 0<=r<m, [rowBegin[r],rowMid[r]) point to begin/end entries of row r of the diagonal block,
6218:       and [rowMid[r],rowEnd[r]) point to begin/end entries of row r of the off-diagonal block.

6220:     Aperm[],Ajmap[],Atot,Annz: Arrays are allocated by this routine.
6221:       Atot: number of entries belonging to the diagonal block.
6222:       Annz: number of unique nonzeros belonging to the diagonal block.
6223:       Aperm[Atot] stores values from perm[] for entries belonging to the diagonal block. Length of Aperm[] is Atot, though it may also count
6224:         repeats (i.e., same 'i,j' pair).
6225:       Ajmap[Annz+1] stores the number of repeats of each unique entry belonging to the diagonal block. More precisely, Ajmap[t+1] - Ajmap[t]
6226:         is the number of repeats for the t-th unique entry in the diagonal block. Ajmap[0] is always 0.

6228:       Atot: number of entries belonging to the diagonal block
6229:       Annz: number of unique nonzeros belonging to the diagonal block.

6231:     Bperm[], Bjmap[], Btot, Bnnz are similar but for the off-diagonal block.

6233:     Aperm[],Bperm[],Ajmap[] and Bjmap[] are allocated separately by this routine with PetscMalloc1().
6234: */
6235: static PetscErrorCode MatSplitEntries_Internal(Mat mat, PetscCount n, const PetscInt i[], PetscInt j[], PetscCount perm[], PetscCount rowBegin[], PetscCount rowMid[], PetscCount rowEnd[], PetscCount *Atot_, PetscCount **Aperm_, PetscCount *Annz_, PetscCount **Ajmap_, PetscCount *Btot_, PetscCount **Bperm_, PetscCount *Bnnz_, PetscCount **Bjmap_)
6236: {
6237:   PetscInt    cstart, cend, rstart, rend, row, col;
6238:   PetscCount  Atot = 0, Btot = 0; /* Total number of nonzeros in the diagonal and off-diagonal blocks */
6239:   PetscCount  Annz = 0, Bnnz = 0; /* Number of unique nonzeros in the diagonal and off-diagonal blocks */
6240:   PetscCount  k, m, p, q, r, s, mid;
6241:   PetscCount *Aperm, *Bperm, *Ajmap, *Bjmap;

6243:   PetscFunctionBegin;
6244:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6245:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6246:   m = rend - rstart;

6248:   /* Skip negative rows */
6249:   for (k = 0; k < n; k++)
6250:     if (i[k] >= 0) break;

6252:   /* Process [k,n): sort and partition each local row into diag and offdiag portions,
6253:      fill rowBegin[], rowMid[], rowEnd[], and count Atot, Btot, Annz, Bnnz.
6254:   */
6255:   while (k < n) {
6256:     row = i[k];
6257:     /* Entries in [k,s) are in one row. Shift diagonal block col indices so that diag is ahead of offdiag after sorting the row */
6258:     for (s = k; s < n; s++)
6259:       if (i[s] != row) break;

6261:     /* Shift diag columns to range of [-PETSC_MAX_INT, -1] */
6262:     for (p = k; p < s; p++) {
6263:       if (j[p] >= cstart && j[p] < cend) j[p] -= PETSC_MAX_INT;
6264:       else PetscAssert((j[p] >= 0) && (j[p] <= mat->cmap->N), PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column index %" PetscInt_FMT " is out of range", j[p]);
6265:     }
6266:     PetscCall(PetscSortIntWithCountArray(s - k, j + k, perm + k));
6267:     PetscCall(PetscSortedIntUpperBound(j, k, s, -1, &mid)); /* Separate [k,s) into [k,mid) for diag and [mid,s) for offdiag */
6268:     rowBegin[row - rstart] = k;
6269:     rowMid[row - rstart]   = mid;
6270:     rowEnd[row - rstart]   = s;

6272:     /* Count nonzeros of this diag/offdiag row, which might have repeats */
6273:     Atot += mid - k;
6274:     Btot += s - mid;

6276:     /* Count unique nonzeros of this diag row */
6277:     for (p = k; p < mid;) {
6278:       col = j[p];
6279:       do {
6280:         j[p] += PETSC_MAX_INT; /* Revert the modified diagonal indices */
6281:         p++;
6282:       } while (p < mid && j[p] == col);
6283:       Annz++;
6284:     }

6286:     /* Count unique nonzeros of this offdiag row */
6287:     for (p = mid; p < s;) {
6288:       col = j[p];
6289:       do {
6290:         p++;
6291:       } while (p < s && j[p] == col);
6292:       Bnnz++;
6293:     }
6294:     k = s;
6295:   }

6297:   /* Allocation according to Atot, Btot, Annz, Bnnz */
6298:   PetscCall(PetscMalloc1(Atot, &Aperm));
6299:   PetscCall(PetscMalloc1(Btot, &Bperm));
6300:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap));
6301:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap));

6303:   /* Re-scan indices and copy diag/offdiag permutation indices to Aperm, Bperm and also fill Ajmap and Bjmap */
6304:   Ajmap[0] = Bjmap[0] = Atot = Btot = Annz = Bnnz = 0;
6305:   for (r = 0; r < m; r++) {
6306:     k   = rowBegin[r];
6307:     mid = rowMid[r];
6308:     s   = rowEnd[r];
6309:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Aperm, Atot), PetscSafePointerPlusOffset(perm, k), mid - k));
6310:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Bperm, Btot), PetscSafePointerPlusOffset(perm, mid), s - mid));
6311:     Atot += mid - k;
6312:     Btot += s - mid;

6314:     /* Scan column indices in this row and find out how many repeats each unique nonzero has */
6315:     for (p = k; p < mid;) {
6316:       col = j[p];
6317:       q   = p;
6318:       do {
6319:         p++;
6320:       } while (p < mid && j[p] == col);
6321:       Ajmap[Annz + 1] = Ajmap[Annz] + (p - q);
6322:       Annz++;
6323:     }

6325:     for (p = mid; p < s;) {
6326:       col = j[p];
6327:       q   = p;
6328:       do {
6329:         p++;
6330:       } while (p < s && j[p] == col);
6331:       Bjmap[Bnnz + 1] = Bjmap[Bnnz] + (p - q);
6332:       Bnnz++;
6333:     }
6334:   }
6335:   /* Output */
6336:   *Aperm_ = Aperm;
6337:   *Annz_  = Annz;
6338:   *Atot_  = Atot;
6339:   *Ajmap_ = Ajmap;
6340:   *Bperm_ = Bperm;
6341:   *Bnnz_  = Bnnz;
6342:   *Btot_  = Btot;
6343:   *Bjmap_ = Bjmap;
6344:   PetscFunctionReturn(PETSC_SUCCESS);
6345: }

6347: /*
6348:   Expand the jmap[] array to make a new one in view of nonzeros in the merged matrix

6350:   Input Parameters:
6351:     nnz1: number of unique nonzeros in a set that was used to produce imap[], jmap[]
6352:     nnz:  number of unique nonzeros in the merged matrix
6353:     imap[nnz1]: i-th nonzero in the set is the imap[i]-th nonzero in the merged matrix
6354:     jmap[nnz1+1]: i-th nonzero in the set has jmap[i+1] - jmap[i] repeats in the set

6356:   Output Parameter: (memory is allocated by the caller)
6357:     jmap_new[nnz+1]: i-th nonzero in the merged matrix has jmap_new[i+1] - jmap_new[i] repeats in the set

6359:   Example:
6360:     nnz1 = 4
6361:     nnz  = 6
6362:     imap = [1,3,4,5]
6363:     jmap = [0,3,5,6,7]
6364:    then,
6365:     jmap_new = [0,0,3,3,5,6,7]
6366: */
6367: static PetscErrorCode ExpandJmap_Internal(PetscCount nnz1, PetscCount nnz, const PetscCount imap[], const PetscCount jmap[], PetscCount jmap_new[])
6368: {
6369:   PetscCount k, p;

6371:   PetscFunctionBegin;
6372:   jmap_new[0] = 0;
6373:   p           = nnz;                /* p loops over jmap_new[] backwards */
6374:   for (k = nnz1 - 1; k >= 0; k--) { /* k loops over imap[] */
6375:     for (; p > imap[k]; p--) jmap_new[p] = jmap[k + 1];
6376:   }
6377:   for (; p >= 0; p--) jmap_new[p] = jmap[0];
6378:   PetscFunctionReturn(PETSC_SUCCESS);
6379: }

6381: static PetscErrorCode MatCOOStructDestroy_MPIAIJ(void *data)
6382: {
6383:   MatCOOStruct_MPIAIJ *coo = (MatCOOStruct_MPIAIJ *)data;

6385:   PetscFunctionBegin;
6386:   PetscCall(PetscSFDestroy(&coo->sf));
6387:   PetscCall(PetscFree(coo->Aperm1));
6388:   PetscCall(PetscFree(coo->Bperm1));
6389:   PetscCall(PetscFree(coo->Ajmap1));
6390:   PetscCall(PetscFree(coo->Bjmap1));
6391:   PetscCall(PetscFree(coo->Aimap2));
6392:   PetscCall(PetscFree(coo->Bimap2));
6393:   PetscCall(PetscFree(coo->Aperm2));
6394:   PetscCall(PetscFree(coo->Bperm2));
6395:   PetscCall(PetscFree(coo->Ajmap2));
6396:   PetscCall(PetscFree(coo->Bjmap2));
6397:   PetscCall(PetscFree(coo->Cperm1));
6398:   PetscCall(PetscFree2(coo->sendbuf, coo->recvbuf));
6399:   PetscCall(PetscFree(coo));
6400:   PetscFunctionReturn(PETSC_SUCCESS);
6401: }

6403: PetscErrorCode MatSetPreallocationCOO_MPIAIJ(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
6404: {
6405:   MPI_Comm             comm;
6406:   PetscMPIInt          rank, size;
6407:   PetscInt             m, n, M, N, rstart, rend, cstart, cend; /* Sizes, indices of row/col, therefore with type PetscInt */
6408:   PetscCount           k, p, q, rem;                           /* Loop variables over coo arrays */
6409:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6410:   PetscContainer       container;
6411:   MatCOOStruct_MPIAIJ *coo;

6413:   PetscFunctionBegin;
6414:   PetscCall(PetscFree(mpiaij->garray));
6415:   PetscCall(VecDestroy(&mpiaij->lvec));
6416: #if defined(PETSC_USE_CTABLE)
6417:   PetscCall(PetscHMapIDestroy(&mpiaij->colmap));
6418: #else
6419:   PetscCall(PetscFree(mpiaij->colmap));
6420: #endif
6421:   PetscCall(VecScatterDestroy(&mpiaij->Mvctx));
6422:   mat->assembled     = PETSC_FALSE;
6423:   mat->was_assembled = PETSC_FALSE;

6425:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
6426:   PetscCallMPI(MPI_Comm_size(comm, &size));
6427:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
6428:   PetscCall(PetscLayoutSetUp(mat->rmap));
6429:   PetscCall(PetscLayoutSetUp(mat->cmap));
6430:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6431:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6432:   PetscCall(MatGetLocalSize(mat, &m, &n));
6433:   PetscCall(MatGetSize(mat, &M, &N));

6435:   /* Sort (i,j) by row along with a permutation array, so that the to-be-ignored */
6436:   /* entries come first, then local rows, then remote rows.                     */
6437:   PetscCount n1 = coo_n, *perm1;
6438:   PetscInt  *i1 = coo_i, *j1 = coo_j;

6440:   PetscCall(PetscMalloc1(n1, &perm1));
6441:   for (k = 0; k < n1; k++) perm1[k] = k;

6443:   /* Manipulate indices so that entries with negative row or col indices will have smallest
6444:      row indices, local entries will have greater but negative row indices, and remote entries
6445:      will have positive row indices.
6446:   */
6447:   for (k = 0; k < n1; k++) {
6448:     if (i1[k] < 0 || j1[k] < 0) i1[k] = PETSC_MIN_INT;                /* e.g., -2^31, minimal to move them ahead */
6449:     else if (i1[k] >= rstart && i1[k] < rend) i1[k] -= PETSC_MAX_INT; /* e.g., minus 2^31-1 to shift local rows to range of [-PETSC_MAX_INT, -1] */
6450:     else {
6451:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "MAT_NO_OFF_PROC_ENTRIES is set but insert to remote rows");
6452:       if (mpiaij->donotstash) i1[k] = PETSC_MIN_INT; /* Ignore offproc entries as if they had negative indices */
6453:     }
6454:   }

6456:   /* Sort by row; after that, [0,k) have ignored entries, [k,rem) have local rows and [rem,n1) have remote rows */
6457:   PetscCall(PetscSortIntWithIntCountArrayPair(n1, i1, j1, perm1));

6459:   /* Advance k to the first entry we need to take care of */
6460:   for (k = 0; k < n1; k++)
6461:     if (i1[k] > PETSC_MIN_INT) break;
6462:   PetscInt i1start = k;

6464:   PetscCall(PetscSortedIntUpperBound(i1, k, n1, rend - 1 - PETSC_MAX_INT, &rem)); /* rem is upper bound of the last local row */
6465:   for (; k < rem; k++) i1[k] += PETSC_MAX_INT;                                    /* Revert row indices of local rows*/

6467:   /*           Send remote rows to their owner                                  */
6468:   /* Find which rows should be sent to which remote ranks*/
6469:   PetscInt        nsend = 0; /* Number of MPI ranks to send data to */
6470:   PetscMPIInt    *sendto;    /* [nsend], storing remote ranks */
6471:   PetscInt       *nentries;  /* [nsend], storing number of entries sent to remote ranks; Assume PetscInt is big enough for this count, and error if not */
6472:   const PetscInt *ranges;
6473:   PetscInt        maxNsend = size >= 128 ? 128 : size; /* Assume max 128 neighbors; realloc when needed */

6475:   PetscCall(PetscLayoutGetRanges(mat->rmap, &ranges));
6476:   PetscCall(PetscMalloc2(maxNsend, &sendto, maxNsend, &nentries));
6477:   for (k = rem; k < n1;) {
6478:     PetscMPIInt owner;
6479:     PetscInt    firstRow, lastRow;

6481:     /* Locate a row range */
6482:     firstRow = i1[k]; /* first row of this owner */
6483:     PetscCall(PetscLayoutFindOwner(mat->rmap, firstRow, &owner));
6484:     lastRow = ranges[owner + 1] - 1; /* last row of this owner */

6486:     /* Find the first index 'p' in [k,n) with i[p] belonging to next owner */
6487:     PetscCall(PetscSortedIntUpperBound(i1, k, n1, lastRow, &p));

6489:     /* All entries in [k,p) belong to this remote owner */
6490:     if (nsend >= maxNsend) { /* Double the remote ranks arrays if not long enough */
6491:       PetscMPIInt *sendto2;
6492:       PetscInt    *nentries2;
6493:       PetscInt     maxNsend2 = (maxNsend <= size / 2) ? maxNsend * 2 : size;

6495:       PetscCall(PetscMalloc2(maxNsend2, &sendto2, maxNsend2, &nentries2));
6496:       PetscCall(PetscArraycpy(sendto2, sendto, maxNsend));
6497:       PetscCall(PetscArraycpy(nentries2, nentries2, maxNsend + 1));
6498:       PetscCall(PetscFree2(sendto, nentries2));
6499:       sendto   = sendto2;
6500:       nentries = nentries2;
6501:       maxNsend = maxNsend2;
6502:     }
6503:     sendto[nsend]   = owner;
6504:     nentries[nsend] = p - k;
6505:     PetscCall(PetscCountCast(p - k, &nentries[nsend]));
6506:     nsend++;
6507:     k = p;
6508:   }

6510:   /* Build 1st SF to know offsets on remote to send data */
6511:   PetscSF      sf1;
6512:   PetscInt     nroots = 1, nroots2 = 0;
6513:   PetscInt     nleaves = nsend, nleaves2 = 0;
6514:   PetscInt    *offsets;
6515:   PetscSFNode *iremote;

6517:   PetscCall(PetscSFCreate(comm, &sf1));
6518:   PetscCall(PetscMalloc1(nsend, &iremote));
6519:   PetscCall(PetscMalloc1(nsend, &offsets));
6520:   for (k = 0; k < nsend; k++) {
6521:     iremote[k].rank  = sendto[k];
6522:     iremote[k].index = 0;
6523:     nleaves2 += nentries[k];
6524:     PetscCheck(nleaves2 >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF leaves is too large for PetscInt");
6525:   }
6526:   PetscCall(PetscSFSetGraph(sf1, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
6527:   PetscCall(PetscSFFetchAndOpWithMemTypeBegin(sf1, MPIU_INT, PETSC_MEMTYPE_HOST, &nroots2 /*rootdata*/, PETSC_MEMTYPE_HOST, nentries /*leafdata*/, PETSC_MEMTYPE_HOST, offsets /*leafupdate*/, MPI_SUM));
6528:   PetscCall(PetscSFFetchAndOpEnd(sf1, MPIU_INT, &nroots2, nentries, offsets, MPI_SUM)); /* Would nroots2 overflow, we check offsets[] below */
6529:   PetscCall(PetscSFDestroy(&sf1));
6530:   PetscAssert(nleaves2 == n1 - rem, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nleaves2 %" PetscInt_FMT " != number of remote entries %" PetscCount_FMT, nleaves2, n1 - rem);

6532:   /* Build 2nd SF to send remote COOs to their owner */
6533:   PetscSF sf2;
6534:   nroots  = nroots2;
6535:   nleaves = nleaves2;
6536:   PetscCall(PetscSFCreate(comm, &sf2));
6537:   PetscCall(PetscSFSetFromOptions(sf2));
6538:   PetscCall(PetscMalloc1(nleaves, &iremote));
6539:   p = 0;
6540:   for (k = 0; k < nsend; k++) {
6541:     PetscCheck(offsets[k] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF roots is too large for PetscInt");
6542:     for (q = 0; q < nentries[k]; q++, p++) {
6543:       iremote[p].rank  = sendto[k];
6544:       iremote[p].index = offsets[k] + q;
6545:     }
6546:   }
6547:   PetscCall(PetscSFSetGraph(sf2, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

6549:   /* Send the remote COOs to their owner */
6550:   PetscInt    n2 = nroots, *i2, *j2; /* Buffers for received COOs from other ranks, along with a permutation array */
6551:   PetscCount *perm2;                 /* Though PetscInt is enough for remote entries, we use PetscCount here as we want to reuse MatSplitEntries_Internal() */
6552:   PetscCall(PetscMalloc3(n2, &i2, n2, &j2, n2, &perm2));
6553:   PetscAssert(rem == 0 || i1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6554:   PetscAssert(rem == 0 || j1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6555:   PetscInt *i1prem = i1 ? i1 + rem : NULL; /* silence ubsan warnings about pointer arithmetic on null pointer */
6556:   PetscInt *j1prem = j1 ? j1 + rem : NULL;
6557:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, i1prem, PETSC_MEMTYPE_HOST, i2, MPI_REPLACE));
6558:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, i1prem, i2, MPI_REPLACE));
6559:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, j1prem, PETSC_MEMTYPE_HOST, j2, MPI_REPLACE));
6560:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, j1prem, j2, MPI_REPLACE));

6562:   PetscCall(PetscFree(offsets));
6563:   PetscCall(PetscFree2(sendto, nentries));

6565:   /* Sort received COOs by row along with the permutation array     */
6566:   for (k = 0; k < n2; k++) perm2[k] = k;
6567:   PetscCall(PetscSortIntWithIntCountArrayPair(n2, i2, j2, perm2));

6569:   /* sf2 only sends contiguous leafdata to contiguous rootdata. We record the permutation which will be used to fill leafdata */
6570:   PetscCount *Cperm1;
6571:   PetscAssert(rem == 0 || perm1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6572:   PetscCount *perm1prem = perm1 ? perm1 + rem : NULL;
6573:   PetscCall(PetscMalloc1(nleaves, &Cperm1));
6574:   PetscCall(PetscArraycpy(Cperm1, perm1prem, nleaves));

6576:   /* Support for HYPRE matrices, kind of a hack.
6577:      Swap min column with diagonal so that diagonal values will go first */
6578:   PetscBool   hypre;
6579:   const char *name;
6580:   PetscCall(PetscObjectGetName((PetscObject)mat, &name));
6581:   PetscCall(PetscStrcmp("_internal_COO_mat_for_hypre", name, &hypre));
6582:   if (hypre) {
6583:     PetscInt *minj;
6584:     PetscBT   hasdiag;

6586:     PetscCall(PetscBTCreate(m, &hasdiag));
6587:     PetscCall(PetscMalloc1(m, &minj));
6588:     for (k = 0; k < m; k++) minj[k] = PETSC_MAX_INT;
6589:     for (k = i1start; k < rem; k++) {
6590:       if (j1[k] < cstart || j1[k] >= cend) continue;
6591:       const PetscInt rindex = i1[k] - rstart;
6592:       if ((j1[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6593:       minj[rindex] = PetscMin(minj[rindex], j1[k]);
6594:     }
6595:     for (k = 0; k < n2; k++) {
6596:       if (j2[k] < cstart || j2[k] >= cend) continue;
6597:       const PetscInt rindex = i2[k] - rstart;
6598:       if ((j2[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6599:       minj[rindex] = PetscMin(minj[rindex], j2[k]);
6600:     }
6601:     for (k = i1start; k < rem; k++) {
6602:       const PetscInt rindex = i1[k] - rstart;
6603:       if (j1[k] < cstart || j1[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6604:       if (j1[k] == minj[rindex]) j1[k] = i1[k] + (cstart - rstart);
6605:       else if ((j1[k] - cstart) == rindex) j1[k] = minj[rindex];
6606:     }
6607:     for (k = 0; k < n2; k++) {
6608:       const PetscInt rindex = i2[k] - rstart;
6609:       if (j2[k] < cstart || j2[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6610:       if (j2[k] == minj[rindex]) j2[k] = i2[k] + (cstart - rstart);
6611:       else if ((j2[k] - cstart) == rindex) j2[k] = minj[rindex];
6612:     }
6613:     PetscCall(PetscBTDestroy(&hasdiag));
6614:     PetscCall(PetscFree(minj));
6615:   }

6617:   /* Split local COOs and received COOs into diag/offdiag portions */
6618:   PetscCount *rowBegin1, *rowMid1, *rowEnd1;
6619:   PetscCount *Ajmap1, *Aperm1, *Bjmap1, *Bperm1;
6620:   PetscCount  Annz1, Bnnz1, Atot1, Btot1;
6621:   PetscCount *rowBegin2, *rowMid2, *rowEnd2;
6622:   PetscCount *Ajmap2, *Aperm2, *Bjmap2, *Bperm2;
6623:   PetscCount  Annz2, Bnnz2, Atot2, Btot2;

6625:   PetscCall(PetscCalloc3(m, &rowBegin1, m, &rowMid1, m, &rowEnd1));
6626:   PetscCall(PetscCalloc3(m, &rowBegin2, m, &rowMid2, m, &rowEnd2));
6627:   PetscCall(MatSplitEntries_Internal(mat, rem, i1, j1, perm1, rowBegin1, rowMid1, rowEnd1, &Atot1, &Aperm1, &Annz1, &Ajmap1, &Btot1, &Bperm1, &Bnnz1, &Bjmap1));
6628:   PetscCall(MatSplitEntries_Internal(mat, n2, i2, j2, perm2, rowBegin2, rowMid2, rowEnd2, &Atot2, &Aperm2, &Annz2, &Ajmap2, &Btot2, &Bperm2, &Bnnz2, &Bjmap2));

6630:   /* Merge local COOs with received COOs: diag with diag, offdiag with offdiag */
6631:   PetscInt *Ai, *Bi;
6632:   PetscInt *Aj, *Bj;

6634:   PetscCall(PetscMalloc1(m + 1, &Ai));
6635:   PetscCall(PetscMalloc1(m + 1, &Bi));
6636:   PetscCall(PetscMalloc1(Annz1 + Annz2, &Aj)); /* Since local and remote entries might have dups, we might allocate excess memory */
6637:   PetscCall(PetscMalloc1(Bnnz1 + Bnnz2, &Bj));

6639:   PetscCount *Aimap1, *Bimap1, *Aimap2, *Bimap2;
6640:   PetscCall(PetscMalloc1(Annz1, &Aimap1));
6641:   PetscCall(PetscMalloc1(Bnnz1, &Bimap1));
6642:   PetscCall(PetscMalloc1(Annz2, &Aimap2));
6643:   PetscCall(PetscMalloc1(Bnnz2, &Bimap2));

6645:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowBegin1, rowMid1, rowBegin2, rowMid2, Ajmap1, Ajmap2, Aimap1, Aimap2, Ai, Aj));
6646:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowMid1, rowEnd1, rowMid2, rowEnd2, Bjmap1, Bjmap2, Bimap1, Bimap2, Bi, Bj));

6648:   /* Expand Ajmap1/Bjmap1 to make them based off nonzeros in A/B, since we     */
6649:   /* expect nonzeros in A/B most likely have local contributing entries        */
6650:   PetscInt    Annz = Ai[m];
6651:   PetscInt    Bnnz = Bi[m];
6652:   PetscCount *Ajmap1_new, *Bjmap1_new;

6654:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap1_new));
6655:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap1_new));

6657:   PetscCall(ExpandJmap_Internal(Annz1, Annz, Aimap1, Ajmap1, Ajmap1_new));
6658:   PetscCall(ExpandJmap_Internal(Bnnz1, Bnnz, Bimap1, Bjmap1, Bjmap1_new));

6660:   PetscCall(PetscFree(Aimap1));
6661:   PetscCall(PetscFree(Ajmap1));
6662:   PetscCall(PetscFree(Bimap1));
6663:   PetscCall(PetscFree(Bjmap1));
6664:   PetscCall(PetscFree3(rowBegin1, rowMid1, rowEnd1));
6665:   PetscCall(PetscFree3(rowBegin2, rowMid2, rowEnd2));
6666:   PetscCall(PetscFree(perm1));
6667:   PetscCall(PetscFree3(i2, j2, perm2));

6669:   Ajmap1 = Ajmap1_new;
6670:   Bjmap1 = Bjmap1_new;

6672:   /* Reallocate Aj, Bj once we know actual numbers of unique nonzeros in A and B */
6673:   if (Annz < Annz1 + Annz2) {
6674:     PetscInt *Aj_new;
6675:     PetscCall(PetscMalloc1(Annz, &Aj_new));
6676:     PetscCall(PetscArraycpy(Aj_new, Aj, Annz));
6677:     PetscCall(PetscFree(Aj));
6678:     Aj = Aj_new;
6679:   }

6681:   if (Bnnz < Bnnz1 + Bnnz2) {
6682:     PetscInt *Bj_new;
6683:     PetscCall(PetscMalloc1(Bnnz, &Bj_new));
6684:     PetscCall(PetscArraycpy(Bj_new, Bj, Bnnz));
6685:     PetscCall(PetscFree(Bj));
6686:     Bj = Bj_new;
6687:   }

6689:   /* Create new submatrices for on-process and off-process coupling                  */
6690:   PetscScalar     *Aa, *Ba;
6691:   MatType          rtype;
6692:   Mat_SeqAIJ      *a, *b;
6693:   PetscObjectState state;
6694:   PetscCall(PetscCalloc1(Annz, &Aa)); /* Zero matrix on device */
6695:   PetscCall(PetscCalloc1(Bnnz, &Ba));
6696:   /* make Aj[] local, i.e, based off the start column of the diagonal portion */
6697:   if (cstart) {
6698:     for (k = 0; k < Annz; k++) Aj[k] -= cstart;
6699:   }

6701:   PetscCall(MatGetRootType_Private(mat, &rtype));

6703:   MatSeqXAIJGetOptions_Private(mpiaij->A);
6704:   PetscCall(MatDestroy(&mpiaij->A));
6705:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, Ai, Aj, Aa, &mpiaij->A));
6706:   PetscCall(MatSetBlockSizesFromMats(mpiaij->A, mat, mat));
6707:   MatSeqXAIJRestoreOptions_Private(mpiaij->A);

6709:   MatSeqXAIJGetOptions_Private(mpiaij->B);
6710:   PetscCall(MatDestroy(&mpiaij->B));
6711:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, mat->cmap->N, Bi, Bj, Ba, &mpiaij->B));
6712:   PetscCall(MatSetBlockSizesFromMats(mpiaij->B, mat, mat));
6713:   MatSeqXAIJRestoreOptions_Private(mpiaij->B);

6715:   PetscCall(MatSetUpMultiply_MPIAIJ(mat));
6716:   mat->was_assembled = PETSC_TRUE; // was_assembled in effect means the Mvctx is built; doing so avoids redundant MatSetUpMultiply_MPIAIJ
6717:   state              = mpiaij->A->nonzerostate + mpiaij->B->nonzerostate;
6718:   PetscCall(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));

6720:   a               = (Mat_SeqAIJ *)mpiaij->A->data;
6721:   b               = (Mat_SeqAIJ *)mpiaij->B->data;
6722:   a->singlemalloc = b->singlemalloc = PETSC_FALSE; /* Let newmat own Ai,Aj,Aa,Bi,Bj,Ba */
6723:   a->free_a = b->free_a = PETSC_TRUE;
6724:   a->free_ij = b->free_ij = PETSC_TRUE;

6726:   /* conversion must happen AFTER multiply setup */
6727:   PetscCall(MatConvert(mpiaij->A, rtype, MAT_INPLACE_MATRIX, &mpiaij->A));
6728:   PetscCall(MatConvert(mpiaij->B, rtype, MAT_INPLACE_MATRIX, &mpiaij->B));
6729:   PetscCall(VecDestroy(&mpiaij->lvec));
6730:   PetscCall(MatCreateVecs(mpiaij->B, &mpiaij->lvec, NULL));

6732:   // Put the COO struct in a container and then attach that to the matrix
6733:   PetscCall(PetscMalloc1(1, &coo));
6734:   coo->n       = coo_n;
6735:   coo->sf      = sf2;
6736:   coo->sendlen = nleaves;
6737:   coo->recvlen = nroots;
6738:   coo->Annz    = Annz;
6739:   coo->Bnnz    = Bnnz;
6740:   coo->Annz2   = Annz2;
6741:   coo->Bnnz2   = Bnnz2;
6742:   coo->Atot1   = Atot1;
6743:   coo->Atot2   = Atot2;
6744:   coo->Btot1   = Btot1;
6745:   coo->Btot2   = Btot2;
6746:   coo->Ajmap1  = Ajmap1;
6747:   coo->Aperm1  = Aperm1;
6748:   coo->Bjmap1  = Bjmap1;
6749:   coo->Bperm1  = Bperm1;
6750:   coo->Aimap2  = Aimap2;
6751:   coo->Ajmap2  = Ajmap2;
6752:   coo->Aperm2  = Aperm2;
6753:   coo->Bimap2  = Bimap2;
6754:   coo->Bjmap2  = Bjmap2;
6755:   coo->Bperm2  = Bperm2;
6756:   coo->Cperm1  = Cperm1;
6757:   // Allocate in preallocation. If not used, it has zero cost on host
6758:   PetscCall(PetscMalloc2(coo->sendlen, &coo->sendbuf, coo->recvlen, &coo->recvbuf));
6759:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
6760:   PetscCall(PetscContainerSetPointer(container, coo));
6761:   PetscCall(PetscContainerSetUserDestroy(container, MatCOOStructDestroy_MPIAIJ));
6762:   PetscCall(PetscObjectCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject)container));
6763:   PetscCall(PetscContainerDestroy(&container));
6764:   PetscFunctionReturn(PETSC_SUCCESS);
6765: }

6767: static PetscErrorCode MatSetValuesCOO_MPIAIJ(Mat mat, const PetscScalar v[], InsertMode imode)
6768: {
6769:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6770:   Mat                  A = mpiaij->A, B = mpiaij->B;
6771:   PetscScalar         *Aa, *Ba;
6772:   PetscScalar         *sendbuf, *recvbuf;
6773:   const PetscCount    *Ajmap1, *Ajmap2, *Aimap2;
6774:   const PetscCount    *Bjmap1, *Bjmap2, *Bimap2;
6775:   const PetscCount    *Aperm1, *Aperm2, *Bperm1, *Bperm2;
6776:   const PetscCount    *Cperm1;
6777:   PetscContainer       container;
6778:   MatCOOStruct_MPIAIJ *coo;

6780:   PetscFunctionBegin;
6781:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container));
6782:   PetscCheck(container, PetscObjectComm((PetscObject)mat), PETSC_ERR_PLIB, "Not found MatCOOStruct on this matrix");
6783:   PetscCall(PetscContainerGetPointer(container, (void **)&coo));
6784:   sendbuf = coo->sendbuf;
6785:   recvbuf = coo->recvbuf;
6786:   Ajmap1  = coo->Ajmap1;
6787:   Ajmap2  = coo->Ajmap2;
6788:   Aimap2  = coo->Aimap2;
6789:   Bjmap1  = coo->Bjmap1;
6790:   Bjmap2  = coo->Bjmap2;
6791:   Bimap2  = coo->Bimap2;
6792:   Aperm1  = coo->Aperm1;
6793:   Aperm2  = coo->Aperm2;
6794:   Bperm1  = coo->Bperm1;
6795:   Bperm2  = coo->Bperm2;
6796:   Cperm1  = coo->Cperm1;

6798:   PetscCall(MatSeqAIJGetArray(A, &Aa)); /* Might read and write matrix values */
6799:   PetscCall(MatSeqAIJGetArray(B, &Ba));

6801:   /* Pack entries to be sent to remote */
6802:   for (PetscCount i = 0; i < coo->sendlen; i++) sendbuf[i] = v[Cperm1[i]];

6804:   /* Send remote entries to their owner and overlap the communication with local computation */
6805:   PetscCall(PetscSFReduceWithMemTypeBegin(coo->sf, MPIU_SCALAR, PETSC_MEMTYPE_HOST, sendbuf, PETSC_MEMTYPE_HOST, recvbuf, MPI_REPLACE));
6806:   /* Add local entries to A and B */
6807:   for (PetscCount i = 0; i < coo->Annz; i++) { /* All nonzeros in A are either zero'ed or added with a value (i.e., initialized) */
6808:     PetscScalar sum = 0.0;                     /* Do partial summation first to improve numerical stability */
6809:     for (PetscCount k = Ajmap1[i]; k < Ajmap1[i + 1]; k++) sum += v[Aperm1[k]];
6810:     Aa[i] = (imode == INSERT_VALUES ? 0.0 : Aa[i]) + sum;
6811:   }
6812:   for (PetscCount i = 0; i < coo->Bnnz; i++) {
6813:     PetscScalar sum = 0.0;
6814:     for (PetscCount k = Bjmap1[i]; k < Bjmap1[i + 1]; k++) sum += v[Bperm1[k]];
6815:     Ba[i] = (imode == INSERT_VALUES ? 0.0 : Ba[i]) + sum;
6816:   }
6817:   PetscCall(PetscSFReduceEnd(coo->sf, MPIU_SCALAR, sendbuf, recvbuf, MPI_REPLACE));

6819:   /* Add received remote entries to A and B */
6820:   for (PetscCount i = 0; i < coo->Annz2; i++) {
6821:     for (PetscCount k = Ajmap2[i]; k < Ajmap2[i + 1]; k++) Aa[Aimap2[i]] += recvbuf[Aperm2[k]];
6822:   }
6823:   for (PetscCount i = 0; i < coo->Bnnz2; i++) {
6824:     for (PetscCount k = Bjmap2[i]; k < Bjmap2[i + 1]; k++) Ba[Bimap2[i]] += recvbuf[Bperm2[k]];
6825:   }
6826:   PetscCall(MatSeqAIJRestoreArray(A, &Aa));
6827:   PetscCall(MatSeqAIJRestoreArray(B, &Ba));
6828:   PetscFunctionReturn(PETSC_SUCCESS);
6829: }

6831: /*MC
6832:    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.

6834:    Options Database Keys:
6835: . -mat_type mpiaij - sets the matrix type to `MATMPIAIJ` during a call to `MatSetFromOptions()`

6837:    Level: beginner

6839:    Notes:
6840:    `MatSetValues()` may be called for this matrix type with a `NULL` argument for the numerical values,
6841:     in this case the values associated with the rows and columns one passes in are set to zero
6842:     in the matrix

6844:     `MatSetOptions`(,`MAT_STRUCTURE_ONLY`,`PETSC_TRUE`) may be called for this matrix type. In this no
6845:     space is allocated for the nonzero entries and any entries passed with `MatSetValues()` are ignored

6847: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJ`, `MATAIJ`, `MatCreateAIJ()`
6848: M*/
6849: PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
6850: {
6851:   Mat_MPIAIJ *b;
6852:   PetscMPIInt size;

6854:   PetscFunctionBegin;
6855:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

6857:   PetscCall(PetscNew(&b));
6858:   B->data       = (void *)b;
6859:   B->ops[0]     = MatOps_Values;
6860:   B->assembled  = PETSC_FALSE;
6861:   B->insertmode = NOT_SET_VALUES;
6862:   b->size       = size;

6864:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)B), &b->rank));

6866:   /* build cache for off array entries formed */
6867:   PetscCall(MatStashCreate_Private(PetscObjectComm((PetscObject)B), 1, &B->stash));

6869:   b->donotstash  = PETSC_FALSE;
6870:   b->colmap      = NULL;
6871:   b->garray      = NULL;
6872:   b->roworiented = PETSC_TRUE;

6874:   /* stuff used for matrix vector multiply */
6875:   b->lvec  = NULL;
6876:   b->Mvctx = NULL;

6878:   /* stuff for MatGetRow() */
6879:   b->rowindices   = NULL;
6880:   b->rowvalues    = NULL;
6881:   b->getrowactive = PETSC_FALSE;

6883:   /* flexible pointer used in CUSPARSE classes */
6884:   b->spptr = NULL;

6886:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetUseScalableIncreaseOverlap_C", MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ));
6887:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatStoreValues_C", MatStoreValues_MPIAIJ));
6888:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatRetrieveValues_C", MatRetrieveValues_MPIAIJ));
6889:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatIsTranspose_C", MatIsTranspose_MPIAIJ));
6890:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocation_C", MatMPIAIJSetPreallocation_MPIAIJ));
6891:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetPreallocation_C", MatResetPreallocation_MPIAIJ));
6892:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocationCSR_C", MatMPIAIJSetPreallocationCSR_MPIAIJ));
6893:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatDiagonalScaleLocal_C", MatDiagonalScaleLocal_MPIAIJ));
6894:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijperm_C", MatConvert_MPIAIJ_MPIAIJPERM));
6895:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijsell_C", MatConvert_MPIAIJ_MPIAIJSELL));
6896: #if defined(PETSC_HAVE_CUDA)
6897:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcusparse_C", MatConvert_MPIAIJ_MPIAIJCUSPARSE));
6898: #endif
6899: #if defined(PETSC_HAVE_HIP)
6900:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijhipsparse_C", MatConvert_MPIAIJ_MPIAIJHIPSPARSE));
6901: #endif
6902: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6903:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijkokkos_C", MatConvert_MPIAIJ_MPIAIJKokkos));
6904: #endif
6905: #if defined(PETSC_HAVE_MKL_SPARSE)
6906:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijmkl_C", MatConvert_MPIAIJ_MPIAIJMKL));
6907: #endif
6908:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcrl_C", MatConvert_MPIAIJ_MPIAIJCRL));
6909:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpibaij_C", MatConvert_MPIAIJ_MPIBAIJ));
6910:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisbaij_C", MatConvert_MPIAIJ_MPISBAIJ));
6911:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpidense_C", MatConvert_MPIAIJ_MPIDense));
6912: #if defined(PETSC_HAVE_ELEMENTAL)
6913:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_elemental_C", MatConvert_MPIAIJ_Elemental));
6914: #endif
6915: #if defined(PETSC_HAVE_SCALAPACK)
6916:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_scalapack_C", MatConvert_AIJ_ScaLAPACK));
6917: #endif
6918:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_is_C", MatConvert_XAIJ_IS));
6919:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisell_C", MatConvert_MPIAIJ_MPISELL));
6920: #if defined(PETSC_HAVE_HYPRE)
6921:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_hypre_C", MatConvert_AIJ_HYPRE));
6922:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", MatProductSetFromOptions_Transpose_AIJ_AIJ));
6923: #endif
6924:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_is_mpiaij_C", MatProductSetFromOptions_IS_XAIJ));
6925:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_mpiaij_mpiaij_C", MatProductSetFromOptions_MPIAIJ));
6926:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_MPIAIJ));
6927:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetValuesCOO_C", MatSetValuesCOO_MPIAIJ));
6928:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATMPIAIJ));
6929:   PetscFunctionReturn(PETSC_SUCCESS);
6930: }

6932: /*@C
6933:   MatCreateMPIAIJWithSplitArrays - creates a `MATMPIAIJ` matrix using arrays that contain the "diagonal"
6934:   and "off-diagonal" part of the matrix in CSR format.

6936:   Collective

6938:   Input Parameters:
6939: + comm - MPI communicator
6940: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
6941: . n    - This value should be the same as the local size used in creating the
6942:          x vector for the matrix-vector product $y = Ax$. (or `PETSC_DECIDE` to have
6943:          calculated if `N` is given) For square matrices `n` is almost always `m`.
6944: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
6945: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
6946: . i    - row indices for "diagonal" portion of matrix; that is i[0] = 0, i[row] = i[row-1] + number of elements in that row of the matrix
6947: . j    - column indices, which must be local, i.e., based off the start column of the diagonal portion
6948: . a    - matrix values
6949: . oi   - row indices for "off-diagonal" portion of matrix; that is oi[0] = 0, oi[row] = oi[row-1] + number of elements in that row of the matrix
6950: . oj   - column indices, which must be global, representing global columns in the `MATMPIAIJ` matrix
6951: - oa   - matrix values

6953:   Output Parameter:
6954: . mat - the matrix

6956:   Level: advanced

6958:   Notes:
6959:   The `i`, `j`, and `a` arrays ARE NOT copied by this routine into the internal format used by PETSc (even in Fortran). The user
6960:   must free the arrays once the matrix has been destroyed and not before.

6962:   The `i` and `j` indices are 0 based

6964:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix

6966:   This sets local rows and cannot be used to set off-processor values.

6968:   Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
6969:   legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
6970:   not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
6971:   the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
6972:   keep track of the underlying array. Use `MatSetOption`(A,`MAT_NO_OFF_PROC_ENTRIES`,`PETSC_TRUE`) to disable all
6973:   communication if it is known that only local entries will be set.

6975: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
6976:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithArrays()`
6977: @*/
6978: PetscErrorCode MatCreateMPIAIJWithSplitArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, PetscInt i[], PetscInt j[], PetscScalar a[], PetscInt oi[], PetscInt oj[], PetscScalar oa[], Mat *mat)
6979: {
6980:   Mat_MPIAIJ *maij;

6982:   PetscFunctionBegin;
6983:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
6984:   PetscCheck(i[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
6985:   PetscCheck(oi[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "oi (row indices) must start with 0");
6986:   PetscCall(MatCreate(comm, mat));
6987:   PetscCall(MatSetSizes(*mat, m, n, M, N));
6988:   PetscCall(MatSetType(*mat, MATMPIAIJ));
6989:   maij = (Mat_MPIAIJ *)(*mat)->data;

6991:   (*mat)->preallocated = PETSC_TRUE;

6993:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
6994:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

6996:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, i, j, a, &maij->A));
6997:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, (*mat)->cmap->N, oi, oj, oa, &maij->B));

6999:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
7000:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
7001:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
7002:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
7003:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
7004:   PetscFunctionReturn(PETSC_SUCCESS);
7005: }

7007: typedef struct {
7008:   Mat       *mp;    /* intermediate products */
7009:   PetscBool *mptmp; /* is the intermediate product temporary ? */
7010:   PetscInt   cp;    /* number of intermediate products */

7012:   /* support for MatGetBrowsOfAoCols_MPIAIJ for P_oth */
7013:   PetscInt    *startsj_s, *startsj_r;
7014:   PetscScalar *bufa;
7015:   Mat          P_oth;

7017:   /* may take advantage of merging product->B */
7018:   Mat Bloc; /* B-local by merging diag and off-diag */

7020:   /* cusparse does not have support to split between symbolic and numeric phases.
7021:      When api_user is true, we don't need to update the numerical values
7022:      of the temporary storage */
7023:   PetscBool reusesym;

7025:   /* support for COO values insertion */
7026:   PetscScalar *coo_v, *coo_w; /* store on-process and off-process COO scalars, and used as MPI recv/send buffers respectively */
7027:   PetscInt   **own;           /* own[i] points to address of on-process COO indices for Mat mp[i] */
7028:   PetscInt   **off;           /* off[i] points to address of off-process COO indices for Mat mp[i] */
7029:   PetscBool    hasoffproc;    /* if true, have off-process values insertion (i.e. AtB or PtAP) */
7030:   PetscSF      sf;            /* used for non-local values insertion and memory malloc */
7031:   PetscMemType mtype;

7033:   /* customization */
7034:   PetscBool abmerge;
7035:   PetscBool P_oth_bind;
7036: } MatMatMPIAIJBACKEND;

7038: static PetscErrorCode MatDestroy_MatMatMPIAIJBACKEND(void *data)
7039: {
7040:   MatMatMPIAIJBACKEND *mmdata = (MatMatMPIAIJBACKEND *)data;
7041:   PetscInt             i;

7043:   PetscFunctionBegin;
7044:   PetscCall(PetscFree2(mmdata->startsj_s, mmdata->startsj_r));
7045:   PetscCall(PetscFree(mmdata->bufa));
7046:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_v));
7047:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_w));
7048:   PetscCall(MatDestroy(&mmdata->P_oth));
7049:   PetscCall(MatDestroy(&mmdata->Bloc));
7050:   PetscCall(PetscSFDestroy(&mmdata->sf));
7051:   for (i = 0; i < mmdata->cp; i++) PetscCall(MatDestroy(&mmdata->mp[i]));
7052:   PetscCall(PetscFree2(mmdata->mp, mmdata->mptmp));
7053:   PetscCall(PetscFree(mmdata->own[0]));
7054:   PetscCall(PetscFree(mmdata->own));
7055:   PetscCall(PetscFree(mmdata->off[0]));
7056:   PetscCall(PetscFree(mmdata->off));
7057:   PetscCall(PetscFree(mmdata));
7058:   PetscFunctionReturn(PETSC_SUCCESS);
7059: }

7061: /* Copy selected n entries with indices in idx[] of A to v[].
7062:    If idx is NULL, copy the whole data array of A to v[]
7063:  */
7064: static PetscErrorCode MatSeqAIJCopySubArray(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
7065: {
7066:   PetscErrorCode (*f)(Mat, PetscInt, const PetscInt[], PetscScalar[]);

7068:   PetscFunctionBegin;
7069:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", &f));
7070:   if (f) {
7071:     PetscCall((*f)(A, n, idx, v));
7072:   } else {
7073:     const PetscScalar *vv;

7075:     PetscCall(MatSeqAIJGetArrayRead(A, &vv));
7076:     if (n && idx) {
7077:       PetscScalar    *w  = v;
7078:       const PetscInt *oi = idx;
7079:       PetscInt        j;

7081:       for (j = 0; j < n; j++) *w++ = vv[*oi++];
7082:     } else {
7083:       PetscCall(PetscArraycpy(v, vv, n));
7084:     }
7085:     PetscCall(MatSeqAIJRestoreArrayRead(A, &vv));
7086:   }
7087:   PetscFunctionReturn(PETSC_SUCCESS);
7088: }

7090: static PetscErrorCode MatProductNumeric_MPIAIJBACKEND(Mat C)
7091: {
7092:   MatMatMPIAIJBACKEND *mmdata;
7093:   PetscInt             i, n_d, n_o;

7095:   PetscFunctionBegin;
7096:   MatCheckProduct(C, 1);
7097:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data empty");
7098:   mmdata = (MatMatMPIAIJBACKEND *)C->product->data;
7099:   if (!mmdata->reusesym) { /* update temporary matrices */
7100:     if (mmdata->P_oth) PetscCall(MatGetBrowsOfAoCols_MPIAIJ(C->product->A, C->product->B, MAT_REUSE_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7101:     if (mmdata->Bloc) PetscCall(MatMPIAIJGetLocalMatMerge(C->product->B, MAT_REUSE_MATRIX, NULL, &mmdata->Bloc));
7102:   }
7103:   mmdata->reusesym = PETSC_FALSE;

7105:   for (i = 0; i < mmdata->cp; i++) {
7106:     PetscCheck(mmdata->mp[i]->ops->productnumeric, PetscObjectComm((PetscObject)mmdata->mp[i]), PETSC_ERR_PLIB, "Missing numeric op for %s", MatProductTypes[mmdata->mp[i]->product->type]);
7107:     PetscCall((*mmdata->mp[i]->ops->productnumeric)(mmdata->mp[i]));
7108:   }
7109:   for (i = 0, n_d = 0, n_o = 0; i < mmdata->cp; i++) {
7110:     PetscInt noff = mmdata->off[i + 1] - mmdata->off[i];

7112:     if (mmdata->mptmp[i]) continue;
7113:     if (noff) {
7114:       PetscInt nown = mmdata->own[i + 1] - mmdata->own[i];

7116:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], noff, mmdata->off[i], mmdata->coo_w + n_o));
7117:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], nown, mmdata->own[i], mmdata->coo_v + n_d));
7118:       n_o += noff;
7119:       n_d += nown;
7120:     } else {
7121:       Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mmdata->mp[i]->data;

7123:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], mm->nz, NULL, mmdata->coo_v + n_d));
7124:       n_d += mm->nz;
7125:     }
7126:   }
7127:   if (mmdata->hasoffproc) { /* offprocess insertion */
7128:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7129:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7130:   }
7131:   PetscCall(MatSetValuesCOO(C, mmdata->coo_v, INSERT_VALUES));
7132:   PetscFunctionReturn(PETSC_SUCCESS);
7133: }

7135: /* Support for Pt * A, A * P, or Pt * A * P */
7136: #define MAX_NUMBER_INTERMEDIATE 4
7137: PetscErrorCode MatProductSymbolic_MPIAIJBACKEND(Mat C)
7138: {
7139:   Mat_Product           *product = C->product;
7140:   Mat                    A, P, mp[MAX_NUMBER_INTERMEDIATE]; /* A, P and a series of intermediate matrices */
7141:   Mat_MPIAIJ            *a, *p;
7142:   MatMatMPIAIJBACKEND   *mmdata;
7143:   ISLocalToGlobalMapping P_oth_l2g = NULL;
7144:   IS                     glob      = NULL;
7145:   const char            *prefix;
7146:   char                   pprefix[256];
7147:   const PetscInt        *globidx, *P_oth_idx;
7148:   PetscInt               i, j, cp, m, n, M, N, *coo_i, *coo_j;
7149:   PetscCount             ncoo, ncoo_d, ncoo_o, ncoo_oown;
7150:   PetscInt               cmapt[MAX_NUMBER_INTERMEDIATE], rmapt[MAX_NUMBER_INTERMEDIATE]; /* col/row map type for each Mat in mp[]. */
7151:                                                                                          /* type-0: consecutive, start from 0; type-1: consecutive with */
7152:                                                                                          /* a base offset; type-2: sparse with a local to global map table */
7153:   const PetscInt *cmapa[MAX_NUMBER_INTERMEDIATE], *rmapa[MAX_NUMBER_INTERMEDIATE];       /* col/row local to global map array (table) for type-2 map type */

7155:   MatProductType ptype;
7156:   PetscBool      mptmp[MAX_NUMBER_INTERMEDIATE], hasoffproc = PETSC_FALSE, iscuda, iship, iskokk;
7157:   PetscMPIInt    size;

7159:   PetscFunctionBegin;
7160:   MatCheckProduct(C, 1);
7161:   PetscCheck(!product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
7162:   ptype = product->type;
7163:   if (product->A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
7164:     ptype                                          = MATPRODUCT_AB;
7165:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
7166:   }
7167:   switch (ptype) {
7168:   case MATPRODUCT_AB:
7169:     A          = product->A;
7170:     P          = product->B;
7171:     m          = A->rmap->n;
7172:     n          = P->cmap->n;
7173:     M          = A->rmap->N;
7174:     N          = P->cmap->N;
7175:     hasoffproc = PETSC_FALSE; /* will not scatter mat product values to other processes */
7176:     break;
7177:   case MATPRODUCT_AtB:
7178:     P          = product->A;
7179:     A          = product->B;
7180:     m          = P->cmap->n;
7181:     n          = A->cmap->n;
7182:     M          = P->cmap->N;
7183:     N          = A->cmap->N;
7184:     hasoffproc = PETSC_TRUE;
7185:     break;
7186:   case MATPRODUCT_PtAP:
7187:     A          = product->A;
7188:     P          = product->B;
7189:     m          = P->cmap->n;
7190:     n          = P->cmap->n;
7191:     M          = P->cmap->N;
7192:     N          = P->cmap->N;
7193:     hasoffproc = PETSC_TRUE;
7194:     break;
7195:   default:
7196:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7197:   }
7198:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)C), &size));
7199:   if (size == 1) hasoffproc = PETSC_FALSE;

7201:   /* defaults */
7202:   for (i = 0; i < MAX_NUMBER_INTERMEDIATE; i++) {
7203:     mp[i]    = NULL;
7204:     mptmp[i] = PETSC_FALSE;
7205:     rmapt[i] = -1;
7206:     cmapt[i] = -1;
7207:     rmapa[i] = NULL;
7208:     cmapa[i] = NULL;
7209:   }

7211:   /* customization */
7212:   PetscCall(PetscNew(&mmdata));
7213:   mmdata->reusesym = product->api_user;
7214:   if (ptype == MATPRODUCT_AB) {
7215:     if (product->api_user) {
7216:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
7217:       PetscCall(PetscOptionsBool("-matmatmult_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7218:       PetscCall(PetscOptionsBool("-matmatmult_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7219:       PetscOptionsEnd();
7220:     } else {
7221:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
7222:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7223:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7224:       PetscOptionsEnd();
7225:     }
7226:   } else if (ptype == MATPRODUCT_PtAP) {
7227:     if (product->api_user) {
7228:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
7229:       PetscCall(PetscOptionsBool("-matptap_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7230:       PetscOptionsEnd();
7231:     } else {
7232:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
7233:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7234:       PetscOptionsEnd();
7235:     }
7236:   }
7237:   a = (Mat_MPIAIJ *)A->data;
7238:   p = (Mat_MPIAIJ *)P->data;
7239:   PetscCall(MatSetSizes(C, m, n, M, N));
7240:   PetscCall(PetscLayoutSetUp(C->rmap));
7241:   PetscCall(PetscLayoutSetUp(C->cmap));
7242:   PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
7243:   PetscCall(MatGetOptionsPrefix(C, &prefix));

7245:   cp = 0;
7246:   switch (ptype) {
7247:   case MATPRODUCT_AB: /* A * P */
7248:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));

7250:     /* A_diag * P_local (merged or not) */
7251:     if (mmdata->abmerge) { /* P's diagonal and off-diag blocks are merged to one matrix, then multiplied by A_diag */
7252:       /* P is product->B */
7253:       PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7254:       PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7255:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7256:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7257:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7258:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7259:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7260:       mp[cp]->product->api_user = product->api_user;
7261:       PetscCall(MatProductSetFromOptions(mp[cp]));
7262:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7263:       PetscCall(ISGetIndices(glob, &globidx));
7264:       rmapt[cp] = 1;
7265:       cmapt[cp] = 2;
7266:       cmapa[cp] = globidx;
7267:       mptmp[cp] = PETSC_FALSE;
7268:       cp++;
7269:     } else { /* A_diag * P_diag and A_diag * P_off */
7270:       PetscCall(MatProductCreate(a->A, p->A, NULL, &mp[cp]));
7271:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7272:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7273:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7274:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7275:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7276:       mp[cp]->product->api_user = product->api_user;
7277:       PetscCall(MatProductSetFromOptions(mp[cp]));
7278:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7279:       rmapt[cp] = 1;
7280:       cmapt[cp] = 1;
7281:       mptmp[cp] = PETSC_FALSE;
7282:       cp++;
7283:       PetscCall(MatProductCreate(a->A, p->B, NULL, &mp[cp]));
7284:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7285:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7286:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7287:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7288:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7289:       mp[cp]->product->api_user = product->api_user;
7290:       PetscCall(MatProductSetFromOptions(mp[cp]));
7291:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7292:       rmapt[cp] = 1;
7293:       cmapt[cp] = 2;
7294:       cmapa[cp] = p->garray;
7295:       mptmp[cp] = PETSC_FALSE;
7296:       cp++;
7297:     }

7299:     /* A_off * P_other */
7300:     if (mmdata->P_oth) {
7301:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g)); /* make P_oth use local col ids */
7302:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7303:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7304:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7305:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7306:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7307:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7308:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7309:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7310:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7311:       mp[cp]->product->api_user = product->api_user;
7312:       PetscCall(MatProductSetFromOptions(mp[cp]));
7313:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7314:       rmapt[cp] = 1;
7315:       cmapt[cp] = 2;
7316:       cmapa[cp] = P_oth_idx;
7317:       mptmp[cp] = PETSC_FALSE;
7318:       cp++;
7319:     }
7320:     break;

7322:   case MATPRODUCT_AtB: /* (P^t * A): P_diag * A_loc + P_off * A_loc */
7323:     /* A is product->B */
7324:     PetscCall(MatMPIAIJGetLocalMatMerge(A, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7325:     if (A == P) { /* when A==P, we can take advantage of the already merged mmdata->Bloc */
7326:       PetscCall(MatProductCreate(mmdata->Bloc, mmdata->Bloc, NULL, &mp[cp]));
7327:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7328:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7329:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7330:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7331:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7332:       mp[cp]->product->api_user = product->api_user;
7333:       PetscCall(MatProductSetFromOptions(mp[cp]));
7334:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7335:       PetscCall(ISGetIndices(glob, &globidx));
7336:       rmapt[cp] = 2;
7337:       rmapa[cp] = globidx;
7338:       cmapt[cp] = 2;
7339:       cmapa[cp] = globidx;
7340:       mptmp[cp] = PETSC_FALSE;
7341:       cp++;
7342:     } else {
7343:       PetscCall(MatProductCreate(p->A, mmdata->Bloc, NULL, &mp[cp]));
7344:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7345:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7346:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7347:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7348:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7349:       mp[cp]->product->api_user = product->api_user;
7350:       PetscCall(MatProductSetFromOptions(mp[cp]));
7351:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7352:       PetscCall(ISGetIndices(glob, &globidx));
7353:       rmapt[cp] = 1;
7354:       cmapt[cp] = 2;
7355:       cmapa[cp] = globidx;
7356:       mptmp[cp] = PETSC_FALSE;
7357:       cp++;
7358:       PetscCall(MatProductCreate(p->B, mmdata->Bloc, NULL, &mp[cp]));
7359:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7360:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7361:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7362:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7363:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7364:       mp[cp]->product->api_user = product->api_user;
7365:       PetscCall(MatProductSetFromOptions(mp[cp]));
7366:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7367:       rmapt[cp] = 2;
7368:       rmapa[cp] = p->garray;
7369:       cmapt[cp] = 2;
7370:       cmapa[cp] = globidx;
7371:       mptmp[cp] = PETSC_FALSE;
7372:       cp++;
7373:     }
7374:     break;
7375:   case MATPRODUCT_PtAP:
7376:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7377:     /* P is product->B */
7378:     PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7379:     PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7380:     PetscCall(MatProductSetType(mp[cp], MATPRODUCT_PtAP));
7381:     PetscCall(MatProductSetFill(mp[cp], product->fill));
7382:     PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7383:     PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7384:     PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7385:     mp[cp]->product->api_user = product->api_user;
7386:     PetscCall(MatProductSetFromOptions(mp[cp]));
7387:     PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7388:     PetscCall(ISGetIndices(glob, &globidx));
7389:     rmapt[cp] = 2;
7390:     rmapa[cp] = globidx;
7391:     cmapt[cp] = 2;
7392:     cmapa[cp] = globidx;
7393:     mptmp[cp] = PETSC_FALSE;
7394:     cp++;
7395:     if (mmdata->P_oth) {
7396:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g));
7397:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7398:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7399:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7400:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7401:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7402:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7403:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7404:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7405:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7406:       mp[cp]->product->api_user = product->api_user;
7407:       PetscCall(MatProductSetFromOptions(mp[cp]));
7408:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7409:       mptmp[cp] = PETSC_TRUE;
7410:       cp++;
7411:       PetscCall(MatProductCreate(mmdata->Bloc, mp[1], NULL, &mp[cp]));
7412:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7413:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7414:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7415:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7416:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7417:       mp[cp]->product->api_user = product->api_user;
7418:       PetscCall(MatProductSetFromOptions(mp[cp]));
7419:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7420:       rmapt[cp] = 2;
7421:       rmapa[cp] = globidx;
7422:       cmapt[cp] = 2;
7423:       cmapa[cp] = P_oth_idx;
7424:       mptmp[cp] = PETSC_FALSE;
7425:       cp++;
7426:     }
7427:     break;
7428:   default:
7429:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7430:   }
7431:   /* sanity check */
7432:   if (size > 1)
7433:     for (i = 0; i < cp; i++) PetscCheck(rmapt[i] != 2 || hasoffproc, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Unexpected offproc map type for product %" PetscInt_FMT, i);

7435:   PetscCall(PetscMalloc2(cp, &mmdata->mp, cp, &mmdata->mptmp));
7436:   for (i = 0; i < cp; i++) {
7437:     mmdata->mp[i]    = mp[i];
7438:     mmdata->mptmp[i] = mptmp[i];
7439:   }
7440:   mmdata->cp             = cp;
7441:   C->product->data       = mmdata;
7442:   C->product->destroy    = MatDestroy_MatMatMPIAIJBACKEND;
7443:   C->ops->productnumeric = MatProductNumeric_MPIAIJBACKEND;

7445:   /* memory type */
7446:   mmdata->mtype = PETSC_MEMTYPE_HOST;
7447:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iscuda, MATSEQAIJCUSPARSE, MATMPIAIJCUSPARSE, ""));
7448:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iship, MATSEQAIJHIPSPARSE, MATMPIAIJHIPSPARSE, ""));
7449:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iskokk, MATSEQAIJKOKKOS, MATMPIAIJKOKKOS, ""));
7450:   if (iscuda) mmdata->mtype = PETSC_MEMTYPE_CUDA;
7451:   else if (iship) mmdata->mtype = PETSC_MEMTYPE_HIP;
7452:   else if (iskokk) mmdata->mtype = PETSC_MEMTYPE_KOKKOS;

7454:   /* prepare coo coordinates for values insertion */

7456:   /* count total nonzeros of those intermediate seqaij Mats
7457:     ncoo_d:    # of nonzeros of matrices that do not have offproc entries
7458:     ncoo_o:    # of nonzeros (of matrices that might have offproc entries) that will be inserted to remote procs
7459:     ncoo_oown: # of nonzeros (of matrices that might have offproc entries) that will be inserted locally
7460:   */
7461:   for (cp = 0, ncoo_d = 0, ncoo_o = 0, ncoo_oown = 0; cp < mmdata->cp; cp++) {
7462:     Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mp[cp]->data;
7463:     if (mptmp[cp]) continue;
7464:     if (rmapt[cp] == 2 && hasoffproc) { /* the rows need to be scatter to all processes (might include self) */
7465:       const PetscInt *rmap = rmapa[cp];
7466:       const PetscInt  mr   = mp[cp]->rmap->n;
7467:       const PetscInt  rs   = C->rmap->rstart;
7468:       const PetscInt  re   = C->rmap->rend;
7469:       const PetscInt *ii   = mm->i;
7470:       for (i = 0; i < mr; i++) {
7471:         const PetscInt gr = rmap[i];
7472:         const PetscInt nz = ii[i + 1] - ii[i];
7473:         if (gr < rs || gr >= re) ncoo_o += nz; /* this row is offproc */
7474:         else ncoo_oown += nz;                  /* this row is local */
7475:       }
7476:     } else ncoo_d += mm->nz;
7477:   }

7479:   /*
7480:     ncoo: total number of nonzeros (including those inserted by remote procs) belonging to this proc

7482:     ncoo = ncoo_d + ncoo_oown + ncoo2, which ncoo2 is number of nonzeros inserted to me by other procs.

7484:     off[0] points to a big index array, which is shared by off[1,2,...]. Similarly, for own[0].

7486:     off[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert to others
7487:     own[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert locally
7488:     so, off[p+1]-off[p] is the number of nonzeros that mp[p] will send to others.

7490:     coo_i/j/v[]: [ncoo] row/col/val of nonzeros belonging to this proc.
7491:     Ex. coo_i[]: the beginning part (of size ncoo_d + ncoo_oown) stores i of local nonzeros, and the remaining part stores i of nonzeros I will receive.
7492:   */
7493:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->off)); /* +1 to make a csr-like data structure */
7494:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->own));

7496:   /* gather (i,j) of nonzeros inserted by remote procs */
7497:   if (hasoffproc) {
7498:     PetscSF  msf;
7499:     PetscInt ncoo2, *coo_i2, *coo_j2;

7501:     PetscCall(PetscMalloc1(ncoo_o, &mmdata->off[0]));
7502:     PetscCall(PetscMalloc1(ncoo_oown, &mmdata->own[0]));
7503:     PetscCall(PetscMalloc2(ncoo_o, &coo_i, ncoo_o, &coo_j)); /* to collect (i,j) of entries to be sent to others */

7505:     for (cp = 0, ncoo_o = 0; cp < mmdata->cp; cp++) {
7506:       Mat_SeqAIJ *mm     = (Mat_SeqAIJ *)mp[cp]->data;
7507:       PetscInt   *idxoff = mmdata->off[cp];
7508:       PetscInt   *idxown = mmdata->own[cp];
7509:       if (!mptmp[cp] && rmapt[cp] == 2) { /* row map is sparse */
7510:         const PetscInt *rmap = rmapa[cp];
7511:         const PetscInt *cmap = cmapa[cp];
7512:         const PetscInt *ii   = mm->i;
7513:         PetscInt       *coi  = coo_i + ncoo_o;
7514:         PetscInt       *coj  = coo_j + ncoo_o;
7515:         const PetscInt  mr   = mp[cp]->rmap->n;
7516:         const PetscInt  rs   = C->rmap->rstart;
7517:         const PetscInt  re   = C->rmap->rend;
7518:         const PetscInt  cs   = C->cmap->rstart;
7519:         for (i = 0; i < mr; i++) {
7520:           const PetscInt *jj = mm->j + ii[i];
7521:           const PetscInt  gr = rmap[i];
7522:           const PetscInt  nz = ii[i + 1] - ii[i];
7523:           if (gr < rs || gr >= re) { /* this is an offproc row */
7524:             for (j = ii[i]; j < ii[i + 1]; j++) {
7525:               *coi++    = gr;
7526:               *idxoff++ = j;
7527:             }
7528:             if (!cmapt[cp]) { /* already global */
7529:               for (j = 0; j < nz; j++) *coj++ = jj[j];
7530:             } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7531:               for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7532:             } else { /* offdiag */
7533:               for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7534:             }
7535:             ncoo_o += nz;
7536:           } else { /* this is a local row */
7537:             for (j = ii[i]; j < ii[i + 1]; j++) *idxown++ = j;
7538:           }
7539:         }
7540:       }
7541:       mmdata->off[cp + 1] = idxoff;
7542:       mmdata->own[cp + 1] = idxown;
7543:     }

7545:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7546:     PetscCall(PetscSFSetGraphLayout(mmdata->sf, C->rmap, ncoo_o /*nleaves*/, NULL /*ilocal*/, PETSC_OWN_POINTER, coo_i));
7547:     PetscCall(PetscSFGetMultiSF(mmdata->sf, &msf));
7548:     PetscCall(PetscSFGetGraph(msf, &ncoo2 /*nroots*/, NULL, NULL, NULL));
7549:     ncoo = ncoo_d + ncoo_oown + ncoo2;
7550:     PetscCall(PetscMalloc2(ncoo, &coo_i2, ncoo, &coo_j2));
7551:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown)); /* put (i,j) of remote nonzeros at back */
7552:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown));
7553:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7554:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7555:     PetscCall(PetscFree2(coo_i, coo_j));
7556:     /* allocate MPI send buffer to collect nonzero values to be sent to remote procs */
7557:     PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo_o * sizeof(PetscScalar), (void **)&mmdata->coo_w));
7558:     coo_i = coo_i2;
7559:     coo_j = coo_j2;
7560:   } else { /* no offproc values insertion */
7561:     ncoo = ncoo_d;
7562:     PetscCall(PetscMalloc2(ncoo, &coo_i, ncoo, &coo_j));

7564:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7565:     PetscCall(PetscSFSetGraph(mmdata->sf, 0, 0, NULL, PETSC_OWN_POINTER, NULL, PETSC_OWN_POINTER));
7566:     PetscCall(PetscSFSetUp(mmdata->sf));
7567:   }
7568:   mmdata->hasoffproc = hasoffproc;

7570:   /* gather (i,j) of nonzeros inserted locally */
7571:   for (cp = 0, ncoo_d = 0; cp < mmdata->cp; cp++) {
7572:     Mat_SeqAIJ     *mm   = (Mat_SeqAIJ *)mp[cp]->data;
7573:     PetscInt       *coi  = coo_i + ncoo_d;
7574:     PetscInt       *coj  = coo_j + ncoo_d;
7575:     const PetscInt *jj   = mm->j;
7576:     const PetscInt *ii   = mm->i;
7577:     const PetscInt *cmap = cmapa[cp];
7578:     const PetscInt *rmap = rmapa[cp];
7579:     const PetscInt  mr   = mp[cp]->rmap->n;
7580:     const PetscInt  rs   = C->rmap->rstart;
7581:     const PetscInt  re   = C->rmap->rend;
7582:     const PetscInt  cs   = C->cmap->rstart;

7584:     if (mptmp[cp]) continue;
7585:     if (rmapt[cp] == 1) { /* consecutive rows */
7586:       /* fill coo_i */
7587:       for (i = 0; i < mr; i++) {
7588:         const PetscInt gr = i + rs;
7589:         for (j = ii[i]; j < ii[i + 1]; j++) coi[j] = gr;
7590:       }
7591:       /* fill coo_j */
7592:       if (!cmapt[cp]) { /* type-0, already global */
7593:         PetscCall(PetscArraycpy(coj, jj, mm->nz));
7594:       } else if (cmapt[cp] == 1) {                        /* type-1, local to global for consecutive columns of C */
7595:         for (j = 0; j < mm->nz; j++) coj[j] = jj[j] + cs; /* lid + col start */
7596:       } else {                                            /* type-2, local to global for sparse columns */
7597:         for (j = 0; j < mm->nz; j++) coj[j] = cmap[jj[j]];
7598:       }
7599:       ncoo_d += mm->nz;
7600:     } else if (rmapt[cp] == 2) { /* sparse rows */
7601:       for (i = 0; i < mr; i++) {
7602:         const PetscInt *jj = mm->j + ii[i];
7603:         const PetscInt  gr = rmap[i];
7604:         const PetscInt  nz = ii[i + 1] - ii[i];
7605:         if (gr >= rs && gr < re) { /* local rows */
7606:           for (j = ii[i]; j < ii[i + 1]; j++) *coi++ = gr;
7607:           if (!cmapt[cp]) { /* type-0, already global */
7608:             for (j = 0; j < nz; j++) *coj++ = jj[j];
7609:           } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7610:             for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7611:           } else { /* type-2, local to global for sparse columns */
7612:             for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7613:           }
7614:           ncoo_d += nz;
7615:         }
7616:       }
7617:     }
7618:   }
7619:   if (glob) PetscCall(ISRestoreIndices(glob, &globidx));
7620:   PetscCall(ISDestroy(&glob));
7621:   if (P_oth_l2g) PetscCall(ISLocalToGlobalMappingRestoreIndices(P_oth_l2g, &P_oth_idx));
7622:   PetscCall(ISLocalToGlobalMappingDestroy(&P_oth_l2g));
7623:   /* allocate an array to store all nonzeros (inserted locally or remotely) belonging to this proc */
7624:   PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo * sizeof(PetscScalar), (void **)&mmdata->coo_v));

7626:   /* preallocate with COO data */
7627:   PetscCall(MatSetPreallocationCOO(C, ncoo, coo_i, coo_j));
7628:   PetscCall(PetscFree2(coo_i, coo_j));
7629:   PetscFunctionReturn(PETSC_SUCCESS);
7630: }

7632: PetscErrorCode MatProductSetFromOptions_MPIAIJBACKEND(Mat mat)
7633: {
7634:   Mat_Product *product = mat->product;
7635: #if defined(PETSC_HAVE_DEVICE)
7636:   PetscBool match  = PETSC_FALSE;
7637:   PetscBool usecpu = PETSC_FALSE;
7638: #else
7639:   PetscBool match = PETSC_TRUE;
7640: #endif

7642:   PetscFunctionBegin;
7643:   MatCheckProduct(mat, 1);
7644: #if defined(PETSC_HAVE_DEVICE)
7645:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, ((PetscObject)product->A)->type_name, &match));
7646:   if (match) { /* we can always fallback to the CPU if requested */
7647:     switch (product->type) {
7648:     case MATPRODUCT_AB:
7649:       if (product->api_user) {
7650:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
7651:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7652:         PetscOptionsEnd();
7653:       } else {
7654:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
7655:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7656:         PetscOptionsEnd();
7657:       }
7658:       break;
7659:     case MATPRODUCT_AtB:
7660:       if (product->api_user) {
7661:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
7662:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7663:         PetscOptionsEnd();
7664:       } else {
7665:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
7666:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7667:         PetscOptionsEnd();
7668:       }
7669:       break;
7670:     case MATPRODUCT_PtAP:
7671:       if (product->api_user) {
7672:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
7673:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7674:         PetscOptionsEnd();
7675:       } else {
7676:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
7677:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7678:         PetscOptionsEnd();
7679:       }
7680:       break;
7681:     default:
7682:       break;
7683:     }
7684:     match = (PetscBool)!usecpu;
7685:   }
7686: #endif
7687:   if (match) {
7688:     switch (product->type) {
7689:     case MATPRODUCT_AB:
7690:     case MATPRODUCT_AtB:
7691:     case MATPRODUCT_PtAP:
7692:       mat->ops->productsymbolic = MatProductSymbolic_MPIAIJBACKEND;
7693:       break;
7694:     default:
7695:       break;
7696:     }
7697:   }
7698:   /* fallback to MPIAIJ ops */
7699:   if (!mat->ops->productsymbolic) PetscCall(MatProductSetFromOptions_MPIAIJ(mat));
7700:   PetscFunctionReturn(PETSC_SUCCESS);
7701: }

7703: /*
7704:    Produces a set of block column indices of the matrix row, one for each block represented in the original row

7706:    n - the number of block indices in cc[]
7707:    cc - the block indices (must be large enough to contain the indices)
7708: */
7709: static inline PetscErrorCode MatCollapseRow(Mat Amat, PetscInt row, PetscInt bs, PetscInt *n, PetscInt *cc)
7710: {
7711:   PetscInt        cnt = -1, nidx, j;
7712:   const PetscInt *idx;

7714:   PetscFunctionBegin;
7715:   PetscCall(MatGetRow(Amat, row, &nidx, &idx, NULL));
7716:   if (nidx) {
7717:     cnt     = 0;
7718:     cc[cnt] = idx[0] / bs;
7719:     for (j = 1; j < nidx; j++) {
7720:       if (cc[cnt] < idx[j] / bs) cc[++cnt] = idx[j] / bs;
7721:     }
7722:   }
7723:   PetscCall(MatRestoreRow(Amat, row, &nidx, &idx, NULL));
7724:   *n = cnt + 1;
7725:   PetscFunctionReturn(PETSC_SUCCESS);
7726: }

7728: /*
7729:     Produces a set of block column indices of the matrix block row, one for each block represented in the original set of rows

7731:     ncollapsed - the number of block indices
7732:     collapsed - the block indices (must be large enough to contain the indices)
7733: */
7734: static inline PetscErrorCode MatCollapseRows(Mat Amat, PetscInt start, PetscInt bs, PetscInt *w0, PetscInt *w1, PetscInt *w2, PetscInt *ncollapsed, PetscInt **collapsed)
7735: {
7736:   PetscInt i, nprev, *cprev = w0, ncur = 0, *ccur = w1, *merged = w2, *cprevtmp;

7738:   PetscFunctionBegin;
7739:   PetscCall(MatCollapseRow(Amat, start, bs, &nprev, cprev));
7740:   for (i = start + 1; i < start + bs; i++) {
7741:     PetscCall(MatCollapseRow(Amat, i, bs, &ncur, ccur));
7742:     PetscCall(PetscMergeIntArray(nprev, cprev, ncur, ccur, &nprev, &merged));
7743:     cprevtmp = cprev;
7744:     cprev    = merged;
7745:     merged   = cprevtmp;
7746:   }
7747:   *ncollapsed = nprev;
7748:   if (collapsed) *collapsed = cprev;
7749:   PetscFunctionReturn(PETSC_SUCCESS);
7750: }

7752: /*
7753:  MatCreateGraph_Simple_AIJ - create simple scalar matrix (graph) from potentially blocked matrix

7755:  Input Parameter:
7756:  . Amat - matrix
7757:  - symmetrize - make the result symmetric
7758:  + scale - scale with diagonal

7760:  Output Parameter:
7761:  . a_Gmat - output scalar graph >= 0

7763: */
7764: PETSC_INTERN PetscErrorCode MatCreateGraph_Simple_AIJ(Mat Amat, PetscBool symmetrize, PetscBool scale, PetscReal filter, PetscInt index_size, PetscInt index[], Mat *a_Gmat)
7765: {
7766:   PetscInt  Istart, Iend, Ii, jj, kk, ncols, nloc, NN, MM, bs;
7767:   MPI_Comm  comm;
7768:   Mat       Gmat;
7769:   PetscBool ismpiaij, isseqaij;
7770:   Mat       a, b, c;
7771:   MatType   jtype;

7773:   PetscFunctionBegin;
7774:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
7775:   PetscCall(MatGetOwnershipRange(Amat, &Istart, &Iend));
7776:   PetscCall(MatGetSize(Amat, &MM, &NN));
7777:   PetscCall(MatGetBlockSize(Amat, &bs));
7778:   nloc = (Iend - Istart) / bs;

7780:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATSEQAIJ, &isseqaij));
7781:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATMPIAIJ, &ismpiaij));
7782:   PetscCheck(isseqaij || ismpiaij, comm, PETSC_ERR_USER, "Require (MPI)AIJ matrix type");

7784:   /* TODO GPU: these calls are potentially expensive if matrices are large and we want to use the GPU */
7785:   /* A solution consists in providing a new API, MatAIJGetCollapsedAIJ, and each class can provide a fast
7786:      implementation */
7787:   if (bs > 1) {
7788:     PetscCall(MatGetType(Amat, &jtype));
7789:     PetscCall(MatCreate(comm, &Gmat));
7790:     PetscCall(MatSetType(Gmat, jtype));
7791:     PetscCall(MatSetSizes(Gmat, nloc, nloc, PETSC_DETERMINE, PETSC_DETERMINE));
7792:     PetscCall(MatSetBlockSizes(Gmat, 1, 1));
7793:     if (isseqaij || ((Mat_MPIAIJ *)Amat->data)->garray) {
7794:       PetscInt  *d_nnz, *o_nnz;
7795:       MatScalar *aa, val, *AA;
7796:       PetscInt  *aj, *ai, *AJ, nc, nmax = 0;
7797:       if (isseqaij) {
7798:         a = Amat;
7799:         b = NULL;
7800:       } else {
7801:         Mat_MPIAIJ *d = (Mat_MPIAIJ *)Amat->data;
7802:         a             = d->A;
7803:         b             = d->B;
7804:       }
7805:       PetscCall(PetscInfo(Amat, "New bs>1 Graph. nloc=%" PetscInt_FMT "\n", nloc));
7806:       PetscCall(PetscMalloc2(nloc, &d_nnz, isseqaij ? 0 : nloc, &o_nnz));
7807:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7808:         PetscInt       *nnz = (c == a) ? d_nnz : o_nnz;
7809:         const PetscInt *cols1, *cols2;
7810:         for (PetscInt brow = 0, nc1, nc2, ok = 1; brow < nloc * bs; brow += bs) { // block rows
7811:           PetscCall(MatGetRow(c, brow, &nc2, &cols2, NULL));
7812:           nnz[brow / bs] = nc2 / bs;
7813:           if (nc2 % bs) ok = 0;
7814:           if (nnz[brow / bs] > nmax) nmax = nnz[brow / bs];
7815:           for (PetscInt ii = 1; ii < bs; ii++) { // check for non-dense blocks
7816:             PetscCall(MatGetRow(c, brow + ii, &nc1, &cols1, NULL));
7817:             if (nc1 != nc2) ok = 0;
7818:             else {
7819:               for (PetscInt jj = 0; jj < nc1 && ok == 1; jj++) {
7820:                 if (cols1[jj] != cols2[jj]) ok = 0;
7821:                 if (cols1[jj] % bs != jj % bs) ok = 0;
7822:               }
7823:             }
7824:             PetscCall(MatRestoreRow(c, brow + ii, &nc1, &cols1, NULL));
7825:           }
7826:           PetscCall(MatRestoreRow(c, brow, &nc2, &cols2, NULL));
7827:           if (!ok) {
7828:             PetscCall(PetscFree2(d_nnz, o_nnz));
7829:             PetscCall(PetscInfo(Amat, "Found sparse blocks - revert to slow method\n"));
7830:             goto old_bs;
7831:           }
7832:         }
7833:       }
7834:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7835:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7836:       PetscCall(PetscFree2(d_nnz, o_nnz));
7837:       PetscCall(PetscMalloc2(nmax, &AA, nmax, &AJ));
7838:       // diag
7839:       for (PetscInt brow = 0, n, grow; brow < nloc * bs; brow += bs) { // block rows
7840:         Mat_SeqAIJ *aseq = (Mat_SeqAIJ *)a->data;
7841:         ai               = aseq->i;
7842:         n                = ai[brow + 1] - ai[brow];
7843:         aj               = aseq->j + ai[brow];
7844:         for (int k = 0; k < n; k += bs) {        // block columns
7845:           AJ[k / bs] = aj[k] / bs + Istart / bs; // diag starts at (Istart,Istart)
7846:           val        = 0;
7847:           if (index_size == 0) {
7848:             for (int ii = 0; ii < bs; ii++) { // rows in block
7849:               aa = aseq->a + ai[brow + ii] + k;
7850:               for (int jj = 0; jj < bs; jj++) {         // columns in block
7851:                 val += PetscAbs(PetscRealPart(aa[jj])); // a sort of norm
7852:               }
7853:             }
7854:           } else {                                       // use (index,index) value if provided
7855:             for (int iii = 0; iii < index_size; iii++) { // rows in block
7856:               int ii = index[iii];
7857:               aa     = aseq->a + ai[brow + ii] + k;
7858:               for (int jjj = 0; jjj < index_size; jjj++) { // columns in block
7859:                 int jj = index[jjj];
7860:                 val += PetscAbs(PetscRealPart(aa[jj]));
7861:               }
7862:             }
7863:           }
7864:           PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%d) >= nmax (%d)", (int)(k / bs), (int)nmax);
7865:           AA[k / bs] = val;
7866:         }
7867:         grow = Istart / bs + brow / bs;
7868:         PetscCall(MatSetValues(Gmat, 1, &grow, n / bs, AJ, AA, ADD_VALUES));
7869:       }
7870:       // off-diag
7871:       if (ismpiaij) {
7872:         Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)Amat->data;
7873:         const PetscScalar *vals;
7874:         const PetscInt    *cols, *garray = aij->garray;
7875:         PetscCheck(garray, PETSC_COMM_SELF, PETSC_ERR_USER, "No garray ?");
7876:         for (PetscInt brow = 0, grow; brow < nloc * bs; brow += bs) { // block rows
7877:           PetscCall(MatGetRow(b, brow, &ncols, &cols, NULL));
7878:           for (int k = 0, cidx = 0; k < ncols; k += bs, cidx++) {
7879:             PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs >= nmax");
7880:             AA[k / bs] = 0;
7881:             AJ[cidx]   = garray[cols[k]] / bs;
7882:           }
7883:           nc = ncols / bs;
7884:           PetscCall(MatRestoreRow(b, brow, &ncols, &cols, NULL));
7885:           if (index_size == 0) {
7886:             for (int ii = 0; ii < bs; ii++) { // rows in block
7887:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7888:               for (int k = 0; k < ncols; k += bs) {
7889:                 for (int jj = 0; jj < bs; jj++) { // cols in block
7890:                   PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%d) >= nmax (%d)", (int)(k / bs), (int)nmax);
7891:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7892:                 }
7893:               }
7894:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7895:             }
7896:           } else {                                       // use (index,index) value if provided
7897:             for (int iii = 0; iii < index_size; iii++) { // rows in block
7898:               int ii = index[iii];
7899:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7900:               for (int k = 0; k < ncols; k += bs) {
7901:                 for (int jjj = 0; jjj < index_size; jjj++) { // cols in block
7902:                   int jj = index[jjj];
7903:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7904:                 }
7905:               }
7906:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7907:             }
7908:           }
7909:           grow = Istart / bs + brow / bs;
7910:           PetscCall(MatSetValues(Gmat, 1, &grow, nc, AJ, AA, ADD_VALUES));
7911:         }
7912:       }
7913:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7914:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7915:       PetscCall(PetscFree2(AA, AJ));
7916:     } else {
7917:       const PetscScalar *vals;
7918:       const PetscInt    *idx;
7919:       PetscInt          *d_nnz, *o_nnz, *w0, *w1, *w2;
7920:     old_bs:
7921:       /*
7922:        Determine the preallocation needed for the scalar matrix derived from the vector matrix.
7923:        */
7924:       PetscCall(PetscInfo(Amat, "OLD bs>1 CreateGraph\n"));
7925:       PetscCall(PetscMalloc2(nloc, &d_nnz, isseqaij ? 0 : nloc, &o_nnz));
7926:       if (isseqaij) {
7927:         PetscInt max_d_nnz;
7928:         /*
7929:          Determine exact preallocation count for (sequential) scalar matrix
7930:          */
7931:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Amat, &max_d_nnz));
7932:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7933:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7934:         for (Ii = 0, jj = 0; Ii < Iend; Ii += bs, jj++) PetscCall(MatCollapseRows(Amat, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7935:         PetscCall(PetscFree3(w0, w1, w2));
7936:       } else if (ismpiaij) {
7937:         Mat             Daij, Oaij;
7938:         const PetscInt *garray;
7939:         PetscInt        max_d_nnz;
7940:         PetscCall(MatMPIAIJGetSeqAIJ(Amat, &Daij, &Oaij, &garray));
7941:         /*
7942:          Determine exact preallocation count for diagonal block portion of scalar matrix
7943:          */
7944:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Daij, &max_d_nnz));
7945:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7946:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7947:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) PetscCall(MatCollapseRows(Daij, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7948:         PetscCall(PetscFree3(w0, w1, w2));
7949:         /*
7950:          Over estimate (usually grossly over), preallocation count for off-diagonal portion of scalar matrix
7951:          */
7952:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) {
7953:           o_nnz[jj] = 0;
7954:           for (kk = 0; kk < bs; kk++) { /* rows that get collapsed to a single row */
7955:             PetscCall(MatGetRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7956:             o_nnz[jj] += ncols;
7957:             PetscCall(MatRestoreRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7958:           }
7959:           if (o_nnz[jj] > (NN / bs - nloc)) o_nnz[jj] = NN / bs - nloc;
7960:         }
7961:       } else SETERRQ(comm, PETSC_ERR_USER, "Require AIJ matrix type");
7962:       /* get scalar copy (norms) of matrix */
7963:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7964:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7965:       PetscCall(PetscFree2(d_nnz, o_nnz));
7966:       for (Ii = Istart; Ii < Iend; Ii++) {
7967:         PetscInt dest_row = Ii / bs;
7968:         PetscCall(MatGetRow(Amat, Ii, &ncols, &idx, &vals));
7969:         for (jj = 0; jj < ncols; jj++) {
7970:           PetscInt    dest_col = idx[jj] / bs;
7971:           PetscScalar sv       = PetscAbs(PetscRealPart(vals[jj]));
7972:           PetscCall(MatSetValues(Gmat, 1, &dest_row, 1, &dest_col, &sv, ADD_VALUES));
7973:         }
7974:         PetscCall(MatRestoreRow(Amat, Ii, &ncols, &idx, &vals));
7975:       }
7976:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7977:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7978:     }
7979:   } else {
7980:     if (symmetrize || filter >= 0 || scale) PetscCall(MatDuplicate(Amat, MAT_COPY_VALUES, &Gmat));
7981:     else {
7982:       Gmat = Amat;
7983:       PetscCall(PetscObjectReference((PetscObject)Gmat));
7984:     }
7985:     if (isseqaij) {
7986:       a = Gmat;
7987:       b = NULL;
7988:     } else {
7989:       Mat_MPIAIJ *d = (Mat_MPIAIJ *)Gmat->data;
7990:       a             = d->A;
7991:       b             = d->B;
7992:     }
7993:     if (filter >= 0 || scale) {
7994:       /* take absolute value of each entry */
7995:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7996:         MatInfo      info;
7997:         PetscScalar *avals;
7998:         PetscCall(MatGetInfo(c, MAT_LOCAL, &info));
7999:         PetscCall(MatSeqAIJGetArray(c, &avals));
8000:         for (int jj = 0; jj < info.nz_used; jj++) avals[jj] = PetscAbsScalar(avals[jj]);
8001:         PetscCall(MatSeqAIJRestoreArray(c, &avals));
8002:       }
8003:     }
8004:   }
8005:   if (symmetrize) {
8006:     PetscBool isset, issym;
8007:     PetscCall(MatIsSymmetricKnown(Amat, &isset, &issym));
8008:     if (!isset || !issym) {
8009:       Mat matTrans;
8010:       PetscCall(MatTranspose(Gmat, MAT_INITIAL_MATRIX, &matTrans));
8011:       PetscCall(MatAXPY(Gmat, 1.0, matTrans, Gmat->structurally_symmetric == PETSC_BOOL3_TRUE ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN));
8012:       PetscCall(MatDestroy(&matTrans));
8013:     }
8014:     PetscCall(MatSetOption(Gmat, MAT_SYMMETRIC, PETSC_TRUE));
8015:   } else if (Amat != Gmat) PetscCall(MatPropagateSymmetryOptions(Amat, Gmat));
8016:   if (scale) {
8017:     /* scale c for all diagonal values = 1 or -1 */
8018:     Vec diag;
8019:     PetscCall(MatCreateVecs(Gmat, &diag, NULL));
8020:     PetscCall(MatGetDiagonal(Gmat, diag));
8021:     PetscCall(VecReciprocal(diag));
8022:     PetscCall(VecSqrtAbs(diag));
8023:     PetscCall(MatDiagonalScale(Gmat, diag, diag));
8024:     PetscCall(VecDestroy(&diag));
8025:   }
8026:   PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_graph_view"));

8028:   if (filter >= 0) {
8029:     PetscCall(MatFilter(Gmat, filter, PETSC_TRUE, PETSC_TRUE));
8030:     PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_filter_graph_view"));
8031:   }
8032:   *a_Gmat = Gmat;
8033:   PetscFunctionReturn(PETSC_SUCCESS);
8034: }

8036: /*
8037:     Special version for direct calls from Fortran
8038: */

8040: /* Change these macros so can be used in void function */
8041: /* Identical to PetscCallVoid, except it assigns to *_ierr */
8042: #undef PetscCall
8043: #define PetscCall(...) \
8044:   do { \
8045:     PetscErrorCode ierr_msv_mpiaij = __VA_ARGS__; \
8046:     if (PetscUnlikely(ierr_msv_mpiaij)) { \
8047:       *_ierr = PetscError(PETSC_COMM_SELF, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr_msv_mpiaij, PETSC_ERROR_REPEAT, " "); \
8048:       return; \
8049:     } \
8050:   } while (0)

8052: #undef SETERRQ
8053: #define SETERRQ(comm, ierr, ...) \
8054:   do { \
8055:     *_ierr = PetscError(comm, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr, PETSC_ERROR_INITIAL, __VA_ARGS__); \
8056:     return; \
8057:   } while (0)

8059: #if defined(PETSC_HAVE_FORTRAN_CAPS)
8060:   #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
8061: #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
8062:   #define matsetvaluesmpiaij_ matsetvaluesmpiaij
8063: #else
8064: #endif
8065: PETSC_EXTERN void matsetvaluesmpiaij_(Mat *mmat, PetscInt *mm, const PetscInt im[], PetscInt *mn, const PetscInt in[], const PetscScalar v[], InsertMode *maddv, PetscErrorCode *_ierr)
8066: {
8067:   Mat         mat = *mmat;
8068:   PetscInt    m = *mm, n = *mn;
8069:   InsertMode  addv = *maddv;
8070:   Mat_MPIAIJ *aij  = (Mat_MPIAIJ *)mat->data;
8071:   PetscScalar value;

8073:   MatCheckPreallocated(mat, 1);
8074:   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
8075:   else PetscCheck(mat->insertmode == addv, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Cannot mix add values and insert values");
8076:   {
8077:     PetscInt  i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
8078:     PetscInt  cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
8079:     PetscBool roworiented = aij->roworiented;

8081:     /* Some Variables required in the macro */
8082:     Mat         A     = aij->A;
8083:     Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
8084:     PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
8085:     MatScalar  *aa;
8086:     PetscBool   ignorezeroentries = ((a->ignorezeroentries && (addv == ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
8087:     Mat         B                 = aij->B;
8088:     Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
8089:     PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
8090:     MatScalar  *ba;
8091:     /* This variable below is only for the PETSC_HAVE_VIENNACL or PETSC_HAVE_CUDA cases, but we define it in all cases because we
8092:      * cannot use "#if defined" inside a macro. */
8093:     PETSC_UNUSED PetscBool inserted = PETSC_FALSE;

8095:     PetscInt  *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
8096:     PetscInt   nonew = a->nonew;
8097:     MatScalar *ap1, *ap2;

8099:     PetscFunctionBegin;
8100:     PetscCall(MatSeqAIJGetArray(A, &aa));
8101:     PetscCall(MatSeqAIJGetArray(B, &ba));
8102:     for (i = 0; i < m; i++) {
8103:       if (im[i] < 0) continue;
8104:       PetscCheck(im[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, im[i], mat->rmap->N - 1);
8105:       if (im[i] >= rstart && im[i] < rend) {
8106:         row      = im[i] - rstart;
8107:         lastcol1 = -1;
8108:         rp1      = aj + ai[row];
8109:         ap1      = aa + ai[row];
8110:         rmax1    = aimax[row];
8111:         nrow1    = ailen[row];
8112:         low1     = 0;
8113:         high1    = nrow1;
8114:         lastcol2 = -1;
8115:         rp2      = bj + bi[row];
8116:         ap2      = ba + bi[row];
8117:         rmax2    = bimax[row];
8118:         nrow2    = bilen[row];
8119:         low2     = 0;
8120:         high2    = nrow2;

8122:         for (j = 0; j < n; j++) {
8123:           if (roworiented) value = v[i * n + j];
8124:           else value = v[i + j * m];
8125:           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
8126:           if (in[j] >= cstart && in[j] < cend) {
8127:             col = in[j] - cstart;
8128:             MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
8129:           } else if (in[j] < 0) continue;
8130:           else if (PetscUnlikelyDebug(in[j] >= mat->cmap->N)) {
8131:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
8132:           } else {
8133:             if (mat->was_assembled) {
8134:               if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
8135: #if defined(PETSC_USE_CTABLE)
8136:               PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col));
8137:               col--;
8138: #else
8139:               col = aij->colmap[in[j]] - 1;
8140: #endif
8141:               if (col < 0 && !((Mat_SeqAIJ *)aij->A->data)->nonew) {
8142:                 PetscCall(MatDisAssemble_MPIAIJ(mat));
8143:                 col = in[j];
8144:                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
8145:                 B        = aij->B;
8146:                 b        = (Mat_SeqAIJ *)B->data;
8147:                 bimax    = b->imax;
8148:                 bi       = b->i;
8149:                 bilen    = b->ilen;
8150:                 bj       = b->j;
8151:                 rp2      = bj + bi[row];
8152:                 ap2      = ba + bi[row];
8153:                 rmax2    = bimax[row];
8154:                 nrow2    = bilen[row];
8155:                 low2     = 0;
8156:                 high2    = nrow2;
8157:                 bm       = aij->B->rmap->n;
8158:                 ba       = b->a;
8159:                 inserted = PETSC_FALSE;
8160:               }
8161:             } else col = in[j];
8162:             MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
8163:           }
8164:         }
8165:       } else if (!aij->donotstash) {
8166:         if (roworiented) {
8167:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, v + i * n, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8168:         } else {
8169:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, v + i, m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8170:         }
8171:       }
8172:     }
8173:     PetscCall(MatSeqAIJRestoreArray(A, &aa));
8174:     PetscCall(MatSeqAIJRestoreArray(B, &ba));
8175:   }
8176:   PetscFunctionReturnVoid();
8177: }

8179: /* Undefining these here since they were redefined from their original definition above! No
8180:  * other PETSc functions should be defined past this point, as it is impossible to recover the
8181:  * original definitions */
8182: #undef PetscCall
8183: #undef SETERRQ