Actual source code: xyt.c

  1: /*
  2: Module Name: xyt
  3: Module Info:

  5: author:  Henry M. Tufo III
  6: e-mail:  hmt@asci.uchicago.edu
  7: contact:
  8: +--------------------------------+--------------------------------+
  9: |MCS Division - Building 221     |Department of Computer Science  |
 10: |Argonne National Laboratory     |Ryerson 152                     |
 11: |9700 S. Cass Avenue             |The University of Chicago       |
 12: |Argonne, IL  60439              |Chicago, IL  60637              |
 13: |(630) 252-5354/5986 ph/fx       |(773) 702-6019/8487 ph/fx       |
 14: +--------------------------------+--------------------------------+

 16: Last Modification: 3.20.01
 17: */
 18: #include <../src/ksp/pc/impls/tfs/tfs.h>

 20: #define LEFT  -1
 21: #define RIGHT 1
 22: #define BOTH  0

 24: typedef struct xyt_solver_info {
 25:   PetscInt      n, m, n_global, m_global;
 26:   PetscInt      nnz, max_nnz, msg_buf_sz;
 27:   PetscInt     *nsep, *lnsep, *fo, nfo, *stages;
 28:   PetscInt     *xcol_sz, *xcol_indices;
 29:   PetscScalar **xcol_vals, *x, *solve_uu, *solve_w;
 30:   PetscInt     *ycol_sz, *ycol_indices;
 31:   PetscScalar **ycol_vals, *y;
 32:   PetscInt      nsolves;
 33:   PetscScalar   tot_solve_time;
 34: } xyt_info;

 36: typedef struct matvec_info {
 37:   PetscInt     n, m, n_global, m_global;
 38:   PetscInt    *local2global;
 39:   PCTFS_gs_ADT PCTFS_gs_handle;
 40:   PetscErrorCode (*matvec)(struct matvec_info *, PetscScalar *, PetscScalar *);
 41:   void *grid_data;
 42: } mv_info;

 44: struct xyt_CDT {
 45:   PetscInt  id;
 46:   PetscInt  ns;
 47:   PetscInt  level;
 48:   xyt_info *info;
 49:   mv_info  *mvi;
 50: };

 52: static PetscInt n_xyt         = 0;
 53: static PetscInt n_xyt_handles = 0;

 55: /* prototypes */
 56: static PetscErrorCode do_xyt_solve(xyt_ADT xyt_handle, PetscScalar *rhs);
 57: static PetscErrorCode check_handle(xyt_ADT xyt_handle);
 58: static PetscErrorCode det_separators(xyt_ADT xyt_handle);
 59: static PetscErrorCode do_matvec(mv_info *A, PetscScalar *v, PetscScalar *u);
 60: static PetscErrorCode xyt_generate(xyt_ADT xyt_handle);
 61: static PetscErrorCode do_xyt_factor(xyt_ADT xyt_handle);
 62: static mv_info       *set_mvi(PetscInt *local2global, PetscInt n, PetscInt m, PetscErrorCode (*matvec)(mv_info *, PetscScalar *, PetscScalar *), void *grid_data);

 64: xyt_ADT XYT_new(void)
 65: {
 66:   xyt_ADT xyt_handle;

 68:   /* rolling count on n_xyt ... pot. problem here */
 69:   n_xyt_handles++;
 70:   xyt_handle       = (xyt_ADT)malloc(sizeof(struct xyt_CDT));
 71:   xyt_handle->id   = ++n_xyt;
 72:   xyt_handle->info = NULL;
 73:   xyt_handle->mvi  = NULL;

 75:   return xyt_handle;
 76: }

 78: PetscErrorCode XYT_factor(xyt_ADT   xyt_handle,                                           /* prev. allocated xyt  handle */
 79:                           PetscInt *local2global,                                         /* global column mapping       */
 80:                           PetscInt  n,                                                    /* local num rows              */
 81:                           PetscInt  m,                                                    /* local num cols              */
 82:                           PetscErrorCode (*matvec)(void *, PetscScalar *, PetscScalar *), /* b_loc=A_local.x_loc         */
 83:                           void *grid_data)                                                /* grid data for matvec        */
 84: {
 85:   PetscFunctionBegin;
 86:   PetscCall(PCTFS_comm_init());
 87:   PetscCall(check_handle(xyt_handle));

 89:   /* only 2^k for now and all nodes participating */
 90:   PetscCheck((1 << (xyt_handle->level = PCTFS_i_log2_num_nodes)) == PCTFS_num_nodes, PETSC_COMM_SELF, PETSC_ERR_PLIB, "only 2^k for now and MPI_COMM_WORLD!!! %d != %d", 1 << PCTFS_i_log2_num_nodes, PCTFS_num_nodes);

 92:   /* space for X info */
 93:   xyt_handle->info = (xyt_info *)malloc(sizeof(xyt_info));

 95:   /* set up matvec handles */
 96:   xyt_handle->mvi = set_mvi(local2global, n, m, (PetscErrorCode (*)(mv_info *, PetscScalar *, PetscScalar *))matvec, grid_data);

 98:   /* matrix is assumed to be of full rank */
 99:   /* LATER we can reset to indicate rank def. */
100:   xyt_handle->ns = 0;

102:   /* determine separators and generate firing order - NB xyt info set here */
103:   PetscCall(det_separators(xyt_handle));

105:   PetscCall(do_xyt_factor(xyt_handle));
106:   PetscFunctionReturn(PETSC_SUCCESS);
107: }

109: PetscErrorCode XYT_solve(xyt_ADT xyt_handle, PetscScalar *x, PetscScalar *b)
110: {
111:   PetscFunctionBegin;
112:   PetscCall(PCTFS_comm_init());
113:   PetscCall(check_handle(xyt_handle));

115:   /* need to copy b into x? */
116:   if (b) PetscCall(PCTFS_rvec_copy(x, b, xyt_handle->mvi->n));
117:   PetscCall(do_xyt_solve(xyt_handle, x));
118:   PetscFunctionReturn(PETSC_SUCCESS);
119: }

121: PetscErrorCode XYT_free(xyt_ADT xyt_handle)
122: {
123:   PetscFunctionBegin;
124:   PetscCall(PCTFS_comm_init());
125:   PetscCall(check_handle(xyt_handle));
126:   n_xyt_handles--;

128:   free(xyt_handle->info->nsep);
129:   free(xyt_handle->info->lnsep);
130:   free(xyt_handle->info->fo);
131:   free(xyt_handle->info->stages);
132:   free(xyt_handle->info->solve_uu);
133:   free(xyt_handle->info->solve_w);
134:   free(xyt_handle->info->x);
135:   free(xyt_handle->info->xcol_vals);
136:   free(xyt_handle->info->xcol_sz);
137:   free(xyt_handle->info->xcol_indices);
138:   free(xyt_handle->info->y);
139:   free(xyt_handle->info->ycol_vals);
140:   free(xyt_handle->info->ycol_sz);
141:   free(xyt_handle->info->ycol_indices);
142:   free(xyt_handle->info);
143:   free(xyt_handle->mvi->local2global);
144:   PetscCall(PCTFS_gs_free(xyt_handle->mvi->PCTFS_gs_handle));
145:   free(xyt_handle->mvi);
146:   free(xyt_handle);

148:   /* if the check fails we nuke */
149:   /* if NULL pointer passed to free we nuke */
150:   /* if the calls to free fail that's not my problem */
151:   PetscFunctionReturn(PETSC_SUCCESS);
152: }

154: /* This function is currently not used */
155: PetscErrorCode XYT_stats(xyt_ADT xyt_handle)
156: {
157:   PetscInt    op[]  = {NON_UNIFORM, GL_MIN, GL_MAX, GL_ADD, GL_MIN, GL_MAX, GL_ADD, GL_MIN, GL_MAX, GL_ADD};
158:   PetscInt    fop[] = {NON_UNIFORM, GL_MIN, GL_MAX, GL_ADD};
159:   PetscInt    vals[9], work[9];
160:   PetscScalar fvals[3], fwork[3];

162:   PetscFunctionBegin;
163:   PetscCall(PCTFS_comm_init());
164:   PetscCall(check_handle(xyt_handle));

166:   /* if factorization not done there are no stats */
167:   if (!xyt_handle->info || !xyt_handle->mvi) {
168:     if (!PCTFS_my_id) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "XYT_stats() :: no stats available!\n"));
169:     PetscFunctionReturn(PETSC_SUCCESS);
170:   }

172:   vals[0] = vals[1] = vals[2] = xyt_handle->info->nnz;
173:   vals[3] = vals[4] = vals[5] = xyt_handle->mvi->n;
174:   vals[6] = vals[7] = vals[8] = xyt_handle->info->msg_buf_sz;
175:   PetscCall(PCTFS_giop(vals, work, PETSC_STATIC_ARRAY_LENGTH(op) - 1, op));

177:   fvals[0] = fvals[1] = fvals[2] = xyt_handle->info->tot_solve_time / xyt_handle->info->nsolves++;
178:   PetscCall(PCTFS_grop(fvals, fwork, PETSC_STATIC_ARRAY_LENGTH(fop) - 1, fop));

180:   if (!PCTFS_my_id) {
181:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: min   xyt_nnz=%" PetscInt_FMT "\n", PCTFS_my_id, vals[0]));
182:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: max   xyt_nnz=%" PetscInt_FMT "\n", PCTFS_my_id, vals[1]));
183:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: avg   xyt_nnz=%g\n", PCTFS_my_id, (double)(1.0 * vals[2] / PCTFS_num_nodes)));
184:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: tot   xyt_nnz=%" PetscInt_FMT "\n", PCTFS_my_id, vals[2]));
185:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: xyt   C(2d)  =%g\n", PCTFS_my_id, (double)(vals[2] / (PetscPowReal(1.0 * vals[5], 1.5)))));
186:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: xyt   C(3d)  =%g\n", PCTFS_my_id, (double)(vals[2] / (PetscPowReal(1.0 * vals[5], 1.6667)))));
187:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: min   xyt_n  =%" PetscInt_FMT "\n", PCTFS_my_id, vals[3]));
188:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: max   xyt_n  =%" PetscInt_FMT "\n", PCTFS_my_id, vals[4]));
189:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: avg   xyt_n  =%g\n", PCTFS_my_id, (double)(1.0 * vals[5] / PCTFS_num_nodes)));
190:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: tot   xyt_n  =%" PetscInt_FMT "\n", PCTFS_my_id, vals[5]));
191:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: min   xyt_buf=%" PetscInt_FMT "\n", PCTFS_my_id, vals[6]));
192:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: max   xyt_buf=%" PetscInt_FMT "\n", PCTFS_my_id, vals[7]));
193:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: avg   xyt_buf=%g\n", PCTFS_my_id, (double)(1.0 * vals[8] / PCTFS_num_nodes)));
194:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: min   xyt_slv=%g\n", PCTFS_my_id, (double)PetscRealPart(fvals[0])));
195:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: max   xyt_slv=%g\n", PCTFS_my_id, (double)PetscRealPart(fvals[1])));
196:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%d :: avg   xyt_slv=%g\n", PCTFS_my_id, (double)PetscRealPart(fvals[2] / PCTFS_num_nodes)));
197:   }
198:   PetscFunctionReturn(PETSC_SUCCESS);
199: }

201: /*

203: Description: get A_local, local portion of global coarse matrix which
204: is a row dist. nxm matrix w/ n<m.
205:    o my_ml holds address of ML struct associated w/A_local and coarse grid
206:    o local2global holds global number of column i (i=0,...,m-1)
207:    o local2global holds global number of row    i (i=0,...,n-1)
208:    o mylocmatvec performs A_local . vec_local (note that gs is performed using
209:    PCTFS_gs_init/gop).

211: mylocmatvec = my_ml->Amat[grid_tag].matvec->external;
212: mylocmatvec (void :: void *data, double *in, double *out)
213: */
214: static PetscErrorCode do_xyt_factor(xyt_ADT xyt_handle)
215: {
216:   return xyt_generate(xyt_handle);
217: }

219: static PetscErrorCode xyt_generate(xyt_ADT xyt_handle)
220: {
221:   PetscInt      i, j, k, idx;
222:   PetscInt      dim, col;
223:   PetscScalar  *u, *uu, *v, *z, *w, alpha, alpha_w;
224:   PetscInt     *segs;
225:   PetscInt      op[] = {GL_ADD, 0};
226:   PetscInt      off, len;
227:   PetscScalar  *x_ptr, *y_ptr;
228:   PetscInt     *iptr, flag;
229:   PetscInt      start = 0, end, work;
230:   PetscInt      op2[] = {GL_MIN, 0};
231:   PCTFS_gs_ADT  PCTFS_gs_handle;
232:   PetscInt     *nsep, *lnsep, *fo;
233:   PetscInt      a_n            = xyt_handle->mvi->n;
234:   PetscInt      a_m            = xyt_handle->mvi->m;
235:   PetscInt     *a_local2global = xyt_handle->mvi->local2global;
236:   PetscInt      level;
237:   PetscInt      n, m;
238:   PetscInt     *xcol_sz, *xcol_indices, *stages;
239:   PetscScalar **xcol_vals, *x;
240:   PetscInt     *ycol_sz, *ycol_indices;
241:   PetscScalar **ycol_vals, *y;
242:   PetscInt      n_global;
243:   PetscInt      xt_nnz = 0, xt_max_nnz = 0;
244:   PetscInt      yt_nnz = 0, yt_max_nnz = 0;
245:   PetscBLASInt  i1  = 1, dlen;
246:   PetscScalar   dm1 = -1.0;

248:   n               = xyt_handle->mvi->n;
249:   nsep            = xyt_handle->info->nsep;
250:   lnsep           = xyt_handle->info->lnsep;
251:   fo              = xyt_handle->info->fo;
252:   end             = lnsep[0];
253:   level           = xyt_handle->level;
254:   PCTFS_gs_handle = xyt_handle->mvi->PCTFS_gs_handle;

256:   /* is there a null space? */
257:   /* LATER add in ability to detect null space by checking alpha */
258:   for (i = 0, j = 0; i <= level; i++) j += nsep[i];

260:   m = j - xyt_handle->ns;
261:   if (m != j) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "xyt_generate() :: null space exists %" PetscInt_FMT " %" PetscInt_FMT " %" PetscInt_FMT "\n", m, j, xyt_handle->ns));

263:   PetscCall(PetscInfo(0, "xyt_generate() :: X(%" PetscInt_FMT ",%" PetscInt_FMT ")\n", n, m));

265:   /* get and initialize storage for x local         */
266:   /* note that x local is nxm and stored by columns */
267:   xcol_sz      = (PetscInt *)malloc(m * sizeof(PetscInt));
268:   xcol_indices = (PetscInt *)malloc((2 * m + 1) * sizeof(PetscInt));
269:   xcol_vals    = (PetscScalar **)malloc(m * sizeof(PetscScalar *));
270:   for (i = j = 0; i < m; i++, j += 2) {
271:     xcol_indices[j] = xcol_indices[j + 1] = xcol_sz[i] = -1;
272:     xcol_vals[i]                                       = NULL;
273:   }
274:   xcol_indices[j] = -1;

276:   /* get and initialize storage for y local         */
277:   /* note that y local is nxm and stored by columns */
278:   ycol_sz      = (PetscInt *)malloc(m * sizeof(PetscInt));
279:   ycol_indices = (PetscInt *)malloc((2 * m + 1) * sizeof(PetscInt));
280:   ycol_vals    = (PetscScalar **)malloc(m * sizeof(PetscScalar *));
281:   for (i = j = 0; i < m; i++, j += 2) {
282:     ycol_indices[j] = ycol_indices[j + 1] = ycol_sz[i] = -1;
283:     ycol_vals[i]                                       = NULL;
284:   }
285:   ycol_indices[j] = -1;

287:   /* size of separators for each sub-hc working from bottom of tree to top */
288:   /* this looks like nsep[]=segments */
289:   stages = (PetscInt *)malloc((level + 1) * sizeof(PetscInt));
290:   segs   = (PetscInt *)malloc((level + 1) * sizeof(PetscInt));
291:   PetscCall(PCTFS_ivec_zero(stages, level + 1));
292:   PCTFS_ivec_copy(segs, nsep, level + 1);
293:   for (i = 0; i < level; i++) segs[i + 1] += segs[i];
294:   stages[0] = segs[0];

296:   /* temporary vectors  */
297:   u  = (PetscScalar *)malloc(n * sizeof(PetscScalar));
298:   z  = (PetscScalar *)malloc(n * sizeof(PetscScalar));
299:   v  = (PetscScalar *)malloc(a_m * sizeof(PetscScalar));
300:   uu = (PetscScalar *)malloc(m * sizeof(PetscScalar));
301:   w  = (PetscScalar *)malloc(m * sizeof(PetscScalar));

303:   /* extra nnz due to replication of vertices across separators */
304:   for (i = 1, j = 0; i <= level; i++) j += nsep[i];

306:   /* storage for sparse x values */
307:   n_global   = xyt_handle->info->n_global;
308:   xt_max_nnz = yt_max_nnz = (PetscInt)(2.5 * PetscPowReal(1.0 * n_global, 1.6667) + j * n / 2) / PCTFS_num_nodes;
309:   x                       = (PetscScalar *)malloc(xt_max_nnz * sizeof(PetscScalar));
310:   y                       = (PetscScalar *)malloc(yt_max_nnz * sizeof(PetscScalar));

312:   /* LATER - can embed next sep to fire in gs */
313:   /* time to make the donuts - generate X factor */
314:   for (dim = i = j = 0; i < m; i++) {
315:     /* time to move to the next level? */
316:     while (i == segs[dim]) {
317:       PetscCheck(dim != level, PETSC_COMM_SELF, PETSC_ERR_PLIB, "dim about to exceed level");
318:       stages[dim++] = i;
319:       end += lnsep[dim];
320:     }
321:     stages[dim] = i;

323:     /* which column are we firing? */
324:     /* i.e. set v_l */
325:     /* use new seps and do global min across hc to determine which one to fire */
326:     (start < end) ? (col = fo[start]) : (col = INT_MAX);
327:     PetscCall(PCTFS_giop_hc(&col, &work, 1, op2, dim));

329:     /* shouldn't need this */
330:     if (col == INT_MAX) {
331:       PetscCall(PetscInfo(0, "hey ... col==INT_MAX??\n"));
332:       continue;
333:     }

335:     /* do I own it? I should */
336:     PetscCall(PCTFS_rvec_zero(v, a_m));
337:     if (col == fo[start]) {
338:       start++;
339:       idx = PCTFS_ivec_linear_search(col, a_local2global, a_n);
340:       PetscCheck(idx != -1, PETSC_COMM_SELF, PETSC_ERR_PLIB, "NOT FOUND!");
341:       v[idx] = 1.0;
342:       j++;
343:     } else {
344:       idx = PCTFS_ivec_linear_search(col, a_local2global, a_m);
345:       if (idx != -1) v[idx] = 1.0;
346:     }

348:     /* perform u = A.v_l */
349:     PetscCall(PCTFS_rvec_zero(u, n));
350:     PetscCall(do_matvec(xyt_handle->mvi, v, u));

352:     /* uu =  X^T.u_l (local portion) */
353:     /* technically only need to zero out first i entries */
354:     /* later turn this into an XYT_solve call ? */
355:     PetscCall(PCTFS_rvec_zero(uu, m));
356:     y_ptr = y;
357:     iptr  = ycol_indices;
358:     for (k = 0; k < i; k++) {
359:       off = *iptr++;
360:       len = *iptr++;
361:       PetscCall(PetscBLASIntCast(len, &dlen));
362:       PetscCallBLAS("BLASdot", uu[k] = BLASdot_(&dlen, u + off, &i1, y_ptr, &i1));
363:       y_ptr += len;
364:     }

366:     /* uu = X^T.u_l (comm portion) */
367:     PetscCall(PCTFS_ssgl_radd(uu, w, dim, stages));

369:     /* z = X.uu */
370:     PetscCall(PCTFS_rvec_zero(z, n));
371:     x_ptr = x;
372:     iptr  = xcol_indices;
373:     for (k = 0; k < i; k++) {
374:       off = *iptr++;
375:       len = *iptr++;
376:       PetscCall(PetscBLASIntCast(len, &dlen));
377:       PetscCallBLAS("BLASaxpy", BLASaxpy_(&dlen, &uu[k], x_ptr, &i1, z + off, &i1));
378:       x_ptr += len;
379:     }

381:     /* compute v_l = v_l - z */
382:     PetscCall(PCTFS_rvec_zero(v + a_n, a_m - a_n));
383:     PetscCall(PetscBLASIntCast(n, &dlen));
384:     PetscCallBLAS("BLASaxpy", BLASaxpy_(&dlen, &dm1, z, &i1, v, &i1));

386:     /* compute u_l = A.v_l */
387:     if (a_n != a_m) PetscCall(PCTFS_gs_gop_hc(PCTFS_gs_handle, v, "+\0", dim));
388:     PetscCall(PCTFS_rvec_zero(u, n));
389:     PetscCall(do_matvec(xyt_handle->mvi, v, u));

391:     /* compute sqrt(alpha) = sqrt(u_l^T.u_l) - local portion */
392:     PetscCall(PetscBLASIntCast(n, &dlen));
393:     PetscCallBLAS("BLASdot", alpha = BLASdot_(&dlen, u, &i1, u, &i1));
394:     /* compute sqrt(alpha) = sqrt(u_l^T.u_l) - comm portion */
395:     PetscCall(PCTFS_grop_hc(&alpha, &alpha_w, 1, op, dim));

397:     alpha = (PetscScalar)PetscSqrtReal((PetscReal)alpha);

399:     /* check for small alpha                             */
400:     /* LATER use this to detect and determine null space */
401:     PetscCheck(PetscAbsScalar(alpha) >= 1.0e-14, PETSC_COMM_SELF, PETSC_ERR_PLIB, "bad alpha! %g", (double)PetscAbsScalar(alpha));

403:     /* compute v_l = v_l/sqrt(alpha) */
404:     PetscCall(PCTFS_rvec_scale(v, 1.0 / alpha, n));
405:     PetscCall(PCTFS_rvec_scale(u, 1.0 / alpha, n));

407:     /* add newly generated column, v_l, to X */
408:     flag = 1;
409:     off = len = 0;
410:     for (k = 0; k < n; k++) {
411:       if (v[k] != 0.0) {
412:         len = k;
413:         if (flag) {
414:           off  = k;
415:           flag = 0;
416:         }
417:       }
418:     }

420:     len -= (off - 1);

422:     if (len > 0) {
423:       if ((xt_nnz + len) > xt_max_nnz) {
424:         PetscCall(PetscInfo(0, "increasing space for X by 2x!\n"));
425:         xt_max_nnz *= 2;
426:         x_ptr = (PetscScalar *)malloc(xt_max_nnz * sizeof(PetscScalar));
427:         PetscCall(PCTFS_rvec_copy(x_ptr, x, xt_nnz));
428:         free(x);
429:         x = x_ptr;
430:         x_ptr += xt_nnz;
431:       }
432:       xt_nnz += len;
433:       PetscCall(PCTFS_rvec_copy(x_ptr, v + off, len));

435:       xcol_indices[2 * i] = off;
436:       xcol_sz[i] = xcol_indices[2 * i + 1] = len;
437:       xcol_vals[i]                         = x_ptr;
438:     } else {
439:       xcol_indices[2 * i] = 0;
440:       xcol_sz[i] = xcol_indices[2 * i + 1] = 0;
441:       xcol_vals[i]                         = x_ptr;
442:     }

444:     /* add newly generated column, u_l, to Y */
445:     flag = 1;
446:     off = len = 0;
447:     for (k = 0; k < n; k++) {
448:       if (u[k] != 0.0) {
449:         len = k;
450:         if (flag) {
451:           off  = k;
452:           flag = 0;
453:         }
454:       }
455:     }

457:     len -= (off - 1);

459:     if (len > 0) {
460:       if ((yt_nnz + len) > yt_max_nnz) {
461:         PetscCall(PetscInfo(0, "increasing space for Y by 2x!\n"));
462:         yt_max_nnz *= 2;
463:         y_ptr = (PetscScalar *)malloc(yt_max_nnz * sizeof(PetscScalar));
464:         PetscCall(PCTFS_rvec_copy(y_ptr, y, yt_nnz));
465:         free(y);
466:         y = y_ptr;
467:         y_ptr += yt_nnz;
468:       }
469:       yt_nnz += len;
470:       PetscCall(PCTFS_rvec_copy(y_ptr, u + off, len));

472:       ycol_indices[2 * i] = off;
473:       ycol_sz[i] = ycol_indices[2 * i + 1] = len;
474:       ycol_vals[i]                         = y_ptr;
475:     } else {
476:       ycol_indices[2 * i] = 0;
477:       ycol_sz[i] = ycol_indices[2 * i + 1] = 0;
478:       ycol_vals[i]                         = y_ptr;
479:     }
480:   }

482:   /* close off stages for execution phase */
483:   while (dim != level) {
484:     stages[dim++] = i;
485:     PetscCall(PetscInfo(0, "disconnected!!! dim(%" PetscInt_FMT ")!=level(%" PetscInt_FMT ")\n", dim, level));
486:   }
487:   stages[dim] = i;

489:   xyt_handle->info->n            = xyt_handle->mvi->n;
490:   xyt_handle->info->m            = m;
491:   xyt_handle->info->nnz          = xt_nnz + yt_nnz;
492:   xyt_handle->info->max_nnz      = xt_max_nnz + yt_max_nnz;
493:   xyt_handle->info->msg_buf_sz   = stages[level] - stages[0];
494:   xyt_handle->info->solve_uu     = (PetscScalar *)malloc(m * sizeof(PetscScalar));
495:   xyt_handle->info->solve_w      = (PetscScalar *)malloc(m * sizeof(PetscScalar));
496:   xyt_handle->info->x            = x;
497:   xyt_handle->info->xcol_vals    = xcol_vals;
498:   xyt_handle->info->xcol_sz      = xcol_sz;
499:   xyt_handle->info->xcol_indices = xcol_indices;
500:   xyt_handle->info->stages       = stages;
501:   xyt_handle->info->y            = y;
502:   xyt_handle->info->ycol_vals    = ycol_vals;
503:   xyt_handle->info->ycol_sz      = ycol_sz;
504:   xyt_handle->info->ycol_indices = ycol_indices;

506:   free(segs);
507:   free(u);
508:   free(v);
509:   free(uu);
510:   free(z);
511:   free(w);

513:   return PETSC_SUCCESS;
514: }

516: static PetscErrorCode do_xyt_solve(xyt_ADT xyt_handle, PetscScalar *uc)
517: {
518:   PetscInt     off, len, *iptr;
519:   PetscInt     level        = xyt_handle->level;
520:   PetscInt     n            = xyt_handle->info->n;
521:   PetscInt     m            = xyt_handle->info->m;
522:   PetscInt    *stages       = xyt_handle->info->stages;
523:   PetscInt    *xcol_indices = xyt_handle->info->xcol_indices;
524:   PetscInt    *ycol_indices = xyt_handle->info->ycol_indices;
525:   PetscScalar *x_ptr, *y_ptr, *uu_ptr;
526:   PetscScalar *solve_uu = xyt_handle->info->solve_uu;
527:   PetscScalar *solve_w  = xyt_handle->info->solve_w;
528:   PetscScalar *x        = xyt_handle->info->x;
529:   PetscScalar *y        = xyt_handle->info->y;
530:   PetscBLASInt i1       = 1, dlen;

532:   PetscFunctionBegin;
533:   uu_ptr = solve_uu;
534:   PetscCall(PCTFS_rvec_zero(uu_ptr, m));

536:   /* x  = X.Y^T.b */
537:   /* uu = Y^T.b */
538:   for (y_ptr = y, iptr = ycol_indices; *iptr != -1; y_ptr += len) {
539:     off = *iptr++;
540:     len = *iptr++;
541:     PetscCall(PetscBLASIntCast(len, &dlen));
542:     PetscCallBLAS("BLASdot", *uu_ptr++ = BLASdot_(&dlen, uc + off, &i1, y_ptr, &i1));
543:   }

545:   /* communication of beta */
546:   uu_ptr = solve_uu;
547:   if (level) PetscCall(PCTFS_ssgl_radd(uu_ptr, solve_w, level, stages));
548:   PetscCall(PCTFS_rvec_zero(uc, n));

550:   /* x = X.uu */
551:   for (x_ptr = x, iptr = xcol_indices; *iptr != -1; x_ptr += len) {
552:     off = *iptr++;
553:     len = *iptr++;
554:     PetscCall(PetscBLASIntCast(len, &dlen));
555:     PetscCallBLAS("BLASaxpy", BLASaxpy_(&dlen, uu_ptr++, x_ptr, &i1, uc + off, &i1));
556:   }
557:   PetscFunctionReturn(PETSC_SUCCESS);
558: }

560: static PetscErrorCode check_handle(xyt_ADT xyt_handle)
561: {
562:   PetscInt vals[2], work[2], op[] = {NON_UNIFORM, GL_MIN, GL_MAX};

564:   PetscFunctionBegin;
565:   PetscCheck(xyt_handle, PETSC_COMM_SELF, PETSC_ERR_PLIB, "check_handle() :: bad handle :: NULL %p", (void *)xyt_handle);

567:   vals[0] = vals[1] = xyt_handle->id;
568:   PetscCall(PCTFS_giop(vals, work, PETSC_STATIC_ARRAY_LENGTH(op) - 1, op));
569:   PetscCheck(!(vals[0] != vals[1]) && !(xyt_handle->id <= 0), PETSC_COMM_SELF, PETSC_ERR_PLIB, "check_handle() :: bad handle :: id mismatch min/max %" PetscInt_FMT "/%" PetscInt_FMT " %" PetscInt_FMT, vals[0], vals[1], xyt_handle->id);
570:   PetscFunctionReturn(PETSC_SUCCESS);
571: }

573: static PetscErrorCode det_separators(xyt_ADT xyt_handle)
574: {
575:   PetscInt     i, ct, id;
576:   PetscInt     mask, edge, *iptr;
577:   PetscInt    *dir, *used;
578:   PetscInt     sum[4], w[4];
579:   PetscScalar  rsum[4], rw[4];
580:   PetscInt     op[] = {GL_ADD, 0};
581:   PetscScalar *lhs, *rhs;
582:   PetscInt    *nsep, *lnsep, *fo, nfo = 0;
583:   PCTFS_gs_ADT PCTFS_gs_handle = xyt_handle->mvi->PCTFS_gs_handle;
584:   PetscInt    *local2global    = xyt_handle->mvi->local2global;
585:   PetscInt     n               = xyt_handle->mvi->n;
586:   PetscInt     m               = xyt_handle->mvi->m;
587:   PetscInt     level           = xyt_handle->level;
588:   PetscInt     shared          = 0;

590:   PetscFunctionBegin;
591:   dir   = (PetscInt *)malloc(sizeof(PetscInt) * (level + 1));
592:   nsep  = (PetscInt *)malloc(sizeof(PetscInt) * (level + 1));
593:   lnsep = (PetscInt *)malloc(sizeof(PetscInt) * (level + 1));
594:   fo    = (PetscInt *)malloc(sizeof(PetscInt) * (n + 1));
595:   used  = (PetscInt *)malloc(sizeof(PetscInt) * n);

597:   PetscCall(PCTFS_ivec_zero(dir, level + 1));
598:   PetscCall(PCTFS_ivec_zero(nsep, level + 1));
599:   PetscCall(PCTFS_ivec_zero(lnsep, level + 1));
600:   PetscCall(PCTFS_ivec_set(fo, -1, n + 1));
601:   PetscCall(PCTFS_ivec_zero(used, n));

603:   lhs = (PetscScalar *)malloc(sizeof(PetscScalar) * m);
604:   rhs = (PetscScalar *)malloc(sizeof(PetscScalar) * m);

606:   /* determine the # of unique dof */
607:   PetscCall(PCTFS_rvec_zero(lhs, m));
608:   PetscCall(PCTFS_rvec_set(lhs, 1.0, n));
609:   PetscCall(PCTFS_gs_gop_hc(PCTFS_gs_handle, lhs, "+\0", level));
610:   PetscCall(PetscInfo(0, "done first PCTFS_gs_gop_hc\n"));
611:   PetscCall(PCTFS_rvec_zero(rsum, 2));
612:   for (i = 0; i < n; i++) {
613:     if (lhs[i] != 0.0) {
614:       rsum[0] += 1.0 / lhs[i];
615:       rsum[1] += lhs[i];
616:     }
617:     if (lhs[i] != 1.0) shared = 1;
618:   }

620:   PetscCall(PCTFS_grop_hc(rsum, rw, 2, op, level));
621:   rsum[0] += 0.1;
622:   rsum[1] += 0.1;

624:   xyt_handle->info->n_global = xyt_handle->info->m_global = (PetscInt)rsum[0];
625:   xyt_handle->mvi->n_global = xyt_handle->mvi->m_global = (PetscInt)rsum[0];

627:   /* determine separator sets top down */
628:   PetscCheck(!shared, PETSC_COMM_SELF, PETSC_ERR_PLIB, "shared dof separator determination not ready ... see hmt!!!");
629:   /* solution is to do as in the symmetric shared case but then */
630:   /* pick the sub-hc with the most free dofs and do a mat-vec   */
631:   /* and pick up the responses on the other sub-hc from the     */
632:   /* initial separator set obtained from the symm. shared case  */
633:   /* [dead code deleted since it is unlikely to be completed] */
634:   for (iptr = fo + n, id = PCTFS_my_id, mask = PCTFS_num_nodes >> 1, edge = level; edge > 0; edge--, mask >>= 1) {
635:     /* set rsh of hc, fire, and collect lhs responses */
636:     PetscCall((id < mask) ? PCTFS_rvec_zero(lhs, m) : PCTFS_rvec_set(lhs, 1.0, m));
637:     PetscCall(PCTFS_gs_gop_hc(PCTFS_gs_handle, lhs, "+\0", edge));

639:     /* set lsh of hc, fire, and collect rhs responses */
640:     PetscCall((id < mask) ? PCTFS_rvec_set(rhs, 1.0, m) : PCTFS_rvec_zero(rhs, m));
641:     PetscCall(PCTFS_gs_gop_hc(PCTFS_gs_handle, rhs, "+\0", edge));

643:     /* count number of dofs I own that have signal and not in sep set */
644:     PetscCall(PCTFS_ivec_zero(sum, 4));
645:     for (ct = i = 0; i < n; i++) {
646:       if (!used[i]) {
647:         /* number of unmarked dofs on node */
648:         ct++;
649:         /* number of dofs to be marked on lhs hc */
650:         if ((id < mask) && (lhs[i] != 0.0)) sum[0]++;
651:         /* number of dofs to be marked on rhs hc */
652:         if ((id >= mask) && (rhs[i] != 0.0)) sum[1]++;
653:       }
654:     }

656:     /* for the non-symmetric case we need separators of width 2 */
657:     /* so take both sides */
658:     (id < mask) ? (sum[2] = ct) : (sum[3] = ct);
659:     PetscCall(PCTFS_giop_hc(sum, w, 4, op, edge));

661:     ct = 0;
662:     if (id < mask) {
663:       /* mark dofs I own that have signal and not in sep set */
664:       for (i = 0; i < n; i++) {
665:         if ((!used[i]) && (lhs[i] != 0.0)) {
666:           ct++;
667:           nfo++;
668:           *--iptr = local2global[i];
669:           used[i] = edge;
670:         }
671:       }
672:       /* LSH hc summation of ct should be sum[0] */
673:     } else {
674:       /* mark dofs I own that have signal and not in sep set */
675:       for (i = 0; i < n; i++) {
676:         if ((!used[i]) && (rhs[i] != 0.0)) {
677:           ct++;
678:           nfo++;
679:           *--iptr = local2global[i];
680:           used[i] = edge;
681:         }
682:       }
683:       /* RSH hc summation of ct should be sum[1] */
684:     }

686:     if (ct > 1) PetscCall(PCTFS_ivec_sort(iptr, ct));
687:     lnsep[edge] = ct;
688:     nsep[edge]  = sum[0] + sum[1];
689:     dir[edge]   = BOTH;

691:     /* LATER or we can recur on these to order seps at this level */
692:     /* do we need full set of separators for this?                */

694:     /* fold rhs hc into lower */
695:     if (id >= mask) id -= mask;
696:   }

698:   /* level 0 is on processor case - so mark the remainder */
699:   for (ct = i = 0; i < n; i++) {
700:     if (!used[i]) {
701:       ct++;
702:       nfo++;
703:       *--iptr = local2global[i];
704:       used[i] = edge;
705:     }
706:   }
707:   if (ct > 1) PetscCall(PCTFS_ivec_sort(iptr, ct));
708:   lnsep[edge] = ct;
709:   nsep[edge]  = ct;
710:   dir[edge]   = BOTH;

712:   xyt_handle->info->nsep  = nsep;
713:   xyt_handle->info->lnsep = lnsep;
714:   xyt_handle->info->fo    = fo;
715:   xyt_handle->info->nfo   = nfo;

717:   free(dir);
718:   free(lhs);
719:   free(rhs);
720:   free(used);
721:   PetscFunctionReturn(PETSC_SUCCESS);
722: }

724: static mv_info *set_mvi(PetscInt *local2global, PetscInt n, PetscInt m, PetscErrorCode (*matvec)(mv_info *, PetscScalar *, PetscScalar *), void *grid_data)
725: {
726:   mv_info *mvi;

728:   mvi               = (mv_info *)malloc(sizeof(mv_info));
729:   mvi->n            = n;
730:   mvi->m            = m;
731:   mvi->n_global     = -1;
732:   mvi->m_global     = -1;
733:   mvi->local2global = (PetscInt *)malloc((m + 1) * sizeof(PetscInt));

735:   PCTFS_ivec_copy(mvi->local2global, local2global, m);
736:   mvi->local2global[m] = INT_MAX;
737:   mvi->matvec          = matvec;
738:   mvi->grid_data       = grid_data;

740:   /* set xyt communication handle to perform restricted matvec */
741:   mvi->PCTFS_gs_handle = PCTFS_gs_init(local2global, m, PCTFS_num_nodes);

743:   return mvi;
744: }

746: static PetscErrorCode do_matvec(mv_info *A, PetscScalar *v, PetscScalar *u)
747: {
748:   PetscFunctionBegin;
749:   PetscCall(A->matvec((mv_info *)A->grid_data, v, u));
750:   PetscFunctionReturn(PETSC_SUCCESS);
751: }