Actual source code: bddcgraph.c

  1: #include <petsc/private/petscimpl.h>
  2: #include <petsc/private/pcbddcprivateimpl.h>
  3: #include <petsc/private/pcbddcstructsimpl.h>
  4: #include <petsc/private/hashmapi.h>
  5: #include <petsc/private/pcbddcgraphhashmap.h>
  6: #include <petscsf.h>

  8: PetscErrorCode PCBDDCDestroyGraphCandidatesIS(void **ctx)
  9: {
 10:   PCBDDCGraphCandidates cand = (PCBDDCGraphCandidates)*ctx;

 12:   PetscFunctionBegin;
 13:   for (PetscInt i = 0; i < cand->nfc; i++) PetscCall(ISDestroy(&cand->Faces[i]));
 14:   for (PetscInt i = 0; i < cand->nec; i++) PetscCall(ISDestroy(&cand->Edges[i]));
 15:   PetscCall(PetscFree(cand->Faces));
 16:   PetscCall(PetscFree(cand->Edges));
 17:   PetscCall(ISDestroy(&cand->Vertices));
 18:   PetscCall(PetscFree(cand));
 19:   PetscFunctionReturn(PETSC_SUCCESS);
 20: }

 22: PetscErrorCode PCBDDCGraphGetDirichletDofsB(PCBDDCGraph graph, IS *dirdofs)
 23: {
 24:   PetscFunctionBegin;
 25:   if (graph->dirdofsB) {
 26:     PetscCall(PetscObjectReference((PetscObject)graph->dirdofsB));
 27:   } else if (graph->has_dirichlet) {
 28:     PetscInt  i, size;
 29:     PetscInt *dirdofs_idxs;

 31:     size = 0;
 32:     for (i = 0; i < graph->nvtxs; i++) {
 33:       if (graph->nodes[i].count > 1 && graph->nodes[i].special_dof == PCBDDCGRAPH_DIRICHLET_MARK) size++;
 34:     }

 36:     PetscCall(PetscMalloc1(size, &dirdofs_idxs));
 37:     size = 0;
 38:     for (i = 0; i < graph->nvtxs; i++) {
 39:       if (graph->nodes[i].count > 1 && graph->nodes[i].special_dof == PCBDDCGRAPH_DIRICHLET_MARK) dirdofs_idxs[size++] = i;
 40:     }
 41:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, size, dirdofs_idxs, PETSC_OWN_POINTER, &graph->dirdofsB));
 42:     PetscCall(PetscObjectReference((PetscObject)graph->dirdofsB));
 43:   }
 44:   *dirdofs = graph->dirdofsB;
 45:   PetscFunctionReturn(PETSC_SUCCESS);
 46: }

 48: PetscErrorCode PCBDDCGraphGetDirichletDofs(PCBDDCGraph graph, IS *dirdofs)
 49: {
 50:   PetscFunctionBegin;
 51:   if (graph->dirdofs) {
 52:     PetscCall(PetscObjectReference((PetscObject)graph->dirdofs));
 53:   } else if (graph->has_dirichlet) {
 54:     PetscInt  i, size;
 55:     PetscInt *dirdofs_idxs;

 57:     size = 0;
 58:     for (i = 0; i < graph->nvtxs; i++) {
 59:       if (graph->nodes[i].special_dof == PCBDDCGRAPH_DIRICHLET_MARK) size++;
 60:     }

 62:     PetscCall(PetscMalloc1(size, &dirdofs_idxs));
 63:     size = 0;
 64:     for (i = 0; i < graph->nvtxs; i++) {
 65:       if (graph->nodes[i].special_dof == PCBDDCGRAPH_DIRICHLET_MARK) dirdofs_idxs[size++] = i;
 66:     }
 67:     PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)graph->l2gmap), size, dirdofs_idxs, PETSC_OWN_POINTER, &graph->dirdofs));
 68:     PetscCall(PetscObjectReference((PetscObject)graph->dirdofs));
 69:   }
 70:   *dirdofs = graph->dirdofs;
 71:   PetscFunctionReturn(PETSC_SUCCESS);
 72: }

 74: PetscErrorCode PCBDDCGraphASCIIView(PCBDDCGraph graph, PetscInt verbosity_level, PetscViewer viewer)
 75: {
 76:   PetscInt  i, j, tabs;
 77:   PetscInt *queue_in_global_numbering;

 79:   PetscFunctionBegin;
 80:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(graph->seq_graph ? PETSC_COMM_SELF : PetscObjectComm((PetscObject)graph->l2gmap), &viewer));
 81:   PetscCall(PetscViewerASCIIPushSynchronized(viewer));
 82:   PetscCall(PetscViewerASCIIGetTab(viewer, &tabs));
 83:   PetscCall(PetscViewerASCIIPrintf(viewer, "--------------------------------------------------\n"));
 84:   PetscCall(PetscViewerFlush(viewer));
 85:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Local BDDC graph for subdomain %04d (seq %d)\n", PetscGlobalRank, graph->seq_graph));
 86:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Number of vertices %" PetscInt_FMT "\n", graph->nvtxs));
 87:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Number of local subdomains %" PetscInt_FMT "\n", graph->n_local_subs ? graph->n_local_subs : 1));
 88:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Custom minimal size %" PetscInt_FMT "\n", graph->custom_minimal_size));
 89:   if (graph->maxcount != PETSC_INT_MAX) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Max count %" PetscInt_FMT "\n", graph->maxcount));
 90:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Topological two dim? %s (set %s)\n", PetscBools[graph->twodim], PetscBools[graph->twodimset]));
 91:   if (verbosity_level > 2) {
 92:     for (i = 0; i < graph->nvtxs; i++) {
 93:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "%" PetscInt_FMT ":\n", i));
 94:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   which_dof: %" PetscInt_FMT "\n", graph->nodes[i].which_dof));
 95:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   special_dof: %" PetscInt_FMT "\n", graph->nodes[i].special_dof));
 96:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   shared by: %" PetscInt_FMT "\n", graph->nodes[i].count));
 97:       PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_FALSE));
 98:       if (graph->nodes[i].count) {
 99:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "     set of neighbours:"));
100:         for (j = 0; j < graph->nodes[i].count; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, graph->nodes[i].neighbours_set[j]));
101:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
102:       }
103:       PetscCall(PetscViewerASCIISetTab(viewer, tabs));
104:       PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_TRUE));
105:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   number of local groups: %" PetscInt_FMT "\n", graph->nodes[i].local_groups_count));
106:       PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_FALSE));
107:       if (graph->nodes[i].local_groups_count) {
108:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "     groups:"));
109:         for (j = 0; j < graph->nodes[i].local_groups_count; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, graph->nodes[i].local_groups[j]));
110:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
111:       }
112:       PetscCall(PetscViewerASCIISetTab(viewer, tabs));
113:       PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_TRUE));

115:       if (verbosity_level > 3) {
116:         if (graph->xadj) {
117:           PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   local adj list:"));
118:           PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_FALSE));
119:           for (j = graph->xadj[i]; j < graph->xadj[i + 1]; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, graph->adjncy[j]));
120:           PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
121:           PetscCall(PetscViewerASCIISetTab(viewer, tabs));
122:           PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_TRUE));
123:         } else {
124:           PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   no adj info\n"));
125:         }
126:       }
127:       if (graph->n_local_subs) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   local sub id: %" PetscInt_FMT "\n", graph->local_subs[i]));
128:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   interface subset id: %" PetscInt_FMT "\n", graph->nodes[i].subset));
129:       if (graph->nodes[i].subset && graph->subset_ncc) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   ncc for subset: %" PetscInt_FMT "\n", graph->subset_ncc[graph->nodes[i].subset - 1]));
130:     }
131:   }
132:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Total number of connected components %" PetscInt_FMT "\n", graph->ncc));
133:   PetscCall(PetscMalloc1(graph->cptr[graph->ncc], &queue_in_global_numbering));
134:   PetscCall(ISLocalToGlobalMappingApply(graph->l2gmap, graph->cptr[graph->ncc], graph->queue, queue_in_global_numbering));
135:   for (i = 0; i < graph->ncc; i++) {
136:     PetscInt  node_num = graph->queue[graph->cptr[i]];
137:     PetscBool printcc  = PETSC_FALSE;
138:     PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "  cc %" PetscInt_FMT " (size %" PetscInt_FMT ", fid %" PetscInt_FMT ", neighs:", i, graph->cptr[i + 1] - graph->cptr[i], graph->nodes[node_num].which_dof));
139:     PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_FALSE));
140:     for (j = 0; j < graph->nodes[node_num].count; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, graph->nodes[node_num].neighbours_set[j]));
141:     if (verbosity_level > 1) {
142:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "):"));
143:       if (verbosity_level > 2 || graph->twodim || graph->nodes[node_num].count > 2 || (graph->nodes[node_num].count == 2 && graph->nodes[node_num].special_dof == PCBDDCGRAPH_NEUMANN_MARK)) printcc = PETSC_TRUE;
144:       if (printcc) {
145:         for (j = graph->cptr[i]; j < graph->cptr[i + 1]; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT " (%" PetscInt_FMT ")", graph->queue[j], queue_in_global_numbering[j]));
146:       }
147:     } else {
148:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, ")"));
149:     }
150:     PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
151:     PetscCall(PetscViewerASCIISetTab(viewer, tabs));
152:     PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_TRUE));
153:   }
154:   PetscCall(PetscFree(queue_in_global_numbering));
155:   PetscCall(PetscViewerFlush(viewer));
156:   PetscFunctionReturn(PETSC_SUCCESS);
157: }

159: PetscErrorCode PCBDDCGraphRestoreCandidatesIS(PCBDDCGraph graph, PetscInt *n_faces, IS *FacesIS[], PetscInt *n_edges, IS *EdgesIS[], IS *VerticesIS)
160: {
161:   PetscInt       i;
162:   PetscContainer gcand;

164:   PetscFunctionBegin;
165:   PetscCall(PetscObjectQuery((PetscObject)graph->l2gmap, "_PCBDDCGraphCandidatesIS", (PetscObject *)&gcand));
166:   if (gcand) {
167:     if (n_faces) *n_faces = 0;
168:     if (n_edges) *n_edges = 0;
169:     if (FacesIS) *FacesIS = NULL;
170:     if (EdgesIS) *EdgesIS = NULL;
171:     if (VerticesIS) *VerticesIS = NULL;
172:   }
173:   if (n_faces) {
174:     if (FacesIS) {
175:       for (i = 0; i < *n_faces; i++) PetscCall(ISDestroy(&(*FacesIS)[i]));
176:       PetscCall(PetscFree(*FacesIS));
177:     }
178:     *n_faces = 0;
179:   }
180:   if (n_edges) {
181:     if (EdgesIS) {
182:       for (i = 0; i < *n_edges; i++) PetscCall(ISDestroy(&(*EdgesIS)[i]));
183:       PetscCall(PetscFree(*EdgesIS));
184:     }
185:     *n_edges = 0;
186:   }
187:   if (VerticesIS) PetscCall(ISDestroy(VerticesIS));
188:   PetscFunctionReturn(PETSC_SUCCESS);
189: }

191: PetscErrorCode PCBDDCGraphGetCandidatesIS(PCBDDCGraph graph, PetscInt *n_faces, IS *FacesIS[], PetscInt *n_edges, IS *EdgesIS[], IS *VerticesIS)
192: {
193:   IS            *ISForFaces, *ISForEdges, ISForVertices;
194:   PetscInt       i, nfc, nec, nvc, *idx, *mark;
195:   PetscContainer gcand;

197:   PetscFunctionBegin;
198:   PetscCall(PetscObjectQuery((PetscObject)graph->l2gmap, "_PCBDDCGraphCandidatesIS", (PetscObject *)&gcand));
199:   if (gcand) {
200:     PCBDDCGraphCandidates cand;

202:     PetscCall(PetscContainerGetPointer(gcand, (void **)&cand));
203:     if (n_faces) *n_faces = cand->nfc;
204:     if (FacesIS) *FacesIS = cand->Faces;
205:     if (n_edges) *n_edges = cand->nec;
206:     if (EdgesIS) *EdgesIS = cand->Edges;
207:     if (VerticesIS) *VerticesIS = cand->Vertices;
208:     PetscFunctionReturn(PETSC_SUCCESS);
209:   }
210:   PetscCall(PetscCalloc1(graph->ncc, &mark));
211:   /* loop on ccs to evaluate number of faces, edges and vertices */
212:   nfc = 0;
213:   nec = 0;
214:   nvc = 0;
215:   for (i = 0; i < graph->ncc; i++) {
216:     PetscInt repdof = graph->queue[graph->cptr[i]];
217:     if (graph->cptr[i + 1] - graph->cptr[i] > graph->custom_minimal_size && graph->nodes[repdof].count <= graph->maxcount) {
218:       if (!graph->twodim && graph->nodes[repdof].count == 2 && graph->nodes[repdof].special_dof != PCBDDCGRAPH_NEUMANN_MARK) {
219:         nfc++;
220:         mark[i] = 2;
221:       } else {
222:         nec++;
223:         mark[i] = 1;
224:       }
225:     } else {
226:       nvc += graph->cptr[i + 1] - graph->cptr[i];
227:     }
228:   }

230:   /* allocate IS arrays for faces, edges. Vertices need a single index set. */
231:   if (FacesIS) PetscCall(PetscMalloc1(nfc, &ISForFaces));
232:   if (EdgesIS) PetscCall(PetscMalloc1(nec, &ISForEdges));
233:   if (VerticesIS) PetscCall(PetscMalloc1(nvc, &idx));

235:   /* loop on ccs to compute index sets for faces and edges */
236:   if (!graph->queue_sorted) {
237:     PetscInt *queue_global;

239:     PetscCall(PetscMalloc1(graph->cptr[graph->ncc], &queue_global));
240:     PetscCall(ISLocalToGlobalMappingApply(graph->l2gmap, graph->cptr[graph->ncc], graph->queue, queue_global));
241:     for (i = 0; i < graph->ncc; i++) PetscCall(PetscSortIntWithArray(graph->cptr[i + 1] - graph->cptr[i], &queue_global[graph->cptr[i]], &graph->queue[graph->cptr[i]]));
242:     PetscCall(PetscFree(queue_global));
243:     graph->queue_sorted = PETSC_TRUE;
244:   }
245:   nfc = 0;
246:   nec = 0;
247:   for (i = 0; i < graph->ncc; i++) {
248:     if (mark[i] == 2) {
249:       if (FacesIS) PetscCall(ISCreateGeneral(PETSC_COMM_SELF, graph->cptr[i + 1] - graph->cptr[i], &graph->queue[graph->cptr[i]], PETSC_USE_POINTER, &ISForFaces[nfc]));
250:       nfc++;
251:     } else if (mark[i] == 1) {
252:       if (EdgesIS) PetscCall(ISCreateGeneral(PETSC_COMM_SELF, graph->cptr[i + 1] - graph->cptr[i], &graph->queue[graph->cptr[i]], PETSC_USE_POINTER, &ISForEdges[nec]));
253:       nec++;
254:     }
255:   }

257:   /* index set for vertices */
258:   if (VerticesIS) {
259:     nvc = 0;
260:     for (i = 0; i < graph->ncc; i++) {
261:       if (!mark[i]) {
262:         PetscInt j;

264:         for (j = graph->cptr[i]; j < graph->cptr[i + 1]; j++) {
265:           idx[nvc] = graph->queue[j];
266:           nvc++;
267:         }
268:       }
269:     }
270:     /* sort vertex set (by local ordering) */
271:     PetscCall(PetscSortInt(nvc, idx));
272:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, nvc, idx, PETSC_OWN_POINTER, &ISForVertices));
273:   }
274:   PetscCall(PetscFree(mark));

276:   /* get back info */
277:   if (n_faces) *n_faces = nfc;
278:   if (FacesIS) *FacesIS = ISForFaces;
279:   if (n_edges) *n_edges = nec;
280:   if (EdgesIS) *EdgesIS = ISForEdges;
281:   if (VerticesIS) *VerticesIS = ISForVertices;
282:   PetscFunctionReturn(PETSC_SUCCESS);
283: }

285: PetscErrorCode PCBDDCGraphComputeConnectedComponents(PCBDDCGraph graph)
286: {
287:   PetscBool adapt_interface;
288:   MPI_Comm  interface_comm;
289:   PetscBT   cornerp = NULL;

291:   PetscFunctionBegin;
292:   PetscCall(PetscObjectGetComm((PetscObject)graph->l2gmap, &interface_comm));
293:   /* compute connected components locally */
294:   PetscCall(PCBDDCGraphComputeConnectedComponentsLocal(graph));
295:   if (graph->seq_graph) PetscFunctionReturn(PETSC_SUCCESS);

297:   if (graph->active_coords && !graph->multi_element) { /* face based corner selection XXX multi_element */
298:     PetscBT    excluded;
299:     PetscReal *wdist;
300:     PetscInt   n_neigh, *neigh, *n_shared, **shared;
301:     PetscInt   maxc, ns;

303:     PetscCall(PetscBTCreate(graph->nvtxs, &cornerp));
304:     PetscCall(ISLocalToGlobalMappingGetInfo(graph->l2gmap, &n_neigh, &neigh, &n_shared, &shared));
305:     for (ns = 1, maxc = 0; ns < n_neigh; ns++) maxc = PetscMax(maxc, n_shared[ns]);
306:     PetscCall(PetscMalloc1(maxc * graph->cdim, &wdist));
307:     PetscCall(PetscBTCreate(maxc, &excluded));

309:     for (ns = 1; ns < n_neigh; ns++) { /* first proc is self */
310:       PetscReal *anchor, mdist;
311:       PetscInt   fst, j, k, d, cdim = graph->cdim, n = n_shared[ns];
312:       PetscInt   point1, point2, point3, point4;

314:       /* import coordinates on shared interface */
315:       PetscCall(PetscBTMemzero(n, excluded));
316:       for (j = 0, fst = -1, k = 0; j < n; j++) {
317:         PetscBool skip = PETSC_FALSE;
318:         for (d = 0; d < cdim; d++) {
319:           PetscReal c = graph->coords[shared[ns][j] * cdim + d];
320:           skip        = (PetscBool)(skip || c == PETSC_MAX_REAL);
321:           wdist[k++]  = c;
322:         }
323:         if (skip) PetscCall(PetscBTSet(excluded, j));
324:         else if (fst == -1) fst = j;
325:       }
326:       if (fst == -1) continue;

328:       /* the dofs are sorted by global numbering, so each rank starts from the same id
329:          and it will detect the same corners from the given set */

331:       /* find the farthest point from the starting one */
332:       anchor = wdist + fst * cdim;
333:       mdist  = -1.0;
334:       point1 = fst;
335:       for (j = fst; j < n; j++) {
336:         PetscReal dist = 0.0;

338:         if (PetscUnlikely(PetscBTLookup(excluded, j))) continue;
339:         for (d = 0; d < cdim; d++) dist += (wdist[j * cdim + d] - anchor[d]) * (wdist[j * cdim + d] - anchor[d]);
340:         if (dist > mdist) {
341:           mdist  = dist;
342:           point1 = j;
343:         }
344:       }

346:       /* find the farthest point from point1 */
347:       anchor = wdist + point1 * cdim;
348:       mdist  = -1.0;
349:       point2 = point1;
350:       for (j = fst; j < n; j++) {
351:         PetscReal dist = 0.0;

353:         if (PetscUnlikely(PetscBTLookup(excluded, j))) continue;
354:         for (d = 0; d < cdim; d++) dist += (wdist[j * cdim + d] - anchor[d]) * (wdist[j * cdim + d] - anchor[d]);
355:         if (dist > mdist) {
356:           mdist  = dist;
357:           point2 = j;
358:         }
359:       }

361:       /* find the third point maximizing the triangle area */
362:       point3 = point2;
363:       if (cdim > 2) {
364:         PetscReal a = 0.0;

366:         for (d = 0; d < cdim; d++) a += (wdist[point1 * cdim + d] - wdist[point2 * cdim + d]) * (wdist[point1 * cdim + d] - wdist[point2 * cdim + d]);
367:         a     = PetscSqrtReal(a);
368:         mdist = -1.0;
369:         for (j = fst; j < n; j++) {
370:           PetscReal area, b = 0.0, c = 0.0, s;

372:           if (PetscUnlikely(PetscBTLookup(excluded, j))) continue;
373:           for (d = 0; d < cdim; d++) {
374:             b += (wdist[point1 * cdim + d] - wdist[j * cdim + d]) * (wdist[point1 * cdim + d] - wdist[j * cdim + d]);
375:             c += (wdist[point2 * cdim + d] - wdist[j * cdim + d]) * (wdist[point2 * cdim + d] - wdist[j * cdim + d]);
376:           }
377:           b = PetscSqrtReal(b);
378:           c = PetscSqrtReal(c);
379:           s = 0.5 * (a + b + c);

381:           /* Heron's formula, area squared */
382:           area = s * (s - a) * (s - b) * (s - c);
383:           if (area > mdist) {
384:             mdist  = area;
385:             point3 = j;
386:           }
387:         }
388:       }

390:       /* find the farthest point from point3 different from point1 and point2 */
391:       anchor = wdist + point3 * cdim;
392:       mdist  = -1.0;
393:       point4 = point3;
394:       for (j = fst; j < n; j++) {
395:         PetscReal dist = 0.0;

397:         if (PetscUnlikely(PetscBTLookup(excluded, j)) || j == point1 || j == point2 || j == point3) continue;
398:         for (d = 0; d < cdim; d++) dist += (wdist[j * cdim + d] - anchor[d]) * (wdist[j * cdim + d] - anchor[d]);
399:         if (dist > mdist) {
400:           mdist  = dist;
401:           point4 = j;
402:         }
403:       }

405:       PetscCall(PetscBTSet(cornerp, shared[ns][point1]));
406:       PetscCall(PetscBTSet(cornerp, shared[ns][point2]));
407:       PetscCall(PetscBTSet(cornerp, shared[ns][point3]));
408:       PetscCall(PetscBTSet(cornerp, shared[ns][point4]));

410:       /* all dofs having the same coordinates will be primal */
411:       for (j = fst; j < n; j++) {
412:         PetscBool same[] = {PETSC_TRUE, PETSC_TRUE, PETSC_TRUE, PETSC_TRUE};

414:         if (PetscUnlikely(PetscBTLookup(excluded, j))) continue;
415:         for (d = 0; d < cdim; d++) {
416:           same[0] = (PetscBool)(same[0] && (PetscAbsReal(wdist[j * cdim + d] - wdist[point1 * cdim + d]) < PETSC_SMALL));
417:           same[1] = (PetscBool)(same[1] && (PetscAbsReal(wdist[j * cdim + d] - wdist[point2 * cdim + d]) < PETSC_SMALL));
418:           same[2] = (PetscBool)(same[2] && (PetscAbsReal(wdist[j * cdim + d] - wdist[point3 * cdim + d]) < PETSC_SMALL));
419:           same[3] = (PetscBool)(same[3] && (PetscAbsReal(wdist[j * cdim + d] - wdist[point4 * cdim + d]) < PETSC_SMALL));
420:         }
421:         if (same[0] || same[1] || same[2] || same[3]) PetscCall(PetscBTSet(cornerp, shared[ns][j]));
422:       }
423:     }
424:     PetscCall(PetscBTDestroy(&excluded));
425:     PetscCall(PetscFree(wdist));
426:     PetscCall(ISLocalToGlobalMappingRestoreInfo(graph->l2gmap, &n_neigh, &neigh, &n_shared, &shared));
427:   }

429:   /* Adapt connected components if needed */
430:   adapt_interface = (cornerp || graph->multi_element) ? PETSC_TRUE : PETSC_FALSE;
431:   for (PetscInt i = 0; i < graph->n_subsets && !adapt_interface; i++) {
432:     if (graph->subset_ncc[i] > 1) adapt_interface = PETSC_TRUE;
433:   }
434:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &adapt_interface, 1, MPI_C_BOOL, MPI_LOR, interface_comm));
435:   if (adapt_interface) {
436:     PetscSF         msf;
437:     const PetscInt *n_ref_sharing;
438:     PetscInt       *labels, *rootlabels, *mrlabels;
439:     PetscInt        nr, nmr, nrs, ncc, cum_queue;

441:     PetscCall(PetscMalloc1(graph->nvtxs, &labels));
442:     PetscCall(PetscArrayzero(labels, graph->nvtxs));
443:     for (PetscInt i = 0, k = 0; i < graph->ncc; i++) {
444:       PetscInt s = 1;
445:       for (PetscInt j = graph->cptr[i]; j < graph->cptr[i + 1]; j++) {
446:         if (cornerp && PetscBTLookup(cornerp, graph->queue[j])) {
447:           labels[graph->queue[j]] = -(k + s + 1);
448:           s += 1;
449:         } else {
450:           labels[graph->queue[j]] = -(k + 1);
451:         }
452:       }
453:       k += s;
454:     }
455:     PetscCall(PetscSFGetGraph(graph->interface_ref_sf, &nr, NULL, NULL, NULL));
456:     PetscCall(PetscSFGetGraph(graph->interface_subset_sf, &nrs, NULL, NULL, NULL));
457:     PetscCall(PetscSFGetMultiSF(graph->interface_subset_sf, &msf));
458:     PetscCall(PetscSFGetGraph(msf, &nmr, NULL, NULL, NULL));
459:     PetscCall(PetscCalloc2(nmr, &mrlabels, nrs, &rootlabels));

461:     PetscCall(PetscSFComputeDegreeBegin(graph->interface_subset_sf, &n_ref_sharing));
462:     PetscCall(PetscSFComputeDegreeEnd(graph->interface_subset_sf, &n_ref_sharing));
463:     PetscCall(PetscSFGatherBegin(graph->interface_subset_sf, MPIU_INT, labels, mrlabels));
464:     PetscCall(PetscSFGatherEnd(graph->interface_subset_sf, MPIU_INT, labels, mrlabels));

466:     /* analyze contributions from processes
467:        The structure of mrlabels is suitable to find intersections of ccs.
468:        supposing the root subset has dimension 5 and leaves with labels:
469:          0: [4 4 7 4 7], (2 connected components)
470:          1: [3 2 2 3 2], (2 connected components)
471:          2: [1 1 6 5 6], (3 connected components)
472:        the multiroot data and the new labels corresponding to intersected connected components will be (column major)

474:                   4 4 7 4 7
475:        mrlabels   3 2 2 3 2
476:                   1 1 6 5 6
477:                   ---------
478:        rootlabels 0 1 2 3 2
479:     */
480:     for (PetscInt i = 0, rcumlabels = 0, mcumlabels = 0; i < nr; i++) {
481:       const PetscInt  subset_size    = graph->interface_ref_rsize[i];
482:       const PetscInt *n_sharing      = n_ref_sharing + rcumlabels;
483:       const PetscInt *mrbuffer       = mrlabels + mcumlabels;
484:       PetscInt       *rbuffer        = rootlabels + rcumlabels;
485:       PetscInt        subset_counter = 0;

487:       for (PetscInt j = 0; j < subset_size; j++) {
488:         if (!rbuffer[j]) { /* found a new cc  */
489:           const PetscInt *jlabels = mrbuffer + j * n_sharing[0];
490:           rbuffer[j]              = ++subset_counter;

492:           for (PetscInt k = j + 1; k < subset_size; k++) { /* check for other nodes in new cc */
493:             PetscBool       same_set = PETSC_TRUE;
494:             const PetscInt *klabels  = mrbuffer + k * n_sharing[0];

496:             for (PetscInt s = 0; s < n_sharing[0]; s++) {
497:               if (jlabels[s] != klabels[s]) {
498:                 same_set = PETSC_FALSE;
499:                 break;
500:               }
501:             }
502:             if (same_set) rbuffer[k] = subset_counter;
503:           }
504:         }
505:       }
506:       if (subset_size) {
507:         rcumlabels += subset_size;
508:         mcumlabels += n_sharing[0] * subset_size;
509:       }
510:     }

512:     /* Now communicate the intersected labels */
513:     PetscCall(PetscSFBcastBegin(graph->interface_subset_sf, MPIU_INT, rootlabels, labels, MPI_REPLACE));
514:     PetscCall(PetscSFBcastEnd(graph->interface_subset_sf, MPIU_INT, rootlabels, labels, MPI_REPLACE));
515:     PetscCall(PetscFree2(mrlabels, rootlabels));

517:     /* and adapt local connected components */
518:     PetscInt  *ocptr, *oqueue;
519:     PetscBool *touched;

521:     PetscCall(PetscMalloc3(graph->ncc + 1, &ocptr, graph->cptr[graph->ncc], &oqueue, graph->cptr[graph->ncc], &touched));
522:     PetscCall(PetscArraycpy(ocptr, graph->cptr, graph->ncc + 1));
523:     PetscCall(PetscArraycpy(oqueue, graph->queue, graph->cptr[graph->ncc]));
524:     PetscCall(PetscArrayzero(touched, graph->cptr[graph->ncc]));

526:     ncc       = 0;
527:     cum_queue = 0;
528:     for (PetscInt i = 0; i < graph->ncc; i++) {
529:       for (PetscInt j = ocptr[i]; j < ocptr[i + 1]; j++) {
530:         const PetscInt jlabel = labels[oqueue[j]];

532:         if (jlabel) {
533:           graph->cptr[ncc] = cum_queue;
534:           ncc++;
535:           for (PetscInt k = j; k < ocptr[i + 1]; k++) { /* check for other nodes in new cc */
536:             if (labels[oqueue[k]] == jlabel) {
537:               graph->queue[cum_queue++] = oqueue[k];
538:               labels[oqueue[k]]         = 0;
539:             }
540:           }
541:         }
542:       }
543:     }
544:     PetscCall(PetscFree3(ocptr, oqueue, touched));
545:     PetscCall(PetscFree(labels));
546:     graph->cptr[ncc]    = cum_queue;
547:     graph->queue_sorted = PETSC_FALSE;
548:     graph->ncc          = ncc;
549:   }
550:   PetscCall(PetscBTDestroy(&cornerp));

552:   /* Determine if we are in 2D or 3D */
553:   if (!graph->twodimset) {
554:     PetscBool twodim = PETSC_TRUE;
555:     for (PetscInt i = 0; i < graph->ncc; i++) {
556:       PetscInt repdof = graph->queue[graph->cptr[i]];
557:       PetscInt ccsize = graph->cptr[i + 1] - graph->cptr[i];
558:       if (graph->nodes[repdof].count > 2 && ccsize > graph->custom_minimal_size) {
559:         twodim = PETSC_FALSE;
560:         break;
561:       }
562:     }
563:     PetscCallMPI(MPIU_Allreduce(&twodim, &graph->twodim, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)graph->l2gmap)));
564:     graph->twodimset = PETSC_TRUE;
565:   }
566:   PetscFunctionReturn(PETSC_SUCCESS);
567: }

569: static inline PetscErrorCode PCBDDCGraphComputeCC_Private(PCBDDCGraph graph, PetscInt pid, PetscInt *PETSC_RESTRICT queue_tip, PetscInt n_prev, PetscInt *n_added)
570: {
571:   PetscInt i, j, n = 0;

573:   const PetscInt *PETSC_RESTRICT xadj        = graph->xadj;
574:   const PetscInt *PETSC_RESTRICT adjncy      = graph->adjncy;
575:   const PetscInt *PETSC_RESTRICT subset_idxs = graph->subset_idxs[pid - 1];
576:   const PetscInt *PETSC_RESTRICT local_subs  = graph->local_subs;
577:   const PetscInt                 subset_size = graph->subset_size[pid - 1];

579:   PCBDDCGraphNode *PETSC_RESTRICT nodes = graph->nodes;

581:   const PetscBool havecsr  = (PetscBool)(!!xadj);
582:   const PetscBool havesubs = (PetscBool)(!!graph->n_local_subs);

584:   PetscFunctionBegin;
585:   if (havecsr && !havesubs) {
586:     for (i = -n_prev; i < 0; i++) {
587:       const PetscInt start_dof = queue_tip[i];

589:       /* we assume that if a dof has a size 1 adjacency list and the corresponding entry is negative, it is connected to all dofs */
590:       if (xadj[start_dof + 1] - xadj[start_dof] == 1 && adjncy[xadj[start_dof]] < 0) {
591:         for (j = 0; j < subset_size; j++) { /* pid \in [1,graph->n_subsets] */
592:           const PetscInt dof = subset_idxs[j];

594:           if (!nodes[dof].touched && nodes[dof].subset == pid) {
595:             nodes[dof].touched = PETSC_TRUE;
596:             queue_tip[n]       = dof;
597:             n++;
598:           }
599:         }
600:       } else {
601:         for (j = xadj[start_dof]; j < xadj[start_dof + 1]; j++) {
602:           const PetscInt dof = adjncy[j];

604:           if (!nodes[dof].touched && nodes[dof].subset == pid) {
605:             nodes[dof].touched = PETSC_TRUE;
606:             queue_tip[n]       = dof;
607:             n++;
608:           }
609:         }
610:       }
611:     }
612:   } else if (havecsr && havesubs) {
613:     const PetscInt sid = local_subs[queue_tip[-n_prev]];

615:     for (i = -n_prev; i < 0; i++) {
616:       const PetscInt start_dof = queue_tip[i];

618:       /* we assume that if a dof has a size 1 adjacency list and the corresponding entry is negative, it is connected to all dofs belonging to the local sub */
619:       if (xadj[start_dof + 1] - xadj[start_dof] == 1 && adjncy[xadj[start_dof]] < 0) {
620:         for (j = 0; j < subset_size; j++) { /* pid \in [1,graph->n_subsets] */
621:           const PetscInt dof = subset_idxs[j];

623:           if (!nodes[dof].touched && nodes[dof].subset == pid && local_subs[dof] == sid) {
624:             nodes[dof].touched = PETSC_TRUE;
625:             queue_tip[n]       = dof;
626:             n++;
627:           }
628:         }
629:       } else {
630:         for (j = xadj[start_dof]; j < xadj[start_dof + 1]; j++) {
631:           const PetscInt dof = adjncy[j];

633:           if (!nodes[dof].touched && nodes[dof].subset == pid && local_subs[dof] == sid) {
634:             nodes[dof].touched = PETSC_TRUE;
635:             queue_tip[n]       = dof;
636:             n++;
637:           }
638:         }
639:       }
640:     }
641:   } else if (havesubs) { /* sub info only */
642:     const PetscInt sid = local_subs[queue_tip[-n_prev]];

644:     for (j = 0; j < subset_size; j++) { /* pid \in [1,graph->n_subsets] */
645:       const PetscInt dof = subset_idxs[j];

647:       if (!nodes[dof].touched && nodes[dof].subset == pid && local_subs[dof] == sid) {
648:         nodes[dof].touched = PETSC_TRUE;
649:         queue_tip[n]       = dof;
650:         n++;
651:       }
652:     }
653:   } else {
654:     for (j = 0; j < subset_size; j++) { /* pid \in [1,graph->n_subsets] */
655:       const PetscInt dof = subset_idxs[j];

657:       if (!nodes[dof].touched && nodes[dof].subset == pid) {
658:         nodes[dof].touched = PETSC_TRUE;
659:         queue_tip[n]       = dof;
660:         n++;
661:       }
662:     }
663:   }
664:   *n_added = n;
665:   PetscFunctionReturn(PETSC_SUCCESS);
666: }

668: PetscErrorCode PCBDDCGraphComputeConnectedComponentsLocal(PCBDDCGraph graph)
669: {
670:   PetscInt ncc, cum_queue;

672:   PetscFunctionBegin;
673:   PetscCheck(graph->setupcalled, PetscObjectComm((PetscObject)graph->l2gmap), PETSC_ERR_ORDER, "PCBDDCGraphSetUp should be called first");
674:   /* quiet return if there isn't any local info */
675:   if (!graph->xadj && !graph->n_local_subs) PetscFunctionReturn(PETSC_SUCCESS);

677:   /* reset any previous search of connected components */
678:   for (PetscInt i = 0; i < graph->nvtxs; i++) graph->nodes[i].touched = PETSC_FALSE;
679:   if (!graph->seq_graph) {
680:     for (PetscInt i = 0; i < graph->nvtxs; i++) {
681:       if (graph->nodes[i].special_dof == PCBDDCGRAPH_DIRICHLET_MARK || graph->nodes[i].count < 2) graph->nodes[i].touched = PETSC_TRUE;
682:     }
683:   }

685:   /* begin search for connected components */
686:   cum_queue = 0;
687:   ncc       = 0;
688:   for (PetscInt n = 0; n < graph->n_subsets; n++) {
689:     const PetscInt *subset_idxs = graph->subset_idxs[n];
690:     const PetscInt  pid         = n + 1; /* partition labeled by 0 is discarded */

692:     PetscInt found = 0, prev = 0, first = 0, ncc_pid = 0;

694:     while (found != graph->subset_size[n]) {
695:       PetscInt added = 0;

697:       if (!prev) { /* search for new starting dof */
698:         while (graph->nodes[subset_idxs[first]].touched) first++;
699:         graph->nodes[subset_idxs[first]].touched = PETSC_TRUE;
700:         graph->queue[cum_queue]                  = subset_idxs[first];
701:         graph->cptr[ncc]                         = cum_queue;
702:         prev                                     = 1;
703:         cum_queue++;
704:         found++;
705:         ncc_pid++;
706:         ncc++;
707:       }
708:       PetscCall(PCBDDCGraphComputeCC_Private(graph, pid, graph->queue + cum_queue, prev, &added));
709:       if (!added) {
710:         graph->subset_ncc[n] = ncc_pid;
711:         graph->cptr[ncc]     = cum_queue;
712:       }
713:       prev = added;
714:       found += added;
715:       cum_queue += added;
716:       if (added && found == graph->subset_size[n]) {
717:         graph->subset_ncc[n] = ncc_pid;
718:         graph->cptr[ncc]     = cum_queue;
719:       }
720:     }
721:   }
722:   graph->ncc          = ncc;
723:   graph->queue_sorted = PETSC_FALSE;
724:   PetscFunctionReturn(PETSC_SUCCESS);
725: }

727: PetscErrorCode PCBDDCGraphSetUp(PCBDDCGraph graph, PetscInt custom_minimal_size, IS neumann_is, IS dirichlet_is, PetscInt n_ISForDofs, IS ISForDofs[], IS custom_primal_vertices)
728: {
729:   IS                       subset;
730:   MPI_Comm                 comm;
731:   PetscHMapPCBDDCGraphNode subsetmaps;
732:   const PetscInt          *is_indices;
733:   PetscInt                *queue_global, *nodecount, **nodeneighs, *subset_sizes;
734:   PetscInt                 i, j, k, nodes_touched, is_size, nvtxs = graph->nvtxs;
735:   PetscMPIInt              size, rank;

737:   PetscFunctionBegin;
739:   if (neumann_is) {
741:     PetscCheckSameComm(graph->l2gmap, 1, neumann_is, 3);
742:   }
743:   graph->has_dirichlet = PETSC_FALSE;
744:   if (dirichlet_is) {
746:     PetscCheckSameComm(graph->l2gmap, 1, dirichlet_is, 4);
747:     graph->has_dirichlet = PETSC_TRUE;
748:   }
750:   for (i = 0; i < n_ISForDofs; i++) {
752:     PetscCheckSameComm(graph->l2gmap, 1, ISForDofs[i], 6);
753:   }
754:   if (custom_primal_vertices) {
756:     PetscCheckSameComm(graph->l2gmap, 1, custom_primal_vertices, 7);
757:   }
758:   for (i = 0; i < nvtxs; i++) graph->nodes[i].touched = PETSC_FALSE;

760:   PetscCall(PetscObjectGetComm((PetscObject)graph->l2gmap, &comm));
761:   PetscCallMPI(MPI_Comm_size(comm, &size));
762:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

764:   /* custom_minimal_size */
765:   graph->custom_minimal_size = custom_minimal_size;

767:   /* get node info from l2gmap */
768:   PetscCall(ISLocalToGlobalMappingGetNodeInfo(graph->l2gmap, NULL, &nodecount, &nodeneighs));

770:   /* Allocate space for storing the set of neighbours for each node */
771:   graph->multi_element = PETSC_FALSE;
772:   for (i = 0; i < nvtxs; i++) {
773:     graph->nodes[i].count = nodecount[i];
774:     if (!graph->seq_graph) {
775:       PetscCall(PetscMalloc1(nodecount[i], &graph->nodes[i].neighbours_set));
776:       PetscCall(PetscArraycpy(graph->nodes[i].neighbours_set, nodeneighs[i], nodecount[i]));

778:       if (!graph->multi_element) {
779:         PetscInt nself;
780:         for (j = 0, nself = 0; j < graph->nodes[i].count; j++)
781:           if (graph->nodes[i].neighbours_set[j] == rank) nself++;
782:         if (nself > 1) graph->multi_element = PETSC_TRUE;
783:       }
784:     } else {
785:       PetscCall(PetscCalloc1(nodecount[i], &graph->nodes[i].neighbours_set));
786:     }
787:   }
788:   PetscCall(ISLocalToGlobalMappingRestoreNodeInfo(graph->l2gmap, NULL, &nodecount, &nodeneighs));
789:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &graph->multi_element, 1, MPI_C_BOOL, MPI_LOR, comm));

791:   /* compute local groups */
792:   if (graph->multi_element) {
793:     const PetscInt *idxs, *indegree;
794:     IS              is, lis;
795:     PetscLayout     layout;
796:     PetscSF         sf, multisf;
797:     PetscInt        n, nmulti, c, *multi_root_subs, *start;

799:     PetscCheck(!nvtxs || graph->local_subs, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Missing local subdomain information");

801:     PetscCall(ISLocalToGlobalMappingGetIndices(graph->l2gmap, &idxs));
802:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, nvtxs, idxs, PETSC_USE_POINTER, &is));
803:     PetscCall(ISRenumber(is, NULL, &n, &lis));
804:     PetscCall(ISDestroy(&is));

806:     PetscCall(ISLocalToGlobalMappingRestoreIndices(graph->l2gmap, &idxs));
807:     PetscCall(ISGetIndices(lis, &idxs));
808:     PetscCall(PetscLayoutCreate(PETSC_COMM_SELF, &layout));
809:     PetscCall(PetscLayoutSetSize(layout, n));
810:     PetscCall(PetscSFCreate(PETSC_COMM_SELF, &sf));
811:     PetscCall(PetscSFSetGraphLayout(sf, layout, nvtxs, NULL, PETSC_OWN_POINTER, idxs));
812:     PetscCall(PetscLayoutDestroy(&layout));
813:     PetscCall(PetscSFGetMultiSF(sf, &multisf));
814:     PetscCall(PetscSFComputeDegreeBegin(sf, &indegree));
815:     PetscCall(PetscSFComputeDegreeEnd(sf, &indegree));
816:     PetscCall(PetscSFGetGraph(multisf, &nmulti, NULL, NULL, NULL));
817:     PetscCall(PetscMalloc2(nmulti, &multi_root_subs, n + 1, &start));
818:     start[0] = 0;
819:     for (i = 0; i < n; i++) start[i + 1] = start[i] + indegree[i];
820:     PetscCall(PetscSFGatherBegin(sf, MPIU_INT, graph->local_subs, multi_root_subs));
821:     PetscCall(PetscSFGatherEnd(sf, MPIU_INT, graph->local_subs, multi_root_subs));
822:     for (i = 0; i < nvtxs; i++) {
823:       PetscInt gid = idxs[i];

825:       graph->nodes[i].local_sub = graph->local_subs[i];
826:       for (j = 0, c = 0; j < graph->nodes[i].count; j++) {
827:         if (graph->nodes[i].neighbours_set[j] == rank) c++;
828:       }
829:       PetscCheck(c == indegree[idxs[i]], PETSC_COMM_SELF, PETSC_ERR_PLIB, "%" PetscInt_FMT " != %" PetscInt_FMT, c, indegree[idxs[i]]);
830:       PetscCall(PetscMalloc1(c, &graph->nodes[i].local_groups));
831:       for (j = 0; j < c; j++) graph->nodes[i].local_groups[j] = multi_root_subs[start[gid] + j];
832:       PetscCall(PetscSortInt(c, graph->nodes[i].local_groups));
833:       graph->nodes[i].local_groups_count = c;
834:     }
835:     PetscCall(PetscFree2(multi_root_subs, start));
836:     PetscCall(ISRestoreIndices(lis, &idxs));
837:     PetscCall(ISDestroy(&lis));
838:     PetscCall(PetscSFDestroy(&sf));
839:   }

841:   /*
842:      Get info for dofs splitting
843:      User can specify just a subset; an additional field is considered as a complementary field
844:   */
845:   for (i = 0, k = 0; i < n_ISForDofs; i++) {
846:     PetscInt bs;

848:     PetscCall(ISGetBlockSize(ISForDofs[i], &bs));
849:     k += bs;
850:   }
851:   for (i = 0; i < nvtxs; i++) graph->nodes[i].which_dof = k; /* by default a dof belongs to the complement set */
852:   for (i = 0, k = 0; i < n_ISForDofs; i++) {
853:     PetscInt bs;

855:     PetscCall(ISGetLocalSize(ISForDofs[i], &is_size));
856:     PetscCall(ISGetBlockSize(ISForDofs[i], &bs));
857:     PetscCall(ISGetIndices(ISForDofs[i], &is_indices));
858:     for (j = 0; j < is_size / bs; j++) {
859:       PetscInt b;

861:       for (b = 0; b < bs; b++) {
862:         PetscInt jj = bs * j + b;

864:         if (is_indices[jj] > -1 && is_indices[jj] < nvtxs) { /* out of bounds indices (if any) are skipped */
865:           graph->nodes[is_indices[jj]].which_dof = k + b;
866:         }
867:       }
868:     }
869:     PetscCall(ISRestoreIndices(ISForDofs[i], &is_indices));
870:     k += bs;
871:   }

873:   /* Take into account Neumann nodes */
874:   if (neumann_is) {
875:     PetscCall(ISGetLocalSize(neumann_is, &is_size));
876:     PetscCall(ISGetIndices(neumann_is, &is_indices));
877:     for (i = 0; i < is_size; i++) {
878:       if (is_indices[i] > -1 && is_indices[i] < nvtxs) { /* out of bounds indices (if any) are skipped */
879:         graph->nodes[is_indices[i]].special_dof = PCBDDCGRAPH_NEUMANN_MARK;
880:       }
881:     }
882:     PetscCall(ISRestoreIndices(neumann_is, &is_indices));
883:   }

885:   /* Take into account Dirichlet nodes (they overwrite any mark previously set) */
886:   if (dirichlet_is) {
887:     PetscCall(ISGetLocalSize(dirichlet_is, &is_size));
888:     PetscCall(ISGetIndices(dirichlet_is, &is_indices));
889:     for (i = 0; i < is_size; i++) {
890:       if (is_indices[i] > -1 && is_indices[i] < nvtxs) { /* out of bounds indices (if any) are skipped */
891:         if (!graph->seq_graph) {                         /* dirichlet nodes treated as internal */
892:           graph->nodes[is_indices[i]].touched = PETSC_TRUE;
893:           graph->nodes[is_indices[i]].subset  = 0;
894:         }
895:         graph->nodes[is_indices[i]].special_dof = PCBDDCGRAPH_DIRICHLET_MARK;
896:       }
897:     }
898:     PetscCall(ISRestoreIndices(dirichlet_is, &is_indices));
899:   }

901:   /* mark special nodes (if any) -> each will become a single dof equivalence class (i.e. point constraint for BDDC) */
902:   if (custom_primal_vertices) {
903:     PetscCall(ISGetLocalSize(custom_primal_vertices, &is_size));
904:     PetscCall(ISGetIndices(custom_primal_vertices, &is_indices));
905:     for (i = 0, j = 0; i < is_size; i++) {
906:       if (is_indices[i] > -1 && is_indices[i] < nvtxs && graph->nodes[is_indices[i]].special_dof != PCBDDCGRAPH_DIRICHLET_MARK) { /* out of bounds indices (if any) are skipped */
907:         graph->nodes[is_indices[i]].special_dof = PCBDDCGRAPH_SPECIAL_MARK - j;
908:         j++;
909:       }
910:     }
911:     PetscCall(ISRestoreIndices(custom_primal_vertices, &is_indices));
912:   }

914:   /* mark interior nodes as touched and belonging to partition number 0 */
915:   if (!graph->seq_graph) {
916:     for (i = 0; i < nvtxs; i++) {
917:       const PetscInt icount = graph->nodes[i].count;
918:       if (graph->nodes[i].count < 2) {
919:         graph->nodes[i].touched = PETSC_TRUE;
920:         graph->nodes[i].subset  = 0;
921:       } else {
922:         if (graph->multi_element) {
923:           graph->nodes[i].shared = PETSC_FALSE;
924:           for (k = 0; k < icount; k++)
925:             if (graph->nodes[i].neighbours_set[k] != rank) {
926:               graph->nodes[i].shared = PETSC_TRUE;
927:               break;
928:             }
929:         } else {
930:           graph->nodes[i].shared = PETSC_TRUE;
931:         }
932:       }
933:     }
934:   } else {
935:     for (i = 0; i < nvtxs; i++) graph->nodes[i].shared = PETSC_TRUE;
936:   }

938:   /* init graph structure and compute default subsets */
939:   nodes_touched = 0;
940:   for (i = 0; i < nvtxs; i++)
941:     if (graph->nodes[i].touched) nodes_touched++;

943:   /* allocated space for queues */
944:   if (graph->seq_graph) {
945:     PetscCall(PetscMalloc2(nvtxs + 1, &graph->cptr, nvtxs, &graph->queue));
946:   } else {
947:     PetscInt nused = nvtxs - nodes_touched;
948:     PetscCall(PetscMalloc2(nused + 1, &graph->cptr, nused, &graph->queue));
949:   }

951:   graph->ncc = 0;
952:   PetscCall(PetscHMapPCBDDCGraphNodeCreate(&subsetmaps));
953:   PetscCall(PetscCalloc1(nvtxs, &subset_sizes));
954:   for (i = 0; i < nvtxs; i++) {
955:     PetscHashIter iter;
956:     PetscBool     missing;
957:     PetscInt      subset;

959:     if (graph->nodes[i].touched) continue;
960:     graph->nodes[i].touched = PETSC_TRUE;
961:     PetscCall(PetscHMapPCBDDCGraphNodePut(subsetmaps, &graph->nodes[i], &iter, &missing));
962:     if (missing) {
963:       graph->ncc++;
964:       PetscCall(PetscHMapPCBDDCGraphNodeIterSet(subsetmaps, iter, graph->ncc));
965:       subset = graph->ncc;
966:     } else PetscCall(PetscHMapPCBDDCGraphNodeIterGet(subsetmaps, iter, &subset));
967:     subset_sizes[subset - 1] += 1;
968:     graph->nodes[i].subset = subset;
969:   }

971:   graph->cptr[0] = 0;
972:   for (i = 0; i < graph->ncc; i++) graph->cptr[i + 1] = graph->cptr[i] + subset_sizes[i];
973:   for (i = 0; i < graph->ncc; i++) subset_sizes[i] = 0;

975:   for (i = 0; i < nvtxs; i++) {
976:     const PetscInt subset = graph->nodes[i].subset - 1;
977:     if (subset < 0) continue;
978:     PetscCheck(subset_sizes[subset] + graph->cptr[subset] < graph->cptr[subset + 1], PETSC_COMM_SELF, PETSC_ERR_PLIB, "Error for subset %" PetscInt_FMT, subset);
979:     graph->queue[subset_sizes[subset] + graph->cptr[subset]] = i;
980:     subset_sizes[subset] += 1;
981:   }
982:   for (i = 0; i < graph->ncc; i++) PetscCheck(subset_sizes[i] + graph->cptr[i] == graph->cptr[i + 1], PETSC_COMM_SELF, PETSC_ERR_PLIB, "Error for subset %" PetscInt_FMT, i);

984:   PetscCall(PetscHMapPCBDDCGraphNodeDestroy(&subsetmaps));
985:   PetscCall(PetscFree(subset_sizes));

987:   /* set default number of subsets */
988:   graph->n_subsets = graph->ncc;
989:   PetscCall(PetscMalloc1(graph->n_subsets, &graph->subset_ncc));
990:   for (i = 0; i < graph->n_subsets; i++) graph->subset_ncc[i] = 1;

992:   PetscCall(PetscMalloc1(graph->ncc, &graph->subset_ref_node));
993:   PetscCall(PetscMalloc1(graph->cptr[graph->ncc], &queue_global));
994:   PetscCall(PetscMalloc2(graph->ncc, &graph->subset_size, graph->ncc, &graph->subset_idxs));
995:   if (graph->multi_element) PetscCall(PetscMalloc1(graph->ncc, &graph->gsubset_size));
996:   else graph->gsubset_size = graph->subset_size;
997:   PetscCall(ISLocalToGlobalMappingApply(graph->l2gmap, graph->cptr[graph->ncc], graph->queue, queue_global));

999:   PetscHMapI cnt_unique;

1001:   PetscCall(PetscHMapICreate(&cnt_unique));
1002:   for (j = 0; j < graph->ncc; j++) {
1003:     PetscInt c = 0, ref_node = PETSC_INT_MAX;

1005:     for (k = graph->cptr[j]; k < graph->cptr[j + 1]; k++) {
1006:       ref_node = PetscMin(ref_node, queue_global[k]);
1007:       if (graph->multi_element) {
1008:         PetscBool     missing;
1009:         PetscHashIter iter;

1011:         PetscCall(PetscHMapIPut(cnt_unique, queue_global[k], &iter, &missing));
1012:         if (missing) c++;
1013:       }
1014:     }
1015:     graph->gsubset_size[j]    = c;
1016:     graph->subset_size[j]     = graph->cptr[j + 1] - graph->cptr[j];
1017:     graph->subset_ref_node[j] = ref_node;
1018:     if (graph->multi_element) PetscCall(PetscHMapIClear(cnt_unique));
1019:   }
1020:   PetscCall(PetscHMapIDestroy(&cnt_unique));

1022:   /* save information on subsets (needed when analyzing the connected components) */
1023:   if (graph->ncc) {
1024:     PetscCall(PetscMalloc1(graph->cptr[graph->ncc], &graph->subset_idxs[0]));
1025:     PetscCall(PetscArrayzero(graph->subset_idxs[0], graph->cptr[graph->ncc]));
1026:     for (j = 1; j < graph->ncc; j++) graph->subset_idxs[j] = graph->subset_idxs[j - 1] + graph->subset_size[j - 1];
1027:     PetscCall(PetscArraycpy(graph->subset_idxs[0], graph->queue, graph->cptr[graph->ncc]));
1028:   }

1030:   /* check consistency and create SF to analyze components on the interface between subdomains */
1031:   if (!graph->seq_graph) {
1032:     PetscSF         msf;
1033:     PetscLayout     map;
1034:     const PetscInt *degree;
1035:     PetscInt        nr, nmr, *rdata;
1036:     PetscBool       valid = PETSC_TRUE;
1037:     PetscInt        subset_N;
1038:     IS              subset_n;
1039:     const PetscInt *idxs;

1041:     PetscCall(ISCreateGeneral(comm, graph->n_subsets, graph->subset_ref_node, PETSC_USE_POINTER, &subset));
1042:     PetscCall(ISRenumber(subset, NULL, &subset_N, &subset_n));
1043:     PetscCall(ISDestroy(&subset));

1045:     PetscCall(PetscSFCreate(comm, &graph->interface_ref_sf));
1046:     PetscCall(PetscLayoutCreateFromSizes(comm, PETSC_DECIDE, subset_N, 1, &map));
1047:     PetscCall(ISGetIndices(subset_n, &idxs));
1048:     PetscCall(PetscSFSetGraphLayout(graph->interface_ref_sf, map, graph->n_subsets, NULL, PETSC_OWN_POINTER, idxs));
1049:     PetscCall(ISRestoreIndices(subset_n, &idxs));
1050:     PetscCall(ISDestroy(&subset_n));
1051:     PetscCall(PetscLayoutDestroy(&map));

1053:     PetscCall(PetscSFComputeDegreeBegin(graph->interface_ref_sf, &degree));
1054:     PetscCall(PetscSFComputeDegreeEnd(graph->interface_ref_sf, &degree));
1055:     PetscCall(PetscSFGetMultiSF(graph->interface_ref_sf, &msf));
1056:     PetscCall(PetscSFGetGraph(graph->interface_ref_sf, &nr, NULL, NULL, NULL));
1057:     PetscCall(PetscSFGetGraph(msf, &nmr, NULL, NULL, NULL));
1058:     PetscCall(PetscCalloc1(nmr, &rdata));
1059:     PetscCall(PetscSFGatherBegin(graph->interface_ref_sf, MPIU_INT, graph->gsubset_size, rdata));
1060:     PetscCall(PetscSFGatherEnd(graph->interface_ref_sf, MPIU_INT, graph->gsubset_size, rdata));
1061:     for (PetscInt i = 0, c = 0; i < nr && valid; i++) {
1062:       for (PetscInt j = 0; j < degree[i]; j++) {
1063:         if (rdata[j + c] != rdata[c]) valid = PETSC_FALSE;
1064:       }
1065:       c += degree[i];
1066:     }
1067:     PetscCall(PetscFree(rdata));
1068:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &valid, 1, MPI_C_BOOL, MPI_LAND, comm));
1069:     PetscCheck(valid, comm, PETSC_ERR_PLIB, "Initial local subsets are not consistent");

1071:     /* Now create SF with each root extended to gsubset_size roots */
1072:     PetscInt           mss = 0;
1073:     const PetscSFNode *subs_remote;

1075:     PetscCall(PetscSFGetGraph(graph->interface_ref_sf, NULL, NULL, NULL, &subs_remote));
1076:     for (PetscInt i = 0; i < graph->n_subsets; i++) mss = PetscMax(graph->subset_size[i], mss);

1078:     PetscInt nri, nli, *start_rsize, *cum_rsize;
1079:     PetscCall(PetscCalloc1(graph->n_subsets + 1, &start_rsize));
1080:     PetscCall(PetscCalloc1(nr, &graph->interface_ref_rsize));
1081:     PetscCall(PetscMalloc1(nr + 1, &cum_rsize));
1082:     PetscCall(PetscSFReduceBegin(graph->interface_ref_sf, MPIU_INT, graph->gsubset_size, graph->interface_ref_rsize, MPI_REPLACE));
1083:     PetscCall(PetscSFReduceEnd(graph->interface_ref_sf, MPIU_INT, graph->gsubset_size, graph->interface_ref_rsize, MPI_REPLACE));

1085:     nri          = 0;
1086:     cum_rsize[0] = 0;
1087:     for (PetscInt i = 0; i < nr; i++) {
1088:       nri += graph->interface_ref_rsize[i];
1089:       cum_rsize[i + 1] = cum_rsize[i] + graph->interface_ref_rsize[i];
1090:     }
1091:     nli = graph->cptr[graph->ncc];
1092:     PetscCall(PetscSFBcastBegin(graph->interface_ref_sf, MPIU_INT, cum_rsize, start_rsize, MPI_REPLACE));
1093:     PetscCall(PetscSFBcastEnd(graph->interface_ref_sf, MPIU_INT, cum_rsize, start_rsize, MPI_REPLACE));
1094:     PetscCall(PetscFree(cum_rsize));

1096:     PetscInt    *ilocal, *queue_global_uniq;
1097:     PetscSFNode *iremote;
1098:     PetscBool   *touched;

1100:     PetscCall(PetscSFCreate(comm, &graph->interface_subset_sf));
1101:     PetscCall(PetscMalloc1(nli, &ilocal));
1102:     PetscCall(PetscMalloc1(nli, &iremote));
1103:     PetscCall(PetscMalloc2(mss, &queue_global_uniq, mss, &touched));
1104:     for (PetscInt i = 0, nli = 0; i < graph->n_subsets; i++) {
1105:       const PetscMPIInt rr                = (PetscMPIInt)subs_remote[i].rank;
1106:       const PetscInt    start             = start_rsize[i];
1107:       const PetscInt    subset_size       = graph->subset_size[i];
1108:       const PetscInt    gsubset_size      = graph->gsubset_size[i];
1109:       const PetscInt   *subset_idxs       = graph->subset_idxs[i];
1110:       const PetscInt   *lsub_queue_global = queue_global + graph->cptr[i];

1112:       k = subset_size;
1113:       PetscCall(PetscArrayzero(touched, subset_size));
1114:       PetscCall(PetscArraycpy(queue_global_uniq, lsub_queue_global, subset_size));
1115:       PetscCall(PetscSortRemoveDupsInt(&k, queue_global_uniq));
1116:       PetscCheck(k == gsubset_size, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Invalid local subset %" PetscInt_FMT " size %" PetscInt_FMT " != %" PetscInt_FMT, i, k, gsubset_size);

1118:       PetscInt t = 0, j = 0;
1119:       while (t < subset_size) {
1120:         while (j < subset_size && touched[j]) j++;
1121:         PetscCheck(j < subset_size, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Unexpected %" PetscInt_FMT " >= %" PetscInt_FMT, j, subset_size);
1122:         const PetscInt ls = graph->nodes[subset_idxs[j]].local_sub;

1124:         for (k = j; k < subset_size; k++) {
1125:           if (graph->nodes[subset_idxs[k]].local_sub == ls) {
1126:             PetscInt ig;

1128:             PetscCall(PetscFindInt(lsub_queue_global[k], gsubset_size, queue_global_uniq, &ig));
1129:             ilocal[nli]        = subset_idxs[k];
1130:             iremote[nli].rank  = rr;
1131:             iremote[nli].index = start + ig;
1132:             touched[k]         = PETSC_TRUE;
1133:             nli++;
1134:             t++;
1135:           }
1136:         }
1137:       }
1138:     }
1139:     PetscCheck(nli == graph->cptr[graph->ncc], PETSC_COMM_SELF, PETSC_ERR_PLIB, "Invalid ilocal size %" PetscInt_FMT " != %" PetscInt_FMT, nli, graph->cptr[graph->ncc]);
1140:     PetscCall(PetscSFSetGraph(graph->interface_subset_sf, nri, nli, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
1141:     PetscCall(PetscFree(start_rsize));
1142:     PetscCall(PetscFree2(queue_global_uniq, touched));
1143:   }
1144:   PetscCall(PetscFree(queue_global));

1146:   /* free workspace */
1147:   graph->setupcalled = PETSC_TRUE;
1148:   PetscFunctionReturn(PETSC_SUCCESS);
1149: }

1151: PetscErrorCode PCBDDCGraphResetCoords(PCBDDCGraph graph)
1152: {
1153:   PetscFunctionBegin;
1154:   if (!graph) PetscFunctionReturn(PETSC_SUCCESS);
1155:   PetscCall(PetscFree(graph->coords));
1156:   graph->cdim  = 0;
1157:   graph->cnloc = 0;
1158:   graph->cloc  = PETSC_FALSE;
1159:   PetscFunctionReturn(PETSC_SUCCESS);
1160: }

1162: PetscErrorCode PCBDDCGraphResetCSR(PCBDDCGraph graph)
1163: {
1164:   PetscFunctionBegin;
1165:   if (!graph) PetscFunctionReturn(PETSC_SUCCESS);
1166:   if (graph->freecsr) {
1167:     PetscCall(PetscFree(graph->xadj));
1168:     PetscCall(PetscFree(graph->adjncy));
1169:   } else {
1170:     graph->xadj   = NULL;
1171:     graph->adjncy = NULL;
1172:   }
1173:   graph->freecsr   = PETSC_FALSE;
1174:   graph->nvtxs_csr = 0;
1175:   PetscFunctionReturn(PETSC_SUCCESS);
1176: }

1178: PetscErrorCode PCBDDCGraphReset(PCBDDCGraph graph)
1179: {
1180:   PetscFunctionBegin;
1181:   if (!graph) PetscFunctionReturn(PETSC_SUCCESS);
1182:   PetscCall(ISLocalToGlobalMappingDestroy(&graph->l2gmap));
1183:   PetscCall(PetscFree(graph->subset_ncc));
1184:   PetscCall(PetscFree(graph->subset_ref_node));
1185:   for (PetscInt i = 0; i < graph->nvtxs; i++) {
1186:     PetscCall(PetscFree(graph->nodes[i].neighbours_set));
1187:     PetscCall(PetscFree(graph->nodes[i].local_groups));
1188:   }
1189:   PetscCall(PetscFree(graph->nodes));
1190:   PetscCall(PetscFree2(graph->cptr, graph->queue));
1191:   if (graph->subset_idxs) PetscCall(PetscFree(graph->subset_idxs[0]));
1192:   PetscCall(PetscFree2(graph->subset_size, graph->subset_idxs));
1193:   if (graph->multi_element) PetscCall(PetscFree(graph->gsubset_size));
1194:   PetscCall(PetscFree(graph->interface_ref_rsize));
1195:   PetscCall(PetscSFDestroy(&graph->interface_subset_sf));
1196:   PetscCall(PetscSFDestroy(&graph->interface_ref_sf));
1197:   PetscCall(ISDestroy(&graph->dirdofs));
1198:   PetscCall(ISDestroy(&graph->dirdofsB));
1199:   if (graph->n_local_subs) PetscCall(PetscFree(graph->local_subs));
1200:   graph->multi_element       = PETSC_FALSE;
1201:   graph->has_dirichlet       = PETSC_FALSE;
1202:   graph->twodimset           = PETSC_FALSE;
1203:   graph->twodim              = PETSC_FALSE;
1204:   graph->nvtxs               = 0;
1205:   graph->nvtxs_global        = 0;
1206:   graph->n_subsets           = 0;
1207:   graph->custom_minimal_size = 1;
1208:   graph->n_local_subs        = 0;
1209:   graph->maxcount            = PETSC_INT_MAX;
1210:   graph->seq_graph           = PETSC_FALSE;
1211:   graph->setupcalled         = PETSC_FALSE;
1212:   PetscFunctionReturn(PETSC_SUCCESS);
1213: }

1215: PetscErrorCode PCBDDCGraphInit(PCBDDCGraph graph, ISLocalToGlobalMapping l2gmap, PetscInt N, PetscInt maxcount)
1216: {
1217:   PetscInt n;

1219:   PetscFunctionBegin;
1220:   PetscAssertPointer(graph, 1);
1224:   /* raise an error if already allocated */
1225:   PetscCheck(!graph->nvtxs_global, PetscObjectComm((PetscObject)l2gmap), PETSC_ERR_PLIB, "BDDCGraph already initialized");
1226:   /* set number of vertices */
1227:   PetscCall(PetscObjectReference((PetscObject)l2gmap));
1228:   graph->l2gmap = l2gmap;
1229:   PetscCall(ISLocalToGlobalMappingGetSize(l2gmap, &n));
1230:   graph->nvtxs        = n;
1231:   graph->nvtxs_global = N;
1232:   /* allocate used space */
1233:   PetscCall(PetscCalloc1(graph->nvtxs, &graph->nodes));
1234:   /* use -1 as a default value for which_dof array */
1235:   for (n = 0; n < graph->nvtxs; n++) graph->nodes[n].which_dof = -1;

1237:   /* zeroes workspace for values of ncc */
1238:   graph->subset_ncc      = NULL;
1239:   graph->subset_ref_node = NULL;
1240:   /* maxcount for cc */
1241:   graph->maxcount = maxcount;
1242:   PetscFunctionReturn(PETSC_SUCCESS);
1243: }

1245: PetscErrorCode PCBDDCGraphDestroy(PCBDDCGraph *graph)
1246: {
1247:   PetscFunctionBegin;
1248:   PetscCall(PCBDDCGraphResetCSR(*graph));
1249:   PetscCall(PCBDDCGraphResetCoords(*graph));
1250:   PetscCall(PCBDDCGraphReset(*graph));
1251:   PetscCall(PetscFree(*graph));
1252:   PetscFunctionReturn(PETSC_SUCCESS);
1253: }

1255: PetscErrorCode PCBDDCGraphCreate(PCBDDCGraph *graph)
1256: {
1257:   PCBDDCGraph new_graph;

1259:   PetscFunctionBegin;
1260:   PetscCall(PetscNew(&new_graph));
1261:   new_graph->custom_minimal_size = 1;
1262:   *graph                         = new_graph;
1263:   PetscFunctionReturn(PETSC_SUCCESS);
1264: }