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: /* defines MatSetValues_MPI_Hash(), MatAssemblyBegin_MPI_Hash(), and MatAssemblyEnd_MPI_Hash() */
 10: #define TYPE AIJ
 11: #define TYPE_AIJ
 12: #include "../src/mat/impls/aij/mpi/mpihashmat.h"
 13: #undef TYPE
 14: #undef TYPE_AIJ

 16: static PetscErrorCode MatReset_MPIAIJ(Mat mat)
 17: {
 18:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

 20:   PetscFunctionBegin;
 21:   PetscCall(PetscLogObjectState((PetscObject)mat, "Rows=%" PetscInt_FMT ", Cols=%" PetscInt_FMT, mat->rmap->N, mat->cmap->N));
 22:   PetscCall(MatStashDestroy_Private(&mat->stash));
 23:   PetscCall(VecDestroy(&aij->diag));
 24:   PetscCall(MatDestroy(&aij->A));
 25:   PetscCall(MatDestroy(&aij->B));
 26: #if PetscDefined(USE_CTABLE)
 27:   PetscCall(PetscHMapIDestroy(&aij->colmap));
 28: #else
 29:   PetscCall(PetscFree(aij->colmap));
 30: #endif
 31:   PetscCall(PetscFree(aij->garray));
 32:   PetscCall(VecDestroy(&aij->lvec));
 33:   PetscCall(VecScatterDestroy(&aij->Mvctx));
 34:   PetscCall(PetscFree2(aij->rowvalues, aij->rowindices));
 35:   PetscCall(PetscFree(aij->ld));
 36:   PetscFunctionReturn(PETSC_SUCCESS);
 37: }

 39: static PetscErrorCode MatResetHash_MPIAIJ(Mat mat)
 40: {
 41:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
 42:   /* Save the nonzero states of the component matrices because those are what are used to determine
 43:     the nonzero state of mat */
 44:   PetscObjectState Astate = aij->A->nonzerostate, Bstate = aij->B->nonzerostate;

 46:   PetscFunctionBegin;
 47:   PetscCall(MatReset_MPIAIJ(mat));
 48:   PetscCall(MatSetUp_MPI_Hash(mat));
 49:   aij->A->nonzerostate = ++Astate, aij->B->nonzerostate = ++Bstate;
 50:   PetscFunctionReturn(PETSC_SUCCESS);
 51: }

 53: PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
 54: {
 55:   PetscFunctionBegin;
 56:   PetscCall(MatReset_MPIAIJ(mat));

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

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

 63:   PetscCall(PetscObjectChangeTypeName((PetscObject)mat, NULL));
 64:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatStoreValues_C", NULL));
 65:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatRetrieveValues_C", NULL));
 66:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatGetMultPetscSF_C", NULL));
 67:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatIsTranspose_C", NULL));
 68:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocation_C", NULL));
 69:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetPreallocation_C", NULL));
 70:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetHash_C", NULL));
 71:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocationCSR_C", NULL));
 72:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatDiagonalScaleLocal_C", NULL));
 73:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpibaij_C", NULL));
 74:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisbaij_C", NULL));
 75: #if PetscDefined(HAVE_CUDA)
 76:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcusparse_C", NULL));
 77: #endif
 78: #if PetscDefined(HAVE_HIP)
 79:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijhipsparse_C", NULL));
 80: #endif
 81: #if PetscDefined(HAVE_KOKKOS_KERNELS)
 82:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijkokkos_C", NULL));
 83: #endif
 84:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpidense_C", NULL));
 85: #if PetscDefined(HAVE_ELEMENTAL)
 86:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_elemental_C", NULL));
 87: #endif
 88: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
 89:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_scalapack_C", NULL));
 90: #endif
 91: #if PetscDefined(HAVE_HYPRE)
 92:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_hypre_C", NULL));
 93:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", NULL));
 94: #endif
 95:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 96:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_is_mpiaij_C", NULL));
 97:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_mpiaij_mpiaij_C", NULL));
 98:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetUseScalableIncreaseOverlap_C", NULL));
 99:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijperm_C", NULL));
100:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijsell_C", NULL));
101: #if PetscDefined(HAVE_MKL_SPARSE)
102:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijmkl_C", NULL));
103: #endif
104:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcrl_C", NULL));
105:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
106:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisell_C", NULL));
107:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetPreallocationCOO_C", NULL));
108:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetValuesCOO_C", NULL));
109:   PetscFunctionReturn(PETSC_SUCCESS);
110: }

112: static PetscErrorCode MatGetRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
113: {
114:   Mat B;

116:   PetscFunctionBegin;
117:   PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, &B));
118:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject)B));
119:   PetscCall(MatGetRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
120:   PetscCall(MatDestroy(&B));
121:   PetscFunctionReturn(PETSC_SUCCESS);
122: }

124: static PetscErrorCode MatRestoreRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
125: {
126:   Mat B;

128:   PetscFunctionBegin;
129:   PetscCall(PetscObjectQuery((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject *)&B));
130:   PetscCall(MatRestoreRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
131:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", NULL));
132:   PetscFunctionReturn(PETSC_SUCCESS);
133: }

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

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

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

147:   Level: beginner

149: .seealso: [](ch_matrices), `Mat`, `MatCreateMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`, `MATSEQAIJ`, `MATMPIAIJ`, `MATAIJ`
150: M*/

152: static PetscErrorCode MatBindToCPU_MPIAIJ(Mat A, PetscBool flg)
153: {
154:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

156:   PetscFunctionBegin;
157: #if PetscDefined(HAVE_CUDA) || PetscDefined(HAVE_HIP) || PetscDefined(HAVE_VIENNACL)
158:   A->boundtocpu = flg;
159: #endif
160:   if (a->A) PetscCall(MatBindToCPU(a->A, flg));
161:   if (a->B) PetscCall(MatBindToCPU(a->B, flg));

163:   /* In addition to binding the diagonal and off-diagonal matrices, bind the local vectors used for matrix-vector products.
164:    * This maybe seems a little odd for a MatBindToCPU() call to do, but it makes no sense for the binding of these vectors
165:    * to differ from the parent matrix. */
166:   if (a->lvec) PetscCall(VecBindToCPU(a->lvec, flg));
167:   if (a->diag) PetscCall(VecBindToCPU(a->diag, flg));
168:   PetscFunctionReturn(PETSC_SUCCESS);
169: }

171: static PetscErrorCode MatSetBlockSizes_MPIAIJ(Mat M, PetscInt rbs, PetscInt cbs)
172: {
173:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)M->data;

175:   PetscFunctionBegin;
176:   if (mat->A) {
177:     PetscCall(MatSetBlockSizes(mat->A, rbs, cbs));
178:     PetscCall(MatSetBlockSizes(mat->B, rbs, 1));
179:   }
180:   PetscFunctionReturn(PETSC_SUCCESS);
181: }

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

193:   PetscFunctionBegin;
194:   *keptrows = NULL;

196:   ia = a->i;
197:   ib = b->i;
198:   PetscCall(MatSeqAIJGetArrayRead(mat->A, &aav));
199:   PetscCall(MatSeqAIJGetArrayRead(mat->B, &bav));
200:   for (i = 0; i < m; i++) {
201:     na = ia[i + 1] - ia[i];
202:     nb = ib[i + 1] - ib[i];
203:     if (!na && !nb) {
204:       cnt++;
205:       goto ok1;
206:     }
207:     aa = aav + ia[i];
208:     for (j = 0; j < na; j++) {
209:       if (aa[j] != 0.0) goto ok1;
210:     }
211:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
212:     for (j = 0; j < nb; j++) {
213:       if (bb[j] != 0.0) goto ok1;
214:     }
215:     cnt++;
216:   ok1:;
217:   }
218:   PetscCallMPI(MPIU_Allreduce(&cnt, &n0rows, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)M)));
219:   if (!n0rows) {
220:     PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
221:     PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
222:     PetscFunctionReturn(PETSC_SUCCESS);
223:   }
224:   PetscCall(PetscMalloc1(M->rmap->n - cnt, &rows));
225:   cnt = 0;
226:   for (i = 0; i < m; i++) {
227:     na = ia[i + 1] - ia[i];
228:     nb = ib[i + 1] - ib[i];
229:     if (!na && !nb) continue;
230:     aa = aav + ia[i];
231:     for (j = 0; j < na; j++) {
232:       if (aa[j] != 0.0) {
233:         rows[cnt++] = rstart + i;
234:         goto ok2;
235:       }
236:     }
237:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
238:     for (j = 0; j < nb; j++) {
239:       if (bb[j] != 0.0) {
240:         rows[cnt++] = rstart + i;
241:         goto ok2;
242:       }
243:     }
244:   ok2:;
245:   }
246:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), cnt, rows, PETSC_OWN_POINTER, keptrows));
247:   PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
248:   PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
249:   PetscFunctionReturn(PETSC_SUCCESS);
250: }

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

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

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

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

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

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

319: static PetscErrorCode MatFindOffBlockDiagonalEntries_MPIAIJ(Mat A, IS *is)
320: {
321:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
322:   IS              sis, gis;
323:   const PetscInt *isis, *igis;
324:   PetscInt        n, *iis, nsis, ngis, rstart, i;

326:   PetscFunctionBegin;
327:   PetscCall(MatFindOffBlockDiagonalEntries(a->A, &sis));
328:   PetscCall(MatFindNonzeroRows(a->B, &gis));
329:   PetscCall(ISGetSize(gis, &ngis));
330:   PetscCall(ISGetSize(sis, &nsis));
331:   PetscCall(ISGetIndices(sis, &isis));
332:   PetscCall(ISGetIndices(gis, &igis));

334:   PetscCall(PetscMalloc1(ngis + nsis, &iis));
335:   PetscCall(PetscArraycpy(iis, igis, ngis));
336:   PetscCall(PetscArraycpy(iis + ngis, isis, nsis));
337:   n = ngis + nsis;
338:   PetscCall(PetscSortRemoveDupsInt(&n, iis));
339:   PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
340:   for (i = 0; i < n; i++) iis[i] += rstart;
341:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), n, iis, PETSC_OWN_POINTER, is));

343:   PetscCall(ISRestoreIndices(sis, &isis));
344:   PetscCall(ISRestoreIndices(gis, &igis));
345:   PetscCall(ISDestroy(&sis));
346:   PetscCall(ISDestroy(&gis));
347:   PetscFunctionReturn(PETSC_SUCCESS);
348: }

350: /*
351:   Local utility routine that creates a mapping from the global column
352: number to the local number in the off-diagonal part of the local
353: storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
354: a slightly higher hash table cost; without it it is not scalable (each processor
355: has an order N integer array but is fast to access.
356: */
357: PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
358: {
359:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
360:   PetscInt    n   = aij->B->cmap->n, i;

362:   PetscFunctionBegin;
363:   PetscCheck(!n || aij->garray, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MPIAIJ Matrix was assembled but is missing garray");
364: #if PetscDefined(USE_CTABLE)
365:   PetscCall(PetscHMapICreateWithSize(n, &aij->colmap));
366:   for (i = 0; i < n; i++) PetscCall(PetscHMapISet(aij->colmap, aij->garray[i] + 1, i + 1));
367: #else
368:   PetscCall(PetscCalloc1(mat->cmap->N + 1, &aij->colmap));
369:   for (i = 0; i < n; i++) aij->colmap[aij->garray[i]] = i + 1;
370: #endif
371:   PetscFunctionReturn(PETSC_SUCCESS);
372: }

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

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

463: static PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A, PetscInt row, const PetscScalar v[])
464: {
465:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)A->data;
466:   Mat_SeqAIJ  *a = (Mat_SeqAIJ *)mat->A->data, *b = (Mat_SeqAIJ *)mat->B->data;
467:   PetscInt     l, *garray                         = mat->garray, diag;
468:   PetscScalar *aa, *ba;

470:   PetscFunctionBegin;
471:   /* code only works for square matrices A */

473:   /* find size of row to the left of the diagonal part */
474:   PetscCall(MatGetOwnershipRange(A, &diag, NULL));
475:   row = row - diag;
476:   for (l = 0; l < b->i[row + 1] - b->i[row]; l++) {
477:     if (garray[b->j[b->i[row] + l]] > diag) break;
478:   }
479:   if (l) {
480:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
481:     PetscCall(PetscArraycpy(ba + b->i[row], v, l));
482:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
483:   }

485:   /* diagonal part */
486:   if (a->i[row + 1] - a->i[row]) {
487:     PetscCall(MatSeqAIJGetArray(mat->A, &aa));
488:     PetscCall(PetscArraycpy(aa + a->i[row], v + l, a->i[row + 1] - a->i[row]));
489:     PetscCall(MatSeqAIJRestoreArray(mat->A, &aa));
490:   }

492:   /* right of diagonal part */
493:   if (b->i[row + 1] - b->i[row] - l) {
494:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
495:     PetscCall(PetscArraycpy(ba + b->i[row] + l, v + l + a->i[row + 1] - a->i[row], b->i[row + 1] - b->i[row] - l));
496:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
497:   }
498:   PetscFunctionReturn(PETSC_SUCCESS);
499: }

501: PetscErrorCode MatSetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt im[], PetscInt n, const PetscInt in[], const PetscScalar v[], InsertMode addv)
502: {
503:   Mat_MPIAIJ *aij   = (Mat_MPIAIJ *)mat->data;
504:   PetscScalar value = 0.0;
505:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
506:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
507:   PetscBool   roworiented = aij->roworiented;

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

522:   PetscFunctionBegin;
523:   PetscCall(MatSeqAIJGetArray(A, &aa));
524:   PetscCall(MatSeqAIJGetArray(B, &ba));
525:   for (i = 0; i < m; i++) {
526:     if (im[i] < 0) continue;
527:     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);
528:     if (im[i] >= rstart && im[i] < rend) {
529:       row      = im[i] - rstart;
530:       lastcol1 = -1;
531:       rp1      = PetscSafePointerPlusOffset(aj, ai[row]);
532:       ap1      = PetscSafePointerPlusOffset(aa, ai[row]);
533:       rmax1    = aimax[row];
534:       nrow1    = ailen[row];
535:       low1     = 0;
536:       high1    = nrow1;
537:       lastcol2 = -1;
538:       rp2      = PetscSafePointerPlusOffset(bj, bi[row]);
539:       ap2      = PetscSafePointerPlusOffset(ba, bi[row]);
540:       rmax2    = bimax[row];
541:       nrow2    = bilen[row];
542:       low2     = 0;
543:       high2    = nrow2;

545:       for (j = 0; j < n; j++) {
546:         if (v) value = roworiented ? v[i * n + j] : v[i + j * m];
547:         if (ignorezeroentries && value == 0.0 && addv == ADD_VALUES && im[i] != in[j]) continue;
548:         if (in[j] >= cstart && in[j] < cend) {
549:           col   = in[j] - cstart;
550:           nonew = a->nonew;
551:           MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
552:         } else if (in[j] < 0) {
553:           continue;
554:         } else {
555:           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);
556:           if (mat->was_assembled) {
557:             if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
558: #if PetscDefined(USE_CTABLE)
559:             PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col)); /* map global col ids to local ones */
560:             col--;
561: #else
562:             col = aij->colmap[in[j]] - 1;
563: #endif
564:             if (col < 0 && !((Mat_SeqAIJ *)aij->B->data)->nonew) { /* col < 0 means in[j] is a new col for B */
565:               PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));  /* Change aij->B from reduced/local format to expanded/global format */
566:               col = in[j];
567:               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
568:               B     = aij->B;
569:               b     = (Mat_SeqAIJ *)B->data;
570:               bimax = b->imax;
571:               bi    = b->i;
572:               bilen = b->ilen;
573:               bj    = b->j;
574:               ba    = b->a;
575:               rp2   = PetscSafePointerPlusOffset(bj, bi[row]);
576:               ap2   = PetscSafePointerPlusOffset(ba, bi[row]);
577:               rmax2 = bimax[row];
578:               nrow2 = bilen[row];
579:               low2  = 0;
580:               high2 = nrow2;
581:               bm    = aij->B->rmap->n;
582:               ba    = b->a;
583:             } else if (col < 0 && !(ignorezeroentries && value == 0.0)) {
584:               PetscCheck(1 == ((Mat_SeqAIJ *)aij->B->data)->nonew, 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]);
585:               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]));
586:             }
587:           } else col = in[j];
588:           nonew = b->nonew;
589:           MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
590:         }
591:       }
592:     } else {
593:       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]);
594:       if (!aij->donotstash) {
595:         mat->assembled = PETSC_FALSE;
596:         if (roworiented) {
597:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i * n), (PetscBool)(ignorezeroentries && addv == ADD_VALUES)));
598:         } else {
599:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i), m, (PetscBool)(ignorezeroentries && addv == ADD_VALUES)));
600:         }
601:       }
602:     }
603:   }
604:   PetscCall(MatSeqAIJRestoreArray(A, &aa)); /* aa, bb might have been free'd due to reallocation above. But we don't access them here */
605:   PetscCall(MatSeqAIJRestoreArray(B, &ba));
606:   PetscFunctionReturn(PETSC_SUCCESS);
607: }

609: /*
610:     This function sets the j and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
611:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
612:     No off-processor parts off the matrix are allowed here and mat->was_assembled has to be PETSC_FALSE.
613: */
614: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat_Symbolic(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[])
615: {
616:   Mat_MPIAIJ *aij    = (Mat_MPIAIJ *)mat->data;
617:   Mat         A      = aij->A; /* diagonal part of the matrix */
618:   Mat         B      = aij->B; /* off-diagonal part of the matrix */
619:   Mat_SeqAIJ *a      = (Mat_SeqAIJ *)A->data;
620:   Mat_SeqAIJ *b      = (Mat_SeqAIJ *)B->data;
621:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, col;
622:   PetscInt   *ailen = a->ilen, *aj = a->j;
623:   PetscInt   *bilen = b->ilen, *bj = b->j;
624:   PetscInt    am          = aij->A->rmap->n, j;
625:   PetscInt    diag_so_far = 0, dnz;
626:   PetscInt    offd_so_far = 0, onz;

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

649: /*
650:     This function sets the local j, a and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
651:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
652:     No off-processor parts off the matrix are allowed here, they are set at a later point by MatSetValues_MPIAIJ.
653:     Also, mat->was_assembled has to be false, otherwise the statement aj[rowstart_diag+dnz_row] = mat_j[col] - cstart;
654:     would not be true and the more complex MatSetValues_MPIAIJ has to be used.
655: */
656: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[], const PetscScalar mat_a[])
657: {
658:   Mat_MPIAIJ  *aij  = (Mat_MPIAIJ *)mat->data;
659:   Mat          A    = aij->A; /* diagonal part of the matrix */
660:   Mat          B    = aij->B; /* off-diagonal part of the matrix */
661:   Mat_SeqAIJ  *aijd = (Mat_SeqAIJ *)aij->A->data, *aijo = (Mat_SeqAIJ *)aij->B->data;
662:   Mat_SeqAIJ  *a      = (Mat_SeqAIJ *)A->data;
663:   Mat_SeqAIJ  *b      = (Mat_SeqAIJ *)B->data;
664:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend;
665:   PetscInt    *ailen = a->ilen, *aj = a->j;
666:   PetscInt    *bilen = b->ilen, *bj = b->j;
667:   PetscInt     am          = aij->A->rmap->n, j;
668:   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. */
669:   PetscInt     col, dnz_row, onz_row, rowstart_diag, rowstart_offd;
670:   PetscScalar *aa = a->a, *ba = b->a;

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

697: static PetscErrorCode MatGetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt idxm[], PetscInt n, const PetscInt idxn[], PetscScalar v[])
698: {
699:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
700:   PetscInt     i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
701:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
702:   PetscBool    roworiented = aij->roworiented;
703:   PetscScalar *value;

705:   PetscFunctionBegin;
706:   for (i = 0; i < m; i++) {
707:     if (idxm[i] < 0) continue; /* negative row */
708:     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);
709:     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);
710:     row = idxm[i] - rstart;
711:     for (j = 0; j < n; j++) {
712:       if (idxn[j] < 0) continue; /* negative column */
713:       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);
714:       value = roworiented ? &v[j + i * n] : &v[i + j * m];
715:       if (idxn[j] >= cstart && idxn[j] < cend) {
716:         col = idxn[j] - cstart;
717:         PetscCall(MatGetValues(aij->A, 1, &row, 1, &col, value));
718:       } else {
719:         if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
720: #if PetscDefined(USE_CTABLE)
721:         PetscCall(PetscHMapIGetWithDefault(aij->colmap, idxn[j] + 1, 0, &col));
722:         col--;
723: #else
724:         col = aij->colmap[idxn[j]] - 1;
725: #endif
726:         if (col < 0 || aij->garray[col] != idxn[j]) *value = 0.0;
727:         else PetscCall(MatGetValues(aij->B, 1, &row, 1, &col, value));
728:       }
729:     }
730:   }
731:   PetscFunctionReturn(PETSC_SUCCESS);
732: }

734: static PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat, MatAssemblyType mode)
735: {
736:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
737:   PetscInt    nstash, reallocs;

739:   PetscFunctionBegin;
740:   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(PETSC_SUCCESS);

742:   PetscCall(MatStashScatterBegin_Private(mat, &mat->stash, mat->rmap->range));
743:   PetscCall(MatStashGetInfo_Private(&mat->stash, &nstash, &reallocs));
744:   PetscCall(PetscInfo(mat, "Stash has %" PetscInt_FMT " entries, uses %" PetscInt_FMT " mallocs.\n", nstash, reallocs));
745:   PetscFunctionReturn(PETSC_SUCCESS);
746: }

748: PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat, MatAssemblyType mode)
749: {
750:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
751:   PetscMPIInt  n;
752:   PetscInt     i, j, rstart, ncols, flg;
753:   PetscInt    *row, *col;
754:   PetscBool    all_assembled;
755:   PetscScalar *val;

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

759:   PetscFunctionBegin;
760:   if (!aij->donotstash && !mat->nooffprocentries) {
761:     while (1) {
762:       PetscCall(MatStashScatterGetMesg_Private(&mat->stash, &n, &row, &col, &val, &flg));
763:       if (!flg) break;

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

790:   /* determine if any process has disassembled, if so we must
791:      also disassemble ourself, in order that we may reassemble. */
792:   /*
793:      if nonzero structure of submatrix B cannot change then we know that
794:      no process disassembled thus we can skip this stuff
795:   */
796:   if (!((Mat_SeqAIJ *)aij->B->data)->nonew) {
797:     PetscCallMPI(MPIU_Allreduce(&mat->was_assembled, &all_assembled, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
798:     if (mat->was_assembled && !all_assembled) { /* mat on this rank has reduced off-diag B with local col ids, but globally it does not */
799:       PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));
800:     }
801:   }
802:   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) PetscCall(MatSetUpMultiply_MPIAIJ(mat));
803:   PetscCall(MatSetOption(aij->B, MAT_USE_INODES, PETSC_FALSE));
804: #if PetscDefined(HAVE_DEVICE)
805:   if (mat->offloadmask == PETSC_OFFLOAD_CPU && aij->B->offloadmask != PETSC_OFFLOAD_UNALLOCATED) aij->B->offloadmask = PETSC_OFFLOAD_CPU;
806: #endif
807:   PetscCall(MatAssemblyBegin(aij->B, mode));
808:   PetscCall(MatAssemblyEnd(aij->B, mode));

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

812:   aij->rowvalues = NULL;

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

816:   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
817:   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ *)aij->A->data)->nonew) {
818:     mat->nonzerostate = aij->A->nonzerostate + aij->B->nonzerostate;
819:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));
820:   }
821: #if PetscDefined(HAVE_DEVICE)
822:   mat->offloadmask = PETSC_OFFLOAD_BOTH;
823: #endif
824:   PetscFunctionReturn(PETSC_SUCCESS);
825: }

827: static PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
828: {
829:   Mat_MPIAIJ *l = (Mat_MPIAIJ *)A->data;

831:   PetscFunctionBegin;
832:   PetscCall(MatZeroEntries(l->A));
833:   PetscCall(MatZeroEntries(l->B));
834:   PetscFunctionReturn(PETSC_SUCCESS);
835: }

837: static PetscErrorCode MatZeroRows_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
838: {
839:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)A->data;
840:   PetscInt   *lrows;
841:   PetscInt    r, len;
842:   PetscBool   cong;

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

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

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

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

900:   /* only change matrix nonzero state if pattern was allowed to be changed */
901:   if (!((Mat_SeqAIJ *)mat->A->data)->keepnonzeropattern || !((Mat_SeqAIJ *)mat->A->data)->nonew) {
902:     A->nonzerostate = mat->A->nonzerostate + mat->B->nonzerostate;
903:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
904:   }
905:   PetscFunctionReturn(PETSC_SUCCESS);
906: }

908: static PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
909: {
910:   Mat_MPIAIJ        *l = (Mat_MPIAIJ *)A->data;
911:   PetscInt           n = A->rmap->n;
912:   PetscInt           i, j, r, m, len = 0;
913:   PetscInt          *lrows, *owners = A->rmap->range;
914:   PetscMPIInt        p = 0;
915:   PetscSFNode       *rrows;
916:   PetscSF            sf;
917:   const PetscScalar *xx;
918:   PetscScalar       *bb, *mask, *aij_a;
919:   Vec                xmask, lmask;
920:   Mat_SeqAIJ        *aij = (Mat_SeqAIJ *)l->B->data;
921:   const PetscInt    *aj, *ii, *ridx;
922:   PetscScalar       *aa;

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

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

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

1018:   /* only change matrix nonzero state if pattern was allowed to be changed */
1019:   if (!((Mat_SeqAIJ *)l->A->data)->nonew) {
1020:     A->nonzerostate = l->A->nonzerostate + l->B->nonzerostate;
1021:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
1022:   }
1023:   PetscFunctionReturn(PETSC_SUCCESS);
1024: }

1026: static PetscErrorCode MatMult_MPIAIJ(Mat A, Vec xx, Vec yy)
1027: {
1028:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
1029:   PetscInt    nt;
1030:   VecScatter  Mvctx = a->Mvctx;

1032:   PetscFunctionBegin;
1033:   PetscCall(VecGetLocalSize(xx, &nt));
1034:   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);
1035:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1036:   PetscUseTypeMethod(a->A, mult, xx, yy);
1037:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1038:   PetscUseTypeMethod(a->B, multadd, a->lvec, yy, yy);
1039:   PetscFunctionReturn(PETSC_SUCCESS);
1040: }

1042: static PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A, Vec bb, Vec xx)
1043: {
1044:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1046:   PetscFunctionBegin;
1047:   PetscCall(MatMultDiagonalBlock(a->A, bb, xx));
1048:   PetscFunctionReturn(PETSC_SUCCESS);
1049: }

1051: static PetscErrorCode MatMultAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1052: {
1053:   Mat_MPIAIJ *a     = (Mat_MPIAIJ *)A->data;
1054:   VecScatter  Mvctx = a->Mvctx;

1056:   PetscFunctionBegin;
1057:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1058:   PetscUseTypeMethod(a->A, multadd, xx, yy, zz);
1059:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1060:   PetscUseTypeMethod(a->B, multadd, a->lvec, zz, zz);
1061:   PetscFunctionReturn(PETSC_SUCCESS);
1062: }

1064: static PetscErrorCode MatMultTranspose_MPIAIJ(Mat A, Vec xx, Vec yy)
1065: {
1066:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1068:   PetscFunctionBegin;
1069:   /* do nondiagonal part */
1070:   PetscUseTypeMethod(a->B, multtranspose, xx, a->lvec);
1071:   /* do local part */
1072:   PetscUseTypeMethod(a->A, multtranspose, xx, yy);
1073:   /* add partial results together */
1074:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1075:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1076:   PetscFunctionReturn(PETSC_SUCCESS);
1077: }

1079: static PetscErrorCode MatIsTranspose_MPIAIJ(Mat Amat, Mat Bmat, PetscReal tol, PetscBool *f)
1080: {
1081:   MPI_Comm    comm;
1082:   Mat_MPIAIJ *Aij = (Mat_MPIAIJ *)Amat->data, *Bij = (Mat_MPIAIJ *)Bmat->data;
1083:   Mat         Adia = Aij->A, Bdia = Bij->A, Aoff, Boff, *Aoffs, *Boffs;
1084:   IS          Me, Notme;
1085:   PetscInt    M, N, first, last, *notme, i;
1086:   PetscMPIInt size;

1088:   PetscFunctionBegin;
1089:   /* Easy test: symmetric diagonal block */
1090:   PetscCall(MatIsTranspose(Adia, Bdia, tol, f));
1091:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, f, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)Amat)));
1092:   if (!*f) PetscFunctionReturn(PETSC_SUCCESS);
1093:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
1094:   PetscCallMPI(MPI_Comm_size(comm, &size));
1095:   if (size == 1) PetscFunctionReturn(PETSC_SUCCESS);

1097:   /* Hard test: off-diagonal block. This takes a MatCreateSubMatrix. */
1098:   PetscCall(MatGetSize(Amat, &M, &N));
1099:   PetscCall(MatGetOwnershipRange(Amat, &first, &last));
1100:   PetscCall(PetscMalloc1(N - last + first, &notme));
1101:   for (i = 0; i < first; i++) notme[i] = i;
1102:   for (i = last; i < M; i++) notme[i - last + first] = i;
1103:   PetscCall(ISCreateGeneral(MPI_COMM_SELF, N - last + first, notme, PETSC_COPY_VALUES, &Notme));
1104:   PetscCall(ISCreateStride(MPI_COMM_SELF, last - first, first, 1, &Me));
1105:   PetscCall(MatCreateSubMatrices(Amat, 1, &Me, &Notme, MAT_INITIAL_MATRIX, &Aoffs));
1106:   Aoff = Aoffs[0];
1107:   PetscCall(MatCreateSubMatrices(Bmat, 1, &Notme, &Me, MAT_INITIAL_MATRIX, &Boffs));
1108:   Boff = Boffs[0];
1109:   PetscCall(MatIsTranspose(Aoff, Boff, tol, f));
1110:   PetscCall(MatDestroyMatrices(1, &Aoffs));
1111:   PetscCall(MatDestroyMatrices(1, &Boffs));
1112:   PetscCall(ISDestroy(&Me));
1113:   PetscCall(ISDestroy(&Notme));
1114:   PetscCall(PetscFree(notme));
1115:   PetscFunctionReturn(PETSC_SUCCESS);
1116: }

1118: static PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1119: {
1120:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1122:   PetscFunctionBegin;
1123:   /* do nondiagonal part */
1124:   PetscUseTypeMethod(a->B, multtranspose, xx, a->lvec);
1125:   /* do local part */
1126:   PetscUseTypeMethod(a->A, multtransposeadd, xx, yy, zz);
1127:   /* add partial results together */
1128:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1129:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1130:   PetscFunctionReturn(PETSC_SUCCESS);
1131: }

1133: /*
1134:   This only works correctly for square matrices where the subblock A->A is the
1135:    diagonal block
1136: */
1137: static PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A, Vec v)
1138: {
1139:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1141:   PetscFunctionBegin;
1142:   PetscCheck(A->rmap->N == A->cmap->N, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Supports only square matrix where A->A is diag block");
1143:   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");
1144:   PetscCall(MatGetDiagonal(a->A, v));
1145:   PetscFunctionReturn(PETSC_SUCCESS);
1146: }

1148: static PetscErrorCode MatScale_MPIAIJ(Mat A, PetscScalar aa)
1149: {
1150:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1152:   PetscFunctionBegin;
1153:   PetscCall(MatScale(a->A, aa));
1154:   PetscCall(MatScale(a->B, aa));
1155:   PetscFunctionReturn(PETSC_SUCCESS);
1156: }

1158: static PetscErrorCode MatView_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
1159: {
1160:   Mat_MPIAIJ        *aij    = (Mat_MPIAIJ *)mat->data;
1161:   Mat_SeqAIJ        *A      = (Mat_SeqAIJ *)aij->A->data;
1162:   Mat_SeqAIJ        *B      = (Mat_SeqAIJ *)aij->B->data;
1163:   const PetscInt    *garray = aij->garray;
1164:   const PetscScalar *aa, *ba;
1165:   PetscInt           header[4], M, N, m, rs, cs, cnt, i, ja, jb;
1166:   PetscInt64         nz, hnz;
1167:   PetscInt          *rowlens;
1168:   PetscInt          *colidxs;
1169:   PetscScalar       *matvals;
1170:   PetscMPIInt        rank;

1172:   PetscFunctionBegin;
1173:   PetscCall(PetscViewerSetUp(viewer));

1175:   M  = mat->rmap->N;
1176:   N  = mat->cmap->N;
1177:   m  = mat->rmap->n;
1178:   rs = mat->rmap->rstart;
1179:   cs = mat->cmap->rstart;
1180:   nz = A->nz + B->nz;

1182:   /* write matrix header */
1183:   header[0] = MAT_FILE_CLASSID;
1184:   header[1] = M;
1185:   header[2] = N;
1186:   PetscCallMPI(MPI_Reduce(&nz, &hnz, 1, MPIU_INT64, MPI_SUM, 0, PetscObjectComm((PetscObject)mat)));
1187:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1188:   if (rank == 0) PetscCall(PetscIntCast(hnz, &header[3]));
1189:   PetscCall(PetscViewerBinaryWrite(viewer, header, 4, PETSC_INT));

1191:   /* fill in and store row lengths  */
1192:   PetscCall(PetscMalloc1(m, &rowlens));
1193:   for (i = 0; i < m; i++) rowlens[i] = A->i[i + 1] - A->i[i] + B->i[i + 1] - B->i[i];
1194:   PetscCall(PetscViewerBinaryWriteAll(viewer, rowlens, m, rs, M, PETSC_INT));
1195:   PetscCall(PetscFree(rowlens));

1197:   /* fill in and store column indices */
1198:   PetscCall(PetscMalloc1(nz, &colidxs));
1199:   for (cnt = 0, i = 0; i < m; i++) {
1200:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1201:       if (garray[B->j[jb]] > cs) break;
1202:       colidxs[cnt++] = garray[B->j[jb]];
1203:     }
1204:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) colidxs[cnt++] = A->j[ja] + cs;
1205:     for (; jb < B->i[i + 1]; jb++) colidxs[cnt++] = garray[B->j[jb]];
1206:   }
1207:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1208:   PetscCall(PetscViewerBinaryWriteAll(viewer, colidxs, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
1209:   PetscCall(PetscFree(colidxs));

1211:   /* fill in and store nonzero values */
1212:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &aa));
1213:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &ba));
1214:   PetscCall(PetscMalloc1(nz, &matvals));
1215:   for (cnt = 0, i = 0; i < m; i++) {
1216:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1217:       if (garray[B->j[jb]] > cs) break;
1218:       matvals[cnt++] = ba[jb];
1219:     }
1220:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) matvals[cnt++] = aa[ja];
1221:     for (; jb < B->i[i + 1]; jb++) matvals[cnt++] = ba[jb];
1222:   }
1223:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &aa));
1224:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &ba));
1225:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_LIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1226:   PetscCall(PetscViewerBinaryWriteAll(viewer, matvals, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
1227:   PetscCall(PetscFree(matvals));

1229:   /* write block size option to the viewer's .info file */
1230:   PetscCall(MatView_Binary_BlockSizes(mat, viewer));
1231:   PetscFunctionReturn(PETSC_SUCCESS);
1232: }

1234: #include <petscdraw.h>
1235: static PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat, PetscViewer viewer)
1236: {
1237:   Mat_MPIAIJ       *aij  = (Mat_MPIAIJ *)mat->data;
1238:   PetscMPIInt       rank = aij->rank, size = aij->size;
1239:   PetscBool         isdraw, isascii, isbinary;
1240:   PetscViewer       sviewer;
1241:   PetscViewerFormat format;

1243:   PetscFunctionBegin;
1244:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1245:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
1246:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1247:   if (isascii) {
1248:     PetscCall(PetscViewerGetFormat(viewer, &format));
1249:     if (format == PETSC_VIEWER_LOAD_BALANCE) {
1250:       PetscInt i, nmax = 0, nmin = PETSC_INT_MAX, navg = 0, *nz, nzlocal = ((Mat_SeqAIJ *)aij->A->data)->nz + ((Mat_SeqAIJ *)aij->B->data)->nz;
1251:       PetscCall(PetscMalloc1(size, &nz));
1252:       PetscCallMPI(MPI_Allgather(&nzlocal, 1, MPIU_INT, nz, 1, MPIU_INT, PetscObjectComm((PetscObject)mat)));
1253:       for (i = 0; i < size; i++) {
1254:         nmax = PetscMax(nmax, nz[i]);
1255:         nmin = PetscMin(nmin, nz[i]);
1256:         navg += nz[i];
1257:       }
1258:       PetscCall(PetscFree(nz));
1259:       navg = navg / size;
1260:       PetscCall(PetscViewerASCIIPrintf(viewer, "Load Balance - Nonzeros: Min %" PetscInt_FMT "  avg %" PetscInt_FMT "  max %" PetscInt_FMT "\n", nmin, navg, nmax));
1261:       PetscFunctionReturn(PETSC_SUCCESS);
1262:     }
1263:     PetscCall(PetscViewerGetFormat(viewer, &format));
1264:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1265:       MatInfo   info;
1266:       PetscInt *inodes = NULL;

1268:       PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1269:       PetscCall(MatGetInfo(mat, MAT_LOCAL, &info));
1270:       PetscCall(MatInodeGetInodeSizes(aij->A, NULL, &inodes, NULL));
1271:       PetscCall(PetscViewerASCIIPushSynchronized(viewer));
1272:       if (!inodes) {
1273:         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,
1274:                                                      info.memory));
1275:       } else {
1276:         PetscCall(
1277:           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, info.memory));
1278:       }
1279:       PetscCall(MatGetInfo(aij->A, MAT_LOCAL, &info));
1280:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] on-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1281:       PetscCall(MatGetInfo(aij->B, MAT_LOCAL, &info));
1282:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] off-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1283:       PetscCall(PetscViewerFlush(viewer));
1284:       PetscCall(PetscViewerASCIIPopSynchronized(viewer));
1285:       PetscCall(PetscViewerASCIIPrintf(viewer, "Information on VecScatter used in matrix-vector product: \n"));
1286:       PetscCall(VecScatterView(aij->Mvctx, viewer));
1287:       PetscFunctionReturn(PETSC_SUCCESS);
1288:     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1289:       PetscInt inodecount, inodelimit, *inodes;
1290:       PetscCall(MatInodeGetInodeSizes(aij->A, &inodecount, &inodes, &inodelimit));
1291:       if (inodes) {
1292:         PetscCall(PetscViewerASCIIPrintf(viewer, "using I-node (on process 0) routines: found %" PetscInt_FMT " nodes, limit used is %" PetscInt_FMT "\n", inodecount, inodelimit));
1293:       } else {
1294:         PetscCall(PetscViewerASCIIPrintf(viewer, "not using I-node (on process 0) routines\n"));
1295:       }
1296:       PetscFunctionReturn(PETSC_SUCCESS);
1297:     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1298:       PetscFunctionReturn(PETSC_SUCCESS);
1299:     }
1300:   } else if (isbinary) {
1301:     if (size == 1) {
1302:       PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1303:       PetscCall(MatView(aij->A, viewer));
1304:     } else {
1305:       PetscCall(MatView_MPIAIJ_Binary(mat, viewer));
1306:     }
1307:     PetscFunctionReturn(PETSC_SUCCESS);
1308:   } else if (isascii && size == 1) {
1309:     PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1310:     PetscCall(MatView(aij->A, viewer));
1311:     PetscFunctionReturn(PETSC_SUCCESS);
1312:   } else if (isdraw) {
1313:     PetscDraw draw;
1314:     PetscBool isnull;
1315:     PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
1316:     PetscCall(PetscDrawIsNull(draw, &isnull));
1317:     if (isnull) PetscFunctionReturn(PETSC_SUCCESS);
1318:   }

1320:   { /* assemble the entire matrix onto first processor */
1321:     Mat A = NULL, Av;
1322:     IS  isrow, iscol;

1324:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->rmap->N : 0, 0, 1, &isrow));
1325:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->cmap->N : 0, 0, 1, &iscol));
1326:     PetscCall(MatCreateSubMatrix(mat, isrow, iscol, MAT_INITIAL_MATRIX, &A));
1327:     PetscCall(MatMPIAIJGetSeqAIJ(A, &Av, NULL, NULL));
1328:     /*  The commented code uses MatCreateSubMatrices instead */
1329:     /*
1330:     Mat *AA, A = NULL, Av;
1331:     IS  isrow,iscol;

1333:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->rmap->N : 0,0,1,&isrow));
1334:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->cmap->N : 0,0,1,&iscol));
1335:     PetscCall(MatCreateSubMatrices(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&AA));
1336:     if (rank == 0) {
1337:        PetscCall(PetscObjectReference((PetscObject)AA[0]));
1338:        A    = AA[0];
1339:        Av   = AA[0];
1340:     }
1341:     PetscCall(MatDestroySubMatrices(1,&AA));
1342: */
1343:     PetscCall(ISDestroy(&iscol));
1344:     PetscCall(ISDestroy(&isrow));
1345:     /*
1346:        Everyone has to call to draw the matrix since the graphics waits are
1347:        synchronized across all processors that share the PetscDraw object
1348:     */
1349:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1350:     if (rank == 0) {
1351:       if (((PetscObject)mat)->name) PetscCall(PetscObjectSetName((PetscObject)Av, ((PetscObject)mat)->name));
1352:       PetscCall(MatView_SeqAIJ(Av, sviewer));
1353:     }
1354:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1355:     PetscCall(MatDestroy(&A));
1356:   }
1357:   PetscFunctionReturn(PETSC_SUCCESS);
1358: }

1360: PetscErrorCode MatView_MPIAIJ(Mat mat, PetscViewer viewer)
1361: {
1362:   PetscBool isascii, isdraw, issocket, isbinary;

1364:   PetscFunctionBegin;
1365:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
1366:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1367:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1368:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSOCKET, &issocket));
1369:   if (isascii || isdraw || isbinary || issocket) PetscCall(MatView_MPIAIJ_ASCIIorDraworSocket(mat, viewer));
1370:   PetscFunctionReturn(PETSC_SUCCESS);
1371: }

1373: static PetscErrorCode MatSOR_MPIAIJ(Mat matin, Vec bb, PetscReal omega, MatSORType flag, PetscReal fshift, PetscInt its, PetscInt lits, Vec xx)
1374: {
1375:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)matin->data;
1376:   Vec         bb1 = NULL;
1377:   PetscBool   hasop;

1379:   PetscFunctionBegin;
1380:   if (flag == SOR_APPLY_UPPER) {
1381:     PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1382:     PetscFunctionReturn(PETSC_SUCCESS);
1383:   }

1385:   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) PetscCall(VecDuplicate(bb, &bb1));

1387:   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1388:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1389:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1390:       its--;
1391:     }

1393:     while (its--) {
1394:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1395:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1397:       /* update rhs: bb1 = bb - B*x */
1398:       PetscCall(VecScale(mat->lvec, -1.0));
1399:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1401:       /* local sweep */
1402:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_SYMMETRIC_SWEEP, fshift, lits, 1, xx);
1403:     }
1404:   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1405:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1406:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1407:       its--;
1408:     }
1409:     while (its--) {
1410:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1411:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1413:       /* update rhs: bb1 = bb - B*x */
1414:       PetscCall(VecScale(mat->lvec, -1.0));
1415:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1417:       /* local sweep */
1418:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_FORWARD_SWEEP, fshift, lits, 1, xx);
1419:     }
1420:   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1421:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1422:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1423:       its--;
1424:     }
1425:     while (its--) {
1426:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1427:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1429:       /* update rhs: bb1 = bb - B*x */
1430:       PetscCall(VecScale(mat->lvec, -1.0));
1431:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1433:       /* local sweep */
1434:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_BACKWARD_SWEEP, fshift, lits, 1, xx);
1435:     }
1436:   } else if (flag & SOR_EISENSTAT) {
1437:     Vec xx1;

1439:     PetscCall(VecDuplicate(bb, &xx1));
1440:     PetscUseTypeMethod(mat->A, sor, bb, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP), fshift, lits, 1, xx);

1442:     PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1443:     PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1444:     if (!mat->diag) {
1445:       PetscCall(MatCreateVecs(matin, &mat->diag, NULL));
1446:       PetscCall(MatGetDiagonal(matin, mat->diag));
1447:     }
1448:     PetscCall(MatHasOperation(matin, MATOP_MULT_DIAGONAL_BLOCK, &hasop));
1449:     if (hasop) PetscCall(MatMultDiagonalBlock(matin, xx, bb1));
1450:     else PetscCall(VecPointwiseMult(bb1, mat->diag, xx));
1451:     PetscCall(VecAYPX(bb1, (omega - 2.0) / omega, bb));

1453:     PetscCall(MatMultAdd(mat->B, mat->lvec, bb1, bb1));

1455:     /* local sweep */
1456:     PetscUseTypeMethod(mat->A, sor, bb1, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP), fshift, lits, 1, xx1);
1457:     PetscCall(VecAXPY(xx, 1.0, xx1));
1458:     PetscCall(VecDestroy(&xx1));
1459:   } else SETERRQ(PetscObjectComm((PetscObject)matin), PETSC_ERR_SUP, "Parallel SOR not supported");

1461:   PetscCall(VecDestroy(&bb1));

1463:   matin->factorerrortype = mat->A->factorerrortype;
1464:   PetscFunctionReturn(PETSC_SUCCESS);
1465: }

1467: static PetscErrorCode MatPermute_MPIAIJ(Mat A, IS rowp, IS colp, Mat *B)
1468: {
1469:   Mat             aA, aB, Aperm;
1470:   const PetscInt *rwant, *cwant, *gcols, *ai, *bi, *aj, *bj;
1471:   PetscScalar    *aa, *ba;
1472:   PetscInt        i, j, m, n, ng, anz, bnz, *dnnz, *onnz, *tdnnz, *tonnz, *rdest, *cdest, *work, *gcdest;
1473:   PetscSF         rowsf, sf;
1474:   IS              parcolp = NULL;
1475:   PetscBool       done;

1477:   PetscFunctionBegin;
1478:   PetscCall(MatGetLocalSize(A, &m, &n));
1479:   PetscCall(ISGetIndices(rowp, &rwant));
1480:   PetscCall(ISGetIndices(colp, &cwant));
1481:   PetscCall(PetscMalloc3(PetscMax(m, n), &work, m, &rdest, n, &cdest));

1483:   /* Invert row permutation to find out where my rows should go */
1484:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &rowsf));
1485:   PetscCall(PetscSFSetGraphLayout(rowsf, A->rmap, A->rmap->n, NULL, PETSC_OWN_POINTER, rwant));
1486:   PetscCall(PetscSFSetFromOptions(rowsf));
1487:   for (i = 0; i < m; i++) work[i] = A->rmap->rstart + i;
1488:   PetscCall(PetscSFReduceBegin(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));
1489:   PetscCall(PetscSFReduceEnd(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));

1491:   /* Invert column permutation to find out where my columns should go */
1492:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1493:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, A->cmap->n, NULL, PETSC_OWN_POINTER, cwant));
1494:   PetscCall(PetscSFSetFromOptions(sf));
1495:   for (i = 0; i < n; i++) work[i] = A->cmap->rstart + i;
1496:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1497:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1498:   PetscCall(PetscSFDestroy(&sf));

1500:   PetscCall(ISRestoreIndices(rowp, &rwant));
1501:   PetscCall(ISRestoreIndices(colp, &cwant));
1502:   PetscCall(MatMPIAIJGetSeqAIJ(A, &aA, &aB, &gcols));

1504:   /* Find out where my gcols should go */
1505:   PetscCall(MatGetSize(aB, NULL, &ng));
1506:   PetscCall(PetscMalloc1(ng, &gcdest));
1507:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1508:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, ng, NULL, PETSC_OWN_POINTER, gcols));
1509:   PetscCall(PetscSFSetFromOptions(sf));
1510:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1511:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1512:   PetscCall(PetscSFDestroy(&sf));

1514:   PetscCall(PetscCalloc4(m, &dnnz, m, &onnz, m, &tdnnz, m, &tonnz));
1515:   PetscCall(MatGetRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1516:   PetscCall(MatGetRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1517:   for (i = 0; i < m; i++) {
1518:     PetscInt    row = rdest[i];
1519:     PetscMPIInt rowner;
1520:     PetscCall(PetscLayoutFindOwner(A->rmap, row, &rowner));
1521:     for (j = ai[i]; j < ai[i + 1]; j++) {
1522:       PetscInt    col = cdest[aj[j]];
1523:       PetscMPIInt cowner;
1524:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner)); /* Could build an index for the columns to eliminate this search */
1525:       if (rowner == cowner) dnnz[i]++;
1526:       else onnz[i]++;
1527:     }
1528:     for (j = bi[i]; j < bi[i + 1]; j++) {
1529:       PetscInt    col = gcdest[bj[j]];
1530:       PetscMPIInt cowner;
1531:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner));
1532:       if (rowner == cowner) dnnz[i]++;
1533:       else onnz[i]++;
1534:     }
1535:   }
1536:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1537:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1538:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1539:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1540:   PetscCall(PetscSFDestroy(&rowsf));

1542:   PetscCall(MatCreateAIJ(PetscObjectComm((PetscObject)A), A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N, 0, tdnnz, 0, tonnz, &Aperm));
1543:   PetscCall(MatSeqAIJGetArray(aA, &aa));
1544:   PetscCall(MatSeqAIJGetArray(aB, &ba));
1545:   for (i = 0; i < m; i++) {
1546:     PetscInt *acols = dnnz, *bcols = onnz; /* Repurpose now-unneeded arrays */
1547:     PetscInt  rowlen;
1548:     rowlen = ai[i + 1] - ai[i];
1549:     for (PetscInt j0 = j = 0; j < rowlen; j0 = j) { /* rowlen could be larger than number of rows m, so sum in batches */
1550:       for (; j < PetscMin(rowlen, j0 + m); j++) acols[j - j0] = cdest[aj[ai[i] + j]];
1551:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, acols, aa + ai[i] + j0, INSERT_VALUES));
1552:     }
1553:     rowlen = bi[i + 1] - bi[i];
1554:     for (PetscInt j0 = j = 0; j < rowlen; j0 = j) {
1555:       for (; j < PetscMin(rowlen, j0 + m); j++) bcols[j - j0] = gcdest[bj[bi[i] + j]];
1556:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, bcols, ba + bi[i] + j0, INSERT_VALUES));
1557:     }
1558:   }
1559:   PetscCall(MatAssemblyBegin(Aperm, MAT_FINAL_ASSEMBLY));
1560:   PetscCall(MatAssemblyEnd(Aperm, MAT_FINAL_ASSEMBLY));
1561:   PetscCall(MatRestoreRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1562:   PetscCall(MatRestoreRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1563:   PetscCall(MatSeqAIJRestoreArray(aA, &aa));
1564:   PetscCall(MatSeqAIJRestoreArray(aB, &ba));
1565:   PetscCall(PetscFree4(dnnz, onnz, tdnnz, tonnz));
1566:   PetscCall(PetscFree3(work, rdest, cdest));
1567:   PetscCall(PetscFree(gcdest));
1568:   if (parcolp) PetscCall(ISDestroy(&colp));
1569:   *B = Aperm;
1570:   PetscFunctionReturn(PETSC_SUCCESS);
1571: }

1573: static PetscErrorCode MatGetGhosts_MPIAIJ(Mat mat, PetscInt *nghosts, const PetscInt *ghosts[])
1574: {
1575:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1577:   PetscFunctionBegin;
1578:   PetscCall(MatGetSize(aij->B, NULL, nghosts));
1579:   if (ghosts) *ghosts = aij->garray;
1580:   PetscFunctionReturn(PETSC_SUCCESS);
1581: }

1583: static PetscErrorCode MatGetInfo_MPIAIJ(Mat matin, MatInfoType flag, MatInfo *info)
1584: {
1585:   Mat_MPIAIJ    *mat = (Mat_MPIAIJ *)matin->data;
1586:   Mat            A = mat->A, B = mat->B;
1587:   PetscLogDouble irecv[5];

1589:   PetscFunctionBegin;
1590:   info->block_size = 1.0;
1591:   PetscCall(MatGetInfo(A, MAT_LOCAL, info));

1593:   irecv[0] = info->nz_used;
1594:   irecv[1] = info->nz_allocated;
1595:   irecv[2] = info->nz_unneeded;
1596:   irecv[3] = info->memory;
1597:   irecv[4] = info->mallocs;

1599:   PetscCall(MatGetInfo(B, MAT_LOCAL, info));

1601:   irecv[0] += info->nz_used;
1602:   irecv[1] += info->nz_allocated;
1603:   irecv[2] += info->nz_unneeded;
1604:   irecv[3] += info->memory;
1605:   irecv[4] += info->mallocs;
1606:   if (flag == MAT_LOCAL) {
1607:     info->nz_used      = irecv[0];
1608:     info->nz_allocated = irecv[1];
1609:     info->nz_unneeded  = irecv[2];
1610:     info->memory       = irecv[3];
1611:     info->mallocs      = irecv[4];
1612:   } else if (flag == MAT_GLOBAL_MAX) {
1613:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_MAX, PetscObjectComm((PetscObject)matin)));

1615:     info->nz_used      = irecv[0];
1616:     info->nz_allocated = irecv[1];
1617:     info->nz_unneeded  = irecv[2];
1618:     info->memory       = irecv[3];
1619:     info->mallocs      = irecv[4];
1620:   } else if (flag == MAT_GLOBAL_SUM) {
1621:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_SUM, PetscObjectComm((PetscObject)matin)));

1623:     info->nz_used      = irecv[0];
1624:     info->nz_allocated = irecv[1];
1625:     info->nz_unneeded  = irecv[2];
1626:     info->memory       = irecv[3];
1627:     info->mallocs      = irecv[4];
1628:   }
1629:   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1630:   info->fill_ratio_needed = 0;
1631:   info->factor_mallocs    = 0;
1632:   PetscFunctionReturn(PETSC_SUCCESS);
1633: }

1635: PetscErrorCode MatSetOption_MPIAIJ(Mat A, MatOption op, PetscBool flg)
1636: {
1637:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1639:   PetscFunctionBegin;
1640:   switch (op) {
1641:   case MAT_NEW_NONZERO_LOCATIONS:
1642:   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1643:   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1644:   case MAT_KEEP_NONZERO_PATTERN:
1645:   case MAT_NEW_NONZERO_LOCATION_ERR:
1646:   case MAT_USE_INODES:
1647:   case MAT_IGNORE_ZERO_ENTRIES:
1648:   case MAT_FORM_EXPLICIT_TRANSPOSE:
1649:   case MAT_ROW_ORIENTED:
1650:     MatCheckPreallocated(A, 1);
1651:     if (op == MAT_ROW_ORIENTED) a->roworiented = flg;
1652:     PetscCall(MatSetOption(a->A, op, flg));
1653:     PetscCall(MatSetOption(a->B, op, flg));
1654:     break;
1655:   case MAT_IGNORE_OFF_PROC_ENTRIES:
1656:     a->donotstash = flg;
1657:     break;
1658:   /* Symmetry flags are handled directly by MatSetOption() and they don't affect preallocation */
1659:   case MAT_SPD:
1660:   case MAT_SYMMETRIC:
1661:   case MAT_STRUCTURALLY_SYMMETRIC:
1662:   case MAT_HERMITIAN:
1663:   case MAT_SYMMETRY_ETERNAL:
1664:   case MAT_STRUCTURAL_SYMMETRY_ETERNAL:
1665:   case MAT_SPD_ETERNAL:
1666:     /* if the diagonal matrix is square it inherits some of the properties above */
1667:     if (a->A && A->rmap->n == A->cmap->n) PetscCall(MatSetOption(a->A, op, flg));
1668:     break;
1669:   case MAT_SUBMAT_SINGLEIS:
1670:     A->submat_singleis = flg;
1671:     break;
1672:   default:
1673:     break;
1674:   }
1675:   PetscFunctionReturn(PETSC_SUCCESS);
1676: }

1678: PetscErrorCode MatGetRow_MPIAIJ(Mat matin, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1679: {
1680:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)matin->data;
1681:   PetscScalar *vworkA, *vworkB, **pvA, **pvB, *v_p;
1682:   PetscInt     i, *cworkA, *cworkB, **pcA, **pcB, cstart = matin->cmap->rstart;
1683:   PetscInt     nztot, nzA, nzB, lrow, rstart = matin->rmap->rstart, rend = matin->rmap->rend;
1684:   PetscInt    *cmap, *idx_p;

1686:   PetscFunctionBegin;
1687:   PetscCheck(!mat->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Already active");
1688:   mat->getrowactive = PETSC_TRUE;

1690:   if (!mat->rowvalues && (idx || v)) {
1691:     /*
1692:         allocate enough space to hold information from the longest row.
1693:     */
1694:     Mat_SeqAIJ *Aa = (Mat_SeqAIJ *)mat->A->data, *Ba = (Mat_SeqAIJ *)mat->B->data;
1695:     PetscInt    max = 1, tmp;
1696:     for (i = 0; i < matin->rmap->n; i++) {
1697:       tmp = Aa->i[i + 1] - Aa->i[i] + Ba->i[i + 1] - Ba->i[i];
1698:       if (max < tmp) max = tmp;
1699:     }
1700:     PetscCall(PetscMalloc2(max, &mat->rowvalues, max, &mat->rowindices));
1701:   }

1703:   PetscCheck(row >= rstart && row < rend, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Only local rows");
1704:   lrow = row - rstart;

1706:   pvA = &vworkA;
1707:   pcA = &cworkA;
1708:   pvB = &vworkB;
1709:   pcB = &cworkB;
1710:   if (!v) {
1711:     pvA = NULL;
1712:     pvB = NULL;
1713:   }
1714:   if (!idx) {
1715:     pcA = NULL;
1716:     if (!v) pcB = NULL;
1717:   }
1718:   PetscUseTypeMethod(mat->A, getrow, lrow, &nzA, pcA, pvA);
1719:   PetscUseTypeMethod(mat->B, getrow, lrow, &nzB, pcB, pvB);
1720:   nztot = nzA + nzB;

1722:   cmap = mat->garray;
1723:   if (v || idx) {
1724:     if (nztot) {
1725:       /* Sort by increasing column numbers, assuming A and B already sorted */
1726:       PetscInt imark = -1;
1727:       if (v) {
1728:         *v = v_p = mat->rowvalues;
1729:         for (i = 0; i < nzB; i++) {
1730:           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1731:           else break;
1732:         }
1733:         imark = i;
1734:         for (i = 0; i < nzA; i++) v_p[imark + i] = vworkA[i];
1735:         for (i = imark; i < nzB; i++) v_p[nzA + i] = vworkB[i];
1736:       }
1737:       if (idx) {
1738:         *idx = idx_p = mat->rowindices;
1739:         if (imark > -1) {
1740:           for (i = 0; i < imark; i++) idx_p[i] = cmap[cworkB[i]];
1741:         } else {
1742:           for (i = 0; i < nzB; i++) {
1743:             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1744:             else break;
1745:           }
1746:           imark = i;
1747:         }
1748:         for (i = 0; i < nzA; i++) idx_p[imark + i] = cstart + cworkA[i];
1749:         for (i = imark; i < nzB; i++) idx_p[nzA + i] = cmap[cworkB[i]];
1750:       }
1751:     } else {
1752:       if (idx) *idx = NULL;
1753:       if (v) *v = NULL;
1754:     }
1755:   }
1756:   *nz = nztot;
1757:   PetscUseTypeMethod(mat->A, restorerow, lrow, &nzA, pcA, pvA);
1758:   PetscUseTypeMethod(mat->B, restorerow, lrow, &nzB, pcB, pvB);
1759:   PetscFunctionReturn(PETSC_SUCCESS);
1760: }

1762: PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1763: {
1764:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1766:   PetscFunctionBegin;
1767:   PetscCheck(aij->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "MatGetRow() must be called first");
1768:   aij->getrowactive = PETSC_FALSE;
1769:   PetscFunctionReturn(PETSC_SUCCESS);
1770: }

1772: static PetscErrorCode MatNorm_MPIAIJ(Mat mat, NormType type, PetscReal *norm)
1773: {
1774:   Mat_MPIAIJ      *aij  = (Mat_MPIAIJ *)mat->data;
1775:   Mat_SeqAIJ      *amat = (Mat_SeqAIJ *)aij->A->data, *bmat = (Mat_SeqAIJ *)aij->B->data;
1776:   PetscInt         i, j;
1777:   PetscReal        sum = 0.0;
1778:   const MatScalar *v, *amata, *bmata;

1780:   PetscFunctionBegin;
1781:   if (aij->size == 1) {
1782:     PetscCall(MatNorm(aij->A, type, norm));
1783:   } else {
1784:     PetscCall(MatSeqAIJGetArrayRead(aij->A, &amata));
1785:     PetscCall(MatSeqAIJGetArrayRead(aij->B, &bmata));
1786:     if (type == NORM_FROBENIUS) {
1787:       v = amata;
1788:       for (i = 0; i < amat->nz; i++) {
1789:         sum += PetscRealPart(PetscConj(*v) * (*v));
1790:         v++;
1791:       }
1792:       v = bmata;
1793:       for (i = 0; i < bmat->nz; i++) {
1794:         sum += PetscRealPart(PetscConj(*v) * (*v));
1795:         v++;
1796:       }
1797:       PetscCallMPI(MPIU_Allreduce(&sum, norm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1798:       *norm = PetscSqrtReal(*norm);
1799:       PetscCall(PetscLogFlops(2.0 * amat->nz + 2.0 * bmat->nz));
1800:     } else if (type == NORM_1) { /* max column norm */
1801:       Vec          col, bcol;
1802:       PetscScalar *array;
1803:       PetscInt    *jj, *garray = aij->garray;

1805:       PetscCall(MatCreateVecs(mat, &col, NULL));
1806:       PetscCall(VecGetArrayWrite(col, &array));
1807:       v  = amata;
1808:       jj = amat->j;
1809:       for (j = 0; j < amat->nz; j++) array[*jj++] += PetscAbsScalar(*v++);
1810:       PetscCall(VecRestoreArrayWrite(col, &array));
1811:       PetscCall(MatCreateVecs(aij->B, &bcol, NULL));
1812:       PetscCall(VecGetArrayWrite(bcol, &array));
1813:       v  = bmata;
1814:       jj = bmat->j;
1815:       for (j = 0; j < bmat->nz; j++) array[*jj++] += PetscAbsScalar(*v++);
1816:       PetscCall(VecSetValues(col, aij->B->cmap->n, garray, array, ADD_VALUES));
1817:       PetscCall(VecRestoreArrayWrite(bcol, &array));
1818:       PetscCall(VecDestroy(&bcol));
1819:       PetscCall(VecAssemblyBegin(col));
1820:       PetscCall(VecAssemblyEnd(col));
1821:       PetscCall(VecNorm(col, NORM_INFINITY, norm));
1822:       PetscCall(VecDestroy(&col));
1823:     } else if (type == NORM_INFINITY) { /* max row norm */
1824:       *norm = 0.0;
1825:       for (j = 0; j < aij->A->rmap->n; j++) {
1826:         v   = PetscSafePointerPlusOffset(amata, amat->i[j]);
1827:         sum = 0.0;
1828:         for (i = 0; i < amat->i[j + 1] - amat->i[j]; i++) {
1829:           sum += PetscAbsScalar(*v);
1830:           v++;
1831:         }
1832:         v = PetscSafePointerPlusOffset(bmata, bmat->i[j]);
1833:         for (i = 0; i < bmat->i[j + 1] - bmat->i[j]; i++) {
1834:           sum += PetscAbsScalar(*v);
1835:           v++;
1836:         }
1837:         if (sum > *norm) *norm = sum;
1838:       }
1839:       PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, norm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)mat)));
1840:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1841:     } else SETERRQ(PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "No support for two norm");
1842:     PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &amata));
1843:     PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &bmata));
1844:   }
1845:   PetscFunctionReturn(PETSC_SUCCESS);
1846: }

1848: static PetscErrorCode MatTranspose_MPIAIJ(Mat A, MatReuse reuse, Mat *matout)
1849: {
1850:   Mat_MPIAIJ      *a    = (Mat_MPIAIJ *)A->data, *b;
1851:   Mat_SeqAIJ      *Aloc = (Mat_SeqAIJ *)a->A->data, *Bloc = (Mat_SeqAIJ *)a->B->data, *sub_B_diag;
1852:   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;
1853:   const PetscInt  *ai, *aj, *bi, *bj, *B_diag_i;
1854:   Mat              B, A_diag, *B_diag;
1855:   const MatScalar *pbv, *bv;

1857:   PetscFunctionBegin;
1858:   if (reuse == MAT_REUSE_MATRIX) PetscCall(MatTransposeCheckNonzeroState_Private(A, *matout));
1859:   ma = A->rmap->n;
1860:   na = A->cmap->n;
1861:   mb = a->B->rmap->n;
1862:   nb = a->B->cmap->n;
1863:   ai = Aloc->i;
1864:   aj = Aloc->j;
1865:   bi = Bloc->i;
1866:   bj = Bloc->j;
1867:   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1868:     PetscInt            *d_nnz, *g_nnz, *o_nnz;
1869:     PetscSFNode         *oloc;
1870:     PETSC_UNUSED PetscSF sf;

1872:     PetscCall(PetscMalloc4(na, &d_nnz, na, &o_nnz, nb, &g_nnz, nb, &oloc));
1873:     /* compute d_nnz for preallocation */
1874:     PetscCall(PetscArrayzero(d_nnz, na));
1875:     for (i = 0; i < ai[ma]; i++) d_nnz[aj[i]]++;
1876:     /* compute local off-diagonal contributions */
1877:     PetscCall(PetscArrayzero(g_nnz, nb));
1878:     for (i = 0; i < bi[ma]; i++) g_nnz[bj[i]]++;
1879:     /* map those to global */
1880:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1881:     PetscCall(PetscSFSetGraphLayout(sf, A->cmap, nb, NULL, PETSC_USE_POINTER, a->garray));
1882:     PetscCall(PetscSFSetFromOptions(sf));
1883:     PetscCall(PetscArrayzero(o_nnz, na));
1884:     PetscCall(PetscSFReduceBegin(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1885:     PetscCall(PetscSFReduceEnd(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1886:     PetscCall(PetscSFDestroy(&sf));

1888:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
1889:     PetscCall(MatSetSizes(B, A->cmap->n, A->rmap->n, N, M));
1890:     PetscCall(MatSetBlockSizes(B, A->cmap->bs, A->rmap->bs));
1891:     PetscCall(MatSetType(B, ((PetscObject)A)->type_name));
1892:     PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
1893:     PetscCall(PetscFree4(d_nnz, o_nnz, g_nnz, oloc));
1894:   } else {
1895:     B = *matout;
1896:     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE));
1897:   }

1899:   b           = (Mat_MPIAIJ *)B->data;
1900:   A_diag      = a->A;
1901:   B_diag      = &b->A;
1902:   sub_B_diag  = (Mat_SeqAIJ *)(*B_diag)->data;
1903:   A_diag_ncol = A_diag->cmap->N;
1904:   B_diag_ilen = sub_B_diag->ilen;
1905:   B_diag_i    = sub_B_diag->i;

1907:   /* Set ilen for diagonal of B */
1908:   for (i = 0; i < A_diag_ncol; i++) B_diag_ilen[i] = B_diag_i[i + 1] - B_diag_i[i];

1910:   /* Transpose the diagonal part of the matrix. In contrast to the off-diagonal part, this can be done
1911:   very quickly (=without using MatSetValues), because all writes are local. */
1912:   PetscCall(MatTransposeSetPrecursor(A_diag, *B_diag));
1913:   PetscCall(MatTranspose(A_diag, MAT_REUSE_MATRIX, B_diag));

1915:   /* copy over the B part */
1916:   PetscCall(PetscMalloc1(bi[mb], &cols));
1917:   PetscCall(MatSeqAIJGetArrayRead(a->B, &bv));
1918:   pbv = bv;
1919:   row = A->rmap->rstart;
1920:   for (i = 0; i < bi[mb]; i++) cols[i] = a->garray[bj[i]];
1921:   cols_tmp = cols;
1922:   for (i = 0; i < mb; i++) {
1923:     ncol = bi[i + 1] - bi[i];
1924:     PetscCall(MatSetValues(B, ncol, cols_tmp, 1, &row, pbv, INSERT_VALUES));
1925:     row++;
1926:     if (pbv) pbv += ncol;
1927:     if (cols_tmp) cols_tmp += ncol;
1928:   }
1929:   PetscCall(PetscFree(cols));
1930:   PetscCall(MatSeqAIJRestoreArrayRead(a->B, &bv));

1932:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
1933:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
1934:   if (reuse == MAT_INITIAL_MATRIX || reuse == MAT_REUSE_MATRIX) {
1935:     *matout = B;
1936:   } else {
1937:     PetscCall(MatHeaderMerge(A, &B));
1938:   }
1939:   PetscFunctionReturn(PETSC_SUCCESS);
1940: }

1942: static PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat, Vec ll, Vec rr)
1943: {
1944:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
1945:   Mat         a = aij->A, b = aij->B;
1946:   PetscInt    s1, s2, s3;

1948:   PetscFunctionBegin;
1949:   PetscCall(MatGetLocalSize(mat, &s2, &s3));
1950:   if (rr) {
1951:     PetscCall(VecGetLocalSize(rr, &s1));
1952:     PetscCheck(s1 == s3, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "right vector non-conforming local size");
1953:     /* Overlap communication with computation. */
1954:     PetscCall(VecScatterBegin(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1955:   }
1956:   if (ll) {
1957:     PetscCall(VecGetLocalSize(ll, &s1));
1958:     PetscCheck(s1 == s2, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "left vector non-conforming local size");
1959:     PetscUseTypeMethod(b, diagonalscale, ll, NULL);
1960:   }
1961:   /* scale  the diagonal block */
1962:   PetscUseTypeMethod(a, diagonalscale, ll, rr);

1964:   if (rr) {
1965:     /* Do a scatter end and then right scale the off-diagonal block */
1966:     PetscCall(VecScatterEnd(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1967:     PetscUseTypeMethod(b, diagonalscale, NULL, aij->lvec);
1968:   }
1969:   PetscFunctionReturn(PETSC_SUCCESS);
1970: }

1972: static PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
1973: {
1974:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1976:   PetscFunctionBegin;
1977:   PetscCall(MatSetUnfactored(a->A));
1978:   PetscFunctionReturn(PETSC_SUCCESS);
1979: }

1981: static PetscErrorCode MatEqual_MPIAIJ(Mat A, Mat B, PetscBool *flag)
1982: {
1983:   Mat_MPIAIJ *matB = (Mat_MPIAIJ *)B->data, *matA = (Mat_MPIAIJ *)A->data;
1984:   Mat         a, b, c, d;

1986:   PetscFunctionBegin;
1987:   a = matA->A;
1988:   b = matA->B;
1989:   c = matB->A;
1990:   d = matB->B;

1992:   PetscCall(MatEqual(a, c, flag));
1993:   if (*flag) PetscCall(MatEqual(b, d, flag));
1994:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, flag, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)A)));
1995:   PetscFunctionReturn(PETSC_SUCCESS);
1996: }

1998: static PetscErrorCode MatCopy_MPIAIJ(Mat A, Mat B, MatStructure str)
1999: {
2000:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2001:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2003:   PetscFunctionBegin;
2004:   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2005:   if (str != SAME_NONZERO_PATTERN || A->ops->copy != B->ops->copy) {
2006:     /* because of the column compression in the off-processor part of the matrix a->B,
2007:        the number of columns in a->B and b->B may be different, hence we cannot call
2008:        the MatCopy() directly on the two parts. If need be, we can provide a more
2009:        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2010:        then copying the submatrices */
2011:     PetscCall(MatCopy_Basic(A, B, str));
2012:   } else {
2013:     PetscCall(MatCopy(a->A, b->A, str));
2014:     PetscCall(MatCopy(a->B, b->B, str));
2015:   }
2016:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2017:   PetscFunctionReturn(PETSC_SUCCESS);
2018: }

2020: /*
2021:    Computes the number of nonzeros per row needed for preallocation when X and Y
2022:    have different nonzero structure.
2023: */
2024: 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)
2025: {
2026:   PetscInt i, j, k, nzx, nzy;

2028:   PetscFunctionBegin;
2029:   /* Set the number of nonzeros in the new matrix */
2030:   for (i = 0; i < m; i++) {
2031:     const PetscInt *xjj = PetscSafePointerPlusOffset(xj, xi[i]), *yjj = PetscSafePointerPlusOffset(yj, yi[i]);
2032:     nzx    = xi[i + 1] - xi[i];
2033:     nzy    = yi[i + 1] - yi[i];
2034:     nnz[i] = 0;
2035:     for (j = 0, k = 0; j < nzx; j++) {                                /* Point in X */
2036:       for (; k < nzy && yltog[yjj[k]] < xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2037:       if (k < nzy && yltog[yjj[k]] == xltog[xjj[j]]) k++;             /* Skip duplicate */
2038:       nnz[i]++;
2039:     }
2040:     for (; k < nzy; k++) nnz[i]++;
2041:   }
2042:   PetscFunctionReturn(PETSC_SUCCESS);
2043: }

2045: /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2046: static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y, const PetscInt *yltog, Mat X, const PetscInt *xltog, PetscInt *nnz)
2047: {
2048:   PetscInt    m = Y->rmap->N;
2049:   Mat_SeqAIJ *x = (Mat_SeqAIJ *)X->data;
2050:   Mat_SeqAIJ *y = (Mat_SeqAIJ *)Y->data;

2052:   PetscFunctionBegin;
2053:   PetscCall(MatAXPYGetPreallocation_MPIX_private(m, x->i, x->j, xltog, y->i, y->j, yltog, nnz));
2054:   PetscFunctionReturn(PETSC_SUCCESS);
2055: }

2057: static PetscErrorCode MatAXPY_MPIAIJ(Mat Y, PetscScalar a, Mat X, MatStructure str)
2058: {
2059:   Mat_MPIAIJ *xx = (Mat_MPIAIJ *)X->data, *yy = (Mat_MPIAIJ *)Y->data;

2061:   PetscFunctionBegin;
2062:   if (str == SAME_NONZERO_PATTERN) {
2063:     PetscCall(MatAXPY(yy->A, a, xx->A, str));
2064:     PetscCall(MatAXPY(yy->B, a, xx->B, str));
2065:   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2066:     PetscCall(MatAXPY_Basic(Y, a, X, str));
2067:   } else {
2068:     Mat       B;
2069:     PetscInt *nnz_d, *nnz_o;

2071:     PetscCall(PetscMalloc1(yy->A->rmap->N, &nnz_d));
2072:     PetscCall(PetscMalloc1(yy->B->rmap->N, &nnz_o));
2073:     PetscCall(MatCreate(PetscObjectComm((PetscObject)Y), &B));
2074:     PetscCall(PetscObjectSetName((PetscObject)B, ((PetscObject)Y)->name));
2075:     PetscCall(MatSetLayouts(B, Y->rmap, Y->cmap));
2076:     PetscCall(MatSetType(B, ((PetscObject)Y)->type_name));
2077:     PetscCall(MatAXPYGetPreallocation_SeqAIJ(yy->A, xx->A, nnz_d));
2078:     PetscCall(MatAXPYGetPreallocation_MPIAIJ(yy->B, yy->garray, xx->B, xx->garray, nnz_o));
2079:     PetscCall(MatMPIAIJSetPreallocation(B, 0, nnz_d, 0, nnz_o));
2080:     PetscCall(MatAXPY_BasicWithPreallocation(B, Y, a, X, str));
2081:     PetscCall(MatHeaderMerge(Y, &B));
2082:     PetscCall(PetscFree(nnz_d));
2083:     PetscCall(PetscFree(nnz_o));
2084:   }
2085:   PetscFunctionReturn(PETSC_SUCCESS);
2086: }

2088: PETSC_INTERN PetscErrorCode MatConjugate_SeqAIJ(Mat);

2090: static PetscErrorCode MatConjugate_MPIAIJ(Mat mat)
2091: {
2092:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2094:   PetscFunctionBegin;
2095:   PetscCall(MatConjugate_SeqAIJ(aij->A));
2096:   PetscCall(MatConjugate_SeqAIJ(aij->B));
2097:   PetscFunctionReturn(PETSC_SUCCESS);
2098: }

2100: static PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2101: {
2102:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2104:   PetscFunctionBegin;
2105:   PetscCall(MatRealPart(a->A));
2106:   PetscCall(MatRealPart(a->B));
2107:   PetscFunctionReturn(PETSC_SUCCESS);
2108: }

2110: static PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2111: {
2112:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2114:   PetscFunctionBegin;
2115:   PetscCall(MatImaginaryPart(a->A));
2116:   PetscCall(MatImaginaryPart(a->B));
2117:   PetscFunctionReturn(PETSC_SUCCESS);
2118: }

2120: static PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2121: {
2122:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
2123:   PetscInt           i, *idxb = NULL, m = A->rmap->n;
2124:   PetscScalar       *vv;
2125:   Vec                vB, vA;
2126:   const PetscScalar *va, *vb;

2128:   PetscFunctionBegin;
2129:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2130:   PetscCall(MatGetRowMaxAbs(a->A, vA, idx));

2132:   PetscCall(VecGetArrayRead(vA, &va));
2133:   if (idx) {
2134:     for (i = 0; i < m; i++) {
2135:       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2136:     }
2137:   }

2139:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2140:   PetscCall(PetscMalloc1(m, &idxb));
2141:   PetscCall(MatGetRowMaxAbs(a->B, vB, idxb));

2143:   PetscCall(VecGetArrayWrite(v, &vv));
2144:   PetscCall(VecGetArrayRead(vB, &vb));
2145:   for (i = 0; i < m; i++) {
2146:     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2147:       vv[i] = vb[i];
2148:       if (idx) idx[i] = a->garray[idxb[i]];
2149:     } else {
2150:       vv[i] = va[i];
2151:       if (idx && PetscAbsScalar(va[i]) == PetscAbsScalar(vb[i]) && idxb[i] != -1 && idx[i] > a->garray[idxb[i]]) idx[i] = a->garray[idxb[i]];
2152:     }
2153:   }
2154:   PetscCall(VecRestoreArrayWrite(v, &vv));
2155:   PetscCall(VecRestoreArrayRead(vA, &va));
2156:   PetscCall(VecRestoreArrayRead(vB, &vb));
2157:   PetscCall(PetscFree(idxb));
2158:   PetscCall(VecDestroy(&vA));
2159:   PetscCall(VecDestroy(&vB));
2160:   PetscFunctionReturn(PETSC_SUCCESS);
2161: }

2163: static PetscErrorCode MatGetRowSumAbs_MPIAIJ(Mat A, Vec v)
2164: {
2165:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2166:   Vec         vB, vA;

2168:   PetscFunctionBegin;
2169:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2170:   PetscCall(MatGetRowSumAbs(a->A, vA));
2171:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2172:   PetscCall(MatGetRowSumAbs(a->B, vB));
2173:   PetscCall(VecAXPY(vA, 1.0, vB));
2174:   PetscCall(VecDestroy(&vB));
2175:   PetscCall(VecCopy(vA, v));
2176:   PetscCall(VecDestroy(&vA));
2177:   PetscFunctionReturn(PETSC_SUCCESS);
2178: }

2180: static PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2181: {
2182:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2183:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2184:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2185:   PetscInt          *cmap = mat->garray;
2186:   PetscInt          *diagIdx, *offdiagIdx;
2187:   Vec                diagV, offdiagV;
2188:   PetscScalar       *a, *diagA, *offdiagA;
2189:   const PetscScalar *ba, *bav;
2190:   PetscInt           r, j, col, ncols, *bi, *bj;
2191:   Mat                B = mat->B;
2192:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2194:   PetscFunctionBegin;
2195:   /* When a process holds entire A and other processes have no entry */
2196:   if (A->cmap->N == n) {
2197:     PetscCall(VecGetArrayWrite(v, &diagA));
2198:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2199:     PetscCall(MatGetRowMinAbs(mat->A, diagV, idx));
2200:     PetscCall(VecDestroy(&diagV));
2201:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2202:     PetscFunctionReturn(PETSC_SUCCESS);
2203:   } else if (n == 0) {
2204:     if (m) {
2205:       PetscCall(VecGetArrayWrite(v, &a));
2206:       for (r = 0; r < m; r++) {
2207:         a[r] = 0.0;
2208:         if (idx) idx[r] = -1;
2209:       }
2210:       PetscCall(VecRestoreArrayWrite(v, &a));
2211:     }
2212:     PetscFunctionReturn(PETSC_SUCCESS);
2213:   }

2215:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2216:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2217:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2218:   PetscCall(MatGetRowMinAbs(mat->A, diagV, diagIdx));

2220:   /* Get offdiagIdx[] for implicit 0.0 */
2221:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2222:   ba = bav;
2223:   bi = b->i;
2224:   bj = b->j;
2225:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2226:   for (r = 0; r < m; r++) {
2227:     ncols = bi[r + 1] - bi[r];
2228:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2229:       offdiagA[r]   = *ba;
2230:       offdiagIdx[r] = cmap[0];
2231:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2232:       offdiagA[r] = 0.0;

2234:       /* Find first hole in the cmap */
2235:       for (j = 0; j < ncols; j++) {
2236:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2237:         if (col > j && j < cstart) {
2238:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2239:           break;
2240:         } else if (col > j + n && j >= cstart) {
2241:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2242:           break;
2243:         }
2244:       }
2245:       if (j == ncols && ncols < A->cmap->N - n) {
2246:         /* a hole is outside compressed Bcols */
2247:         if (ncols == 0) {
2248:           if (cstart) {
2249:             offdiagIdx[r] = 0;
2250:           } else offdiagIdx[r] = cend;
2251:         } else { /* ncols > 0 */
2252:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2253:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2254:         }
2255:       }
2256:     }

2258:     for (j = 0; j < ncols; j++) {
2259:       if (PetscAbsScalar(offdiagA[r]) > PetscAbsScalar(*ba)) {
2260:         offdiagA[r]   = *ba;
2261:         offdiagIdx[r] = cmap[*bj];
2262:       }
2263:       ba++;
2264:       bj++;
2265:     }
2266:   }

2268:   PetscCall(VecGetArrayWrite(v, &a));
2269:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2270:   for (r = 0; r < m; ++r) {
2271:     if (PetscAbsScalar(diagA[r]) < PetscAbsScalar(offdiagA[r])) {
2272:       a[r] = diagA[r];
2273:       if (idx) idx[r] = cstart + diagIdx[r];
2274:     } else if (PetscAbsScalar(diagA[r]) == PetscAbsScalar(offdiagA[r])) {
2275:       a[r] = diagA[r];
2276:       if (idx) {
2277:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2278:           idx[r] = cstart + diagIdx[r];
2279:         } else idx[r] = offdiagIdx[r];
2280:       }
2281:     } else {
2282:       a[r] = offdiagA[r];
2283:       if (idx) idx[r] = offdiagIdx[r];
2284:     }
2285:   }
2286:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2287:   PetscCall(VecRestoreArrayWrite(v, &a));
2288:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2289:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2290:   PetscCall(VecDestroy(&diagV));
2291:   PetscCall(VecDestroy(&offdiagV));
2292:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2293:   PetscFunctionReturn(PETSC_SUCCESS);
2294: }

2296: static PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2297: {
2298:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2299:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2300:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2301:   PetscInt          *cmap = mat->garray;
2302:   PetscInt          *diagIdx, *offdiagIdx;
2303:   Vec                diagV, offdiagV;
2304:   PetscScalar       *a, *diagA, *offdiagA;
2305:   const PetscScalar *ba, *bav;
2306:   PetscInt           r, j, col, ncols, *bi, *bj;
2307:   Mat                B = mat->B;
2308:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2310:   PetscFunctionBegin;
2311:   /* When a process holds entire A and other processes have no entry */
2312:   if (A->cmap->N == n) {
2313:     PetscCall(VecGetArrayWrite(v, &diagA));
2314:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2315:     PetscCall(MatGetRowMin(mat->A, diagV, idx));
2316:     PetscCall(VecDestroy(&diagV));
2317:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2318:     PetscFunctionReturn(PETSC_SUCCESS);
2319:   } else if (n == 0) {
2320:     if (m) {
2321:       PetscCall(VecGetArrayWrite(v, &a));
2322:       for (r = 0; r < m; r++) {
2323:         a[r] = PETSC_MAX_REAL;
2324:         if (idx) idx[r] = -1;
2325:       }
2326:       PetscCall(VecRestoreArrayWrite(v, &a));
2327:     }
2328:     PetscFunctionReturn(PETSC_SUCCESS);
2329:   }

2331:   PetscCall(PetscCalloc2(m, &diagIdx, m, &offdiagIdx));
2332:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2333:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2334:   PetscCall(MatGetRowMin(mat->A, diagV, diagIdx));

2336:   /* Get offdiagIdx[] for implicit 0.0 */
2337:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2338:   ba = bav;
2339:   bi = b->i;
2340:   bj = b->j;
2341:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2342:   for (r = 0; r < m; r++) {
2343:     ncols = bi[r + 1] - bi[r];
2344:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2345:       offdiagA[r]   = *ba;
2346:       offdiagIdx[r] = cmap[0];
2347:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2348:       offdiagA[r] = 0.0;

2350:       /* Find first hole in the cmap */
2351:       for (j = 0; j < ncols; j++) {
2352:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2353:         if (col > j && j < cstart) {
2354:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2355:           break;
2356:         } else if (col > j + n && j >= cstart) {
2357:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2358:           break;
2359:         }
2360:       }
2361:       if (j == ncols && ncols < A->cmap->N - n) {
2362:         /* a hole is outside compressed Bcols */
2363:         if (ncols == 0) {
2364:           if (cstart) {
2365:             offdiagIdx[r] = 0;
2366:           } else offdiagIdx[r] = cend;
2367:         } else { /* ncols > 0 */
2368:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2369:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2370:         }
2371:       }
2372:     }

2374:     for (j = 0; j < ncols; j++) {
2375:       if (PetscRealPart(offdiagA[r]) > PetscRealPart(*ba)) {
2376:         offdiagA[r]   = *ba;
2377:         offdiagIdx[r] = cmap[*bj];
2378:       }
2379:       ba++;
2380:       bj++;
2381:     }
2382:   }

2384:   PetscCall(VecGetArrayWrite(v, &a));
2385:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2386:   for (r = 0; r < m; ++r) {
2387:     if (PetscRealPart(diagA[r]) < PetscRealPart(offdiagA[r])) {
2388:       a[r] = diagA[r];
2389:       if (idx) idx[r] = cstart + diagIdx[r];
2390:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2391:       a[r] = diagA[r];
2392:       if (idx) {
2393:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2394:           idx[r] = cstart + diagIdx[r];
2395:         } else idx[r] = offdiagIdx[r];
2396:       }
2397:     } else {
2398:       a[r] = offdiagA[r];
2399:       if (idx) idx[r] = offdiagIdx[r];
2400:     }
2401:   }
2402:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2403:   PetscCall(VecRestoreArrayWrite(v, &a));
2404:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2405:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2406:   PetscCall(VecDestroy(&diagV));
2407:   PetscCall(VecDestroy(&offdiagV));
2408:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2409:   PetscFunctionReturn(PETSC_SUCCESS);
2410: }

2412: static PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2413: {
2414:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2415:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2416:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2417:   PetscInt          *cmap = mat->garray;
2418:   PetscInt          *diagIdx, *offdiagIdx;
2419:   Vec                diagV, offdiagV;
2420:   PetscScalar       *a, *diagA, *offdiagA;
2421:   const PetscScalar *ba, *bav;
2422:   PetscInt           r, j, col, ncols, *bi, *bj;
2423:   Mat                B = mat->B;
2424:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2426:   PetscFunctionBegin;
2427:   /* When a process holds entire A and other processes have no entry */
2428:   if (A->cmap->N == n) {
2429:     PetscCall(VecGetArrayWrite(v, &diagA));
2430:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2431:     PetscCall(MatGetRowMax(mat->A, diagV, idx));
2432:     PetscCall(VecDestroy(&diagV));
2433:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2434:     PetscFunctionReturn(PETSC_SUCCESS);
2435:   } else if (n == 0) {
2436:     if (m) {
2437:       PetscCall(VecGetArrayWrite(v, &a));
2438:       for (r = 0; r < m; r++) {
2439:         a[r] = PETSC_MIN_REAL;
2440:         if (idx) idx[r] = -1;
2441:       }
2442:       PetscCall(VecRestoreArrayWrite(v, &a));
2443:     }
2444:     PetscFunctionReturn(PETSC_SUCCESS);
2445:   }

2447:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2448:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2449:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2450:   PetscCall(MatGetRowMax(mat->A, diagV, diagIdx));

2452:   /* Get offdiagIdx[] for implicit 0.0 */
2453:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2454:   ba = bav;
2455:   bi = b->i;
2456:   bj = b->j;
2457:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2458:   for (r = 0; r < m; r++) {
2459:     ncols = bi[r + 1] - bi[r];
2460:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2461:       offdiagA[r]   = *ba;
2462:       offdiagIdx[r] = cmap[0];
2463:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2464:       offdiagA[r] = 0.0;

2466:       /* Find first hole in the cmap */
2467:       for (j = 0; j < ncols; j++) {
2468:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2469:         if (col > j && j < cstart) {
2470:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2471:           break;
2472:         } else if (col > j + n && j >= cstart) {
2473:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2474:           break;
2475:         }
2476:       }
2477:       if (j == ncols && ncols < A->cmap->N - n) {
2478:         /* a hole is outside compressed Bcols */
2479:         if (ncols == 0) {
2480:           if (cstart) {
2481:             offdiagIdx[r] = 0;
2482:           } else offdiagIdx[r] = cend;
2483:         } else { /* ncols > 0 */
2484:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2485:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2486:         }
2487:       }
2488:     }

2490:     for (j = 0; j < ncols; j++) {
2491:       if (PetscRealPart(offdiagA[r]) < PetscRealPart(*ba)) {
2492:         offdiagA[r]   = *ba;
2493:         offdiagIdx[r] = cmap[*bj];
2494:       }
2495:       ba++;
2496:       bj++;
2497:     }
2498:   }

2500:   PetscCall(VecGetArrayWrite(v, &a));
2501:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2502:   for (r = 0; r < m; ++r) {
2503:     if (PetscRealPart(diagA[r]) > PetscRealPart(offdiagA[r])) {
2504:       a[r] = diagA[r];
2505:       if (idx) idx[r] = cstart + diagIdx[r];
2506:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2507:       a[r] = diagA[r];
2508:       if (idx) {
2509:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2510:           idx[r] = cstart + diagIdx[r];
2511:         } else idx[r] = offdiagIdx[r];
2512:       }
2513:     } else {
2514:       a[r] = offdiagA[r];
2515:       if (idx) idx[r] = offdiagIdx[r];
2516:     }
2517:   }
2518:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2519:   PetscCall(VecRestoreArrayWrite(v, &a));
2520:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2521:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2522:   PetscCall(VecDestroy(&diagV));
2523:   PetscCall(VecDestroy(&offdiagV));
2524:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2525:   PetscFunctionReturn(PETSC_SUCCESS);
2526: }

2528: PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat, Mat *newmat)
2529: {
2530:   Mat *dummy;

2532:   PetscFunctionBegin;
2533:   PetscCall(MatCreateSubMatrix_MPIAIJ_All(mat, MAT_DO_NOT_GET_VALUES, MAT_INITIAL_MATRIX, &dummy));
2534:   *newmat = *dummy;
2535:   PetscCall(PetscFree(dummy));
2536:   PetscFunctionReturn(PETSC_SUCCESS);
2537: }

2539: static PetscErrorCode MatInvertBlockDiagonal_MPIAIJ(Mat A, const PetscScalar **values)
2540: {
2541:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2543:   PetscFunctionBegin;
2544:   PetscCall(MatInvertBlockDiagonal(a->A, values));
2545:   A->factorerrortype = a->A->factorerrortype;
2546:   PetscFunctionReturn(PETSC_SUCCESS);
2547: }

2549: static PetscErrorCode MatSetRandom_MPIAIJ(Mat x, PetscRandom rctx)
2550: {
2551:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)x->data;

2553:   PetscFunctionBegin;
2554:   PetscCheck(x->assembled || x->preallocated, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONGSTATE, "MatSetRandom on an unassembled and unpreallocated MATMPIAIJ is not allowed");
2555:   PetscCall(MatSetRandom(aij->A, rctx));
2556:   if (x->assembled) {
2557:     PetscCall(MatSetRandom(aij->B, rctx));
2558:   } else {
2559:     PetscCall(MatSetRandomSkipColumnRange_SeqAIJ_Private(aij->B, x->cmap->rstart, x->cmap->rend, rctx));
2560:   }
2561:   PetscCall(MatAssemblyBegin(x, MAT_FINAL_ASSEMBLY));
2562:   PetscCall(MatAssemblyEnd(x, MAT_FINAL_ASSEMBLY));
2563:   PetscFunctionReturn(PETSC_SUCCESS);
2564: }

2566: static PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A, PetscBool sc)
2567: {
2568:   PetscFunctionBegin;
2569:   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2570:   else A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ;
2571:   PetscFunctionReturn(PETSC_SUCCESS);
2572: }

2574: /*@
2575:   MatMPIAIJGetNumberNonzeros - gets the number of nonzeros in the matrix on this MPI rank

2577:   Not Collective

2579:   Input Parameter:
2580: . A - the matrix

2582:   Output Parameter:
2583: . nz - the number of nonzeros

2585:   Level: advanced

2587: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2588: @*/
2589: PetscErrorCode MatMPIAIJGetNumberNonzeros(Mat A, PetscCount *nz)
2590: {
2591:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)A->data;
2592:   Mat_SeqAIJ *aaij = (Mat_SeqAIJ *)maij->A->data, *baij = (Mat_SeqAIJ *)maij->B->data;
2593:   PetscBool   isaij;

2595:   PetscFunctionBegin;
2596:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)A, MATMPIAIJ, &isaij));
2597:   PetscCheck(isaij, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Not for type %s", ((PetscObject)A)->type_name);
2598:   *nz = aaij->i[A->rmap->n] + baij->i[A->rmap->n];
2599:   PetscFunctionReturn(PETSC_SUCCESS);
2600: }

2602: /*@
2603:   MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap

2605:   Collective

2607:   Input Parameters:
2608: + A  - the matrix
2609: - sc - `PETSC_TRUE` indicates use the scalable algorithm (default is not to use the scalable algorithm)

2611:   Level: advanced

2613: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2614: @*/
2615: PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A, PetscBool sc)
2616: {
2617:   PetscFunctionBegin;
2618:   PetscTryMethod(A, "MatMPIAIJSetUseScalableIncreaseOverlap_C", (Mat, PetscBool), (A, sc));
2619:   PetscFunctionReturn(PETSC_SUCCESS);
2620: }

2622: PetscErrorCode MatSetFromOptions_MPIAIJ(Mat A, PetscOptionItems PetscOptionsObject)
2623: {
2624:   PetscBool sc = PETSC_FALSE, flg;

2626:   PetscFunctionBegin;
2627:   PetscOptionsHeadBegin(PetscOptionsObject, "MPIAIJ options");
2628:   if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2629:   PetscCall(PetscOptionsBool("-mat_increase_overlap_scalable", "Use a scalable algorithm to compute the overlap", "MatIncreaseOverlap", sc, &sc, &flg));
2630:   if (flg) PetscCall(MatMPIAIJSetUseScalableIncreaseOverlap(A, sc));
2631:   PetscOptionsHeadEnd();
2632:   PetscFunctionReturn(PETSC_SUCCESS);
2633: }

2635: static PetscErrorCode MatShift_MPIAIJ(Mat Y, PetscScalar a)
2636: {
2637:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)Y->data;
2638:   Mat_SeqAIJ *aij  = (Mat_SeqAIJ *)maij->A->data;

2640:   PetscFunctionBegin;
2641:   if (!Y->preallocated) {
2642:     PetscCall(MatMPIAIJSetPreallocation(Y, 1, NULL, 0, NULL));
2643:   } else if (!aij->nz) { /* It does not matter if diagonals of Y only partially lie in maij->A. We just need an estimated preallocation. */
2644:     PetscInt nonew = aij->nonew;
2645:     PetscCall(MatSeqAIJSetPreallocation(maij->A, 1, NULL));
2646:     aij->nonew = nonew;
2647:   }
2648:   PetscCall(MatShift_Basic(Y, a));
2649:   PetscFunctionReturn(PETSC_SUCCESS);
2650: }

2652: static PetscErrorCode MatInvertVariableBlockDiagonal_MPIAIJ(Mat A, PetscInt nblocks, const PetscInt *bsizes, PetscScalar *diag)
2653: {
2654:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2656:   PetscFunctionBegin;
2657:   PetscCall(MatInvertVariableBlockDiagonal(a->A, nblocks, bsizes, diag));
2658:   PetscFunctionReturn(PETSC_SUCCESS);
2659: }

2661: static PetscErrorCode MatEliminateZeros_MPIAIJ(Mat A, PetscBool keep)
2662: {
2663:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2665:   PetscFunctionBegin;
2666:   PetscCall(MatEliminateZeros_SeqAIJ(a->A, keep));        // possibly keep zero diagonal coefficients
2667:   PetscCall(MatEliminateZeros_SeqAIJ(a->B, PETSC_FALSE)); // never keep zero diagonal coefficients
2668:   PetscFunctionReturn(PETSC_SUCCESS);
2669: }

2671: static PetscErrorCode MatGetOrdering_MPIAIJ(Mat A, MatOrderingType type, IS *rperm, IS *cperm)
2672: {
2673:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
2674:   IS              lrowperm, lcolperm;
2675:   PetscInt        i, rstart, rend, *idx;
2676:   const PetscInt *lidx;

2678:   PetscFunctionBegin;
2679:   PetscCall(MatGetOrdering(a->A, type, &lrowperm, &lcolperm));
2680:   PetscCall(MatGetOwnershipRange(A, &rstart, &rend));
2681:   /* Remap row index set to global space */
2682:   PetscCall(ISGetIndices(lrowperm, &lidx));
2683:   PetscCall(PetscMalloc1(rend - rstart, &idx));
2684:   for (i = 0; i + rstart < rend; i++) idx[i] = rstart + lidx[i];
2685:   PetscCall(ISRestoreIndices(lrowperm, &lidx));
2686:   PetscCall(ISDestroy(&lrowperm));
2687:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), rend - rstart, idx, PETSC_OWN_POINTER, rperm));
2688:   PetscCall(ISSetPermutation(*rperm));
2689:   /* Remap column index set to global space */
2690:   PetscCall(ISGetIndices(lcolperm, &lidx));
2691:   PetscCall(PetscMalloc1(rend - rstart, &idx));
2692:   for (i = 0; i + rstart < rend; i++) idx[i] = rstart + lidx[i];
2693:   PetscCall(ISRestoreIndices(lcolperm, &lidx));
2694:   PetscCall(ISDestroy(&lcolperm));
2695:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), rend - rstart, idx, PETSC_OWN_POINTER, cperm));
2696:   PetscCall(ISSetPermutation(*cperm));
2697:   PetscFunctionReturn(PETSC_SUCCESS);
2698: }

2700: static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2701:                                        MatGetRow_MPIAIJ,
2702:                                        MatRestoreRow_MPIAIJ,
2703:                                        MatMult_MPIAIJ,
2704:                                        /* 4*/ MatMultAdd_MPIAIJ,
2705:                                        MatMultTranspose_MPIAIJ,
2706:                                        MatMultTransposeAdd_MPIAIJ,
2707:                                        NULL,
2708:                                        NULL,
2709:                                        NULL,
2710:                                        /*10*/ NULL,
2711:                                        NULL,
2712:                                        NULL,
2713:                                        MatSOR_MPIAIJ,
2714:                                        MatTranspose_MPIAIJ,
2715:                                        /*15*/ MatGetInfo_MPIAIJ,
2716:                                        MatEqual_MPIAIJ,
2717:                                        MatGetDiagonal_MPIAIJ,
2718:                                        MatDiagonalScale_MPIAIJ,
2719:                                        MatNorm_MPIAIJ,
2720:                                        /*20*/ MatAssemblyBegin_MPIAIJ,
2721:                                        MatAssemblyEnd_MPIAIJ,
2722:                                        MatSetOption_MPIAIJ,
2723:                                        MatZeroEntries_MPIAIJ,
2724:                                        /*24*/ MatZeroRows_MPIAIJ,
2725:                                        NULL,
2726:                                        NULL,
2727:                                        NULL,
2728:                                        NULL,
2729:                                        /*29*/ MatSetUp_MPI_Hash,
2730:                                        NULL,
2731:                                        NULL,
2732:                                        MatGetDiagonalBlock_MPIAIJ,
2733:                                        NULL,
2734:                                        /*34*/ MatDuplicate_MPIAIJ,
2735:                                        NULL,
2736:                                        NULL,
2737:                                        NULL,
2738:                                        NULL,
2739:                                        /*39*/ MatAXPY_MPIAIJ,
2740:                                        MatCreateSubMatrices_MPIAIJ,
2741:                                        MatIncreaseOverlap_MPIAIJ,
2742:                                        MatGetValues_MPIAIJ,
2743:                                        MatCopy_MPIAIJ,
2744:                                        /*44*/ MatGetRowMax_MPIAIJ,
2745:                                        MatScale_MPIAIJ,
2746:                                        MatShift_MPIAIJ,
2747:                                        MatDiagonalSet_MPIAIJ,
2748:                                        MatZeroRowsColumns_MPIAIJ,
2749:                                        /*49*/ MatSetRandom_MPIAIJ,
2750:                                        MatGetRowIJ_MPIAIJ,
2751:                                        MatRestoreRowIJ_MPIAIJ,
2752:                                        NULL,
2753:                                        NULL,
2754:                                        /*54*/ MatFDColoringCreate_MPIXAIJ,
2755:                                        NULL,
2756:                                        MatSetUnfactored_MPIAIJ,
2757:                                        MatPermute_MPIAIJ,
2758:                                        NULL,
2759:                                        /*59*/ MatCreateSubMatrix_MPIAIJ,
2760:                                        MatDestroy_MPIAIJ,
2761:                                        MatView_MPIAIJ,
2762:                                        NULL,
2763:                                        NULL,
2764:                                        /*64*/ MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2765:                                        NULL,
2766:                                        NULL,
2767:                                        NULL,
2768:                                        MatGetRowMaxAbs_MPIAIJ,
2769:                                        /*69*/ MatGetRowMinAbs_MPIAIJ,
2770:                                        NULL,
2771:                                        NULL,
2772:                                        MatFDColoringApply_AIJ,
2773:                                        MatSetFromOptions_MPIAIJ,
2774:                                        MatFindZeroDiagonals_MPIAIJ,
2775:                                        /*75*/ NULL,
2776:                                        NULL,
2777:                                        NULL,
2778:                                        MatLoad_MPIAIJ,
2779:                                        NULL,
2780:                                        /*80*/ NULL,
2781:                                        NULL,
2782:                                        NULL,
2783:                                        /*83*/ NULL,
2784:                                        NULL,
2785:                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2786:                                        MatPtAPNumeric_MPIAIJ_MPIAIJ,
2787:                                        NULL,
2788:                                        NULL,
2789:                                        /*89*/ MatBindToCPU_MPIAIJ,
2790:                                        MatProductSetFromOptions_MPIAIJ,
2791:                                        NULL,
2792:                                        NULL,
2793:                                        MatConjugate_MPIAIJ,
2794:                                        /*94*/ NULL,
2795:                                        MatSetValuesRow_MPIAIJ,
2796:                                        MatRealPart_MPIAIJ,
2797:                                        MatImaginaryPart_MPIAIJ,
2798:                                        NULL,
2799:                                        /*99*/ NULL,
2800:                                        NULL,
2801:                                        NULL,
2802:                                        MatGetRowMin_MPIAIJ,
2803:                                        NULL,
2804:                                        /*104*/ MatGetSeqNonzeroStructure_MPIAIJ,
2805:                                        NULL,
2806:                                        MatGetGhosts_MPIAIJ,
2807:                                        NULL,
2808:                                        NULL,
2809:                                        /*109*/ MatMultDiagonalBlock_MPIAIJ,
2810:                                        NULL,
2811:                                        NULL,
2812:                                        NULL,
2813:                                        MatGetMultiProcBlock_MPIAIJ,
2814:                                        /*114*/ MatFindNonzeroRows_MPIAIJ,
2815:                                        MatGetColumnReductions_MPIAIJ,
2816:                                        MatInvertBlockDiagonal_MPIAIJ,
2817:                                        MatInvertVariableBlockDiagonal_MPIAIJ,
2818:                                        MatCreateSubMatricesMPI_MPIAIJ,
2819:                                        /*119*/ NULL,
2820:                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2821:                                        NULL,
2822:                                        NULL,
2823:                                        NULL,
2824:                                        /*124*/ NULL,
2825:                                        MatSetBlockSizes_MPIAIJ,
2826:                                        NULL,
2827:                                        MatFDColoringSetUp_MPIXAIJ,
2828:                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2829:                                        /*129*/ MatCreateMPIMatConcatenateSeqMat_MPIAIJ,
2830:                                        NULL,
2831:                                        NULL,
2832:                                        NULL,
2833:                                        MatCreateGraph_Simple_AIJ,
2834:                                        /*134*/ NULL,
2835:                                        MatEliminateZeros_MPIAIJ,
2836:                                        MatGetRowSumAbs_MPIAIJ,
2837:                                        NULL,
2838:                                        NULL,
2839:                                        /*139*/ NULL,
2840:                                        MatCopyHashToXAIJ_MPI_Hash,
2841:                                        MatGetCurrentMemType_MPIAIJ,
2842:                                        NULL,
2843:                                        NULL,
2844:                                        /*144*/ NULL,
2845:                                        NULL,
2846:                                        NULL,
2847:                                        MatGetOrdering_MPIAIJ};

2849: static PetscErrorCode MatStoreValues_MPIAIJ(Mat mat)
2850: {
2851:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2853:   PetscFunctionBegin;
2854:   PetscCall(MatStoreValues(aij->A));
2855:   PetscCall(MatStoreValues(aij->B));
2856:   PetscFunctionReturn(PETSC_SUCCESS);
2857: }

2859: static PetscErrorCode MatRetrieveValues_MPIAIJ(Mat mat)
2860: {
2861:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2863:   PetscFunctionBegin;
2864:   PetscCall(MatRetrieveValues(aij->A));
2865:   PetscCall(MatRetrieveValues(aij->B));
2866:   PetscFunctionReturn(PETSC_SUCCESS);
2867: }

2869: PetscErrorCode MatMPIAIJSetPreallocation_MPIAIJ(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
2870: {
2871:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2872:   PetscMPIInt size;

2874:   PetscFunctionBegin;
2875:   if (B->hash_active) {
2876:     B->ops[0]      = b->cops;
2877:     B->hash_active = PETSC_FALSE;
2878:   }
2879:   PetscCall(PetscLayoutSetUp(B->rmap));
2880:   PetscCall(PetscLayoutSetUp(B->cmap));

2882: #if PetscDefined(USE_CTABLE)
2883:   PetscCall(PetscHMapIDestroy(&b->colmap));
2884: #else
2885:   PetscCall(PetscFree(b->colmap));
2886: #endif
2887:   PetscCall(PetscFree(b->garray));
2888:   PetscCall(VecDestroy(&b->lvec));
2889:   PetscCall(VecScatterDestroy(&b->Mvctx));

2891:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

2893:   MatSeqXAIJGetOptions_Private(b->B);
2894:   PetscCall(MatDestroy(&b->B));
2895:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->B));
2896:   PetscCall(MatSetSizes(b->B, B->rmap->n, size > 1 ? B->cmap->N : 0, B->rmap->n, size > 1 ? B->cmap->N : 0));
2897:   PetscCall(MatSetBlockSizesFromMats(b->B, B, B));
2898:   PetscCall(MatSetType(b->B, MATSEQAIJ));
2899:   MatSeqXAIJRestoreOptions_Private(b->B);

2901:   MatSeqXAIJGetOptions_Private(b->A);
2902:   PetscCall(MatDestroy(&b->A));
2903:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->A));
2904:   PetscCall(MatSetSizes(b->A, B->rmap->n, B->cmap->n, B->rmap->n, B->cmap->n));
2905:   PetscCall(MatSetBlockSizesFromMats(b->A, B, B));
2906:   PetscCall(MatSetType(b->A, MATSEQAIJ));
2907:   MatSeqXAIJRestoreOptions_Private(b->A);

2909:   PetscCall(MatSeqAIJSetPreallocation(b->A, d_nz, d_nnz));
2910:   PetscCall(MatSeqAIJSetPreallocation(b->B, o_nz, o_nnz));
2911:   B->preallocated  = PETSC_TRUE;
2912:   B->was_assembled = PETSC_FALSE;
2913:   B->assembled     = PETSC_FALSE;
2914:   PetscFunctionReturn(PETSC_SUCCESS);
2915: }

2917: static PetscErrorCode MatResetPreallocation_MPIAIJ(Mat B)
2918: {
2919:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2920:   PetscBool   ondiagreset, offdiagreset, memoryreset;

2922:   PetscFunctionBegin;
2924:   PetscCheck(B->insertmode == NOT_SET_VALUES, PETSC_COMM_SELF, PETSC_ERR_SUP, "Cannot reset preallocation after setting some values but not yet calling MatAssemblyBegin()/MatAssemblyEnd()");
2925:   if (B->num_ass == 0) PetscFunctionReturn(PETSC_SUCCESS);

2927:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->A, &ondiagreset));
2928:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->B, &offdiagreset));
2929:   memoryreset = (PetscBool)(ondiagreset || offdiagreset);
2930:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &memoryreset, 1, MPI_C_BOOL, MPI_LOR, PetscObjectComm((PetscObject)B)));
2931:   if (!memoryreset) PetscFunctionReturn(PETSC_SUCCESS);

2933:   PetscCall(PetscLayoutSetUp(B->rmap));
2934:   PetscCall(PetscLayoutSetUp(B->cmap));
2935:   PetscCheck(B->assembled || B->was_assembled, PetscObjectComm((PetscObject)B), PETSC_ERR_ARG_WRONGSTATE, "Should not need to reset preallocation if the matrix was never assembled");
2936:   PetscCall(MatDisAssemble_MPIAIJ(B, PETSC_TRUE));
2937:   PetscCall(VecScatterDestroy(&b->Mvctx));

2939:   B->preallocated  = PETSC_TRUE;
2940:   B->was_assembled = PETSC_FALSE;
2941:   B->assembled     = PETSC_FALSE;
2942:   /* Log that the state of this object has changed; this will help guarantee that preconditioners get re-setup */
2943:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2944:   PetscFunctionReturn(PETSC_SUCCESS);
2945: }

2947: PetscErrorCode MatDuplicate_MPIAIJ(Mat matin, MatDuplicateOption cpvalues, Mat *newmat)
2948: {
2949:   Mat         mat;
2950:   Mat_MPIAIJ *a, *oldmat = (Mat_MPIAIJ *)matin->data;

2952:   PetscFunctionBegin;
2953:   *newmat = NULL;
2954:   PetscCall(MatCreate(PetscObjectComm((PetscObject)matin), &mat));
2955:   PetscCall(MatSetSizes(mat, matin->rmap->n, matin->cmap->n, matin->rmap->N, matin->cmap->N));
2956:   PetscCall(MatSetBlockSizesFromMats(mat, matin, matin));
2957:   PetscCall(MatSetType(mat, ((PetscObject)matin)->type_name));
2958:   a = (Mat_MPIAIJ *)mat->data;

2960:   mat->factortype = matin->factortype;
2961:   mat->assembled  = matin->assembled;
2962:   mat->insertmode = NOT_SET_VALUES;

2964:   a->size         = oldmat->size;
2965:   a->rank         = oldmat->rank;
2966:   a->donotstash   = oldmat->donotstash;
2967:   a->roworiented  = oldmat->roworiented;
2968:   a->rowindices   = NULL;
2969:   a->rowvalues    = NULL;
2970:   a->getrowactive = PETSC_FALSE;

2972:   PetscCall(PetscLayoutReference(matin->rmap, &mat->rmap));
2973:   PetscCall(PetscLayoutReference(matin->cmap, &mat->cmap));
2974:   if (matin->hash_active) PetscCall(MatSetUp(mat));
2975:   else {
2976:     mat->preallocated = matin->preallocated;
2977:     if (oldmat->colmap) {
2978: #if PetscDefined(USE_CTABLE)
2979:       PetscCall(PetscHMapIDuplicate(oldmat->colmap, &a->colmap));
2980: #else
2981:       PetscCall(PetscMalloc1(mat->cmap->N, &a->colmap));
2982:       PetscCall(PetscArraycpy(a->colmap, oldmat->colmap, mat->cmap->N));
2983: #endif
2984:     } else a->colmap = NULL;
2985:     if (oldmat->garray) {
2986:       PetscInt len;
2987:       len = oldmat->B->cmap->n;
2988:       PetscCall(PetscMalloc1(len, &a->garray));
2989:       if (len) PetscCall(PetscArraycpy(a->garray, oldmat->garray, len));
2990:     } else a->garray = NULL;

2992:     /* It may happen MatDuplicate is called with a non-assembled matrix
2993:       In fact, MatDuplicate only requires the matrix to be preallocated
2994:       This may happen inside a DMCreateMatrix_Shell */
2995:     if (oldmat->lvec) PetscCall(VecDuplicate(oldmat->lvec, &a->lvec));
2996:     if (oldmat->Mvctx) {
2997:       a->Mvctx = oldmat->Mvctx;
2998:       PetscCall(PetscObjectReference((PetscObject)oldmat->Mvctx));
2999:     }
3000:     PetscCall(MatDuplicate(oldmat->A, cpvalues, &a->A));
3001:     PetscCall(MatDuplicate(oldmat->B, cpvalues, &a->B));
3002:   }
3003:   PetscCall(PetscFunctionListDuplicate(((PetscObject)matin)->qlist, &((PetscObject)mat)->qlist));
3004:   *newmat = mat;
3005:   PetscFunctionReturn(PETSC_SUCCESS);
3006: }

3008: PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3009: {
3010:   PetscBool isbinary, ishdf5;

3012:   PetscFunctionBegin;
3015:   /* force binary viewer to load .info file if it has not yet done so */
3016:   PetscCall(PetscViewerSetUp(viewer));
3017:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
3018:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
3019:   if (isbinary) {
3020:     PetscCall(MatLoad_MPIAIJ_Binary(newMat, viewer));
3021:   } else if (ishdf5) {
3022: #if PetscDefined(HAVE_HDF5)
3023:     PetscCall(MatLoad_AIJ_HDF5(newMat, viewer));
3024: #else
3025:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
3026: #endif
3027:   } else {
3028:     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);
3029:   }
3030:   PetscFunctionReturn(PETSC_SUCCESS);
3031: }

3033: PetscErrorCode MatLoad_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
3034: {
3035:   PetscInt     header[4], M, N, m, nz, rows, cols, sum, i;
3036:   PetscInt    *rowidxs, *colidxs;
3037:   PetscScalar *matvals;

3039:   PetscFunctionBegin;
3040:   PetscCall(PetscViewerSetUp(viewer));

3042:   /* read in matrix header */
3043:   PetscCall(PetscViewerBinaryRead(viewer, header, 4, NULL, PETSC_INT));
3044:   PetscCheck(header[0] == MAT_FILE_CLASSID, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Not a matrix object in file");
3045:   M  = header[1];
3046:   N  = header[2];
3047:   nz = header[3];
3048:   PetscCheck(M >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix row size (%" PetscInt_FMT ") in file is negative", M);
3049:   PetscCheck(N >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix column size (%" PetscInt_FMT ") in file is negative", N);
3050:   PetscCheck(nz >= 0, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix stored in special format on disk, cannot load as MPIAIJ");

3052:   /* set block sizes from the viewer's .info file */
3053:   PetscCall(MatLoad_Binary_BlockSizes(mat, viewer));
3054:   /* set global sizes if not set already */
3055:   if (mat->rmap->N < 0) mat->rmap->N = M;
3056:   if (mat->cmap->N < 0) mat->cmap->N = N;
3057:   PetscCall(PetscLayoutSetUp(mat->rmap));
3058:   PetscCall(PetscLayoutSetUp(mat->cmap));

3060:   /* check if the matrix sizes are correct */
3061:   PetscCall(MatGetSize(mat, &rows, &cols));
3062:   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);

3064:   /* read in row lengths and build row indices */
3065:   PetscCall(MatGetLocalSize(mat, &m, NULL));
3066:   PetscCall(PetscMalloc1(m + 1, &rowidxs));
3067:   PetscCall(PetscViewerBinaryReadAll(viewer, rowidxs + 1, m, PETSC_DECIDE, M, PETSC_INT));
3068:   rowidxs[0] = 0;
3069:   for (i = 0; i < m; i++) rowidxs[i + 1] += rowidxs[i];
3070:   if (nz != PETSC_INT_MAX) {
3071:     PetscCallMPI(MPIU_Allreduce(&rowidxs[m], &sum, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)viewer)));
3072:     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);
3073:   }

3075:   /* read in column indices and matrix values */
3076:   PetscCall(PetscMalloc2(rowidxs[m], &colidxs, rowidxs[m], &matvals));
3077:   PetscCall(PetscViewerBinaryReadAll(viewer, colidxs, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
3078:   PetscCall(PetscViewerBinaryReadAll(viewer, matvals, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
3079:   /* store matrix indices and values */
3080:   PetscCall(MatMPIAIJSetPreallocationCSR(mat, rowidxs, colidxs, matvals));
3081:   PetscCall(PetscFree(rowidxs));
3082:   PetscCall(PetscFree2(colidxs, matvals));
3083:   PetscFunctionReturn(PETSC_SUCCESS);
3084: }

3086: /* Not scalable because of ISAllGather() unless getting all columns. */
3087: static PetscErrorCode ISGetSeqIS_Private(Mat mat, IS iscol, IS *isseq)
3088: {
3089:   IS          iscol_local;
3090:   PetscBool   isstride;
3091:   PetscMPIInt gisstride = 0;

3093:   PetscFunctionBegin;
3094:   /* check if we are grabbing all columns*/
3095:   PetscCall(PetscObjectTypeCompare((PetscObject)iscol, ISSTRIDE, &isstride));

3097:   if (isstride) {
3098:     PetscInt start, len, mstart, mlen;
3099:     PetscCall(ISStrideGetInfo(iscol, &start, NULL));
3100:     PetscCall(ISGetLocalSize(iscol, &len));
3101:     PetscCall(MatGetOwnershipRangeColumn(mat, &mstart, &mlen));
3102:     if (mstart == start && mlen - mstart == len) gisstride = 1;
3103:   }

3105:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &gisstride, 1, MPI_INT, MPI_MIN, PetscObjectComm((PetscObject)mat)));
3106:   if (gisstride) {
3107:     PetscInt N;
3108:     PetscCall(MatGetSize(mat, NULL, &N));
3109:     PetscCall(ISCreateStride(PETSC_COMM_SELF, N, 0, 1, &iscol_local));
3110:     PetscCall(ISSetIdentity(iscol_local));
3111:     PetscCall(PetscInfo(mat, "Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n"));
3112:   } else {
3113:     PetscInt cbs;
3114:     PetscCall(ISGetBlockSize(iscol, &cbs));
3115:     PetscCall(ISAllGather(iscol, &iscol_local));
3116:     PetscCall(ISSetBlockSize(iscol_local, cbs));
3117:   }

3119:   *isseq = iscol_local;
3120:   PetscFunctionReturn(PETSC_SUCCESS);
3121: }

3123: /*
3124:  Used by MatCreateSubMatrix_MPIAIJ_SameRowColDist() to avoid ISAllGather() and global size of iscol_local
3125:  (see MatCreateSubMatrix_MPIAIJ_nonscalable)

3127:  Input Parameters:
3128: +   mat - matrix
3129: .   isrow - parallel row index set; its local indices are a subset of local columns of `mat`,
3130:            i.e., mat->rstart <= isrow[i] < mat->rend
3131: -   iscol - parallel column index set; its local indices are a subset of local columns of `mat`,
3132:            i.e., mat->cstart <= iscol[i] < mat->cend

3134:  Output Parameters:
3135: +   isrow_d - sequential row index set for retrieving mat->A
3136: .   iscol_d - sequential  column index set for retrieving mat->A
3137: .   iscol_o - sequential column index set for retrieving mat->B
3138: -   garray - column map; garray[i] indicates global location of iscol_o[i] in `iscol`
3139:  */
3140: static PetscErrorCode ISGetSeqIS_SameColDist_Private(Mat mat, IS isrow, IS iscol, IS *isrow_d, IS *iscol_d, IS *iscol_o, PetscInt *garray[])
3141: {
3142:   Vec             x, cmap;
3143:   const PetscInt *is_idx;
3144:   PetscScalar    *xarray, *cmaparray;
3145:   PetscInt        ncols, isstart, *idx, m, rstart, *cmap1, count;
3146:   Mat_MPIAIJ     *a    = (Mat_MPIAIJ *)mat->data;
3147:   Mat             B    = a->B;
3148:   Vec             lvec = a->lvec, lcmap;
3149:   PetscInt        i, cstart, cend, Bn = B->cmap->N;
3150:   MPI_Comm        comm;
3151:   VecScatter      Mvctx = a->Mvctx;

3153:   PetscFunctionBegin;
3154:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3155:   PetscCall(ISGetLocalSize(iscol, &ncols));

3157:   /* (1) iscol is a sub-column vector of mat, pad it with '-1.' to form a full vector x */
3158:   PetscCall(MatCreateVecs(mat, &x, NULL));
3159:   PetscCall(VecSet(x, -1.0));
3160:   PetscCall(VecDuplicate(x, &cmap));
3161:   PetscCall(VecSet(cmap, -1.0));

3163:   /* Get start indices */
3164:   PetscCallMPI(MPI_Scan(&ncols, &isstart, 1, MPIU_INT, MPI_SUM, comm));
3165:   isstart -= ncols;
3166:   PetscCall(MatGetOwnershipRangeColumn(mat, &cstart, &cend));

3168:   PetscCall(ISGetIndices(iscol, &is_idx));
3169:   PetscCall(VecGetArray(x, &xarray));
3170:   PetscCall(VecGetArray(cmap, &cmaparray));
3171:   PetscCall(PetscMalloc1(ncols, &idx));
3172:   for (i = 0; i < ncols; i++) {
3173:     xarray[is_idx[i] - cstart]    = (PetscScalar)is_idx[i];
3174:     cmaparray[is_idx[i] - cstart] = i + isstart;        /* global index of iscol[i] */
3175:     idx[i]                        = is_idx[i] - cstart; /* local index of iscol[i]  */
3176:   }
3177:   PetscCall(VecRestoreArray(x, &xarray));
3178:   PetscCall(VecRestoreArray(cmap, &cmaparray));
3179:   PetscCall(ISRestoreIndices(iscol, &is_idx));

3181:   /* Get iscol_d */
3182:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, iscol_d));
3183:   PetscCall(ISGetBlockSize(iscol, &i));
3184:   PetscCall(ISSetBlockSize(*iscol_d, i));

3186:   /* Get isrow_d */
3187:   PetscCall(ISGetLocalSize(isrow, &m));
3188:   rstart = mat->rmap->rstart;
3189:   PetscCall(PetscMalloc1(m, &idx));
3190:   PetscCall(ISGetIndices(isrow, &is_idx));
3191:   for (i = 0; i < m; i++) idx[i] = is_idx[i] - rstart;
3192:   PetscCall(ISRestoreIndices(isrow, &is_idx));

3194:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx, PETSC_OWN_POINTER, isrow_d));
3195:   PetscCall(ISGetBlockSize(isrow, &i));
3196:   PetscCall(ISSetBlockSize(*isrow_d, i));

3198:   /* (2) Scatter x and cmap using aij->Mvctx to get their off-process portions (see MatMult_MPIAIJ) */
3199:   PetscCall(VecScatterBegin(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));
3200:   PetscCall(VecScatterEnd(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));

3202:   PetscCall(VecDuplicate(lvec, &lcmap));

3204:   PetscCall(VecScatterBegin(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));
3205:   PetscCall(VecScatterEnd(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));

3207:   /* (3) create sequential iscol_o (a subset of iscol) and isgarray */
3208:   /* off-process column indices */
3209:   count = 0;
3210:   PetscCall(PetscMalloc1(Bn, &idx));
3211:   PetscCall(PetscMalloc1(Bn, &cmap1));

3213:   PetscCall(VecGetArray(lvec, &xarray));
3214:   PetscCall(VecGetArray(lcmap, &cmaparray));
3215:   for (i = 0; i < Bn; i++) {
3216:     if (PetscRealPart(xarray[i]) > -1.0) {
3217:       idx[count]   = i;                                     /* local column index in off-diagonal part B */
3218:       cmap1[count] = (PetscInt)PetscRealPart(cmaparray[i]); /* column index in submat */
3219:       count++;
3220:     }
3221:   }
3222:   PetscCall(VecRestoreArray(lvec, &xarray));
3223:   PetscCall(VecRestoreArray(lcmap, &cmaparray));

3225:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_COPY_VALUES, iscol_o));
3226:   /* cannot ensure iscol_o has same blocksize as iscol! */

3228:   PetscCall(PetscFree(idx));
3229:   *garray = cmap1;

3231:   PetscCall(VecDestroy(&x));
3232:   PetscCall(VecDestroy(&cmap));
3233:   PetscCall(VecDestroy(&lcmap));
3234:   PetscFunctionReturn(PETSC_SUCCESS);
3235: }

3237: /* isrow and iscol have same processor distribution as mat, output *submat is a submatrix of local mat */
3238: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowColDist(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *submat)
3239: {
3240:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)mat->data, *asub;
3241:   Mat         M = NULL;
3242:   MPI_Comm    comm;
3243:   IS          iscol_d, isrow_d, iscol_o;
3244:   Mat         Asub = NULL, Bsub = NULL;
3245:   PetscInt    n, count, M_size, N_size;

3247:   PetscFunctionBegin;
3248:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));

3250:   if (call == MAT_REUSE_MATRIX) {
3251:     /* Retrieve isrow_d, iscol_d and iscol_o from submat */
3252:     PetscCall(PetscObjectQuery((PetscObject)*submat, "isrow_d", (PetscObject *)&isrow_d));
3253:     PetscCheck(isrow_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "isrow_d passed in was not used before, cannot reuse");

3255:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_d", (PetscObject *)&iscol_d));
3256:     PetscCheck(iscol_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_d passed in was not used before, cannot reuse");

3258:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_o", (PetscObject *)&iscol_o));
3259:     PetscCheck(iscol_o, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_o passed in was not used before, cannot reuse");

3261:     /* Update diagonal and off-diagonal portions of submat */
3262:     asub = (Mat_MPIAIJ *)(*submat)->data;
3263:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->A));
3264:     PetscCall(ISGetLocalSize(iscol_o, &n));
3265:     if (n) PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->B));
3266:     PetscCall(MatAssemblyBegin(*submat, MAT_FINAL_ASSEMBLY));
3267:     PetscCall(MatAssemblyEnd(*submat, MAT_FINAL_ASSEMBLY));

3269:   } else { /* call == MAT_INITIAL_MATRIX) */
3270:     PetscInt *garray, *garray_compact;
3271:     PetscInt  BsubN;

3273:     /* Create isrow_d, iscol_d, iscol_o and isgarray (replace isgarray with array?) */
3274:     PetscCall(ISGetSeqIS_SameColDist_Private(mat, isrow, iscol, &isrow_d, &iscol_d, &iscol_o, &garray));

3276:     /* Create local submatrices Asub and Bsub */
3277:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Asub));
3278:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Bsub));

3280:     // Compact garray so its not of size Bn
3281:     PetscCall(ISGetSize(iscol_o, &count));
3282:     PetscCall(PetscMalloc1(count, &garray_compact));
3283:     PetscCall(PetscArraycpy(garray_compact, garray, count));

3285:     /* Create submatrix M */
3286:     PetscCall(ISGetSize(isrow, &M_size));
3287:     PetscCall(ISGetSize(iscol, &N_size));
3288:     PetscCall(MatCreateMPIAIJWithSeqAIJ(comm, M_size, N_size, Asub, Bsub, garray_compact, &M));

3290:     /* If Bsub has empty columns, compress iscol_o such that it will retrieve condensed Bsub from a->B during reuse */
3291:     asub = (Mat_MPIAIJ *)M->data;

3293:     PetscCall(ISGetLocalSize(iscol_o, &BsubN));
3294:     n = asub->B->cmap->N;
3295:     if (BsubN > n) {
3296:       /* This case can be tested using ~petsc/src/tao/bound/tutorials/runplate2_3 */
3297:       const PetscInt *idx;
3298:       PetscInt        i, j, *idx_new, *subgarray = asub->garray;
3299:       PetscCall(PetscInfo(M, "submatrix Bn %" PetscInt_FMT " != BsubN %" PetscInt_FMT ", update iscol_o\n", n, BsubN));

3301:       PetscCall(PetscMalloc1(n, &idx_new));
3302:       j = 0;
3303:       PetscCall(ISGetIndices(iscol_o, &idx));
3304:       for (i = 0; i < n; i++) {
3305:         if (j >= BsubN) break;
3306:         while (subgarray[i] > garray[j]) j++;

3308:         PetscCheck(subgarray[i] == garray[j], PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "subgarray[%" PetscInt_FMT "]=%" PetscInt_FMT " cannot < garray[%" PetscInt_FMT "]=%" PetscInt_FMT, i, subgarray[i], j, garray[j]);
3309:         idx_new[i] = idx[j++];
3310:       }
3311:       PetscCall(ISRestoreIndices(iscol_o, &idx));

3313:       PetscCall(ISDestroy(&iscol_o));
3314:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, idx_new, PETSC_OWN_POINTER, &iscol_o));

3316:     } else PetscCheck(BsubN >= n, 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);

3318:     PetscCall(PetscFree(garray));
3319:     *submat = M;

3321:     /* Save isrow_d, iscol_d and iscol_o used in processor for next request */
3322:     PetscCall(PetscObjectCompose((PetscObject)M, "isrow_d", (PetscObject)isrow_d));
3323:     PetscCall(ISDestroy(&isrow_d));

3325:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_d", (PetscObject)iscol_d));
3326:     PetscCall(ISDestroy(&iscol_d));

3328:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_o", (PetscObject)iscol_o));
3329:     PetscCall(ISDestroy(&iscol_o));
3330:   }
3331:   PetscFunctionReturn(PETSC_SUCCESS);
3332: }

3334: PetscErrorCode MatCreateSubMatrix_MPIAIJ(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *newmat)
3335: {
3336:   IS        iscol_local = NULL, isrow_d;
3337:   PetscInt  csize;
3338:   PetscInt  n, i, j, start, end;
3339:   PetscBool sameRowDist = PETSC_FALSE, tsameDist[2];
3340:   MPI_Comm  comm;

3342:   PetscFunctionBegin;
3343:   /* If isrow has same processor distribution as mat,
3344:      call MatCreateSubMatrix_MPIAIJ_SameRowDist() to avoid using a hash table with global size of iscol */
3345:   if (call == MAT_REUSE_MATRIX) {
3346:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "isrow_d", (PetscObject *)&isrow_d));
3347:     if (isrow_d) {
3348:       sameRowDist  = PETSC_TRUE;
3349:       tsameDist[1] = PETSC_TRUE; /* sameColDist */
3350:     } else {
3351:       PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_local));
3352:       if (iscol_local) {
3353:         sameRowDist  = PETSC_TRUE;
3354:         tsameDist[1] = PETSC_FALSE; /* !sameColDist */
3355:       }
3356:     }
3357:   } else {
3358:     /* Check if isrow has same processor distribution as mat */
3359:     tsameDist[0] = PETSC_FALSE;
3360:     PetscCall(ISGetLocalSize(isrow, &n));
3361:     if (!n) {
3362:       tsameDist[0] = PETSC_TRUE;
3363:     } else {
3364:       PetscCall(ISGetMinMax(isrow, &i, &j));
3365:       PetscCall(MatGetOwnershipRange(mat, &start, &end));
3366:       if (i >= start && j < end) tsameDist[0] = PETSC_TRUE;
3367:     }

3369:     /* Check if iscol has same processor distribution as mat */
3370:     tsameDist[1] = PETSC_FALSE;
3371:     PetscCall(ISGetLocalSize(iscol, &n));
3372:     if (!n) {
3373:       tsameDist[1] = PETSC_TRUE;
3374:     } else {
3375:       PetscCall(ISGetMinMax(iscol, &i, &j));
3376:       PetscCall(MatGetOwnershipRangeColumn(mat, &start, &end));
3377:       if (i >= start && j < end) tsameDist[1] = PETSC_TRUE;
3378:     }

3380:     PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3381:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, tsameDist, 2, MPI_C_BOOL, MPI_LAND, comm));
3382:     sameRowDist = tsameDist[0];
3383:   }

3385:   if (sameRowDist) {
3386:     if (tsameDist[1]) { /* sameRowDist & sameColDist */
3387:       /* isrow and iscol have same processor distribution as mat */
3388:       PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowColDist(mat, isrow, iscol, call, newmat));
3389:       PetscFunctionReturn(PETSC_SUCCESS);
3390:     } else { /* sameRowDist */
3391:       /* isrow has same processor distribution as mat */
3392:       if (call == MAT_INITIAL_MATRIX) {
3393:         PetscBool sorted;
3394:         PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3395:         PetscCall(ISGetLocalSize(iscol_local, &n)); /* local size of iscol_local = global columns of newmat */
3396:         PetscCall(ISGetSize(iscol, &i));
3397:         PetscCheck(n == i, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "n %" PetscInt_FMT " != size of iscol %" PetscInt_FMT, n, i);

3399:         PetscCall(ISSorted(iscol_local, &sorted));
3400:         if (sorted) {
3401:           /* MatCreateSubMatrix_MPIAIJ_SameRowDist() requires iscol_local be sorted; it can have duplicate indices */
3402:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, iscol_local, MAT_INITIAL_MATRIX, newmat));
3403:           PetscFunctionReturn(PETSC_SUCCESS);
3404:         }
3405:       } else { /* call == MAT_REUSE_MATRIX */
3406:         IS iscol_sub;
3407:         PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3408:         if (iscol_sub) {
3409:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, NULL, call, newmat));
3410:           PetscFunctionReturn(PETSC_SUCCESS);
3411:         }
3412:       }
3413:     }
3414:   }

3416:   /* General case: iscol -> iscol_local which has global size of iscol */
3417:   if (call == MAT_REUSE_MATRIX) {
3418:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "ISAllGather", (PetscObject *)&iscol_local));
3419:     PetscCheck(iscol_local, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3420:   } else {
3421:     if (!iscol_local) PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3422:   }

3424:   PetscCall(ISGetLocalSize(iscol, &csize));
3425:   PetscCall(MatCreateSubMatrix_MPIAIJ_nonscalable(mat, isrow, iscol_local, csize, call, newmat));

3427:   if (call == MAT_INITIAL_MATRIX) {
3428:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3429:     PetscCall(ISDestroy(&iscol_local));
3430:   }
3431:   PetscFunctionReturn(PETSC_SUCCESS);
3432: }

3434: /*@
3435:   MatCreateMPIAIJWithSeqAIJ - creates a `MATMPIAIJ` matrix using `MATSEQAIJ` matrices that contain the "diagonal"
3436:   and "off-diagonal" part of the matrix in CSR format.

3438:   Collective

3440:   Input Parameters:
3441: + comm   - MPI communicator
3442: . M      - the global row size
3443: . N      - the global column size
3444: . A      - "diagonal" portion of matrix
3445: . B      - if garray is `NULL`, B should be the offdiag matrix using global col ids and of size N - if garray is not `NULL`, B should be the offdiag matrix using local col ids and of size garray
3446: - garray - either `NULL` or the global index of `B` columns. If not `NULL`, it should be allocated by `PetscMalloc1()` and will be owned by `mat` thereafter.

3448:   Output Parameter:
3449: . mat - the matrix, with input `A` as its local diagonal matrix

3451:   Level: advanced

3453:   Notes:
3454:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix.

3456:   `A` and `B` becomes part of output mat. The user cannot use `A` and `B` anymore.

3458:   If `garray` is `NULL`, `B` will be compacted to use local indices. In this sense, `B`'s sparsity pattern (nonzerostate) will be changed. If `B` is a device matrix, we need to somehow also update
3459:   `B`'s copy on device.  We do so by increasing `B`'s nonzerostate. In use of `B` on device, device matrix types should detect this change (ref. internal routines `MatSeqAIJCUSPARSECopyToGPU()` or
3460:   `MatAssemblyEnd_SeqAIJKokkos()`) and will just destroy and then recreate the device copy of `B`. It is not optimal, but is easy to implement and less hacky. To avoid this overhead, try to compute `garray`
3461:   yourself, see algorithms in the private function `MatSetUpMultiply_MPIAIJ()`.

3463:   The `NULL`-ness of `garray` doesn't need to be collective, in other words, `garray` can be `NULL` on some processes while not on others.

3465: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJWithSplitArrays()`
3466: @*/
3467: PetscErrorCode MatCreateMPIAIJWithSeqAIJ(MPI_Comm comm, PetscInt M, PetscInt N, Mat A, Mat B, PetscInt *garray, Mat *mat)
3468: {
3469:   PetscInt    m, n;
3470:   MatType     mpi_mat_type;
3471:   Mat_MPIAIJ *mpiaij;
3472:   Mat         C;

3474:   PetscFunctionBegin;
3475:   PetscCall(MatCreate(comm, &C));
3476:   PetscCall(MatGetSize(A, &m, &n));
3477:   PetscCheck(m == B->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Am %" PetscInt_FMT " != Bm %" PetscInt_FMT, m, B->rmap->N);
3478:   PetscCheck(A->rmap->bs == 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);

3480:   PetscCall(MatSetSizes(C, m, n, M, N));
3481:   /* Determine the type of MPI matrix that should be created from the type of matrix A, which holds the "diagonal" portion. */
3482:   PetscCall(MatGetMPIMatType_Private(A, &mpi_mat_type));
3483:   PetscCall(MatSetType(C, mpi_mat_type));
3484:   if (!garray) {
3485:     const PetscScalar *ba;

3487:     B->nonzerostate++;
3488:     PetscCall(MatSeqAIJGetArrayRead(B, &ba)); /* Since we will destroy B's device copy, we need to make sure the host copy is up to date */
3489:     PetscCall(MatSeqAIJRestoreArrayRead(B, &ba));
3490:   }

3492:   PetscCall(MatSetBlockSizes(C, A->rmap->bs, A->cmap->bs));
3493:   PetscCall(PetscLayoutSetUp(C->rmap));
3494:   PetscCall(PetscLayoutSetUp(C->cmap));

3496:   mpiaij              = (Mat_MPIAIJ *)C->data;
3497:   mpiaij->A           = A;
3498:   mpiaij->B           = B;
3499:   mpiaij->garray      = garray;
3500:   C->preallocated     = PETSC_TRUE;
3501:   C->nooffprocentries = PETSC_TRUE; /* See MatAssemblyBegin_MPIAIJ. In effect, making MatAssemblyBegin a nop */

3503:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
3504:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
3505:   /* MatAssemblyEnd is critical here. It sets mat->offloadmask according to A and B's, and
3506:    also gets mpiaij->B compacted (if garray is NULL), with its col ids and size reduced
3507:    */
3508:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
3509:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
3510:   PetscCall(MatSetOption(C, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3511:   *mat = C;
3512:   PetscFunctionReturn(PETSC_SUCCESS);
3513: }

3515: extern PetscErrorCode MatCreateSubMatrices_MPIAIJ_SingleIS_Local(Mat, PetscInt, const IS[], const IS[], MatReuse, PetscBool, Mat *);

3517: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowDist(Mat mat, IS isrow, IS iscol, IS iscol_local, MatReuse call, Mat *newmat)
3518: {
3519:   PetscInt        i, m, n, rstart, row, rend, nz, j, bs, cbs;
3520:   PetscInt       *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3521:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)mat->data;
3522:   Mat             M, Msub, B = a->B;
3523:   MatScalar      *aa;
3524:   Mat_SeqAIJ     *aij;
3525:   PetscInt       *garray = a->garray, *colsub, Ncols;
3526:   PetscInt        count, Bn = B->cmap->N, cstart = mat->cmap->rstart, cend = mat->cmap->rend;
3527:   IS              iscol_sub, iscmap;
3528:   const PetscInt *is_idx, *cmap;
3529:   PetscBool       allcolumns = PETSC_FALSE;
3530:   MPI_Comm        comm;

3532:   PetscFunctionBegin;
3533:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3534:   if (call == MAT_REUSE_MATRIX) {
3535:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3536:     PetscCheck(iscol_sub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "SubIScol passed in was not used before, cannot reuse");
3537:     PetscCall(ISGetLocalSize(iscol_sub, &count));

3539:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "Subcmap", (PetscObject *)&iscmap));
3540:     PetscCheck(iscmap, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Subcmap passed in was not used before, cannot reuse");

3542:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Msub));
3543:     PetscCheck(Msub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");

3545:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_REUSE_MATRIX, PETSC_FALSE, &Msub));

3547:   } else { /* call == MAT_INITIAL_MATRIX) */
3548:     PetscBool flg;

3550:     PetscCall(ISGetLocalSize(iscol, &n));
3551:     PetscCall(ISGetSize(iscol, &Ncols));

3553:     /* (1) iscol -> nonscalable iscol_local */
3554:     /* Check for special case: each processor gets entire matrix columns */
3555:     PetscCall(ISIdentity(iscol_local, &flg));
3556:     if (flg && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3557:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
3558:     if (allcolumns) {
3559:       iscol_sub = iscol_local;
3560:       PetscCall(PetscObjectReference((PetscObject)iscol_local));
3561:       PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &iscmap));

3563:     } else {
3564:       /* (2) iscol_local -> iscol_sub and iscmap. Implementation below requires iscol_local be sorted, it can have duplicate indices */
3565:       PetscInt *idx, *cmap1, k;
3566:       PetscCall(PetscMalloc1(Ncols, &idx));
3567:       PetscCall(PetscMalloc1(Ncols, &cmap1));
3568:       PetscCall(ISGetIndices(iscol_local, &is_idx));
3569:       count = 0;
3570:       k     = 0;
3571:       for (i = 0; i < Ncols; i++) {
3572:         j = is_idx[i];
3573:         if (j >= cstart && j < cend) {
3574:           /* diagonal part of mat */
3575:           idx[count]     = j;
3576:           cmap1[count++] = i; /* column index in submat */
3577:         } else if (Bn) {
3578:           /* off-diagonal part of mat */
3579:           if (j == garray[k]) {
3580:             idx[count]     = j;
3581:             cmap1[count++] = i; /* column index in submat */
3582:           } else if (j > garray[k]) {
3583:             while (j > garray[k] && k < Bn - 1) k++;
3584:             if (j == garray[k]) {
3585:               idx[count]     = j;
3586:               cmap1[count++] = i; /* column index in submat */
3587:             }
3588:           }
3589:         }
3590:       }
3591:       PetscCall(ISRestoreIndices(iscol_local, &is_idx));

3593:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_OWN_POINTER, &iscol_sub));
3594:       PetscCall(ISGetBlockSize(iscol, &cbs));
3595:       PetscCall(ISSetBlockSize(iscol_sub, cbs));

3597:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)iscol_local), count, cmap1, PETSC_OWN_POINTER, &iscmap));
3598:     }

3600:     /* (3) Create sequential Msub */
3601:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_INITIAL_MATRIX, allcolumns, &Msub));
3602:   }

3604:   PetscCall(ISGetLocalSize(iscol_sub, &count));
3605:   aij = (Mat_SeqAIJ *)Msub->data;
3606:   ii  = aij->i;
3607:   PetscCall(ISGetIndices(iscmap, &cmap));

3609:   /*
3610:       m - number of local rows
3611:       Ncols - number of columns (same on all processors)
3612:       rstart - first row in new global matrix generated
3613:   */
3614:   PetscCall(MatGetSize(Msub, &m, NULL));

3616:   if (call == MAT_INITIAL_MATRIX) {
3617:     /* (4) Create parallel newmat */
3618:     PetscMPIInt rank, size;
3619:     PetscInt    csize;

3621:     PetscCallMPI(MPI_Comm_size(comm, &size));
3622:     PetscCallMPI(MPI_Comm_rank(comm, &rank));

3624:     /*
3625:         Determine the number of non-zeros in the diagonal and off-diagonal
3626:         portions of the matrix in order to do correct preallocation
3627:     */

3629:     /* first get start and end of "diagonal" columns */
3630:     PetscCall(ISGetLocalSize(iscol, &csize));
3631:     if (csize == PETSC_DECIDE) {
3632:       PetscCall(ISGetSize(isrow, &mglobal));
3633:       if (mglobal == Ncols) { /* square matrix */
3634:         nlocal = m;
3635:       } else {
3636:         nlocal = Ncols / size + ((Ncols % size) > rank);
3637:       }
3638:     } else {
3639:       nlocal = csize;
3640:     }
3641:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3642:     rstart = rend - nlocal;
3643:     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);

3645:     /* next, compute all the lengths */
3646:     jj = aij->j;
3647:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3648:     olens = dlens + m;
3649:     for (i = 0; i < m; i++) {
3650:       jend = ii[i + 1] - ii[i];
3651:       olen = 0;
3652:       dlen = 0;
3653:       for (j = 0; j < jend; j++) {
3654:         if (cmap[*jj] < rstart || cmap[*jj] >= rend) olen++;
3655:         else dlen++;
3656:         jj++;
3657:       }
3658:       olens[i] = olen;
3659:       dlens[i] = dlen;
3660:     }

3662:     PetscCall(ISGetBlockSize(isrow, &bs));
3663:     PetscCall(ISGetBlockSize(iscol, &cbs));

3665:     PetscCall(MatCreate(comm, &M));
3666:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, Ncols));
3667:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3668:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3669:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3670:     PetscCall(PetscFree(dlens));

3672:   } else { /* call == MAT_REUSE_MATRIX */
3673:     M = *newmat;
3674:     PetscCall(MatGetLocalSize(M, &i, NULL));
3675:     PetscCheck(i == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3676:     PetscCall(MatZeroEntries(M));
3677:     /*
3678:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3679:        rather than the slower MatSetValues().
3680:     */
3681:     M->was_assembled = PETSC_TRUE;
3682:     M->assembled     = PETSC_FALSE;
3683:   }

3685:   /* (5) Set values of Msub to *newmat */
3686:   PetscCall(PetscMalloc1(count, &colsub));
3687:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));

3689:   jj = aij->j;
3690:   PetscCall(MatSeqAIJGetArrayRead(Msub, (const PetscScalar **)&aa));
3691:   for (i = 0; i < m; i++) {
3692:     row = rstart + i;
3693:     nz  = ii[i + 1] - ii[i];
3694:     for (j = 0; j < nz; j++) colsub[j] = cmap[jj[j]];
3695:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, colsub, aa, INSERT_VALUES));
3696:     jj += nz;
3697:     aa += nz;
3698:   }
3699:   PetscCall(MatSeqAIJRestoreArrayRead(Msub, (const PetscScalar **)&aa));
3700:   PetscCall(ISRestoreIndices(iscmap, &cmap));

3702:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3703:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));

3705:   PetscCall(PetscFree(colsub));

3707:   /* save Msub, iscol_sub and iscmap used in processor for next request */
3708:   if (call == MAT_INITIAL_MATRIX) {
3709:     *newmat = M;
3710:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubMatrix", (PetscObject)Msub));
3711:     PetscCall(MatDestroy(&Msub));

3713:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubIScol", (PetscObject)iscol_sub));
3714:     PetscCall(ISDestroy(&iscol_sub));

3716:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "Subcmap", (PetscObject)iscmap));
3717:     PetscCall(ISDestroy(&iscmap));

3719:     if (iscol_local) {
3720:       PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3721:       PetscCall(ISDestroy(&iscol_local));
3722:     }
3723:   }
3724:   PetscFunctionReturn(PETSC_SUCCESS);
3725: }

3727: /*
3728:     Not great since it makes two copies of the submatrix, first an SeqAIJ
3729:   in local and then by concatenating the local matrices the end result.
3730:   Writing it directly would be much like MatCreateSubMatrices_MPIAIJ()

3732:   This requires a sequential iscol with all indices.
3733: */
3734: PetscErrorCode MatCreateSubMatrix_MPIAIJ_nonscalable(Mat mat, IS isrow, IS iscol, PetscInt csize, MatReuse call, Mat *newmat)
3735: {
3736:   PetscMPIInt rank, size;
3737:   PetscInt    i, m, n, rstart, row, rend, nz, *cwork, j, bs, cbs;
3738:   PetscInt   *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3739:   Mat         M, Mreuse;
3740:   MatScalar  *aa, *vwork;
3741:   MPI_Comm    comm;
3742:   Mat_SeqAIJ *aij;
3743:   PetscBool   colflag, allcolumns = PETSC_FALSE;

3745:   PetscFunctionBegin;
3746:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3747:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
3748:   PetscCallMPI(MPI_Comm_size(comm, &size));

3750:   /* Check for special case: each processor gets entire matrix columns */
3751:   PetscCall(ISIdentity(iscol, &colflag));
3752:   PetscCall(ISGetLocalSize(iscol, &n));
3753:   if (colflag && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3754:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));

3756:   if (call == MAT_REUSE_MATRIX) {
3757:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Mreuse));
3758:     PetscCheck(Mreuse, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3759:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_REUSE_MATRIX, allcolumns, &Mreuse));
3760:   } else {
3761:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, allcolumns, &Mreuse));
3762:   }

3764:   /*
3765:       m - number of local rows
3766:       n - number of columns (same on all processors)
3767:       rstart - first row in new global matrix generated
3768:   */
3769:   PetscCall(MatGetSize(Mreuse, &m, &n));
3770:   PetscCall(MatGetBlockSizes(Mreuse, &bs, &cbs));
3771:   if (call == MAT_INITIAL_MATRIX) {
3772:     aij = (Mat_SeqAIJ *)Mreuse->data;
3773:     ii  = aij->i;
3774:     jj  = aij->j;

3776:     /*
3777:         Determine the number of non-zeros in the diagonal and off-diagonal
3778:         portions of the matrix in order to do correct preallocation
3779:     */

3781:     /* first get start and end of "diagonal" columns */
3782:     if (csize == PETSC_DECIDE) {
3783:       PetscCall(ISGetSize(isrow, &mglobal));
3784:       if (mglobal == n) { /* square matrix */
3785:         nlocal = m;
3786:       } else {
3787:         nlocal = n / size + ((n % size) > rank);
3788:       }
3789:     } else {
3790:       nlocal = csize;
3791:     }
3792:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3793:     rstart = rend - nlocal;
3794:     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);

3796:     /* next, compute all the lengths */
3797:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3798:     olens = dlens + m;
3799:     for (i = 0; i < m; i++) {
3800:       jend = ii[i + 1] - ii[i];
3801:       olen = 0;
3802:       dlen = 0;
3803:       for (j = 0; j < jend; j++) {
3804:         if (*jj < rstart || *jj >= rend) olen++;
3805:         else dlen++;
3806:         jj++;
3807:       }
3808:       olens[i] = olen;
3809:       dlens[i] = dlen;
3810:     }
3811:     PetscCall(MatCreate(comm, &M));
3812:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, n));
3813:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3814:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3815:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3816:     PetscCall(PetscFree(dlens));
3817:   } else {
3818:     PetscInt ml, nl;

3820:     M = *newmat;
3821:     PetscCall(MatGetLocalSize(M, &ml, &nl));
3822:     PetscCheck(ml == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3823:     PetscCall(MatZeroEntries(M));
3824:     /*
3825:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3826:        rather than the slower MatSetValues().
3827:     */
3828:     M->was_assembled = PETSC_TRUE;
3829:     M->assembled     = PETSC_FALSE;
3830:   }
3831:   PetscCall(MatGetOwnershipRange(M, &rstart, &rend));
3832:   aij = (Mat_SeqAIJ *)Mreuse->data;
3833:   ii  = aij->i;
3834:   jj  = aij->j;

3836:   /* trigger copy to CPU if needed */
3837:   PetscCall(MatSeqAIJGetArrayRead(Mreuse, (const PetscScalar **)&aa));
3838:   for (i = 0; i < m; i++) {
3839:     row   = rstart + i;
3840:     nz    = ii[i + 1] - ii[i];
3841:     cwork = jj;
3842:     jj    = PetscSafePointerPlusOffset(jj, nz);
3843:     vwork = aa;
3844:     aa    = PetscSafePointerPlusOffset(aa, nz);
3845:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, cwork, vwork, INSERT_VALUES));
3846:   }
3847:   PetscCall(MatSeqAIJRestoreArrayRead(Mreuse, (const PetscScalar **)&aa));

3849:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3850:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
3851:   *newmat = M;

3853:   /* save submatrix used in processor for next request */
3854:   if (call == MAT_INITIAL_MATRIX) {
3855:     PetscCall(PetscObjectCompose((PetscObject)M, "SubMatrix", (PetscObject)Mreuse));
3856:     PetscCall(MatDestroy(&Mreuse));
3857:   }
3858:   PetscFunctionReturn(PETSC_SUCCESS);
3859: }

3861: static PetscErrorCode MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
3862: {
3863:   PetscInt        m, cstart, cend, j, nnz, i, d, *ld;
3864:   PetscInt       *d_nnz, *o_nnz, nnz_max = 0, rstart, ii, irstart;
3865:   const PetscInt *JJ;
3866:   PetscBool       nooffprocentries;
3867:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)B->data;

3869:   PetscFunctionBegin;
3870:   PetscCall(PetscLayoutSetUp(B->rmap));
3871:   PetscCall(PetscLayoutSetUp(B->cmap));
3872:   m       = B->rmap->n;
3873:   cstart  = B->cmap->rstart;
3874:   cend    = B->cmap->rend;
3875:   rstart  = B->rmap->rstart;
3876:   irstart = Ii[0];

3878:   PetscCall(PetscCalloc2(m, &d_nnz, m, &o_nnz));

3880:   if (PetscDefined(USE_DEBUG)) {
3881:     for (i = 0; i < m; i++) {
3882:       nnz = Ii[i + 1] - Ii[i];
3883:       JJ  = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3884:       PetscCheck(nnz >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local row %" PetscInt_FMT " has a negative %" PetscInt_FMT " number of columns", i, nnz);
3885:       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]);
3886:       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);
3887:     }
3888:   }

3890:   for (i = 0; i < m; i++) {
3891:     nnz     = Ii[i + 1] - Ii[i];
3892:     JJ      = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3893:     nnz_max = PetscMax(nnz_max, nnz);
3894:     d       = 0;
3895:     for (j = 0; j < nnz; j++) {
3896:       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3897:     }
3898:     d_nnz[i] = d;
3899:     o_nnz[i] = nnz - d;
3900:   }
3901:   PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
3902:   PetscCall(PetscFree2(d_nnz, o_nnz));

3904:   for (i = 0; i < m; i++) {
3905:     ii = i + rstart;
3906:     PetscCall(MatSetValues_MPIAIJ(B, 1, &ii, Ii[i + 1] - Ii[i], PetscSafePointerPlusOffset(J, Ii[i] - irstart), PetscSafePointerPlusOffset(v, Ii[i] - irstart), INSERT_VALUES));
3907:   }
3908:   nooffprocentries    = B->nooffprocentries;
3909:   B->nooffprocentries = PETSC_TRUE;
3910:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
3911:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
3912:   B->nooffprocentries = nooffprocentries;

3914:   /* count number of entries below block diagonal */
3915:   PetscCall(PetscFree(Aij->ld));
3916:   PetscCall(PetscCalloc1(m, &ld));
3917:   Aij->ld = ld;
3918:   for (i = 0; i < m; i++) {
3919:     nnz = Ii[i + 1] - Ii[i];
3920:     j   = 0;
3921:     while (j < nnz && J[j] < cstart) j++;
3922:     ld[i] = j;
3923:     if (J) J += nnz;
3924:   }

3926:   PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3927:   PetscFunctionReturn(PETSC_SUCCESS);
3928: }

3930: /*@
3931:   MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in `MATAIJ` format
3932:   (the default parallel PETSc format).

3934:   Collective

3936:   Input Parameters:
3937: + B - the matrix
3938: . i - the indices into `j` for the start of each local row (indices start with zero)
3939: . j - the column indices for each local row (indices start with zero)
3940: - v - optional values in the matrix

3942:   Level: developer

3944:   Notes:
3945:   The `i`, `j`, and `v` arrays ARE copied by this routine into the internal format used by PETSc;
3946:   thus you CANNOT change the matrix entries by changing the values of `v` after you have
3947:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

3949:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

3951:   A convenience routine for this functionality is `MatCreateMPIAIJWithArrays()`.

3953:   You can update the matrix with new numerical values using `MatUpdateMPIAIJWithArrays()` after this call if the column indices in `j` are sorted.

3955:   If you do **not** use `MatUpdateMPIAIJWithArrays()`, the column indices in `j` do not need to be sorted. If you will use
3956:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

3958:   The format which is used for the sparse matrix input, is equivalent to a
3959:   row-major ordering.. i.e for the following matrix, the input data expected is
3960:   as shown
3961: .vb
3962:         1 0 0
3963:         2 0 3     P0
3964:        -------
3965:         4 5 6     P1

3967:      Process0 [P0] rows_owned=[0,1]
3968:         i =  {0,1,3}  [size = nrow+1  = 2+1]
3969:         j =  {0,0,2}  [size = 3]
3970:         v =  {1,2,3}  [size = 3]

3972:      Process1 [P1] rows_owned=[2]
3973:         i =  {0,3}    [size = nrow+1  = 1+1]
3974:         j =  {0,1,2}  [size = 3]
3975:         v =  {4,5,6}  [size = 3]
3976: .ve

3978: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatCreateAIJ()`,
3979:           `MatCreateSeqAIJWithArrays()`, `MatCreateMPIAIJWithSplitArrays()`, `MatCreateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
3980: @*/
3981: PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
3982: {
3983:   PetscFunctionBegin;
3984:   PetscTryMethod(B, "MatMPIAIJSetPreallocationCSR_C", (Mat, const PetscInt[], const PetscInt[], const PetscScalar[]), (B, i, j, v));
3985:   PetscFunctionReturn(PETSC_SUCCESS);
3986: }

3988: /*@
3989:   MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in `MATMPIAIJ` format
3990:   (the default parallel PETSc format).  For good matrix assembly performance
3991:   the user should preallocate the matrix storage by setting the parameters
3992:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

3994:   Collective

3996:   Input Parameters:
3997: + B     - the matrix
3998: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3999:            (same value is used for all local rows)
4000: . d_nnz - array containing the number of nonzeros in the various rows of the
4001:            DIAGONAL portion of the local submatrix (possibly different for each row)
4002:            or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `d_nz` is used to specify the nonzero structure.
4003:            The size of this array is equal to the number of local rows, i.e 'm'.
4004:            For matrices that will be factored, you must leave room for (and set)
4005:            the diagonal entry even if it is zero.
4006: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4007:            submatrix (same value is used for all local rows).
4008: - o_nnz - array containing the number of nonzeros in the various rows of the
4009:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4010:            each row) or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `o_nz` is used to specify the nonzero
4011:            structure. The size of this array is equal to the number
4012:            of local rows, i.e 'm'.

4014:   Example Usage:
4015:   Consider the following 8x8 matrix with 34 non-zero values, that is
4016:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4017:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4018:   as follows

4020: .vb
4021:             1  2  0  |  0  3  0  |  0  4
4022:     Proc0   0  5  6  |  7  0  0  |  8  0
4023:             9  0 10  | 11  0  0  | 12  0
4024:     -------------------------------------
4025:            13  0 14  | 15 16 17  |  0  0
4026:     Proc1   0 18  0  | 19 20 21  |  0  0
4027:             0  0  0  | 22 23  0  | 24  0
4028:     -------------------------------------
4029:     Proc2  25 26 27  |  0  0 28  | 29  0
4030:            30  0  0  | 31 32 33  |  0 34
4031: .ve

4033:   This can be represented as a collection of submatrices as
4034: .vb
4035:       A B C
4036:       D E F
4037:       G H I
4038: .ve

4040:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4041:   owned by proc1, G,H,I are owned by proc2.

4043:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4044:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4045:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4047:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4048:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4049:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4050:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4051:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4052:   matrix, and [DF] as another `MATSEQAIJ` matrix.

4054:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4055:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4056:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4057:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4058:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4059:   In this case, the values of `d_nz`, `o_nz` are
4060: .vb
4061:      proc0  dnz = 2, o_nz = 2
4062:      proc1  dnz = 3, o_nz = 2
4063:      proc2  dnz = 1, o_nz = 4
4064: .ve
4065:   We are allocating `m`*(`d_nz`+`o_nz`) storage locations for every proc. This
4066:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4067:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4068:   34 values.

4070:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4071:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4072:   In the above case the values for `d_nnz`, `o_nnz` are
4073: .vb
4074:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4075:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4076:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4077: .ve
4078:   Here the space allocated is sum of all the above values i.e 34, and
4079:   hence pre-allocation is perfect.

4081:   Level: intermediate

4083:   Notes:
4084:   If the *_nnz parameter is given then the *_nz parameter is ignored

4086:   The `MATAIJ` format, also called compressed row storage (CSR), is compatible with standard Fortran
4087:   storage.  The stored row and column indices begin with zero.
4088:   See [Sparse Matrices](sec_matsparse) for details.

4090:   The parallel matrix is partitioned such that the first m0 rows belong to
4091:   process 0, the next m1 rows belong to process 1, the next m2 rows belong
4092:   to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.

4094:   The DIAGONAL portion of the local submatrix of a processor can be defined
4095:   as the submatrix which is obtained by extraction the part corresponding to
4096:   the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4097:   first row that belongs to the processor, r2 is the last row belonging to
4098:   the this processor, and c1-c2 is range of indices of the local part of a
4099:   vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4100:   common case of a square matrix, the row and column ranges are the same and
4101:   the DIAGONAL part is also square. The remaining portion of the local
4102:   submatrix (mxN) constitute the OFF-DIAGONAL portion.

4104:   If `o_nnz` and `d_nnz` are specified, then `o_nz` and `d_nz` are ignored.

4106:   You can call `MatGetInfo()` to get information on how effective the preallocation was;
4107:   for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4108:   You can also run with the option `-info` and look for messages with the string
4109:   malloc in them to see if additional memory allocation was needed.

4111: .seealso: [](ch_matrices), `Mat`, [Sparse Matrices](sec_matsparse), `MATMPIAIJ`, `MATAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatCreateAIJ()`, `MatMPIAIJSetPreallocationCSR()`,
4112:           `MatGetInfo()`, `PetscSplitOwnership()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4113: @*/
4114: PetscErrorCode MatMPIAIJSetPreallocation(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
4115: {
4116:   PetscFunctionBegin;
4119:   PetscTryMethod(B, "MatMPIAIJSetPreallocation_C", (Mat, PetscInt, const PetscInt[], PetscInt, const PetscInt[]), (B, d_nz, d_nnz, o_nz, o_nnz));
4120:   PetscFunctionReturn(PETSC_SUCCESS);
4121: }

4123: /*@
4124:   MatCreateMPIAIJWithArrays - creates a `MATMPIAIJ` matrix using arrays that contain in standard
4125:   CSR format for the local rows.

4127:   Collective

4129:   Input Parameters:
4130: + comm - MPI communicator
4131: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
4132: . n    - This value should be the same as the local size used in creating the
4133:          x vector for the matrix-vector product $ y = Ax$. (or `PETSC_DECIDE` to have
4134:          calculated if `N` is given) For square matrices n is almost always `m`.
4135: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
4136: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
4137: . 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
4138: . j    - global column indices
4139: - a    - optional matrix values

4141:   Output Parameter:
4142: . mat - the matrix

4144:   Level: intermediate

4146:   Notes:
4147:   The `i`, `j`, and `a` arrays ARE copied by this routine into the internal format used by PETSc;
4148:   thus you CANNOT change the matrix entries by changing the values of `a[]` after you have
4149:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

4151:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4153:   Once you have created the matrix you can update it with new numerical values using `MatUpdateMPIAIJWithArray()`

4155:   If you do **not** use `MatUpdateMPIAIJWithArray()`, the column indices in `j` do not need to be sorted. If you will use
4156:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

4158:   The format which is used for the sparse matrix input, is equivalent to a
4159:   row-major ordering, i.e., for the following matrix, the input data expected is
4160:   as shown
4161: .vb
4162:         1 0 0
4163:         2 0 3     P0
4164:        -------
4165:         4 5 6     P1

4167:      Process0 [P0] rows_owned=[0,1]
4168:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4169:         j =  {0,0,2}  [size = 3]
4170:         v =  {1,2,3}  [size = 3]

4172:      Process1 [P1] rows_owned=[2]
4173:         i =  {0,3}    [size = nrow+1  = 1+1]
4174:         j =  {0,1,2}  [size = 3]
4175:         v =  {4,5,6}  [size = 3]
4176: .ve

4178: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4179:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4180: @*/
4181: PetscErrorCode MatCreateMPIAIJWithArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt i[], const PetscInt j[], const PetscScalar a[], Mat *mat)
4182: {
4183:   PetscFunctionBegin;
4184:   PetscCheck(!i || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4185:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4186:   PetscCall(MatCreate(comm, mat));
4187:   PetscCall(MatSetSizes(*mat, m, n, M, N));
4188:   /* PetscCall(MatSetBlockSizes(M,bs,cbs)); */
4189:   PetscCall(MatSetType(*mat, MATMPIAIJ));
4190:   PetscCall(MatMPIAIJSetPreallocationCSR(*mat, i, j, a));
4191:   PetscFunctionReturn(PETSC_SUCCESS);
4192: }

4194: /*@
4195:   MatUpdateMPIAIJWithArrays - updates a `MATMPIAIJ` matrix using arrays that contain in standard
4196:   CSR format for the local rows. Only the numerical values are updated the other arrays must be identical to what was passed
4197:   from `MatCreateMPIAIJWithArrays()`

4199:   Deprecated: Use `MatUpdateMPIAIJWithArray()`

4201:   Collective

4203:   Input Parameters:
4204: + mat - the matrix
4205: . m   - number of local rows (Cannot be `PETSC_DECIDE`)
4206: . n   - This value should be the same as the local size used in creating the
4207:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4208:        calculated if N is given) For square matrices n is almost always m.
4209: . M   - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4210: . N   - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4211: . Ii  - row indices; that is Ii[0] = 0, Ii[row] = Ii[row-1] + number of elements in that row of the matrix
4212: . J   - column indices
4213: - v   - matrix values

4215:   Level: deprecated

4217: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4218:           `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4219: @*/
4220: PetscErrorCode MatUpdateMPIAIJWithArrays(Mat mat, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
4221: {
4222:   PetscInt        nnz, i;
4223:   PetscBool       nooffprocentries;
4224:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4225:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4226:   PetscScalar    *ad, *ao;
4227:   PetscInt        ldi, Iii, md;
4228:   const PetscInt *Adi = Ad->i;
4229:   PetscInt       *ld  = Aij->ld;

4231:   PetscFunctionBegin;
4232:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4233:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4234:   PetscCheck(m == mat->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of rows cannot change from call to MatUpdateMPIAIJWithArrays()");
4235:   PetscCheck(n == mat->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of columns cannot change from call to MatUpdateMPIAIJWithArrays()");

4237:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4238:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));

4240:   for (i = 0; i < m; i++) {
4241:     if (PetscDefined(USE_DEBUG)) {
4242:       for (PetscInt j = Ii[i] + 1; j < Ii[i + 1]; ++j) {
4243:         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);
4244:         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);
4245:       }
4246:     }
4247:     nnz = Ii[i + 1] - Ii[i];
4248:     Iii = Ii[i];
4249:     ldi = ld[i];
4250:     md  = Adi[i + 1] - Adi[i];
4251:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4252:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4253:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4254:     ad += md;
4255:     ao += nnz - md;
4256:   }
4257:   nooffprocentries      = mat->nooffprocentries;
4258:   mat->nooffprocentries = PETSC_TRUE;
4259:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4260:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4261:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4262:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4263:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4264:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4265:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4266:   mat->nooffprocentries = nooffprocentries;
4267:   PetscFunctionReturn(PETSC_SUCCESS);
4268: }

4270: /*@
4271:   MatUpdateMPIAIJWithArray - updates an `MATMPIAIJ` matrix using an array that contains the nonzero values

4273:   Collective

4275:   Input Parameters:
4276: + mat - the matrix
4277: - v   - matrix values, stored by row

4279:   Level: intermediate

4281:   Notes:
4282:   The matrix must have been obtained with `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()`

4284:   The column indices in the call to `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()` must have been sorted for this call to work correctly

4286: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4287:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4288: @*/
4289: PetscErrorCode MatUpdateMPIAIJWithArray(Mat mat, const PetscScalar v[])
4290: {
4291:   PetscInt        nnz, i, m;
4292:   PetscBool       nooffprocentries;
4293:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4294:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4295:   Mat_SeqAIJ     *Ao  = (Mat_SeqAIJ *)Aij->B->data;
4296:   PetscScalar    *ad, *ao;
4297:   const PetscInt *Adi = Ad->i, *Adj = Ao->i;
4298:   PetscInt        ldi, Iii, md;
4299:   PetscInt       *ld = Aij->ld;

4301:   PetscFunctionBegin;
4302:   m = mat->rmap->n;

4304:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4305:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));
4306:   Iii = 0;
4307:   for (i = 0; i < m; i++) {
4308:     nnz = Adi[i + 1] - Adi[i] + Adj[i + 1] - Adj[i];
4309:     ldi = ld[i];
4310:     md  = Adi[i + 1] - Adi[i];
4311:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4312:     ad += md;
4313:     if (ao) {
4314:       PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4315:       PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4316:       ao += nnz - md;
4317:     }
4318:     Iii += nnz;
4319:   }
4320:   nooffprocentries      = mat->nooffprocentries;
4321:   mat->nooffprocentries = PETSC_TRUE;
4322:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4323:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4324:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4325:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4326:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4327:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4328:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4329:   mat->nooffprocentries = nooffprocentries;
4330:   PetscFunctionReturn(PETSC_SUCCESS);
4331: }

4333: /*@
4334:   MatCreateAIJ - Creates a sparse parallel matrix in `MATAIJ` format
4335:   (the default parallel PETSc format).  For good matrix assembly performance
4336:   the user should preallocate the matrix storage by setting the parameters
4337:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4339:   Collective

4341:   Input Parameters:
4342: + comm  - MPI communicator
4343: . m     - number of local rows (or `PETSC_DECIDE` to have calculated if M is given)
4344:           This value should be the same as the local size used in creating the
4345:           y vector for the matrix-vector product y = Ax.
4346: . n     - This value should be the same as the local size used in creating the
4347:           x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4348:           calculated if N is given) For square matrices n is almost always m.
4349: . M     - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4350: . N     - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4351: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4352:           (same value is used for all local rows)
4353: . d_nnz - array containing the number of nonzeros in the various rows of the
4354:           DIAGONAL portion of the local submatrix (possibly different for each row)
4355:           or `NULL`, if `d_nz` is used to specify the nonzero structure.
4356:           The size of this array is equal to the number of local rows, i.e 'm'.
4357: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4358:           submatrix (same value is used for all local rows).
4359: - o_nnz - array containing the number of nonzeros in the various rows of the
4360:           OFF-DIAGONAL portion of the local submatrix (possibly different for
4361:           each row) or `NULL`, if `o_nz` is used to specify the nonzero
4362:           structure. The size of this array is equal to the number
4363:           of local rows, i.e 'm'.

4365:   Output Parameter:
4366: . A - the matrix

4368:   Options Database Keys:
4369: + -mat_no_inode                   - Do not use inodes
4370: . -mat_inode_limit limit          - Sets inode limit (max limit=5)
4371: - -matmult_vecscatter_view viewer - View the vecscatter (i.e., communication pattern) used in `MatMult()` of sparse parallel matrices.
4372:                                     See viewer types in manual of `MatView()`. Of them, ascii_matlab, draw or binary cause the `VecScatter`
4373:                                     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.

4375:   Level: intermediate

4377:   Notes:
4378:   It is recommended that one use `MatCreateFromOptions()` or the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
4379:   MatXXXXSetPreallocation() paradigm instead of this routine directly.
4380:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

4382:   If the *_nnz parameter is given then the *_nz parameter is ignored

4384:   The `m`,`n`,`M`,`N` parameters specify the size of the matrix, and its partitioning across
4385:   processors, while `d_nz`,`d_nnz`,`o_nz`,`o_nnz` parameters specify the approximate
4386:   storage requirements for this matrix.

4388:   If `PETSC_DECIDE` or  `PETSC_DETERMINE` is used for a particular argument on one
4389:   processor than it must be used on all processors that share the object for
4390:   that argument.

4392:   If `m` and `n` are not `PETSC_DECIDE`, then the values determine the `PetscLayout` of the matrix and the ranges returned by
4393:   `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`, and `MatGetOwnershipRangesColumn()`.

4395:   The user MUST specify either the local or global matrix dimensions
4396:   (possibly both).

4398:   The parallel matrix is partitioned across processors such that the
4399:   first `m0` rows belong to process 0, the next `m1` rows belong to
4400:   process 1, the next `m2` rows belong to process 2, etc., where
4401:   `m0`, `m1`, `m2`... are the input parameter `m` on each MPI process. I.e., each MPI process stores
4402:   values corresponding to [m x N] submatrix.

4404:   The columns are logically partitioned with the n0 columns belonging
4405:   to 0th partition, the next n1 columns belonging to the next
4406:   partition etc.. where n0,n1,n2... are the input parameter 'n'.

4408:   The DIAGONAL portion of the local submatrix on any given processor
4409:   is the submatrix corresponding to the rows and columns m,n
4410:   corresponding to the given processor. i.e diagonal matrix on
4411:   process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4412:   etc. The remaining portion of the local submatrix [m x (N-n)]
4413:   constitute the OFF-DIAGONAL portion. The example below better
4414:   illustrates this concept. The two matrices, the DIAGONAL portion and
4415:   the OFF-DIAGONAL portion are each stored as `MATSEQAIJ` matrices.

4417:   For a square global matrix we define each processor's diagonal portion
4418:   to be its local rows and the corresponding columns (a square submatrix);
4419:   each processor's off-diagonal portion encompasses the remainder of the
4420:   local matrix (a rectangular submatrix).

4422:   If `o_nnz`, `d_nnz` are specified, then `o_nz`, and `d_nz` are ignored.

4424:   When calling this routine with a single process communicator, a matrix of
4425:   type `MATSEQAIJ` is returned.  If a matrix of type `MATMPIAIJ` is desired for this
4426:   type of communicator, use the construction mechanism
4427: .vb
4428:   MatCreate(..., &A);
4429:   MatSetType(A, MATMPIAIJ);
4430:   MatSetSizes(A, m, n, M, N);
4431:   MatMPIAIJSetPreallocation(A, ...);
4432: .ve

4434:   By default, this format uses inodes (identical nodes) when possible.
4435:   We search for consecutive rows with the same nonzero structure, thereby
4436:   reusing matrix information to achieve increased efficiency.

4438:   Example Usage:
4439:   Consider the following 8x8 matrix with 34 non-zero values, that is
4440:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4441:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4442:   as follows

4444: .vb
4445:             1  2  0  |  0  3  0  |  0  4
4446:     Proc0   0  5  6  |  7  0  0  |  8  0
4447:             9  0 10  | 11  0  0  | 12  0
4448:     -------------------------------------
4449:            13  0 14  | 15 16 17  |  0  0
4450:     Proc1   0 18  0  | 19 20 21  |  0  0
4451:             0  0  0  | 22 23  0  | 24  0
4452:     -------------------------------------
4453:     Proc2  25 26 27  |  0  0 28  | 29  0
4454:            30  0  0  | 31 32 33  |  0 34
4455: .ve

4457:   This can be represented as a collection of submatrices as

4459: .vb
4460:       A B C
4461:       D E F
4462:       G H I
4463: .ve

4465:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4466:   owned by proc1, G,H,I are owned by proc2.

4468:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4469:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4470:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4472:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4473:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4474:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4475:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4476:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4477:   matrix, and [DF] as another SeqAIJ matrix.

4479:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4480:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4481:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4482:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4483:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4484:   In this case, the values of `d_nz`,`o_nz` are
4485: .vb
4486:      proc0  dnz = 2, o_nz = 2
4487:      proc1  dnz = 3, o_nz = 2
4488:      proc2  dnz = 1, o_nz = 4
4489: .ve
4490:   We are allocating m*(`d_nz`+`o_nz`) storage locations for every proc. This
4491:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4492:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4493:   34 values.

4495:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4496:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4497:   In the above case the values for d_nnz,o_nnz are
4498: .vb
4499:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4500:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4501:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4502: .ve
4503:   Here the space allocated is sum of all the above values i.e 34, and
4504:   hence pre-allocation is perfect.

4506: .seealso: [](ch_matrices), `Mat`, [Sparse Matrix Creation](sec_matsparse), `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4507:           `MATMPIAIJ`, `MatCreateMPIAIJWithArrays()`, `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`,
4508:           `MatGetOwnershipRangesColumn()`, `PetscLayout`
4509: @*/
4510: 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)
4511: {
4512:   PetscMPIInt size;

4514:   PetscFunctionBegin;
4515:   PetscCall(MatCreate(comm, A));
4516:   PetscCall(MatSetSizes(*A, m, n, M, N));
4517:   PetscCallMPI(MPI_Comm_size(comm, &size));
4518:   if (size > 1) {
4519:     PetscCall(MatSetType(*A, MATMPIAIJ));
4520:     PetscCall(MatMPIAIJSetPreallocation(*A, d_nz, d_nnz, o_nz, o_nnz));
4521:   } else {
4522:     PetscCall(MatSetType(*A, MATSEQAIJ));
4523:     PetscCall(MatSeqAIJSetPreallocation(*A, d_nz, d_nnz));
4524:   }
4525:   PetscFunctionReturn(PETSC_SUCCESS);
4526: }

4528: /*@
4529:   MatMPIAIJGetSeqAIJ - Returns the local pieces of this distributed matrix

4531:   Not Collective

4533:   Input Parameter:
4534: . A - The `MATMPIAIJ` matrix

4536:   Output Parameters:
4537: + Ad     - The local diagonal block as a `MATSEQAIJ` matrix
4538: . Ao     - The local off-diagonal block as a `MATSEQAIJ` matrix
4539: - colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix

4541:   Level: intermediate

4543:   Note:
4544:   The rows in `Ad` and `Ao` are in [0, Nr), where Nr is the number of local rows on this process. The columns
4545:   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
4546:   the number of nonzero columns in the local off-diagonal piece of the matrix `A`. The array colmap maps these
4547:   local column numbers to global column numbers in the original matrix.

4549: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`, `MatCreateAIJ()`, `MATSEQAIJ`
4550: @*/
4551: PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A, Mat *Ad, Mat *Ao, const PetscInt *colmap[])
4552: {
4553:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
4554:   PetscBool   flg;

4556:   PetscFunctionBegin;
4557:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &flg));
4558:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "This function requires a MATMPIAIJ matrix as input");
4559:   if (Ad) *Ad = a->A;
4560:   if (Ao) *Ao = a->B;
4561:   if (colmap) *colmap = a->garray;
4562:   PetscFunctionReturn(PETSC_SUCCESS);
4563: }

4565: static PetscErrorCode MatGetMultPetscSF_MPIAIJ(Mat A, PetscSF *sf)
4566: {
4567:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

4569:   PetscFunctionBegin;
4570:   *sf = a->Mvctx;
4571:   PetscFunctionReturn(PETSC_SUCCESS);
4572: }

4574: PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm, Mat inmat, PetscInt n, MatReuse scall, Mat *outmat)
4575: {
4576:   PetscInt     m, N, i, rstart, nnz, Ii;
4577:   PetscInt    *indx;
4578:   PetscScalar *values;
4579:   MatType      rootType;

4581:   PetscFunctionBegin;
4582:   PetscCall(MatGetSize(inmat, &m, &N));
4583:   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
4584:     PetscInt *dnz, *onz, sum, bs, cbs;

4586:     if (n == PETSC_DECIDE) PetscCall(PetscSplitOwnership(comm, &n, &N));
4587:     /* Check sum(n) = N */
4588:     PetscCallMPI(MPIU_Allreduce(&n, &sum, 1, MPIU_INT, MPI_SUM, comm));
4589:     PetscCheck(sum == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Sum of local columns %" PetscInt_FMT " != global columns %" PetscInt_FMT, sum, N);

4591:     PetscCallMPI(MPI_Scan(&m, &rstart, 1, MPIU_INT, MPI_SUM, comm));
4592:     rstart -= m;

4594:     MatPreallocateBegin(comm, m, n, dnz, onz);
4595:     for (i = 0; i < m; i++) {
4596:       PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4597:       PetscCall(MatPreallocateSet(i + rstart, nnz, indx, dnz, onz));
4598:       PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4599:     }

4601:     PetscCall(MatCreate(comm, outmat));
4602:     PetscCall(MatSetSizes(*outmat, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4603:     PetscCall(MatGetBlockSizes(inmat, &bs, &cbs));
4604:     PetscCall(MatSetBlockSizes(*outmat, bs, cbs));
4605:     PetscCall(MatGetRootType_Private(inmat, &rootType));
4606:     PetscCall(MatSetType(*outmat, rootType));
4607:     PetscCall(MatSeqAIJSetPreallocation(*outmat, 0, dnz));
4608:     PetscCall(MatMPIAIJSetPreallocation(*outmat, 0, dnz, 0, onz));
4609:     MatPreallocateEnd(dnz, onz);
4610:     PetscCall(MatSetOption(*outmat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
4611:   }

4613:   /* numeric phase */
4614:   PetscCall(MatGetOwnershipRange(*outmat, &rstart, NULL));
4615:   for (i = 0; i < m; i++) {
4616:     PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4617:     Ii = i + rstart;
4618:     PetscCall(MatSetValues(*outmat, 1, &Ii, nnz, indx, values, INSERT_VALUES));
4619:     PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4620:   }
4621:   PetscCall(MatAssemblyBegin(*outmat, MAT_FINAL_ASSEMBLY));
4622:   PetscCall(MatAssemblyEnd(*outmat, MAT_FINAL_ASSEMBLY));
4623:   PetscFunctionReturn(PETSC_SUCCESS);
4624: }

4626: static PetscErrorCode MatMergeSeqsToMPIDestroy(PetscCtxRt data)
4627: {
4628:   MatMergeSeqsToMPI *merge = *(MatMergeSeqsToMPI **)data;

4630:   PetscFunctionBegin;
4631:   if (!merge) PetscFunctionReturn(PETSC_SUCCESS);
4632:   PetscCall(PetscFree(merge->id_r));
4633:   PetscCall(PetscFree(merge->len_s));
4634:   PetscCall(PetscFree(merge->len_r));
4635:   PetscCall(PetscFree(merge->bi));
4636:   PetscCall(PetscFree(merge->bj));
4637:   PetscCall(PetscFree(merge->buf_ri[0]));
4638:   PetscCall(PetscFree(merge->buf_ri));
4639:   PetscCall(PetscFree(merge->buf_rj[0]));
4640:   PetscCall(PetscFree(merge->buf_rj));
4641:   PetscCall(PetscFree(merge->coi));
4642:   PetscCall(PetscFree(merge->coj));
4643:   PetscCall(PetscFree(merge->owners_co));
4644:   PetscCall(PetscLayoutDestroy(&merge->rowmap));
4645:   PetscCall(PetscFree(merge));
4646:   PetscFunctionReturn(PETSC_SUCCESS);
4647: }

4649: #include <../src/mat/utils/freespace.h>
4650: #include <petscbt.h>

4652: /*@
4653:   MatCreateMPIAIJSumSeqAIJNumeric - Fill the numerical values of an `MATMPIAIJ` matrix previously created by
4654:   `MatCreateMPIAIJSumSeqAIJSymbolic()` by summing the local `MATSEQAIJ` contributions from each process.

4656:   Collective

4658:   Input Parameters:
4659: + seqmat - the local `MATSEQAIJ` contribution from this process
4660: - mpimat - the target `MATMPIAIJ` matrix created by `MatCreateMPIAIJSumSeqAIJSymbolic()`

4662:   Level: developer

4664: .seealso: `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJSumSeqAIJSymbolic()`, `MatCreateMPIAIJSumSeqAIJ()`
4665: @*/
4666: PetscErrorCode MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat, Mat mpimat)
4667: {
4668:   MPI_Comm           comm;
4669:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)seqmat->data;
4670:   PetscMPIInt        size, rank, taga, *len_s;
4671:   PetscInt           N = mpimat->cmap->N, i, j, *owners, *ai = a->i, *aj, m;
4672:   PetscMPIInt        proc, k;
4673:   PetscInt         **buf_ri, **buf_rj;
4674:   PetscInt           anzi, *bj_i, *bi, *bj, arow, bnzi, nextaj;
4675:   PetscInt           nrows, **buf_ri_k, **nextrow, **nextai;
4676:   MPI_Request       *s_waits, *r_waits;
4677:   MPI_Status        *status;
4678:   const MatScalar   *aa, *a_a;
4679:   MatScalar        **abuf_r, *ba_i;
4680:   MatMergeSeqsToMPI *merge;
4681:   PetscContainer     container;

4683:   PetscFunctionBegin;
4684:   PetscCall(PetscObjectGetComm((PetscObject)mpimat, &comm));
4685:   PetscCall(PetscLogEventBegin(MAT_Seqstompinum, seqmat, 0, 0, 0));

4687:   PetscCallMPI(MPI_Comm_size(comm, &size));
4688:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4690:   PetscCall(PetscObjectQuery((PetscObject)mpimat, "MatMergeSeqsToMPI", (PetscObject *)&container));
4691:   PetscCheck(container, PetscObjectComm((PetscObject)mpimat), PETSC_ERR_PLIB, "Mat not created from MatCreateMPIAIJSumSeqAIJSymbolic");
4692:   PetscCall(PetscContainerGetPointer(container, &merge));
4693:   PetscCall(MatSeqAIJGetArrayRead(seqmat, &a_a));
4694:   aa = a_a;

4696:   bi     = merge->bi;
4697:   bj     = merge->bj;
4698:   buf_ri = merge->buf_ri;
4699:   buf_rj = merge->buf_rj;

4701:   PetscCall(PetscMalloc1(size, &status));
4702:   owners = merge->rowmap->range;
4703:   len_s  = merge->len_s;

4705:   /* send and recv matrix values */
4706:   PetscCall(PetscObjectGetNewTag((PetscObject)mpimat, &taga));
4707:   PetscCall(PetscPostIrecvScalar(comm, taga, merge->nrecv, merge->id_r, merge->len_r, &abuf_r, &r_waits));

4709:   PetscCall(PetscMalloc1(merge->nsend + 1, &s_waits));
4710:   for (proc = 0, k = 0; proc < size; proc++) {
4711:     if (!len_s[proc]) continue;
4712:     i = owners[proc];
4713:     PetscCallMPI(MPIU_Isend(aa + ai[i], len_s[proc], MPIU_MATSCALAR, proc, taga, comm, s_waits + k));
4714:     k++;
4715:   }

4717:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, r_waits, status));
4718:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, s_waits, status));
4719:   PetscCall(PetscFree(status));

4721:   PetscCall(PetscFree(s_waits));
4722:   PetscCall(PetscFree(r_waits));

4724:   /* insert mat values of mpimat */
4725:   PetscCall(PetscMalloc1(N, &ba_i));
4726:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4728:   for (k = 0; k < merge->nrecv; k++) {
4729:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4730:     nrows       = *buf_ri_k[k];
4731:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4732:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4733:   }

4735:   /* set values of ba */
4736:   m = merge->rowmap->n;
4737:   for (i = 0; i < m; i++) {
4738:     arow = owners[rank] + i;
4739:     bj_i = bj + bi[i]; /* col indices of the i-th row of mpimat */
4740:     bnzi = bi[i + 1] - bi[i];
4741:     PetscCall(PetscArrayzero(ba_i, bnzi));

4743:     /* add local non-zero vals of this proc's seqmat into ba */
4744:     anzi   = ai[arow + 1] - ai[arow];
4745:     aj     = a->j + ai[arow];
4746:     aa     = a_a + ai[arow];
4747:     nextaj = 0;
4748:     for (j = 0; nextaj < anzi; j++) {
4749:       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4750:         ba_i[j] += aa[nextaj++];
4751:       }
4752:     }

4754:     /* add received vals into ba */
4755:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4756:       /* i-th row */
4757:       if (i == *nextrow[k]) {
4758:         anzi   = *(nextai[k] + 1) - *nextai[k];
4759:         aj     = buf_rj[k] + *nextai[k];
4760:         aa     = abuf_r[k] + *nextai[k];
4761:         nextaj = 0;
4762:         for (j = 0; nextaj < anzi; j++) {
4763:           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4764:             ba_i[j] += aa[nextaj++];
4765:           }
4766:         }
4767:         nextrow[k]++;
4768:         nextai[k]++;
4769:       }
4770:     }
4771:     PetscCall(MatSetValues(mpimat, 1, &arow, bnzi, bj_i, ba_i, INSERT_VALUES));
4772:   }
4773:   PetscCall(MatSeqAIJRestoreArrayRead(seqmat, &a_a));
4774:   PetscCall(MatAssemblyBegin(mpimat, MAT_FINAL_ASSEMBLY));
4775:   PetscCall(MatAssemblyEnd(mpimat, MAT_FINAL_ASSEMBLY));

4777:   PetscCall(PetscFree(abuf_r[0]));
4778:   PetscCall(PetscFree(abuf_r));
4779:   PetscCall(PetscFree(ba_i));
4780:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));
4781:   PetscCall(PetscLogEventEnd(MAT_Seqstompinum, seqmat, 0, 0, 0));
4782:   PetscFunctionReturn(PETSC_SUCCESS);
4783: }

4785: /*@
4786:   MatCreateMPIAIJSumSeqAIJSymbolic - Create the symbolic (nonzero-pattern) portion of an `MATMPIAIJ` matrix
4787:   obtained by summing local `MATSEQAIJ` contributions from each process.

4789:   Collective

4791:   Input Parameters:
4792: + comm   - the communicator
4793: . seqmat - the local `MATSEQAIJ` contribution from this process
4794: . m      - the number of local rows for the resulting `MATMPIAIJ` matrix, or `PETSC_DECIDE`
4795: - n      - the number of local columns for the resulting `MATMPIAIJ` matrix, or `PETSC_DECIDE`

4797:   Output Parameter:
4798: . mpimat - the newly created `MATMPIAIJ` matrix

4800:   Level: developer

4802:   Note:
4803:   The numerical values are filled in by a subsequent call to `MatCreateMPIAIJSumSeqAIJNumeric()`.

4805: .seealso: `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJSumSeqAIJNumeric()`, `MatCreateMPIAIJSumSeqAIJ()`
4806: @*/
4807: PetscErrorCode MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, Mat *mpimat)
4808: {
4809:   Mat                B_mpi;
4810:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)seqmat->data;
4811:   PetscMPIInt        size, rank, tagi, tagj, *len_s, *len_si, *len_ri;
4812:   PetscInt         **buf_rj, **buf_ri, **buf_ri_k;
4813:   PetscInt           M = seqmat->rmap->n, N = seqmat->cmap->n, i, *owners, *ai = a->i, *aj = a->j;
4814:   PetscInt           len, *dnz, *onz, bs, cbs;
4815:   PetscInt           k, anzi, *bi, *bj, *lnk, nlnk, arow, bnzi;
4816:   PetscInt           nrows, *buf_s, *buf_si, *buf_si_i, **nextrow, **nextai;
4817:   MPI_Request       *si_waits, *sj_waits, *ri_waits, *rj_waits;
4818:   MPI_Status        *status;
4819:   PetscFreeSpaceList free_space = NULL, current_space = NULL;
4820:   PetscBT            lnkbt;
4821:   MatMergeSeqsToMPI *merge;
4822:   PetscContainer     container;

4824:   PetscFunctionBegin;
4825:   PetscCall(PetscLogEventBegin(MAT_Seqstompisym, seqmat, 0, 0, 0));

4827:   /* make sure it is a PETSc comm */
4828:   PetscCall(PetscCommDuplicate(comm, &comm, NULL));
4829:   PetscCallMPI(MPI_Comm_size(comm, &size));
4830:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4832:   PetscCall(PetscNew(&merge));
4833:   PetscCall(PetscMalloc1(size, &status));

4835:   /* determine row ownership */
4836:   PetscCall(PetscLayoutCreate(comm, &merge->rowmap));
4837:   PetscCall(PetscLayoutSetLocalSize(merge->rowmap, m));
4838:   PetscCall(PetscLayoutSetSize(merge->rowmap, M));
4839:   PetscCall(PetscLayoutSetBlockSize(merge->rowmap, 1));
4840:   PetscCall(PetscLayoutSetUp(merge->rowmap));
4841:   PetscCall(PetscMalloc1(size, &len_si));
4842:   PetscCall(PetscMalloc1(size, &merge->len_s));

4844:   m      = merge->rowmap->n;
4845:   owners = merge->rowmap->range;

4847:   /* determine the number of messages to send, their lengths */
4848:   len_s = merge->len_s;

4850:   len          = 0; /* length of buf_si[] */
4851:   merge->nsend = 0;
4852:   for (PetscMPIInt proc = 0; proc < size; proc++) {
4853:     len_si[proc] = 0;
4854:     if (proc == rank) {
4855:       len_s[proc] = 0;
4856:     } else {
4857:       PetscCall(PetscMPIIntCast(owners[proc + 1] - owners[proc] + 1, &len_si[proc]));
4858:       PetscCall(PetscMPIIntCast(ai[owners[proc + 1]] - ai[owners[proc]], &len_s[proc])); /* num of rows to be sent to [proc] */
4859:     }
4860:     if (len_s[proc]) {
4861:       merge->nsend++;
4862:       nrows = 0;
4863:       for (i = owners[proc]; i < owners[proc + 1]; i++) {
4864:         if (ai[i + 1] > ai[i]) nrows++;
4865:       }
4866:       PetscCall(PetscMPIIntCast(2 * (nrows + 1), &len_si[proc]));
4867:       len += len_si[proc];
4868:     }
4869:   }

4871:   /* determine the number and length of messages to receive for ij-structure */
4872:   PetscCall(PetscGatherNumberOfMessages(comm, NULL, len_s, &merge->nrecv));
4873:   PetscCall(PetscGatherMessageLengths2(comm, merge->nsend, merge->nrecv, len_s, len_si, &merge->id_r, &merge->len_r, &len_ri));

4875:   /* post the Irecv of j-structure */
4876:   PetscCall(PetscCommGetNewTag(comm, &tagj));
4877:   PetscCall(PetscPostIrecvInt(comm, tagj, merge->nrecv, merge->id_r, merge->len_r, &buf_rj, &rj_waits));

4879:   /* post the Isend of j-structure */
4880:   PetscCall(PetscMalloc2(merge->nsend, &si_waits, merge->nsend, &sj_waits));

4882:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4883:     if (!len_s[proc]) continue;
4884:     i = owners[proc];
4885:     PetscCallMPI(MPIU_Isend(aj + ai[i], len_s[proc], MPIU_INT, proc, tagj, comm, sj_waits + k));
4886:     k++;
4887:   }

4889:   /* receives and sends of j-structure are complete */
4890:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, rj_waits, status));
4891:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, sj_waits, status));

4893:   /* send and recv i-structure */
4894:   PetscCall(PetscCommGetNewTag(comm, &tagi));
4895:   PetscCall(PetscPostIrecvInt(comm, tagi, merge->nrecv, merge->id_r, len_ri, &buf_ri, &ri_waits));

4897:   PetscCall(PetscMalloc1(len + 1, &buf_s));
4898:   buf_si = buf_s; /* points to the beginning of k-th msg to be sent */
4899:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4900:     if (!len_s[proc]) continue;
4901:     /* form outgoing message for i-structure:
4902:          buf_si[0]:                 nrows to be sent
4903:                [1:nrows]:           row index (global)
4904:                [nrows+1:2*nrows+1]: i-structure index
4905:     */
4906:     nrows       = len_si[proc] / 2 - 1;
4907:     buf_si_i    = buf_si + nrows + 1;
4908:     buf_si[0]   = nrows;
4909:     buf_si_i[0] = 0;
4910:     nrows       = 0;
4911:     for (i = owners[proc]; i < owners[proc + 1]; i++) {
4912:       anzi = ai[i + 1] - ai[i];
4913:       if (anzi) {
4914:         buf_si_i[nrows + 1] = buf_si_i[nrows] + anzi; /* i-structure */
4915:         buf_si[nrows + 1]   = i - owners[proc];       /* local row index */
4916:         nrows++;
4917:       }
4918:     }
4919:     PetscCallMPI(MPIU_Isend(buf_si, len_si[proc], MPIU_INT, proc, tagi, comm, si_waits + k));
4920:     k++;
4921:     buf_si += len_si[proc];
4922:   }

4924:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, ri_waits, status));
4925:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, si_waits, status));

4927:   PetscCall(PetscInfo(seqmat, "nsend: %d, nrecv: %d\n", merge->nsend, merge->nrecv));
4928:   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]));

4930:   PetscCall(PetscFree(len_si));
4931:   PetscCall(PetscFree(len_ri));
4932:   PetscCall(PetscFree(rj_waits));
4933:   PetscCall(PetscFree2(si_waits, sj_waits));
4934:   PetscCall(PetscFree(ri_waits));
4935:   PetscCall(PetscFree(buf_s));
4936:   PetscCall(PetscFree(status));

4938:   /* compute a local seq matrix in each processor */
4939:   /* allocate bi array and free space for accumulating nonzero column info */
4940:   PetscCall(PetscMalloc1(m + 1, &bi));
4941:   bi[0] = 0;

4943:   /* create and initialize a linked list */
4944:   nlnk = N + 1;
4945:   PetscCall(PetscLLCreate(N, N, nlnk, lnk, lnkbt));

4947:   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4948:   len = ai[owners[rank + 1]] - ai[owners[rank]];
4949:   PetscCall(PetscFreeSpaceGet(PetscIntMultTruncate(2, len) + 1, &free_space));

4951:   current_space = free_space;

4953:   /* determine symbolic info for each local row */
4954:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4956:   for (k = 0; k < merge->nrecv; k++) {
4957:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4958:     nrows       = *buf_ri_k[k];
4959:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4960:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4961:   }

4963:   MatPreallocateBegin(comm, m, n, dnz, onz);
4964:   len = 0;
4965:   for (i = 0; i < m; i++) {
4966:     bnzi = 0;
4967:     /* add local non-zero cols of this proc's seqmat into lnk */
4968:     arow = owners[rank] + i;
4969:     anzi = ai[arow + 1] - ai[arow];
4970:     aj   = a->j + ai[arow];
4971:     PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4972:     bnzi += nlnk;
4973:     /* add received col data into lnk */
4974:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4975:       if (i == *nextrow[k]) {            /* i-th row */
4976:         anzi = *(nextai[k] + 1) - *nextai[k];
4977:         aj   = buf_rj[k] + *nextai[k];
4978:         PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4979:         bnzi += nlnk;
4980:         nextrow[k]++;
4981:         nextai[k]++;
4982:       }
4983:     }
4984:     if (len < bnzi) len = bnzi; /* =max(bnzi) */

4986:     /* if free space is not available, make more free space */
4987:     if (current_space->local_remaining < bnzi) PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(bnzi, current_space->total_array_size), &current_space));
4988:     /* copy data into free space, then initialize lnk */
4989:     PetscCall(PetscLLClean(N, N, bnzi, lnk, current_space->array, lnkbt));
4990:     PetscCall(MatPreallocateSet(i + owners[rank], bnzi, current_space->array, dnz, onz));

4992:     current_space->array += bnzi;
4993:     current_space->local_used += bnzi;
4994:     current_space->local_remaining -= bnzi;

4996:     bi[i + 1] = bi[i] + bnzi;
4997:   }

4999:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));

5001:   PetscCall(PetscMalloc1(bi[m], &bj));
5002:   PetscCall(PetscFreeSpaceContiguous(&free_space, bj));
5003:   PetscCall(PetscLLDestroy(lnk, lnkbt));

5005:   /* create symbolic parallel matrix B_mpi */
5006:   PetscCall(MatGetBlockSizes(seqmat, &bs, &cbs));
5007:   PetscCall(MatCreate(comm, &B_mpi));
5008:   if (n == PETSC_DECIDE) PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, N));
5009:   else PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
5010:   PetscCall(MatSetBlockSizes(B_mpi, bs, cbs));
5011:   PetscCall(MatSetType(B_mpi, MATMPIAIJ));
5012:   PetscCall(MatMPIAIJSetPreallocation(B_mpi, 0, dnz, 0, onz));
5013:   MatPreallocateEnd(dnz, onz);
5014:   PetscCall(MatSetOption(B_mpi, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));

5016:   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
5017:   B_mpi->assembled = PETSC_FALSE;
5018:   merge->bi        = bi;
5019:   merge->bj        = bj;
5020:   merge->buf_ri    = buf_ri;
5021:   merge->buf_rj    = buf_rj;
5022:   merge->coi       = NULL;
5023:   merge->coj       = NULL;
5024:   merge->owners_co = NULL;

5026:   PetscCall(PetscCommDestroy(&comm));

5028:   /* attach the supporting struct to B_mpi for reuse */
5029:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
5030:   PetscCall(PetscContainerSetPointer(container, merge));
5031:   PetscCall(PetscContainerSetCtxDestroy(container, MatMergeSeqsToMPIDestroy));
5032:   PetscCall(PetscObjectCompose((PetscObject)B_mpi, "MatMergeSeqsToMPI", (PetscObject)container));
5033:   PetscCall(PetscContainerDestroy(&container));
5034:   *mpimat = B_mpi;

5036:   PetscCall(PetscLogEventEnd(MAT_Seqstompisym, seqmat, 0, 0, 0));
5037:   PetscFunctionReturn(PETSC_SUCCESS);
5038: }

5040: /*@
5041:   MatCreateMPIAIJSumSeqAIJ - Creates a `MATMPIAIJ` matrix by adding sequential
5042:   matrices from each processor

5044:   Collective

5046:   Input Parameters:
5047: + comm   - the communicators the parallel matrix will live on
5048: . seqmat - the input sequential matrices
5049: . m      - number of local rows (or `PETSC_DECIDE`)
5050: . n      - number of local columns (or `PETSC_DECIDE`)
5051: - scall  - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5053:   Output Parameter:
5054: . mpimat - the parallel matrix generated

5056:   Level: advanced

5058:   Note:
5059:   The dimensions of the sequential matrix in each processor MUST be the same.
5060:   The input seqmat is included into the container `MatMergeSeqsToMPIDestroy`, and will be
5061:   destroyed when `mpimat` is destroyed. Call `PetscObjectQuery()` to access `seqmat`.

5063: .seealso: [](ch_matrices), `Mat`, `MatCreateAIJ()`
5064: @*/
5065: PetscErrorCode MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, MatReuse scall, Mat *mpimat)
5066: {
5067:   PetscMPIInt size;

5069:   PetscFunctionBegin;
5070:   PetscCallMPI(MPI_Comm_size(comm, &size));
5071:   if (size == 1) {
5072:     PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5073:     if (scall == MAT_INITIAL_MATRIX) PetscCall(MatDuplicate(seqmat, MAT_COPY_VALUES, mpimat));
5074:     else PetscCall(MatCopy(seqmat, *mpimat, SAME_NONZERO_PATTERN));
5075:     PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5076:     PetscFunctionReturn(PETSC_SUCCESS);
5077:   }
5078:   PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5079:   if (scall == MAT_INITIAL_MATRIX) PetscCall(MatCreateMPIAIJSumSeqAIJSymbolic(comm, seqmat, m, n, mpimat));
5080:   PetscCall(MatCreateMPIAIJSumSeqAIJNumeric(seqmat, *mpimat));
5081:   PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5082:   PetscFunctionReturn(PETSC_SUCCESS);
5083: }

5085: /*@
5086:   MatAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATAIJ` matrix.

5088:   Not Collective

5090:   Input Parameter:
5091: . A - the matrix

5093:   Output Parameter:
5094: . A_loc - the local sequential matrix generated

5096:   Level: developer

5098:   Notes:
5099:   The matrix is created by taking `A`'s local rows and putting them into a sequential matrix
5100:   with `mlocal` rows and `n` columns. Where `mlocal` is obtained with `MatGetLocalSize()` and
5101:   `n` is the global column count obtained with `MatGetSize()`

5103:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5105:   For parallel matrices this creates an entirely new matrix. If the matrix is sequential it merely increases the reference count.

5107:   Destroy the matrix with `MatDestroy()`

5109: .seealso: [](ch_matrices), `Mat`, `MatMPIAIJGetLocalMat()`
5110: @*/
5111: PetscErrorCode MatAIJGetLocalMat(Mat A, Mat *A_loc)
5112: {
5113:   PetscBool mpi;

5115:   PetscFunctionBegin;
5116:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &mpi));
5117:   if (mpi) PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, A_loc));
5118:   else {
5119:     *A_loc = A;
5120:     PetscCall(PetscObjectReference((PetscObject)*A_loc));
5121:   }
5122:   PetscFunctionReturn(PETSC_SUCCESS);
5123: }

5125: /*@
5126:   MatMPIAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix.

5128:   Not Collective

5130:   Input Parameters:
5131: + A     - the matrix
5132: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5134:   Output Parameter:
5135: . A_loc - the local sequential matrix generated

5137:   Level: developer

5139:   Notes:
5140:   The matrix is created by taking all `A`'s local rows and putting them into a sequential
5141:   matrix with `mlocal` rows and `n` columns.`mlocal` is the row count obtained with
5142:   `MatGetLocalSize()` and `n` is the global column count obtained with `MatGetSize()`.

5144:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5146:   When `A` is sequential and `MAT_INITIAL_MATRIX` is requested, the matrix returned is the diagonal part of `A` (which contains the entire matrix),
5147:   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
5148:   then `MatCopy`(Adiag,*`A_loc`,`SAME_NONZERO_PATTERN`) is called to fill `A_loc`. Thus one can preallocate the appropriate sequential matrix `A_loc`
5149:   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.

5151: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMatCondensed()`, `MatMPIAIJGetLocalMatMerge()`
5152: @*/
5153: PetscErrorCode MatMPIAIJGetLocalMat(Mat A, MatReuse scall, Mat *A_loc)
5154: {
5155:   Mat_MPIAIJ        *mpimat = (Mat_MPIAIJ *)A->data;
5156:   Mat_SeqAIJ        *mat, *a, *b;
5157:   PetscInt          *ai, *aj, *bi, *bj, *cmap = mpimat->garray;
5158:   const PetscScalar *aa, *ba, *aav, *bav;
5159:   PetscScalar       *ca, *cam;
5160:   PetscMPIInt        size;
5161:   PetscInt           am = A->rmap->n, i, j, k, cstart = A->cmap->rstart;
5162:   PetscInt          *ci, *cj, col, ncols_d, ncols_o, jo;
5163:   PetscBool          match;

5165:   PetscFunctionBegin;
5166:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &match));
5167:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5168:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5169:   if (size == 1) {
5170:     if (scall == MAT_INITIAL_MATRIX) {
5171:       PetscCall(PetscObjectReference((PetscObject)mpimat->A));
5172:       *A_loc = mpimat->A;
5173:     } else if (scall == MAT_REUSE_MATRIX) {
5174:       PetscCall(MatCopy(mpimat->A, *A_loc, SAME_NONZERO_PATTERN));
5175:     }
5176:     PetscFunctionReturn(PETSC_SUCCESS);
5177:   }

5179:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5180:   a  = (Mat_SeqAIJ *)mpimat->A->data;
5181:   b  = (Mat_SeqAIJ *)mpimat->B->data;
5182:   ai = a->i;
5183:   aj = a->j;
5184:   bi = b->i;
5185:   bj = b->j;
5186:   PetscCall(MatSeqAIJGetArrayRead(mpimat->A, &aav));
5187:   PetscCall(MatSeqAIJGetArrayRead(mpimat->B, &bav));
5188:   aa = aav;
5189:   ba = bav;
5190:   if (scall == MAT_INITIAL_MATRIX) {
5191:     PetscCall(PetscMalloc1(1 + am, &ci));
5192:     ci[0] = 0;
5193:     for (i = 0; i < am; i++) ci[i + 1] = ci[i] + (ai[i + 1] - ai[i]) + (bi[i + 1] - bi[i]);
5194:     PetscCall(PetscMalloc1(1 + ci[am], &cj));
5195:     PetscCall(PetscMalloc1(1 + ci[am], &ca));
5196:     k = 0;
5197:     for (i = 0; i < am; i++) {
5198:       ncols_o = bi[i + 1] - bi[i];
5199:       ncols_d = ai[i + 1] - ai[i];
5200:       /* off-diagonal portion of A */
5201:       for (jo = 0; jo < ncols_o; jo++, bj++) {
5202:         col = cmap[*bj];
5203:         if (col >= cstart) break;
5204:         cj[k]   = col;
5205:         ca[k++] = *ba++;
5206:       }
5207:       /* diagonal portion of A */
5208:       for (j = 0; j < ncols_d; j++) {
5209:         cj[k]   = cstart + *aj++;
5210:         ca[k++] = *aa++;
5211:       }
5212:       /* off-diagonal portion of A */
5213:       for (j = jo; j < ncols_o; j++) {
5214:         cj[k]   = cmap[*bj++];
5215:         ca[k++] = *ba++;
5216:       }
5217:     }
5218:     /* put together the new matrix */
5219:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, A->cmap->N, ci, cj, ca, A_loc));
5220:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5221:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5222:     mat          = (Mat_SeqAIJ *)(*A_loc)->data;
5223:     mat->free_a  = PETSC_TRUE;
5224:     mat->free_ij = PETSC_TRUE;
5225:     mat->nonew   = 0;
5226:   } else if (scall == MAT_REUSE_MATRIX) {
5227:     mat = (Mat_SeqAIJ *)(*A_loc)->data;
5228:     ci  = mat->i;
5229:     cj  = mat->j;
5230:     PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &cam));
5231:     for (i = 0; i < am; i++) {
5232:       /* off-diagonal portion of A */
5233:       ncols_o = bi[i + 1] - bi[i];
5234:       for (jo = 0; jo < ncols_o; jo++, bj++) {
5235:         col = cmap[*bj];
5236:         if (col >= cstart) break;
5237:         *cam++ = *ba++;
5238:       }
5239:       /* diagonal portion of A */
5240:       ncols_d = ai[i + 1] - ai[i];
5241:       for (j = 0; j < ncols_d; j++) *cam++ = *aa++;
5242:       /* off-diagonal portion of A */
5243:       for (j = jo; j < ncols_o; j++, bj++) *cam++ = *ba++;
5244:     }
5245:     PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &cam));
5246:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5247:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->A, &aav));
5248:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->B, &bav));
5249:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5250:   PetscFunctionReturn(PETSC_SUCCESS);
5251: }

5253: /*@
5254:   MatMPIAIJGetLocalMatMerge - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix by taking all its local rows and putting them into a sequential matrix with
5255:   mlocal rows and n columns. Where n is the sum of the number of columns of the diagonal and off-diagonal part

5257:   Not Collective

5259:   Input Parameters:
5260: + A     - the matrix
5261: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5263:   Output Parameters:
5264: + glob  - sequential `IS` with global indices associated with the columns of the local sequential matrix generated (can be `NULL`)
5265: - A_loc - the local sequential matrix generated

5267:   Level: developer

5269:   Note:
5270:   This is different from `MatMPIAIJGetLocalMat()` since the first columns in the returning matrix are those associated with the diagonal
5271:   part, then those associated with the off-diagonal part (in its local ordering)

5273: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`
5274: @*/
5275: PetscErrorCode MatMPIAIJGetLocalMatMerge(Mat A, MatReuse scall, IS *glob, Mat *A_loc)
5276: {
5277:   Mat             Ao, Ad;
5278:   const PetscInt *cmap;
5279:   PetscMPIInt     size;
5280:   PetscErrorCode (*f)(Mat, MatReuse, IS *, Mat *);

5282:   PetscFunctionBegin;
5283:   PetscCall(MatMPIAIJGetSeqAIJ(A, &Ad, &Ao, &cmap));
5284:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5285:   if (size == 1) {
5286:     if (scall == MAT_INITIAL_MATRIX) {
5287:       PetscCall(PetscObjectReference((PetscObject)Ad));
5288:       *A_loc = Ad;
5289:     } else if (scall == MAT_REUSE_MATRIX) {
5290:       PetscCall(MatCopy(Ad, *A_loc, SAME_NONZERO_PATTERN));
5291:     }
5292:     if (glob) PetscCall(ISCreateStride(PetscObjectComm((PetscObject)Ad), Ad->cmap->n, Ad->cmap->rstart, 1, glob));
5293:     PetscFunctionReturn(PETSC_SUCCESS);
5294:   }
5295:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatMPIAIJGetLocalMatMerge_C", &f));
5296:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5297:   if (f) PetscCall((*f)(A, scall, glob, A_loc));
5298:   else {
5299:     Mat_SeqAIJ        *a = (Mat_SeqAIJ *)Ad->data;
5300:     Mat_SeqAIJ        *b = (Mat_SeqAIJ *)Ao->data;
5301:     Mat_SeqAIJ        *c;
5302:     PetscInt          *ai = a->i, *aj = a->j;
5303:     PetscInt          *bi = b->i, *bj = b->j;
5304:     PetscInt          *ci, *cj;
5305:     const PetscScalar *aa, *ba;
5306:     PetscScalar       *ca;
5307:     PetscInt           i, j, am, dn, on;

5309:     PetscCall(MatGetLocalSize(Ad, &am, &dn));
5310:     PetscCall(MatGetLocalSize(Ao, NULL, &on));
5311:     PetscCall(MatSeqAIJGetArrayRead(Ad, &aa));
5312:     PetscCall(MatSeqAIJGetArrayRead(Ao, &ba));
5313:     if (scall == MAT_INITIAL_MATRIX) {
5314:       PetscInt k;
5315:       PetscCall(PetscMalloc1(1 + am, &ci));
5316:       PetscCall(PetscMalloc1(ai[am] + bi[am], &cj));
5317:       PetscCall(PetscMalloc1(ai[am] + bi[am], &ca));
5318:       ci[0] = 0;
5319:       for (i = 0, k = 0; i < am; i++) {
5320:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5321:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5322:         ci[i + 1]              = ci[i] + ncols_o + ncols_d;
5323:         /* diagonal portion of A */
5324:         for (j = 0; j < ncols_d; j++, k++) {
5325:           cj[k] = *aj++;
5326:           ca[k] = *aa++;
5327:         }
5328:         /* off-diagonal portion of A */
5329:         for (j = 0; j < ncols_o; j++, k++) {
5330:           cj[k] = dn + *bj++;
5331:           ca[k] = *ba++;
5332:         }
5333:       }
5334:       /* put together the new matrix */
5335:       PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, dn + on, ci, cj, ca, A_loc));
5336:       /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5337:       /* Since these are PETSc arrays, change flags to free them as necessary. */
5338:       c          = (Mat_SeqAIJ *)(*A_loc)->data;
5339:       c->free_a  = PETSC_TRUE;
5340:       c->free_ij = PETSC_TRUE;
5341:       c->nonew   = 0;
5342:       PetscCall(MatSetType(*A_loc, ((PetscObject)Ad)->type_name));
5343:     } else if (scall == MAT_REUSE_MATRIX) {
5344:       PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &ca));
5345:       for (i = 0; i < am; i++) {
5346:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5347:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5348:         /* diagonal portion of A */
5349:         for (j = 0; j < ncols_d; j++) *ca++ = *aa++;
5350:         /* off-diagonal portion of A */
5351:         for (j = 0; j < ncols_o; j++) *ca++ = *ba++;
5352:       }
5353:       PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &ca));
5354:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5355:     PetscCall(MatSeqAIJRestoreArrayRead(Ad, &aa));
5356:     PetscCall(MatSeqAIJRestoreArrayRead(Ao, &aa));
5357:     if (glob) {
5358:       PetscInt cst, *gidx;

5360:       PetscCall(MatGetOwnershipRangeColumn(A, &cst, NULL));
5361:       PetscCall(PetscMalloc1(dn + on, &gidx));
5362:       for (i = 0; i < dn; i++) gidx[i] = cst + i;
5363:       for (i = 0; i < on; i++) gidx[i + dn] = cmap[i];
5364:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)Ad), dn + on, gidx, PETSC_OWN_POINTER, glob));
5365:     }
5366:   }
5367:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5368:   PetscFunctionReturn(PETSC_SUCCESS);
5369: }

5371: /*@
5372:   MatMPIAIJGetLocalMatCondensed - Creates a `MATSEQAIJ` matrix from an `MATMPIAIJ` matrix by taking all its local rows and NON-ZERO columns

5374:   Not Collective

5376:   Input Parameters:
5377: + A     - the matrix
5378: . scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`
5379: . row   - index set of rows to extract (or `NULL`)
5380: - col   - index set of columns to extract (or `NULL`)

5382:   Output Parameter:
5383: . A_loc - the local sequential matrix generated

5385:   Level: developer

5387: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`
5388: @*/
5389: PetscErrorCode MatMPIAIJGetLocalMatCondensed(Mat A, MatReuse scall, IS *row, IS *col, Mat *A_loc)
5390: {
5391:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5392:   PetscInt    i, start, end, ncols, nzA, nzB, *cmap, imark, *idx;
5393:   IS          isrowa, iscola;
5394:   Mat        *aloc;
5395:   PetscBool   match;

5397:   PetscFunctionBegin;
5398:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &match));
5399:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5400:   PetscCall(PetscLogEventBegin(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5401:   if (!row) {
5402:     start = A->rmap->rstart;
5403:     end   = A->rmap->rend;
5404:     PetscCall(ISCreateStride(PETSC_COMM_SELF, end - start, start, 1, &isrowa));
5405:   } else {
5406:     isrowa = *row;
5407:   }
5408:   if (!col) {
5409:     start = A->cmap->rstart;
5410:     cmap  = a->garray;
5411:     nzA   = a->A->cmap->n;
5412:     nzB   = a->B->cmap->n;
5413:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5414:     ncols = 0;
5415:     for (i = 0; i < nzB; i++) {
5416:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5417:       else break;
5418:     }
5419:     imark = i;
5420:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;
5421:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i];
5422:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &iscola));
5423:   } else iscola = *col;
5424:   if (scall != MAT_INITIAL_MATRIX) {
5425:     PetscCall(PetscMalloc1(1, &aloc));
5426:     aloc[0] = *A_loc;
5427:   }
5428:   PetscCall(MatCreateSubMatrices(A, 1, &isrowa, &iscola, scall, &aloc));
5429:   if (!col) { /* attach global id of condensed columns */
5430:     PetscCall(PetscObjectCompose((PetscObject)aloc[0], "_petsc_GetLocalMatCondensed_iscol", (PetscObject)iscola));
5431:   }
5432:   *A_loc = aloc[0];
5433:   PetscCall(PetscFree(aloc));
5434:   if (!row) PetscCall(ISDestroy(&isrowa));
5435:   if (!col) PetscCall(ISDestroy(&iscola));
5436:   PetscCall(PetscLogEventEnd(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5437:   PetscFunctionReturn(PETSC_SUCCESS);
5438: }

5440: /*
5441:  * Create a sequential AIJ matrix based on row indices. a whole column is extracted once a row is matched.
5442:  * Row could be local or remote.The routine is designed to be scalable in memory so that nothing is based
5443:  * on a global size.
5444:  * */
5445: static PetscErrorCode MatCreateSeqSubMatrixWithRows_Private(Mat P, IS rows, Mat *P_oth)
5446: {
5447:   Mat_MPIAIJ            *p  = (Mat_MPIAIJ *)P->data;
5448:   Mat_SeqAIJ            *pd = (Mat_SeqAIJ *)p->A->data, *po = (Mat_SeqAIJ *)p->B->data, *p_oth;
5449:   PetscInt               plocalsize, nrows, *ilocal, *oilocal, i, lidx, *nrcols, *nlcols, ncol;
5450:   PetscMPIInt            owner;
5451:   PetscSFNode           *iremote, *oiremote;
5452:   const PetscInt        *lrowindices;
5453:   PetscSF                sf, osf;
5454:   PetscInt               pcstart, *roffsets, *loffsets, *pnnz, j;
5455:   PetscInt               ontotalcols, dntotalcols, ntotalcols, nout;
5456:   MPI_Comm               comm;
5457:   ISLocalToGlobalMapping mapping;
5458:   const PetscScalar     *pd_a, *po_a;

5460:   PetscFunctionBegin;
5461:   PetscCall(PetscObjectGetComm((PetscObject)P, &comm));
5462:   /* plocalsize is the number of roots
5463:    * nrows is the number of leaves
5464:    * */
5465:   PetscCall(MatGetLocalSize(P, &plocalsize, NULL));
5466:   PetscCall(ISGetLocalSize(rows, &nrows));
5467:   PetscCall(PetscCalloc1(nrows, &iremote));
5468:   PetscCall(ISGetIndices(rows, &lrowindices));
5469:   for (i = 0; i < nrows; i++) {
5470:     /* Find a remote index and an owner for a row
5471:      * The row could be local or remote
5472:      * */
5473:     owner = 0;
5474:     lidx  = 0;
5475:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, &lidx));
5476:     iremote[i].index = lidx;
5477:     iremote[i].rank  = owner;
5478:   }
5479:   /* Create SF to communicate how many nonzero columns for each row */
5480:   PetscCall(PetscSFCreate(comm, &sf));
5481:   /* SF will figure out the number of nonzero columns for each row, and their
5482:    * offsets
5483:    * */
5484:   PetscCall(PetscSFSetGraph(sf, plocalsize, nrows, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5485:   PetscCall(PetscSFSetFromOptions(sf));
5486:   PetscCall(PetscSFSetUp(sf));

5488:   PetscCall(PetscCalloc1(2 * (plocalsize + 1), &roffsets));
5489:   PetscCall(PetscCalloc1(2 * plocalsize, &nrcols));
5490:   PetscCall(PetscCalloc1(nrows, &pnnz));
5491:   roffsets[0] = 0;
5492:   roffsets[1] = 0;
5493:   for (i = 0; i < plocalsize; i++) {
5494:     /* diagonal */
5495:     nrcols[i * 2 + 0] = pd->i[i + 1] - pd->i[i];
5496:     /* off-diagonal */
5497:     nrcols[i * 2 + 1] = po->i[i + 1] - po->i[i];
5498:     /* compute offsets so that we relative location for each row */
5499:     roffsets[(i + 1) * 2 + 0] = roffsets[i * 2 + 0] + nrcols[i * 2 + 0];
5500:     roffsets[(i + 1) * 2 + 1] = roffsets[i * 2 + 1] + nrcols[i * 2 + 1];
5501:   }
5502:   PetscCall(PetscCalloc1(2 * nrows, &nlcols));
5503:   PetscCall(PetscCalloc1(2 * nrows, &loffsets));
5504:   /* 'r' means root, and 'l' means leaf */
5505:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5506:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5507:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5508:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5509:   PetscCall(PetscSFDestroy(&sf));
5510:   PetscCall(PetscFree(roffsets));
5511:   PetscCall(PetscFree(nrcols));
5512:   dntotalcols = 0;
5513:   ontotalcols = 0;
5514:   ncol        = 0;
5515:   for (i = 0; i < nrows; i++) {
5516:     pnnz[i] = nlcols[i * 2 + 0] + nlcols[i * 2 + 1];
5517:     ncol    = PetscMax(pnnz[i], ncol);
5518:     /* diagonal */
5519:     dntotalcols += nlcols[i * 2 + 0];
5520:     /* off-diagonal */
5521:     ontotalcols += nlcols[i * 2 + 1];
5522:   }
5523:   /* We do not need to figure the right number of columns
5524:    * since all the calculations will be done by going through the raw data
5525:    * */
5526:   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nrows, ncol, 0, pnnz, P_oth));
5527:   PetscCall(MatSetUp(*P_oth));
5528:   PetscCall(PetscFree(pnnz));
5529:   p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5530:   /* diagonal */
5531:   PetscCall(PetscCalloc1(dntotalcols, &iremote));
5532:   /* off-diagonal */
5533:   PetscCall(PetscCalloc1(ontotalcols, &oiremote));
5534:   /* diagonal */
5535:   PetscCall(PetscCalloc1(dntotalcols, &ilocal));
5536:   /* off-diagonal */
5537:   PetscCall(PetscCalloc1(ontotalcols, &oilocal));
5538:   dntotalcols = 0;
5539:   ontotalcols = 0;
5540:   ntotalcols  = 0;
5541:   for (i = 0; i < nrows; i++) {
5542:     owner = 0;
5543:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, NULL));
5544:     /* Set iremote for diag matrix */
5545:     for (j = 0; j < nlcols[i * 2 + 0]; j++) {
5546:       iremote[dntotalcols].index = loffsets[i * 2 + 0] + j;
5547:       iremote[dntotalcols].rank  = owner;
5548:       /* P_oth is seqAIJ so that ilocal need to point to the first part of memory */
5549:       ilocal[dntotalcols++] = ntotalcols++;
5550:     }
5551:     /* off-diagonal */
5552:     for (j = 0; j < nlcols[i * 2 + 1]; j++) {
5553:       oiremote[ontotalcols].index = loffsets[i * 2 + 1] + j;
5554:       oiremote[ontotalcols].rank  = owner;
5555:       oilocal[ontotalcols++]      = ntotalcols++;
5556:     }
5557:   }
5558:   PetscCall(ISRestoreIndices(rows, &lrowindices));
5559:   PetscCall(PetscFree(loffsets));
5560:   PetscCall(PetscFree(nlcols));
5561:   PetscCall(PetscSFCreate(comm, &sf));
5562:   /* P serves as roots and P_oth is leaves
5563:    * Diag matrix
5564:    * */
5565:   PetscCall(PetscSFSetGraph(sf, pd->i[plocalsize], dntotalcols, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5566:   PetscCall(PetscSFSetFromOptions(sf));
5567:   PetscCall(PetscSFSetUp(sf));

5569:   PetscCall(PetscSFCreate(comm, &osf));
5570:   /* off-diagonal */
5571:   PetscCall(PetscSFSetGraph(osf, po->i[plocalsize], ontotalcols, oilocal, PETSC_OWN_POINTER, oiremote, PETSC_OWN_POINTER));
5572:   PetscCall(PetscSFSetFromOptions(osf));
5573:   PetscCall(PetscSFSetUp(osf));
5574:   PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5575:   PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5576:   /* operate on the matrix internal data to save memory */
5577:   PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5578:   PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5579:   PetscCall(MatGetOwnershipRangeColumn(P, &pcstart, NULL));
5580:   /* Convert to global indices for diag matrix */
5581:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] += pcstart;
5582:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5583:   /* We want P_oth store global indices */
5584:   PetscCall(ISLocalToGlobalMappingCreate(comm, 1, p->B->cmap->n, p->garray, PETSC_COPY_VALUES, &mapping));
5585:   /* Use memory scalable approach */
5586:   PetscCall(ISLocalToGlobalMappingSetType(mapping, ISLOCALTOGLOBALMAPPINGHASH));
5587:   PetscCall(ISLocalToGlobalMappingApply(mapping, po->i[plocalsize], po->j, po->j));
5588:   PetscCall(PetscSFBcastBegin(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5589:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5590:   /* Convert back to local indices */
5591:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] -= pcstart;
5592:   PetscCall(PetscSFBcastEnd(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5593:   nout = 0;
5594:   PetscCall(ISGlobalToLocalMappingApply(mapping, IS_GTOLM_DROP, po->i[plocalsize], po->j, &nout, po->j));
5595:   PetscCheck(nout == po->i[plocalsize], comm, PETSC_ERR_ARG_INCOMP, "n %" PetscInt_FMT " does not equal to nout %" PetscInt_FMT " ", po->i[plocalsize], nout);
5596:   PetscCall(ISLocalToGlobalMappingDestroy(&mapping));
5597:   /* Exchange values */
5598:   PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5599:   PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5600:   PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5601:   PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5602:   /* Stop PETSc from shrinking memory */
5603:   for (i = 0; i < nrows; i++) p_oth->ilen[i] = p_oth->imax[i];
5604:   PetscCall(MatAssemblyBegin(*P_oth, MAT_FINAL_ASSEMBLY));
5605:   PetscCall(MatAssemblyEnd(*P_oth, MAT_FINAL_ASSEMBLY));
5606:   /* Attach PetscSF objects to P_oth so that we can reuse it later */
5607:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "diagsf", (PetscObject)sf));
5608:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "offdiagsf", (PetscObject)osf));
5609:   PetscCall(PetscSFDestroy(&sf));
5610:   PetscCall(PetscSFDestroy(&osf));
5611:   PetscFunctionReturn(PETSC_SUCCESS);
5612: }

5614: /*
5615:  * Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5616:  * This supports MPIAIJ and MAIJ
5617:  * */
5618: PetscErrorCode MatGetBrowsOfAcols_MPIXAIJ(Mat A, Mat P, PetscInt dof, MatReuse reuse, Mat *P_oth)
5619: {
5620:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data, *p = (Mat_MPIAIJ *)P->data;
5621:   Mat_SeqAIJ *p_oth;
5622:   IS          rows, map;
5623:   PetscHMapI  hamp;
5624:   PetscInt    i, htsize, *rowindices, off, *mapping, key, count;
5625:   MPI_Comm    comm;
5626:   PetscSF     sf, osf;
5627:   PetscBool   has;

5629:   PetscFunctionBegin;
5630:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5631:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, P, 0, 0));
5632:   /* If it is the first time, create an index set of off-diag nonzero columns of A,
5633:    *  and then create a submatrix (that often is an overlapping matrix)
5634:    * */
5635:   if (reuse == MAT_INITIAL_MATRIX) {
5636:     /* Use a hash table to figure out unique keys */
5637:     PetscCall(PetscHMapICreateWithSize(a->B->cmap->n, &hamp));
5638:     PetscCall(PetscCalloc1(a->B->cmap->n, &mapping));
5639:     count = 0;
5640:     /* Assume that  a->g is sorted, otherwise the following does not make sense */
5641:     for (i = 0; i < a->B->cmap->n; i++) {
5642:       key = a->garray[i] / dof;
5643:       PetscCall(PetscHMapIHas(hamp, key, &has));
5644:       if (!has) {
5645:         mapping[i] = count;
5646:         PetscCall(PetscHMapISet(hamp, key, count++));
5647:       } else {
5648:         /* Current 'i' has the same value the previous step */
5649:         mapping[i] = count - 1;
5650:       }
5651:     }
5652:     PetscCall(ISCreateGeneral(comm, a->B->cmap->n, mapping, PETSC_OWN_POINTER, &map));
5653:     PetscCall(PetscHMapIGetSize(hamp, &htsize));
5654:     PetscCheck(htsize == count, comm, PETSC_ERR_ARG_INCOMP, " Size of hash map %" PetscInt_FMT " is inconsistent with count %" PetscInt_FMT, htsize, count);
5655:     PetscCall(PetscCalloc1(htsize, &rowindices));
5656:     off = 0;
5657:     PetscCall(PetscHMapIGetKeys(hamp, &off, rowindices));
5658:     PetscCall(PetscHMapIDestroy(&hamp));
5659:     PetscCall(PetscSortInt(htsize, rowindices));
5660:     PetscCall(ISCreateGeneral(comm, htsize, rowindices, PETSC_OWN_POINTER, &rows));
5661:     /* In case, the matrix was already created but users want to recreate the matrix */
5662:     PetscCall(MatDestroy(P_oth));
5663:     PetscCall(MatCreateSeqSubMatrixWithRows_Private(P, rows, P_oth));
5664:     PetscCall(PetscObjectCompose((PetscObject)*P_oth, "aoffdiagtopothmapping", (PetscObject)map));
5665:     PetscCall(ISDestroy(&map));
5666:     PetscCall(ISDestroy(&rows));
5667:   } else if (reuse == MAT_REUSE_MATRIX) {
5668:     /* If matrix was already created, we simply update values using SF objects
5669:      * that as attached to the matrix earlier.
5670:      */
5671:     const PetscScalar *pd_a, *po_a;

5673:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "diagsf", (PetscObject *)&sf));
5674:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "offdiagsf", (PetscObject *)&osf));
5675:     PetscCheck(sf && osf, comm, PETSC_ERR_ARG_NULL, "Matrix is not initialized yet");
5676:     p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5677:     /* Update values in place */
5678:     PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5679:     PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5680:     PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5681:     PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5682:     PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5683:     PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5684:     PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5685:     PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5686:   } else SETERRQ(comm, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown reuse type");
5687:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, P, 0, 0));
5688:   PetscFunctionReturn(PETSC_SUCCESS);
5689: }

5691: /*@
5692:   MatGetBrowsOfAcols - Returns `IS` that contain rows of `B` that equal to nonzero columns of local `A`

5694:   Collective

5696:   Input Parameters:
5697: + A     - the first matrix in `MATMPIAIJ` format
5698: . B     - the second matrix in `MATMPIAIJ` format
5699: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5701:   Output Parameters:
5702: + rowb  - On input index sets of rows of B to extract (or `NULL`), modified on output
5703: . colb  - On input index sets of columns of B to extract (or `NULL`), modified on output
5704: - B_seq - the sequential matrix generated

5706:   Level: developer

5708: .seealso: `Mat`, `MATMPIAIJ`, `IS`, `MatReuse`
5709: @*/
5710: PetscErrorCode MatGetBrowsOfAcols(Mat A, Mat B, MatReuse scall, IS *rowb, IS *colb, Mat *B_seq)
5711: {
5712:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5713:   PetscInt   *idx, i, start, ncols, nzA, nzB, *cmap, imark;
5714:   IS          isrowb, iscolb;
5715:   Mat        *bseq = NULL;

5717:   PetscFunctionBegin;
5718:   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 ")",
5719:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5720:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAcols, A, B, 0, 0));

5722:   if (scall == MAT_INITIAL_MATRIX) {
5723:     start = A->cmap->rstart;
5724:     cmap  = a->garray;
5725:     nzA   = a->A->cmap->n;
5726:     nzB   = a->B->cmap->n;
5727:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5728:     ncols = 0;
5729:     for (i = 0; i < nzB; i++) { /* row < local row index */
5730:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5731:       else break;
5732:     }
5733:     imark = i;
5734:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;   /* local rows */
5735:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5736:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &isrowb));
5737:     PetscCall(ISCreateStride(PETSC_COMM_SELF, B->cmap->N, 0, 1, &iscolb));
5738:   } else {
5739:     PetscCheck(rowb && colb, PETSC_COMM_SELF, PETSC_ERR_SUP, "IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5740:     isrowb = *rowb;
5741:     iscolb = *colb;
5742:     PetscCall(PetscMalloc1(1, &bseq));
5743:     bseq[0] = *B_seq;
5744:   }
5745:   PetscCall(MatCreateSubMatrices(B, 1, &isrowb, &iscolb, scall, &bseq));
5746:   *B_seq = bseq[0];
5747:   PetscCall(PetscFree(bseq));
5748:   if (!rowb) {
5749:     PetscCall(ISDestroy(&isrowb));
5750:   } else {
5751:     *rowb = isrowb;
5752:   }
5753:   if (!colb) {
5754:     PetscCall(ISDestroy(&iscolb));
5755:   } else {
5756:     *colb = iscolb;
5757:   }
5758:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAcols, A, B, 0, 0));
5759:   PetscFunctionReturn(PETSC_SUCCESS);
5760: }

5762: // PetscClangLinter pragma disable: -fdoc-sowing-chars
5763: /*
5764:   MatGetBrowsOfAoCols_MPIAIJ - Creates a `MATSEQAIJ` matrix by taking rows of B that equal to nonzero columns
5765:   of the OFF-DIAGONAL portion of local A

5767:   Collective

5769:   Input Parameters:
5770: + A     - the first matrix in `MATMPIAIJ` format
5771: . B     - the second matrix in `MATMPIAIJ` format
5772: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5774:   Output Parameters:
5775: + startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5776: . startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5777: . bufa_ptr  - array for sending matrix values, saved for MAT_REUSE (or NULL)
5778: - B_oth     - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N

5780:   Level: developer

5782:   Developer Note:
5783:   This directly accesses information inside the VecScatter associated with the matrix-vector product
5784:   for this matrix. This is not desirable.

5786: .seealso: [](ch_mat), `Mat`, `MATMPIAIJ`
5787: */
5788: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ(Mat A, Mat B, MatReuse scall, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5789: {
5790:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
5791:   VecScatter         ctx;
5792:   MPI_Comm           comm;
5793:   const PetscMPIInt *rprocs, *sprocs;
5794:   PetscMPIInt        nrecvs, nsends;
5795:   const PetscInt    *srow, *rstarts, *sstarts;
5796:   PetscInt          *rowlen, *bufj, *bufJ, ncols = 0, aBn = a->B->cmap->n, row, *b_othi, *b_othj, *rvalues = NULL, *svalues = NULL, *cols, sbs, rbs;
5797:   PetscInt           i, j, k = 0, l, ll, nrows, *rstartsj = NULL, *sstartsj, len;
5798:   PetscScalar       *b_otha, *bufa, *bufA, *vals = NULL;
5799:   MPI_Request       *reqs = NULL, *rwaits = NULL, *swaits = NULL;
5800:   PetscMPIInt        size, tag, rank, nreqs;

5802:   PetscFunctionBegin;
5803:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5804:   PetscCallMPI(MPI_Comm_size(comm, &size));

5806:   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 ")",
5807:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5808:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, B, 0, 0));
5809:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

5811:   if (size == 1) {
5812:     startsj_s = NULL;
5813:     bufa_ptr  = NULL;
5814:     *B_oth    = NULL;
5815:     PetscFunctionReturn(PETSC_SUCCESS);
5816:   }

5818:   ctx = a->Mvctx;
5819:   tag = ((PetscObject)ctx)->tag;

5821:   PetscCall(VecScatterGetRemote_Private(ctx, PETSC_TRUE /*send*/, &nsends, &sstarts, &srow, &sprocs, &sbs));
5822:   /* rprocs[] must be ordered so that indices received from them are ordered in rvalues[], which is key to algorithms used in this subroutine */
5823:   PetscCall(VecScatterGetRemoteOrdered_Private(ctx, PETSC_FALSE /*recv*/, &nrecvs, &rstarts, NULL /*indices not needed*/, &rprocs, &rbs));
5824:   PetscCall(PetscMPIIntCast(nsends + nrecvs, &nreqs));
5825:   PetscCall(PetscMalloc1(nreqs, &reqs));
5826:   rwaits = reqs;
5827:   swaits = PetscSafePointerPlusOffset(reqs, nrecvs);

5829:   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5830:   if (scall == MAT_INITIAL_MATRIX) {
5831:     /* i-array */
5832:     /*  post receives */
5833:     if (nrecvs) PetscCall(PetscMalloc1(rbs * (rstarts[nrecvs] - rstarts[0]), &rvalues)); /* rstarts can be NULL when nrecvs=0 */
5834:     for (i = 0; i < nrecvs; i++) {
5835:       rowlen = rvalues + rstarts[i] * rbs;
5836:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of indices to be received */
5837:       PetscCallMPI(MPIU_Irecv(rowlen, nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5838:     }

5840:     /* pack the outgoing message */
5841:     PetscCall(PetscMalloc2(nsends + 1, &sstartsj, nrecvs + 1, &rstartsj));

5843:     sstartsj[0] = 0;
5844:     rstartsj[0] = 0;
5845:     len         = 0; /* total length of j or a array to be sent */
5846:     if (nsends) {
5847:       k = sstarts[0]; /* ATTENTION: sstarts[0] and rstarts[0] are not necessarily zero */
5848:       PetscCall(PetscMalloc1(sbs * (sstarts[nsends] - sstarts[0]), &svalues));
5849:     }
5850:     for (i = 0; i < nsends; i++) {
5851:       rowlen = svalues + (sstarts[i] - sstarts[0]) * sbs;
5852:       nrows  = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5853:       for (j = 0; j < nrows; j++) {
5854:         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5855:         for (l = 0; l < sbs; l++) {
5856:           PetscCall(MatGetRow_MPIAIJ(B, row + l, &ncols, NULL, NULL)); /* rowlength */

5858:           rowlen[j * sbs + l] = ncols;

5860:           len += ncols;
5861:           PetscCall(MatRestoreRow_MPIAIJ(B, row + l, &ncols, NULL, NULL));
5862:         }
5863:         k++;
5864:       }
5865:       PetscCallMPI(MPIU_Isend(rowlen, nrows * sbs, MPIU_INT, sprocs[i], tag, comm, swaits + i));

5867:       sstartsj[i + 1] = len; /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5868:     }
5869:     /* recvs and sends of i-array are completed */
5870:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5871:     PetscCall(PetscFree(svalues));

5873:     /* allocate buffers for sending j and a arrays */
5874:     PetscCall(PetscMalloc1(len, &bufj));
5875:     PetscCall(PetscMalloc1(len, &bufa));

5877:     /* create i-array of B_oth */
5878:     PetscCall(PetscMalloc1(aBn + 1, &b_othi));

5880:     b_othi[0] = 0;
5881:     len       = 0; /* total length of j or a array to be received */
5882:     k         = 0;
5883:     for (i = 0; i < nrecvs; i++) {
5884:       rowlen = rvalues + (rstarts[i] - rstarts[0]) * rbs;
5885:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of rows to be received */
5886:       for (j = 0; j < nrows; j++) {
5887:         b_othi[k + 1] = b_othi[k] + rowlen[j];
5888:         PetscCall(PetscIntSumError(rowlen[j], len, &len));
5889:         k++;
5890:       }
5891:       rstartsj[i + 1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5892:     }
5893:     PetscCall(PetscFree(rvalues));

5895:     /* allocate space for j and a arrays of B_oth */
5896:     PetscCall(PetscMalloc1(b_othi[aBn], &b_othj));
5897:     PetscCall(PetscMalloc1(b_othi[aBn], &b_otha));

5899:     /* j-array */
5900:     /*  post receives of j-array */
5901:     for (i = 0; i < nrecvs; i++) {
5902:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5903:       PetscCallMPI(MPIU_Irecv(PetscSafePointerPlusOffset(b_othj, rstartsj[i]), nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5904:     }

5906:     /* pack the outgoing message j-array */
5907:     if (nsends) k = sstarts[0];
5908:     for (i = 0; i < nsends; i++) {
5909:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5910:       bufJ  = PetscSafePointerPlusOffset(bufj, sstartsj[i]);
5911:       for (j = 0; j < nrows; j++) {
5912:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5913:         for (ll = 0; ll < sbs; ll++) {
5914:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5915:           for (l = 0; l < ncols; l++) *bufJ++ = cols[l];
5916:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5917:         }
5918:       }
5919:       PetscCallMPI(MPIU_Isend(PetscSafePointerPlusOffset(bufj, sstartsj[i]), sstartsj[i + 1] - sstartsj[i], MPIU_INT, sprocs[i], tag, comm, swaits + i));
5920:     }

5922:     /* recvs and sends of j-array are completed */
5923:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5924:   } else if (scall == MAT_REUSE_MATRIX) {
5925:     sstartsj = *startsj_s;
5926:     rstartsj = *startsj_r;
5927:     bufa     = *bufa_ptr;
5928:     PetscCall(MatSeqAIJGetArrayWrite(*B_oth, &b_otha));
5929:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not possess an object container");

5931:   /* a-array */
5932:   /*  post receives of a-array */
5933:   for (i = 0; i < nrecvs; i++) {
5934:     nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5935:     PetscCallMPI(MPIU_Irecv(PetscSafePointerPlusOffset(b_otha, rstartsj[i]), nrows, MPIU_SCALAR, rprocs[i], tag, comm, rwaits + i));
5936:   }

5938:   /* pack the outgoing message a-array */
5939:   if (nsends) k = sstarts[0];
5940:   for (i = 0; i < nsends; i++) {
5941:     nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5942:     bufA  = PetscSafePointerPlusOffset(bufa, sstartsj[i]);
5943:     for (j = 0; j < nrows; j++) {
5944:       row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5945:       for (ll = 0; ll < sbs; ll++) {
5946:         PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5947:         for (l = 0; l < ncols; l++) *bufA++ = vals[l];
5948:         PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5949:       }
5950:     }
5951:     PetscCallMPI(MPIU_Isend(PetscSafePointerPlusOffset(bufa, sstartsj[i]), sstartsj[i + 1] - sstartsj[i], MPIU_SCALAR, sprocs[i], tag, comm, swaits + i));
5952:   }
5953:   /* recvs and sends of a-array are completed */
5954:   if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5955:   PetscCall(PetscFree(reqs));

5957:   if (scall == MAT_INITIAL_MATRIX) {
5958:     Mat_SeqAIJ *b_oth;

5960:     /* put together the new matrix */
5961:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, aBn, B->cmap->N, b_othi, b_othj, b_otha, B_oth));

5963:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5964:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5965:     b_oth          = (Mat_SeqAIJ *)(*B_oth)->data;
5966:     b_oth->free_a  = PETSC_TRUE;
5967:     b_oth->free_ij = PETSC_TRUE;
5968:     b_oth->nonew   = 0;

5970:     PetscCall(PetscFree(bufj));
5971:     if (!startsj_s || !bufa_ptr) {
5972:       PetscCall(PetscFree2(sstartsj, rstartsj));
5973:       PetscCall(PetscFree(bufa_ptr));
5974:     } else {
5975:       *startsj_s = sstartsj;
5976:       *startsj_r = rstartsj;
5977:       *bufa_ptr  = bufa;
5978:     }
5979:   } else if (scall == MAT_REUSE_MATRIX) {
5980:     PetscCall(MatSeqAIJRestoreArrayWrite(*B_oth, &b_otha));
5981:   }

5983:   PetscCall(VecScatterRestoreRemote_Private(ctx, PETSC_TRUE, &nsends, &sstarts, &srow, &sprocs, &sbs));
5984:   PetscCall(VecScatterRestoreRemoteOrdered_Private(ctx, PETSC_FALSE, &nrecvs, &rstarts, NULL, &rprocs, &rbs));
5985:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, B, 0, 0));
5986:   PetscFunctionReturn(PETSC_SUCCESS);
5987: }

5989: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat, MatType, MatReuse, Mat *);
5990: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat, MatType, MatReuse, Mat *);
5991: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJSELL(Mat, MatType, MatReuse, Mat *);
5992: #if PetscDefined(HAVE_MKL_SPARSE)
5993: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJMKL(Mat, MatType, MatReuse, Mat *);
5994: #endif
5995: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIBAIJ(Mat, MatType, MatReuse, Mat *);
5996: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat, MatType, MatReuse, Mat *);
5997: #if PetscDefined(HAVE_ELEMENTAL)
5998: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat, MatType, MatReuse, Mat *);
5999: #endif
6000: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
6001: PETSC_INTERN PetscErrorCode MatConvert_AIJ_ScaLAPACK(Mat, MatType, MatReuse, Mat *);
6002: #endif
6003: #if PetscDefined(HAVE_HYPRE)
6004: PETSC_INTERN PetscErrorCode MatConvert_AIJ_HYPRE(Mat, MatType, MatReuse, Mat *);
6005: #endif
6006: #if PetscDefined(HAVE_CUDA)
6007: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
6008: #endif
6009: #if PetscDefined(HAVE_HIP)
6010: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJHIPSPARSE(Mat, MatType, MatReuse, Mat *);
6011: #endif
6012: #if PetscDefined(HAVE_KOKKOS_KERNELS)
6013: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJKokkos(Mat, MatType, MatReuse, Mat *);
6014: #endif
6015: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISELL(Mat, MatType, MatReuse, Mat *);
6016: PETSC_INTERN PetscErrorCode MatConvert_XAIJ_IS(Mat, MatType, MatReuse, Mat *);
6017: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_IS_XAIJ(Mat);

6019: /*
6020:     Computes (B'*A')' since computing B*A directly is untenable

6022:                n                       p                          p
6023:         [             ]       [             ]         [                 ]
6024:       m [      A      ]  *  n [       B     ]   =   m [         C       ]
6025:         [             ]       [             ]         [                 ]

6027: */
6028: static PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A, Mat B, Mat C)
6029: {
6030:   Mat At, Bt, Ct;

6032:   PetscFunctionBegin;
6033:   PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
6034:   PetscCall(MatTranspose(B, MAT_INITIAL_MATRIX, &Bt));
6035:   PetscCall(MatMatMult(Bt, At, MAT_INITIAL_MATRIX, PETSC_CURRENT, &Ct));
6036:   PetscCall(MatDestroy(&At));
6037:   PetscCall(MatDestroy(&Bt));
6038:   PetscCall(MatTransposeSetPrecursor(Ct, C));
6039:   PetscCall(MatTranspose(Ct, MAT_REUSE_MATRIX, &C));
6040:   PetscCall(MatDestroy(&Ct));
6041:   PetscFunctionReturn(PETSC_SUCCESS);
6042: }

6044: static PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A, Mat B, PetscReal fill, Mat C)
6045: {
6046:   PetscBool cisdense;

6048:   PetscFunctionBegin;
6049:   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);
6050:   PetscCall(MatSetSizes(C, A->rmap->n, B->cmap->n, A->rmap->N, B->cmap->N));
6051:   PetscCall(MatSetBlockSizesFromMats(C, A, B));
6052:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATMPIDENSE, MATMPIDENSECUDA, MATMPIDENSEHIP, ""));
6053:   if (!cisdense) PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
6054:   PetscCall(MatSetUp(C));

6056:   C->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
6057:   PetscFunctionReturn(PETSC_SUCCESS);
6058: }

6060: static PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ_AB(Mat C)
6061: {
6062:   Mat_Product *product = C->product;
6063:   Mat          A = product->A, B = product->B;

6065:   PetscFunctionBegin;
6066:   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 ")",
6067:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
6068:   C->ops->matmultsymbolic = MatMatMultSymbolic_MPIDense_MPIAIJ;
6069:   C->ops->productsymbolic = MatProductSymbolic_AB;
6070:   PetscFunctionReturn(PETSC_SUCCESS);
6071: }

6073: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ(Mat C)
6074: {
6075:   Mat_Product *product = C->product;

6077:   PetscFunctionBegin;
6078:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_MPIDense_MPIAIJ_AB(C));
6079:   PetscFunctionReturn(PETSC_SUCCESS);
6080: }

6082: /*
6083:    Merge two sets of sorted nonzeros and return a CSR for the merged (sequential) matrix

6085:   Input Parameters:

6087:     j1,rowBegin1,rowEnd1,jmap1: describe the first set of nonzeros (Set1)
6088:     j2,rowBegin2,rowEnd2,jmap2: describe the second set of nonzeros (Set2)

6090:     mat: both sets' nonzeros are on m rows, where m is the number of local rows of the matrix mat

6092:     For Set1, j1[] contains column indices of the nonzeros.
6093:     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
6094:     respectively (note rowEnd1[k] is not necessarily equal to rwoBegin1[k+1]). Indices in this range of j1[] are sorted,
6095:     but might have repeats. jmap1[t+1] - jmap1[t] is the number of repeats for the t-th unique nonzero in Set1.

6097:     Similar for Set2.

6099:     This routine merges the two sets of nonzeros row by row and removes repeats.

6101:   Output Parameters: (memory is allocated by the caller)

6103:     i[],j[]: the CSR of the merged matrix, which has m rows.
6104:     imap1[]: the k-th unique nonzero in Set1 (k=0,1,...) corresponds to imap1[k]-th unique nonzero in the merged matrix.
6105:     imap2[]: similar to imap1[], but for Set2.
6106:     Note we order nonzeros row-by-row and from left to right.
6107: */
6108: 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[])
6109: {
6110:   PetscInt   r, m; /* Row index of mat */
6111:   PetscCount t, t1, t2, b1, e1, b2, e2;

6113:   PetscFunctionBegin;
6114:   PetscCall(MatGetLocalSize(mat, &m, NULL));
6115:   t1 = t2 = t = 0; /* Count unique nonzeros of in Set1, Set1 and the merged respectively */
6116:   i[0]        = 0;
6117:   for (r = 0; r < m; r++) { /* Do row by row merging */
6118:     b1 = rowBegin1[r];
6119:     e1 = rowEnd1[r];
6120:     b2 = rowBegin2[r];
6121:     e2 = rowEnd2[r];
6122:     while (b1 < e1 && b2 < e2) {
6123:       if (j1[b1] == j2[b2]) { /* Same column index and hence same nonzero */
6124:         j[t]      = j1[b1];
6125:         imap1[t1] = t;
6126:         imap2[t2] = t;
6127:         b1 += jmap1[t1 + 1] - jmap1[t1]; /* Jump to next unique local nonzero */
6128:         b2 += jmap2[t2 + 1] - jmap2[t2]; /* Jump to next unique remote nonzero */
6129:         t1++;
6130:         t2++;
6131:         t++;
6132:       } else if (j1[b1] < j2[b2]) {
6133:         j[t]      = j1[b1];
6134:         imap1[t1] = t;
6135:         b1 += jmap1[t1 + 1] - jmap1[t1];
6136:         t1++;
6137:         t++;
6138:       } else {
6139:         j[t]      = j2[b2];
6140:         imap2[t2] = t;
6141:         b2 += jmap2[t2 + 1] - jmap2[t2];
6142:         t2++;
6143:         t++;
6144:       }
6145:     }
6146:     /* Merge the remaining in either j1[] or j2[] */
6147:     while (b1 < e1) {
6148:       j[t]      = j1[b1];
6149:       imap1[t1] = t;
6150:       b1 += jmap1[t1 + 1] - jmap1[t1];
6151:       t1++;
6152:       t++;
6153:     }
6154:     while (b2 < e2) {
6155:       j[t]      = j2[b2];
6156:       imap2[t2] = t;
6157:       b2 += jmap2[t2 + 1] - jmap2[t2];
6158:       t2++;
6159:       t++;
6160:     }
6161:     PetscCall(PetscIntCast(t, i + r + 1));
6162:   }
6163:   PetscFunctionReturn(PETSC_SUCCESS);
6164: }

6166: /*
6167:   Split nonzeros in a block of local rows into two subsets: those in the diagonal block and those in the off-diagonal block

6169:   Input Parameters:
6170:     mat: an MPI matrix that provides row and column layout information for splitting. Let's say its number of local rows is m.
6171:     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[]
6172:       respectively, along with a permutation array perm[]. Length of the i[],j[],perm[] arrays is n.

6174:       i[] is already sorted, but within a row, j[] is not sorted and might have repeats.
6175:       i[] might contain negative indices at the beginning, which means the corresponding entries should be ignored in the splitting.

6177:   Output Parameters:
6178:     j[],perm[]: the routine needs to sort j[] within each row along with perm[].
6179:     rowBegin[],rowMid[],rowEnd[]: of length m, and the memory is preallocated and zeroed by the caller.
6180:       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,
6181:       and [rowMid[r],rowEnd[r]) point to begin/end entries of row r of the off-diagonal block.

6183:     Aperm[],Ajmap[],Atot,Annz: Arrays are allocated by this routine.
6184:       Atot: number of entries belonging to the diagonal block.
6185:       Annz: number of unique nonzeros belonging to the diagonal block.
6186:       Aperm[Atot] stores values from perm[] for entries belonging to the diagonal block. Length of Aperm[] is Atot, though it may also count
6187:         repeats (i.e., same 'i,j' pair).
6188:       Ajmap[Annz+1] stores the number of repeats of each unique entry belonging to the diagonal block. More precisely, Ajmap[t+1] - Ajmap[t]
6189:         is the number of repeats for the t-th unique entry in the diagonal block. Ajmap[0] is always 0.

6191:       Atot: number of entries belonging to the diagonal block
6192:       Annz: number of unique nonzeros belonging to the diagonal block.

6194:     Bperm[], Bjmap[], Btot, Bnnz are similar but for the off-diagonal block.

6196:     Aperm[],Bperm[],Ajmap[] and Bjmap[] are allocated separately by this routine with PetscMalloc1().
6197: */
6198: 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_)
6199: {
6200:   PetscInt    cstart, cend, rstart, rend, row, col;
6201:   PetscCount  Atot = 0, Btot = 0; /* Total number of nonzeros in the diagonal and off-diagonal blocks */
6202:   PetscCount  Annz = 0, Bnnz = 0; /* Number of unique nonzeros in the diagonal and off-diagonal blocks */
6203:   PetscCount  k, m, p, q, r, s, mid;
6204:   PetscCount *Aperm, *Bperm, *Ajmap, *Bjmap;

6206:   PetscFunctionBegin;
6207:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6208:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6209:   m = rend - rstart;

6211:   /* Skip negative rows */
6212:   for (k = 0; k < n; k++)
6213:     if (i[k] >= 0) break;

6215:   /* Process [k,n): sort and partition each local row into diag and offdiag portions,
6216:      fill rowBegin[], rowMid[], rowEnd[], and count Atot, Btot, Annz, Bnnz.
6217:   */
6218:   while (k < n) {
6219:     row = i[k];
6220:     /* Entries in [k,s) are in one row. Shift diagonal block col indices so that diag is ahead of offdiag after sorting the row */
6221:     for (s = k; s < n; s++)
6222:       if (i[s] != row) break;

6224:     /* Shift diag columns to range of [-PETSC_INT_MAX, -1] */
6225:     for (p = k; p < s; p++) {
6226:       if (j[p] >= cstart && j[p] < cend) j[p] -= PETSC_INT_MAX;
6227:     }
6228:     PetscCall(PetscSortIntWithCountArray(s - k, j + k, perm + k));
6229:     PetscCall(PetscSortedIntUpperBound(j, k, s, -1, &mid)); /* Separate [k,s) into [k,mid) for diag and [mid,s) for offdiag */
6230:     rowBegin[row - rstart] = k;
6231:     rowMid[row - rstart]   = mid;
6232:     rowEnd[row - rstart]   = s;
6233:     PetscCheck(k == s || j[s - 1] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column index %" PetscInt_FMT " is >= matrix column size %" PetscInt_FMT, j[s - 1], mat->cmap->N);

6235:     /* Count nonzeros of this diag/offdiag row, which might have repeats */
6236:     Atot += mid - k;
6237:     Btot += s - mid;

6239:     /* Count unique nonzeros of this diag row */
6240:     for (p = k; p < mid;) {
6241:       col = j[p];
6242:       do {
6243:         j[p] += PETSC_INT_MAX; /* Revert the modified diagonal indices */
6244:         p++;
6245:       } while (p < mid && j[p] == col);
6246:       Annz++;
6247:     }

6249:     /* Count unique nonzeros of this offdiag row */
6250:     for (p = mid; p < s;) {
6251:       col = j[p];
6252:       do {
6253:         p++;
6254:       } while (p < s && j[p] == col);
6255:       Bnnz++;
6256:     }
6257:     k = s;
6258:   }

6260:   /* Allocation according to Atot, Btot, Annz, Bnnz */
6261:   PetscCall(PetscMalloc1(Atot, &Aperm));
6262:   PetscCall(PetscMalloc1(Btot, &Bperm));
6263:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap));
6264:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap));

6266:   /* Re-scan indices and copy diag/offdiag permutation indices to Aperm, Bperm and also fill Ajmap and Bjmap */
6267:   Ajmap[0] = Bjmap[0] = Atot = Btot = Annz = Bnnz = 0;
6268:   for (r = 0; r < m; r++) {
6269:     k   = rowBegin[r];
6270:     mid = rowMid[r];
6271:     s   = rowEnd[r];
6272:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Aperm, Atot), PetscSafePointerPlusOffset(perm, k), mid - k));
6273:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Bperm, Btot), PetscSafePointerPlusOffset(perm, mid), s - mid));
6274:     Atot += mid - k;
6275:     Btot += s - mid;

6277:     /* Scan column indices in this row and find out how many repeats each unique nonzero has */
6278:     for (p = k; p < mid;) {
6279:       col = j[p];
6280:       q   = p;
6281:       do {
6282:         p++;
6283:       } while (p < mid && j[p] == col);
6284:       Ajmap[Annz + 1] = Ajmap[Annz] + (p - q);
6285:       Annz++;
6286:     }

6288:     for (p = mid; p < s;) {
6289:       col = j[p];
6290:       q   = p;
6291:       do {
6292:         p++;
6293:       } while (p < s && j[p] == col);
6294:       Bjmap[Bnnz + 1] = Bjmap[Bnnz] + (p - q);
6295:       Bnnz++;
6296:     }
6297:   }
6298:   /* Output */
6299:   *Aperm_ = Aperm;
6300:   *Annz_  = Annz;
6301:   *Atot_  = Atot;
6302:   *Ajmap_ = Ajmap;
6303:   *Bperm_ = Bperm;
6304:   *Bnnz_  = Bnnz;
6305:   *Btot_  = Btot;
6306:   *Bjmap_ = Bjmap;
6307:   PetscFunctionReturn(PETSC_SUCCESS);
6308: }

6310: /*
6311:   Expand the jmap[] array to make a new one in view of nonzeros in the merged matrix

6313:   Input Parameters:
6314:     nnz1: number of unique nonzeros in a set that was used to produce imap[], jmap[]
6315:     nnz:  number of unique nonzeros in the merged matrix
6316:     imap[nnz1]: i-th nonzero in the set is the imap[i]-th nonzero in the merged matrix
6317:     jmap[nnz1+1]: i-th nonzero in the set has jmap[i+1] - jmap[i] repeats in the set

6319:   Output Parameter: (memory is allocated by the caller)
6320:     jmap_new[nnz+1]: i-th nonzero in the merged matrix has jmap_new[i+1] - jmap_new[i] repeats in the set

6322:   Example:
6323:     nnz1 = 4
6324:     nnz  = 6
6325:     imap = [1,3,4,5]
6326:     jmap = [0,3,5,6,7]
6327:    then,
6328:     jmap_new = [0,0,3,3,5,6,7]
6329: */
6330: static PetscErrorCode ExpandJmap_Internal(PetscCount nnz1, PetscCount nnz, const PetscCount imap[], const PetscCount jmap[], PetscCount jmap_new[])
6331: {
6332:   PetscCount k, p;

6334:   PetscFunctionBegin;
6335:   jmap_new[0] = 0;
6336:   p           = nnz;                /* p loops over jmap_new[] backwards */
6337:   for (k = nnz1 - 1; k >= 0; k--) { /* k loops over imap[] */
6338:     for (; p > imap[k]; p--) jmap_new[p] = jmap[k + 1];
6339:   }
6340:   for (; p >= 0; p--) jmap_new[p] = jmap[0];
6341:   PetscFunctionReturn(PETSC_SUCCESS);
6342: }

6344: static PetscErrorCode MatCOOStructDestroy_MPIAIJ(PetscCtxRt data)
6345: {
6346:   MatCOOStruct_MPIAIJ *coo = *(MatCOOStruct_MPIAIJ **)data;

6348:   PetscFunctionBegin;
6349:   PetscCall(PetscSFDestroy(&coo->sf));
6350:   PetscCall(PetscFree(coo->Aperm1));
6351:   PetscCall(PetscFree(coo->Bperm1));
6352:   PetscCall(PetscFree(coo->Ajmap1));
6353:   PetscCall(PetscFree(coo->Bjmap1));
6354:   PetscCall(PetscFree(coo->Aimap2));
6355:   PetscCall(PetscFree(coo->Bimap2));
6356:   PetscCall(PetscFree(coo->Aperm2));
6357:   PetscCall(PetscFree(coo->Bperm2));
6358:   PetscCall(PetscFree(coo->Ajmap2));
6359:   PetscCall(PetscFree(coo->Bjmap2));
6360:   PetscCall(PetscFree(coo->Cperm1));
6361:   PetscCall(PetscFree2(coo->sendbuf, coo->recvbuf));
6362:   PetscCall(PetscFree(coo));
6363:   PetscFunctionReturn(PETSC_SUCCESS);
6364: }

6366: PetscErrorCode MatSetPreallocationCOO_MPIAIJ(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
6367: {
6368:   MPI_Comm             comm;
6369:   PetscMPIInt          rank, size;
6370:   PetscInt             m, n, M, N, rstart, rend, cstart, cend; /* Sizes, indices of row/col, therefore with type PetscInt */
6371:   PetscCount           k, p, q, rem;                           /* Loop variables over coo arrays */
6372:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6373:   PetscContainer       container;
6374:   MatCOOStruct_MPIAIJ *coo;

6376:   PetscFunctionBegin;
6377:   PetscCall(PetscFree(mpiaij->garray));
6378:   PetscCall(VecDestroy(&mpiaij->lvec));
6379: #if PetscDefined(USE_CTABLE)
6380:   PetscCall(PetscHMapIDestroy(&mpiaij->colmap));
6381: #else
6382:   PetscCall(PetscFree(mpiaij->colmap));
6383: #endif
6384:   PetscCall(VecScatterDestroy(&mpiaij->Mvctx));
6385:   mat->assembled     = PETSC_FALSE;
6386:   mat->was_assembled = PETSC_FALSE;

6388:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
6389:   PetscCallMPI(MPI_Comm_size(comm, &size));
6390:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
6391:   PetscCall(PetscLayoutSetUp(mat->rmap));
6392:   PetscCall(PetscLayoutSetUp(mat->cmap));
6393:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6394:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6395:   PetscCall(MatGetLocalSize(mat, &m, &n));
6396:   PetscCall(MatGetSize(mat, &M, &N));

6398:   /* Sort (i,j) by row along with a permutation array, so that the to-be-ignored */
6399:   /* entries come first, then local rows, then remote rows.                     */
6400:   PetscCount n1 = coo_n, *perm1;
6401:   PetscInt  *i1 = coo_i, *j1 = coo_j;

6403:   PetscCall(PetscMalloc1(n1, &perm1));
6404:   for (k = 0; k < n1; k++) perm1[k] = k;

6406:   /* Manipulate indices so that entries with negative row or col indices will have smallest
6407:      row indices, local entries will have greater but negative row indices, and remote entries
6408:      will have positive row indices.
6409:   */
6410:   for (k = 0; k < n1; k++) {
6411:     if (i1[k] < 0 || j1[k] < 0) i1[k] = PETSC_INT_MIN;                /* e.g., -2^31, minimal to move them ahead */
6412:     else if (i1[k] >= rstart && i1[k] < rend) i1[k] -= PETSC_INT_MAX; /* e.g., minus 2^31-1 to shift local rows to range of [-PETSC_INT_MAX, -1] */
6413:     else {
6414:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "MAT_NO_OFF_PROC_ENTRIES is set but insert to remote rows");
6415:       if (mpiaij->donotstash) i1[k] = PETSC_INT_MIN; /* Ignore offproc entries as if they had negative indices */
6416:     }
6417:   }

6419:   /* Sort by row; after that, [0,k) have ignored entries, [k,rem) have local rows and [rem,n1) have remote rows */
6420:   PetscCall(PetscSortIntWithIntCountArrayPair(n1, i1, j1, perm1));

6422:   /* Advance k to the first entry we need to take care of */
6423:   for (k = 0; k < n1; k++)
6424:     if (i1[k] > PETSC_INT_MIN) break;
6425:   PetscCount i1start = k;

6427:   PetscCall(PetscSortedIntUpperBound(i1, k, n1, rend - 1 - PETSC_INT_MAX, &rem)); /* rem is upper bound of the last local row */
6428:   for (; k < rem; k++) i1[k] += PETSC_INT_MAX;                                    /* Revert row indices of local rows*/

6430:   PetscCheck(n1 == 0 || i1[n1 - 1] < M, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "COO row index %" PetscInt_FMT " is >= the matrix row size %" PetscInt_FMT, i1[n1 - 1], M);

6432:   /*           Send remote rows to their owner                                  */
6433:   /* Find which rows should be sent to which remote ranks*/
6434:   PetscInt        nsend = 0; /* Number of MPI ranks to send data to */
6435:   PetscMPIInt    *sendto;    /* [nsend], storing remote ranks */
6436:   PetscInt       *nentries;  /* [nsend], storing number of entries sent to remote ranks; Assume PetscInt is big enough for this count, and error if not */
6437:   const PetscInt *ranges;
6438:   PetscInt        maxNsend = size >= 128 ? 128 : size; /* Assume max 128 neighbors; realloc when needed */

6440:   PetscCall(PetscLayoutGetRanges(mat->rmap, &ranges));
6441:   PetscCall(PetscMalloc2(maxNsend, &sendto, maxNsend, &nentries));
6442:   for (k = rem; k < n1;) {
6443:     PetscMPIInt owner;
6444:     PetscInt    firstRow, lastRow;

6446:     /* Locate a row range */
6447:     firstRow = i1[k]; /* first row of this owner */
6448:     PetscCall(PetscLayoutFindOwner(mat->rmap, firstRow, &owner));
6449:     lastRow = ranges[owner + 1] - 1; /* last row of this owner */

6451:     /* Find the first index 'p' in [k,n) with i1[p] belonging to next owner */
6452:     PetscCall(PetscSortedIntUpperBound(i1, k, n1, lastRow, &p));

6454:     /* All entries in [k,p) belong to this remote owner */
6455:     if (nsend >= maxNsend) { /* Double the remote ranks arrays if not long enough */
6456:       PetscMPIInt *sendto2;
6457:       PetscInt    *nentries2;
6458:       PetscInt     maxNsend2 = (maxNsend <= size / 2) ? maxNsend * 2 : size;

6460:       PetscCall(PetscMalloc2(maxNsend2, &sendto2, maxNsend2, &nentries2));
6461:       PetscCall(PetscArraycpy(sendto2, sendto, maxNsend));
6462:       PetscCall(PetscArraycpy(nentries2, nentries, maxNsend));
6463:       PetscCall(PetscFree2(sendto, nentries));
6464:       sendto   = sendto2;
6465:       nentries = nentries2;
6466:       maxNsend = maxNsend2;
6467:     }
6468:     sendto[nsend] = owner;
6469:     PetscCall(PetscIntCast(p - k, &nentries[nsend]));
6470:     nsend++;
6471:     k = p;
6472:   }

6474:   /* Build 1st SF to know offsets on remote to send data */
6475:   PetscSF      sf1;
6476:   PetscInt     nroots = 1, nroots2 = 0;
6477:   PetscInt     nleaves = nsend, nleaves2 = 0;
6478:   PetscInt    *offsets;
6479:   PetscSFNode *iremote;

6481:   PetscCall(PetscSFCreate(comm, &sf1));
6482:   PetscCall(PetscMalloc1(nsend, &iremote));
6483:   PetscCall(PetscMalloc1(nsend, &offsets));
6484:   for (k = 0; k < nsend; k++) {
6485:     iremote[k].rank  = sendto[k];
6486:     iremote[k].index = 0;
6487:     nleaves2 += nentries[k];
6488:     PetscCheck(nleaves2 >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF leaves is too large for PetscInt");
6489:   }
6490:   PetscCall(PetscSFSetGraph(sf1, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
6491:   PetscCall(PetscSFFetchAndOpWithMemTypeBegin(sf1, MPIU_INT, PETSC_MEMTYPE_HOST, &nroots2 /*rootdata*/, PETSC_MEMTYPE_HOST, nentries /*leafdata*/, PETSC_MEMTYPE_HOST, offsets /*leafupdate*/, MPI_SUM));
6492:   PetscCall(PetscSFFetchAndOpEnd(sf1, MPIU_INT, &nroots2, nentries, offsets, MPI_SUM)); /* Would nroots2 overflow, we check offsets[] below */
6493:   PetscCall(PetscSFDestroy(&sf1));
6494:   PetscAssert(nleaves2 == n1 - rem, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nleaves2 %" PetscInt_FMT " != number of remote entries %" PetscCount_FMT, nleaves2, n1 - rem);

6496:   /* Build 2nd SF to send remote COOs to their owner */
6497:   PetscSF sf2;
6498:   nroots  = nroots2;
6499:   nleaves = nleaves2;
6500:   PetscCall(PetscSFCreate(comm, &sf2));
6501:   PetscCall(PetscSFSetFromOptions(sf2));
6502:   PetscCall(PetscMalloc1(nleaves, &iremote));
6503:   p = 0;
6504:   for (k = 0; k < nsend; k++) {
6505:     PetscCheck(offsets[k] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF roots is too large for PetscInt");
6506:     for (q = 0; q < nentries[k]; q++, p++) {
6507:       iremote[p].rank = sendto[k];
6508:       PetscCall(PetscIntCast(offsets[k] + q, &iremote[p].index));
6509:     }
6510:   }
6511:   PetscCall(PetscSFSetGraph(sf2, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

6513:   /* Send the remote COOs to their owner */
6514:   PetscInt    n2 = nroots, *i2, *j2; /* Buffers for received COOs from other ranks, along with a permutation array */
6515:   PetscCount *perm2;                 /* Though PetscInt is enough for remote entries, we use PetscCount here as we want to reuse MatSplitEntries_Internal() */
6516:   PetscCall(PetscMalloc3(n2, &i2, n2, &j2, n2, &perm2));
6517:   PetscAssert(rem == 0 || i1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6518:   PetscAssert(rem == 0 || j1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6519:   PetscInt *i1prem = PetscSafePointerPlusOffset(i1, rem);
6520:   PetscInt *j1prem = PetscSafePointerPlusOffset(j1, rem);
6521:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, i1prem, PETSC_MEMTYPE_HOST, i2, MPI_REPLACE));
6522:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, i1prem, i2, MPI_REPLACE));
6523:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, j1prem, PETSC_MEMTYPE_HOST, j2, MPI_REPLACE));
6524:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, j1prem, j2, MPI_REPLACE));

6526:   PetscCall(PetscFree(offsets));
6527:   PetscCall(PetscFree2(sendto, nentries));

6529:   /* Sort received COOs by row along with the permutation array     */
6530:   for (k = 0; k < n2; k++) perm2[k] = k;
6531:   PetscCall(PetscSortIntWithIntCountArrayPair(n2, i2, j2, perm2));

6533:   /* sf2 only sends contiguous leafdata to contiguous rootdata. We record the permutation which will be used to fill leafdata */
6534:   PetscCount *Cperm1;
6535:   PetscAssert(rem == 0 || perm1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6536:   PetscCount *perm1prem = PetscSafePointerPlusOffset(perm1, rem);
6537:   PetscCall(PetscMalloc1(nleaves, &Cperm1));
6538:   PetscCall(PetscArraycpy(Cperm1, perm1prem, nleaves));

6540:   /* Support for HYPRE matrices, kind of a hack.
6541:      Swap min column with diagonal so that diagonal values will go first */
6542:   PetscBool hypre;
6543:   PetscCall(PetscStrcmp("_internal_COO_mat_for_hypre", ((PetscObject)mat)->name, &hypre));
6544:   if (hypre) {
6545:     PetscInt *minj;
6546:     PetscBT   hasdiag;

6548:     PetscCall(PetscBTCreate(m, &hasdiag));
6549:     PetscCall(PetscMalloc1(m, &minj));
6550:     for (k = 0; k < m; k++) minj[k] = PETSC_INT_MAX;
6551:     for (k = i1start; k < rem; k++) {
6552:       if (j1[k] < cstart || j1[k] >= cend) continue;
6553:       const PetscInt rindex = i1[k] - rstart;
6554:       if ((j1[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6555:       minj[rindex] = PetscMin(minj[rindex], j1[k]);
6556:     }
6557:     for (k = 0; k < n2; k++) {
6558:       if (j2[k] < cstart || j2[k] >= cend) continue;
6559:       const PetscInt rindex = i2[k] - rstart;
6560:       if ((j2[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6561:       minj[rindex] = PetscMin(minj[rindex], j2[k]);
6562:     }
6563:     for (k = i1start; k < rem; k++) {
6564:       const PetscInt rindex = i1[k] - rstart;
6565:       if (j1[k] < cstart || j1[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6566:       if (j1[k] == minj[rindex]) j1[k] = i1[k] + (cstart - rstart);
6567:       else if ((j1[k] - cstart) == rindex) j1[k] = minj[rindex];
6568:     }
6569:     for (k = 0; k < n2; k++) {
6570:       const PetscInt rindex = i2[k] - rstart;
6571:       if (j2[k] < cstart || j2[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6572:       if (j2[k] == minj[rindex]) j2[k] = i2[k] + (cstart - rstart);
6573:       else if ((j2[k] - cstart) == rindex) j2[k] = minj[rindex];
6574:     }
6575:     PetscCall(PetscBTDestroy(&hasdiag));
6576:     PetscCall(PetscFree(minj));
6577:   }

6579:   /* Split local COOs and received COOs into diag/offdiag portions */
6580:   PetscCount *rowBegin1, *rowMid1, *rowEnd1;
6581:   PetscCount *Ajmap1, *Aperm1, *Bjmap1, *Bperm1;
6582:   PetscCount  Annz1, Bnnz1, Atot1, Btot1;
6583:   PetscCount *rowBegin2, *rowMid2, *rowEnd2;
6584:   PetscCount *Ajmap2, *Aperm2, *Bjmap2, *Bperm2;
6585:   PetscCount  Annz2, Bnnz2, Atot2, Btot2;

6587:   PetscCall(PetscCalloc3(m, &rowBegin1, m, &rowMid1, m, &rowEnd1));
6588:   PetscCall(PetscCalloc3(m, &rowBegin2, m, &rowMid2, m, &rowEnd2));
6589:   PetscCall(MatSplitEntries_Internal(mat, rem, i1, j1, perm1, rowBegin1, rowMid1, rowEnd1, &Atot1, &Aperm1, &Annz1, &Ajmap1, &Btot1, &Bperm1, &Bnnz1, &Bjmap1));
6590:   PetscCall(MatSplitEntries_Internal(mat, n2, i2, j2, perm2, rowBegin2, rowMid2, rowEnd2, &Atot2, &Aperm2, &Annz2, &Ajmap2, &Btot2, &Bperm2, &Bnnz2, &Bjmap2));

6592:   /* Merge local COOs with received COOs: diag with diag, offdiag with offdiag */
6593:   PetscInt *Ai, *Bi;
6594:   PetscInt *Aj, *Bj;

6596:   PetscCall(PetscMalloc1(m + 1, &Ai));
6597:   PetscCall(PetscMalloc1(m + 1, &Bi));
6598:   PetscCall(PetscMalloc1(Annz1 + Annz2, &Aj)); /* Since local and remote entries might have dups, we might allocate excess memory */
6599:   PetscCall(PetscMalloc1(Bnnz1 + Bnnz2, &Bj));

6601:   PetscCount *Aimap1, *Bimap1, *Aimap2, *Bimap2;
6602:   PetscCall(PetscMalloc1(Annz1, &Aimap1));
6603:   PetscCall(PetscMalloc1(Bnnz1, &Bimap1));
6604:   PetscCall(PetscMalloc1(Annz2, &Aimap2));
6605:   PetscCall(PetscMalloc1(Bnnz2, &Bimap2));

6607:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowBegin1, rowMid1, rowBegin2, rowMid2, Ajmap1, Ajmap2, Aimap1, Aimap2, Ai, Aj));
6608:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowMid1, rowEnd1, rowMid2, rowEnd2, Bjmap1, Bjmap2, Bimap1, Bimap2, Bi, Bj));

6610:   /* Expand Ajmap1/Bjmap1 to make them based off nonzeros in A/B, since we     */
6611:   /* expect nonzeros in A/B most likely have local contributing entries        */
6612:   PetscInt    Annz = Ai[m];
6613:   PetscInt    Bnnz = Bi[m];
6614:   PetscCount *Ajmap1_new, *Bjmap1_new;

6616:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap1_new));
6617:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap1_new));

6619:   PetscCall(ExpandJmap_Internal(Annz1, Annz, Aimap1, Ajmap1, Ajmap1_new));
6620:   PetscCall(ExpandJmap_Internal(Bnnz1, Bnnz, Bimap1, Bjmap1, Bjmap1_new));

6622:   PetscCall(PetscFree(Aimap1));
6623:   PetscCall(PetscFree(Ajmap1));
6624:   PetscCall(PetscFree(Bimap1));
6625:   PetscCall(PetscFree(Bjmap1));
6626:   PetscCall(PetscFree3(rowBegin1, rowMid1, rowEnd1));
6627:   PetscCall(PetscFree3(rowBegin2, rowMid2, rowEnd2));
6628:   PetscCall(PetscFree(perm1));
6629:   PetscCall(PetscFree3(i2, j2, perm2));

6631:   Ajmap1 = Ajmap1_new;
6632:   Bjmap1 = Bjmap1_new;

6634:   /* Reallocate Aj, Bj once we know actual numbers of unique nonzeros in A and B */
6635:   if (Annz < Annz1 + Annz2) {
6636:     PetscInt *Aj_new;
6637:     PetscCall(PetscMalloc1(Annz, &Aj_new));
6638:     PetscCall(PetscArraycpy(Aj_new, Aj, Annz));
6639:     PetscCall(PetscFree(Aj));
6640:     Aj = Aj_new;
6641:   }

6643:   if (Bnnz < Bnnz1 + Bnnz2) {
6644:     PetscInt *Bj_new;
6645:     PetscCall(PetscMalloc1(Bnnz, &Bj_new));
6646:     PetscCall(PetscArraycpy(Bj_new, Bj, Bnnz));
6647:     PetscCall(PetscFree(Bj));
6648:     Bj = Bj_new;
6649:   }

6651:   /* Create new submatrices for on-process and off-process coupling                  */
6652:   PetscScalar *Aa, *Ba;
6653:   MatType      rtype;
6654:   Mat_SeqAIJ  *a, *b;
6655:   PetscCall(PetscCalloc1(Annz, &Aa)); /* Zero matrix on device */
6656:   PetscCall(PetscCalloc1(Bnnz, &Ba));
6657:   /* make Aj[] local, i.e, based off the start column of the diagonal portion */
6658:   if (cstart) {
6659:     for (k = 0; k < Annz; k++) Aj[k] -= cstart;
6660:   }

6662:   PetscCall(MatGetRootType_Private(mat, &rtype));

6664:   MatSeqXAIJGetOptions_Private(mpiaij->A);
6665:   PetscCall(MatDestroy(&mpiaij->A));
6666:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, Ai, Aj, Aa, &mpiaij->A));
6667:   PetscCall(MatSetBlockSizesFromMats(mpiaij->A, mat, mat));
6668:   MatSeqXAIJRestoreOptions_Private(mpiaij->A);

6670:   MatSeqXAIJGetOptions_Private(mpiaij->B);
6671:   PetscCall(MatDestroy(&mpiaij->B));
6672:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, mat->cmap->N, Bi, Bj, Ba, &mpiaij->B));
6673:   PetscCall(MatSetBlockSizesFromMats(mpiaij->B, mat, mat));
6674:   MatSeqXAIJRestoreOptions_Private(mpiaij->B);

6676:   PetscCall(MatSetUpMultiply_MPIAIJ(mat));
6677:   mat->was_assembled = PETSC_TRUE; // was_assembled in effect means the Mvctx is built; doing so avoids redundant MatSetUpMultiply_MPIAIJ
6678:   mat->nonzerostate  = mpiaij->A->nonzerostate + mpiaij->B->nonzerostate;
6679:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));

6681:   a          = (Mat_SeqAIJ *)mpiaij->A->data;
6682:   b          = (Mat_SeqAIJ *)mpiaij->B->data;
6683:   a->free_a  = PETSC_TRUE;
6684:   a->free_ij = PETSC_TRUE;
6685:   b->free_a  = PETSC_TRUE;
6686:   b->free_ij = PETSC_TRUE;
6687:   a->maxnz   = a->nz;
6688:   b->maxnz   = b->nz;

6690:   /* conversion must happen AFTER multiply setup */
6691:   PetscCall(MatConvert(mpiaij->A, rtype, MAT_INPLACE_MATRIX, &mpiaij->A));
6692:   PetscCall(MatConvert(mpiaij->B, rtype, MAT_INPLACE_MATRIX, &mpiaij->B));
6693:   PetscCall(VecDestroy(&mpiaij->lvec));
6694:   PetscCall(MatCreateVecs(mpiaij->B, &mpiaij->lvec, NULL));

6696:   // Put the COO struct in a container and then attach that to the matrix
6697:   PetscCall(PetscMalloc1(1, &coo));
6698:   coo->n       = coo_n;
6699:   coo->sf      = sf2;
6700:   coo->sendlen = nleaves;
6701:   coo->recvlen = nroots;
6702:   coo->Annz    = Annz;
6703:   coo->Bnnz    = Bnnz;
6704:   coo->Annz2   = Annz2;
6705:   coo->Bnnz2   = Bnnz2;
6706:   coo->Atot1   = Atot1;
6707:   coo->Atot2   = Atot2;
6708:   coo->Btot1   = Btot1;
6709:   coo->Btot2   = Btot2;
6710:   coo->Ajmap1  = Ajmap1;
6711:   coo->Aperm1  = Aperm1;
6712:   coo->Bjmap1  = Bjmap1;
6713:   coo->Bperm1  = Bperm1;
6714:   coo->Aimap2  = Aimap2;
6715:   coo->Ajmap2  = Ajmap2;
6716:   coo->Aperm2  = Aperm2;
6717:   coo->Bimap2  = Bimap2;
6718:   coo->Bjmap2  = Bjmap2;
6719:   coo->Bperm2  = Bperm2;
6720:   coo->Cperm1  = Cperm1;
6721:   // Allocate in preallocation. If not used, it has zero cost on host
6722:   PetscCall(PetscMalloc2(coo->sendlen, &coo->sendbuf, coo->recvlen, &coo->recvbuf));
6723:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
6724:   PetscCall(PetscContainerSetPointer(container, coo));
6725:   PetscCall(PetscContainerSetCtxDestroy(container, MatCOOStructDestroy_MPIAIJ));
6726:   PetscCall(PetscObjectCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject)container));
6727:   PetscCall(PetscContainerDestroy(&container));
6728:   PetscFunctionReturn(PETSC_SUCCESS);
6729: }

6731: static PetscErrorCode MatSetValuesCOO_MPIAIJ(Mat mat, const PetscScalar v[], InsertMode imode)
6732: {
6733:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6734:   Mat                  A = mpiaij->A, B = mpiaij->B;
6735:   PetscScalar         *Aa, *Ba;
6736:   PetscScalar         *sendbuf, *recvbuf;
6737:   const PetscCount    *Ajmap1, *Ajmap2, *Aimap2;
6738:   const PetscCount    *Bjmap1, *Bjmap2, *Bimap2;
6739:   const PetscCount    *Aperm1, *Aperm2, *Bperm1, *Bperm2;
6740:   const PetscCount    *Cperm1;
6741:   PetscContainer       container;
6742:   MatCOOStruct_MPIAIJ *coo;

6744:   PetscFunctionBegin;
6745:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container));
6746:   PetscCheck(container, PetscObjectComm((PetscObject)mat), PETSC_ERR_PLIB, "Not found MatCOOStruct on this matrix");
6747:   PetscCall(PetscContainerGetPointer(container, &coo));
6748:   sendbuf = coo->sendbuf;
6749:   recvbuf = coo->recvbuf;
6750:   Ajmap1  = coo->Ajmap1;
6751:   Ajmap2  = coo->Ajmap2;
6752:   Aimap2  = coo->Aimap2;
6753:   Bjmap1  = coo->Bjmap1;
6754:   Bjmap2  = coo->Bjmap2;
6755:   Bimap2  = coo->Bimap2;
6756:   Aperm1  = coo->Aperm1;
6757:   Aperm2  = coo->Aperm2;
6758:   Bperm1  = coo->Bperm1;
6759:   Bperm2  = coo->Bperm2;
6760:   Cperm1  = coo->Cperm1;

6762:   PetscCall(MatSeqAIJGetArray(A, &Aa)); /* Might read and write matrix values */
6763:   PetscCall(MatSeqAIJGetArray(B, &Ba));

6765:   /* Pack entries to be sent to remote */
6766:   for (PetscCount i = 0; i < coo->sendlen; i++) sendbuf[i] = v[Cperm1[i]];

6768:   /* Send remote entries to their owner and overlap the communication with local computation */
6769:   PetscCall(PetscSFReduceWithMemTypeBegin(coo->sf, MPIU_SCALAR, PETSC_MEMTYPE_HOST, sendbuf, PETSC_MEMTYPE_HOST, recvbuf, MPI_REPLACE));
6770:   /* Add local entries to A and B */
6771:   for (PetscCount i = 0; i < coo->Annz; i++) { /* All nonzeros in A are either zero'ed or added with a value (i.e., initialized) */
6772:     PetscScalar sum = 0.0;                     /* Do partial summation first to improve numerical stability */
6773:     for (PetscCount k = Ajmap1[i]; k < Ajmap1[i + 1]; k++) sum += v[Aperm1[k]];
6774:     Aa[i] = (imode == INSERT_VALUES ? 0.0 : Aa[i]) + sum;
6775:   }
6776:   for (PetscCount i = 0; i < coo->Bnnz; i++) {
6777:     PetscScalar sum = 0.0;
6778:     for (PetscCount k = Bjmap1[i]; k < Bjmap1[i + 1]; k++) sum += v[Bperm1[k]];
6779:     Ba[i] = (imode == INSERT_VALUES ? 0.0 : Ba[i]) + sum;
6780:   }
6781:   PetscCall(PetscSFReduceEnd(coo->sf, MPIU_SCALAR, sendbuf, recvbuf, MPI_REPLACE));

6783:   /* Add received remote entries to A and B */
6784:   for (PetscCount i = 0; i < coo->Annz2; i++) {
6785:     for (PetscCount k = Ajmap2[i]; k < Ajmap2[i + 1]; k++) Aa[Aimap2[i]] += recvbuf[Aperm2[k]];
6786:   }
6787:   for (PetscCount i = 0; i < coo->Bnnz2; i++) {
6788:     for (PetscCount k = Bjmap2[i]; k < Bjmap2[i + 1]; k++) Ba[Bimap2[i]] += recvbuf[Bperm2[k]];
6789:   }
6790:   PetscCall(MatSeqAIJRestoreArray(A, &Aa));
6791:   PetscCall(MatSeqAIJRestoreArray(B, &Ba));
6792:   PetscFunctionReturn(PETSC_SUCCESS);
6793: }

6795: /*MC
6796:    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.

6798:    Options Database Keys:
6799: . -mat_type mpiaij - sets the matrix type to `MATMPIAIJ` during a call to `MatSetFromOptions()`

6801:    Level: beginner

6803:    Notes:
6804:    `MatSetValues()` may be called for this matrix type with a `NULL` argument for the numerical values,
6805:     in this case the values associated with the rows and columns one passes in are set to zero
6806:     in the matrix

6808:     `MatSetOptions`(,`MAT_STRUCTURE_ONLY`,`PETSC_TRUE`) may be called for this matrix type. In this no
6809:     space is allocated for the nonzero entries and any entries passed with `MatSetValues()` are ignored

6811: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJ`, `MATAIJ`, `MatCreateAIJ()`
6812: M*/
6813: PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
6814: {
6815:   Mat_MPIAIJ *b;
6816:   PetscMPIInt size;

6818:   PetscFunctionBegin;
6819:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

6821:   PetscCall(PetscNew(&b));
6822:   B->data       = (void *)b;
6823:   B->ops[0]     = MatOps_Values;
6824:   B->assembled  = PETSC_FALSE;
6825:   B->insertmode = NOT_SET_VALUES;
6826:   b->size       = size;

6828:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)B), &b->rank));

6830:   /* build cache for off array entries formed */
6831:   PetscCall(MatStashCreate_Private(PetscObjectComm((PetscObject)B), 1, &B->stash));

6833:   b->donotstash  = PETSC_FALSE;
6834:   b->colmap      = NULL;
6835:   b->garray      = NULL;
6836:   b->roworiented = PETSC_TRUE;

6838:   /* stuff used for matrix vector multiply */
6839:   b->lvec  = NULL;
6840:   b->Mvctx = NULL;

6842:   /* stuff for MatGetRow() */
6843:   b->rowindices   = NULL;
6844:   b->rowvalues    = NULL;
6845:   b->getrowactive = PETSC_FALSE;

6847:   /* flexible pointer used in CUSPARSE classes */
6848:   b->spptr = NULL;

6850:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetUseScalableIncreaseOverlap_C", MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ));
6851:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatStoreValues_C", MatStoreValues_MPIAIJ));
6852:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatRetrieveValues_C", MatRetrieveValues_MPIAIJ));
6853:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatIsTranspose_C", MatIsTranspose_MPIAIJ));
6854:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocation_C", MatMPIAIJSetPreallocation_MPIAIJ));
6855:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetPreallocation_C", MatResetPreallocation_MPIAIJ));
6856:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetHash_C", MatResetHash_MPIAIJ));
6857:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocationCSR_C", MatMPIAIJSetPreallocationCSR_MPIAIJ));
6858:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatDiagonalScaleLocal_C", MatDiagonalScaleLocal_MPIAIJ));
6859:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijperm_C", MatConvert_MPIAIJ_MPIAIJPERM));
6860:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijsell_C", MatConvert_MPIAIJ_MPIAIJSELL));
6861: #if PetscDefined(HAVE_CUDA)
6862:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcusparse_C", MatConvert_MPIAIJ_MPIAIJCUSPARSE));
6863: #endif
6864: #if PetscDefined(HAVE_HIP)
6865:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijhipsparse_C", MatConvert_MPIAIJ_MPIAIJHIPSPARSE));
6866: #endif
6867: #if PetscDefined(HAVE_KOKKOS_KERNELS)
6868:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijkokkos_C", MatConvert_MPIAIJ_MPIAIJKokkos));
6869: #endif
6870: #if PetscDefined(HAVE_MKL_SPARSE)
6871:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijmkl_C", MatConvert_MPIAIJ_MPIAIJMKL));
6872: #endif
6873:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcrl_C", MatConvert_MPIAIJ_MPIAIJCRL));
6874:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpibaij_C", MatConvert_MPIAIJ_MPIBAIJ));
6875:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisbaij_C", MatConvert_MPIAIJ_MPISBAIJ));
6876:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpidense_C", MatConvert_MPIAIJ_MPIDense));
6877: #if PetscDefined(HAVE_ELEMENTAL)
6878:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_elemental_C", MatConvert_MPIAIJ_Elemental));
6879: #endif
6880: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
6881:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_scalapack_C", MatConvert_AIJ_ScaLAPACK));
6882: #endif
6883:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_is_C", MatConvert_XAIJ_IS));
6884:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisell_C", MatConvert_MPIAIJ_MPISELL));
6885: #if PetscDefined(HAVE_HYPRE)
6886:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_hypre_C", MatConvert_AIJ_HYPRE));
6887:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", MatProductSetFromOptions_Transpose_AIJ_AIJ));
6888: #endif
6889:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_is_mpiaij_C", MatProductSetFromOptions_IS_XAIJ));
6890:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_mpiaij_mpiaij_C", MatProductSetFromOptions_MPIAIJ));
6891:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_MPIAIJ));
6892:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetValuesCOO_C", MatSetValuesCOO_MPIAIJ));
6893:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatGetMultPetscSF_C", MatGetMultPetscSF_MPIAIJ));
6894:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATMPIAIJ));
6895:   PetscFunctionReturn(PETSC_SUCCESS);
6896: }

6898: /*@
6899:   MatCreateMPIAIJWithSplitArrays - creates a `MATMPIAIJ` matrix using arrays that contain the "diagonal"
6900:   and "off-diagonal" part of the matrix in CSR format.

6902:   Collective

6904:   Input Parameters:
6905: + comm - MPI communicator
6906: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
6907: . n    - This value should be the same as the local size used in creating the
6908:          x vector for the matrix-vector product $y = Ax$. (or `PETSC_DECIDE` to have
6909:          calculated if `N` is given) For square matrices `n` is almost always `m`.
6910: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
6911: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
6912: . 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
6913: . j    - column indices, which must be local, i.e., based off the start column of the diagonal portion
6914: . a    - matrix values
6915: . 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
6916: . oj   - column indices, which must be global, representing global columns in the `MATMPIAIJ` matrix
6917: - oa   - matrix values

6919:   Output Parameter:
6920: . mat - the matrix

6922:   Level: advanced

6924:   Notes:
6925:   The `i`, `j`, and `a` arrays ARE NOT copied by this routine into the internal format used by PETSc (even in Fortran). The user
6926:   must free the arrays once the matrix has been destroyed and not before.

6928:   The `i` and `j` indices are 0 based

6930:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix

6932:   This sets local rows and cannot be used to set off-processor values.

6934:   Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
6935:   legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
6936:   not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
6937:   the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
6938:   keep track of the underlying array. Use `MatSetOption`(A,`MAT_NO_OFF_PROC_ENTRIES`,`PETSC_TRUE`) to disable all
6939:   communication if it is known that only local entries will be set.

6941: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
6942:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithArrays()`
6943: @*/
6944: 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)
6945: {
6946:   Mat_MPIAIJ *maij;

6948:   PetscFunctionBegin;
6949:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
6950:   PetscCheck(i[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
6951:   PetscCheck(oi[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "oi (row indices) must start with 0");
6952:   PetscCall(MatCreate(comm, mat));
6953:   PetscCall(MatSetSizes(*mat, m, n, M, N));
6954:   PetscCall(MatSetType(*mat, MATMPIAIJ));
6955:   maij = (Mat_MPIAIJ *)(*mat)->data;

6957:   (*mat)->preallocated = PETSC_TRUE;

6959:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
6960:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

6962:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, i, j, a, &maij->A));
6963:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, (*mat)->cmap->N, oi, oj, oa, &maij->B));

6965:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
6966:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
6967:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
6968:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
6969:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
6970:   PetscFunctionReturn(PETSC_SUCCESS);
6971: }

6973: typedef struct {
6974:   Mat       *mp;    /* intermediate products */
6975:   PetscBool *mptmp; /* is the intermediate product temporary ? */
6976:   PetscInt   cp;    /* number of intermediate products */

6978:   /* support for MatGetBrowsOfAoCols_MPIAIJ for P_oth */
6979:   PetscInt    *startsj_s, *startsj_r;
6980:   PetscScalar *bufa;
6981:   Mat          P_oth;

6983:   /* may take advantage of merging product->B */
6984:   Mat Bloc; /* B-local by merging diag and off-diag */

6986:   /* cusparse does not have support to split between symbolic and numeric phases.
6987:      When api_user is true, we don't need to update the numerical values
6988:      of the temporary storage */
6989:   PetscBool reusesym;

6991:   /* support for COO values insertion */
6992:   PetscScalar *coo_v, *coo_w; /* store on-process and off-process COO scalars, and used as MPI recv/send buffers respectively */
6993:   PetscInt   **own;           /* own[i] points to address of on-process COO indices for Mat mp[i] */
6994:   PetscInt   **off;           /* off[i] points to address of off-process COO indices for Mat mp[i] */
6995:   PetscBool    hasoffproc;    /* if true, have off-process values insertion (i.e. AtB or PtAP) */
6996:   PetscSF      sf;            /* used for non-local values insertion and memory malloc */
6997:   PetscMemType mtype;

6999:   /* customization */
7000:   PetscBool abmerge;
7001:   PetscBool P_oth_bind;
7002: } MatMatMPIAIJBACKEND;

7004: static PetscErrorCode MatProductCtxDestroy_MatMatMPIAIJBACKEND(PetscCtxRt data)
7005: {
7006:   MatMatMPIAIJBACKEND *mmdata = *(MatMatMPIAIJBACKEND **)data;
7007:   PetscInt             i;

7009:   PetscFunctionBegin;
7010:   PetscCall(PetscFree2(mmdata->startsj_s, mmdata->startsj_r));
7011:   PetscCall(PetscFree(mmdata->bufa));
7012:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_v));
7013:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_w));
7014:   PetscCall(MatDestroy(&mmdata->P_oth));
7015:   PetscCall(MatDestroy(&mmdata->Bloc));
7016:   PetscCall(PetscSFDestroy(&mmdata->sf));
7017:   for (i = 0; i < mmdata->cp; i++) PetscCall(MatDestroy(&mmdata->mp[i]));
7018:   PetscCall(PetscFree2(mmdata->mp, mmdata->mptmp));
7019:   PetscCall(PetscFree(mmdata->own[0]));
7020:   PetscCall(PetscFree(mmdata->own));
7021:   PetscCall(PetscFree(mmdata->off[0]));
7022:   PetscCall(PetscFree(mmdata->off));
7023:   PetscCall(PetscFree(mmdata));
7024:   PetscFunctionReturn(PETSC_SUCCESS);
7025: }

7027: /* Copy selected n entries with indices in idx[] of A to v[].
7028:    If idx is NULL, copy the whole data array of A to v[]
7029:  */
7030: static PetscErrorCode MatSeqAIJCopySubArray(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
7031: {
7032:   PetscErrorCode (*f)(Mat, PetscInt, const PetscInt[], PetscScalar[]);

7034:   PetscFunctionBegin;
7035:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", &f));
7036:   if (f) PetscCall((*f)(A, n, idx, v));
7037:   else {
7038:     const PetscScalar *vv;

7040:     PetscCall(MatSeqAIJGetArrayRead(A, &vv));
7041:     if (n && idx) {
7042:       PetscScalar    *w  = v;
7043:       const PetscInt *oi = idx;

7045:       for (PetscInt j = 0; j < n; j++) *w++ = vv[*oi++];
7046:     } else {
7047:       PetscCall(PetscArraycpy(v, vv, n));
7048:     }
7049:     PetscCall(MatSeqAIJRestoreArrayRead(A, &vv));
7050:   }
7051:   PetscFunctionReturn(PETSC_SUCCESS);
7052: }

7054: static PetscErrorCode MatProductNumeric_MPIAIJBACKEND(Mat C)
7055: {
7056:   MatMatMPIAIJBACKEND *mmdata;
7057:   PetscInt             i, n_d, n_o;

7059:   PetscFunctionBegin;
7060:   MatCheckProduct(C, 1);
7061:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data empty");
7062:   mmdata = (MatMatMPIAIJBACKEND *)C->product->data;
7063:   if (!mmdata->reusesym) { /* update temporary matrices */
7064:     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));
7065:     if (mmdata->Bloc) PetscCall(MatMPIAIJGetLocalMatMerge(C->product->B, MAT_REUSE_MATRIX, NULL, &mmdata->Bloc));
7066:   }
7067:   mmdata->reusesym = PETSC_FALSE;

7069:   for (i = 0; i < mmdata->cp; i++) {
7070:     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]);
7071:     PetscCall((*mmdata->mp[i]->ops->productnumeric)(mmdata->mp[i]));
7072:   }
7073:   for (i = 0, n_d = 0, n_o = 0; i < mmdata->cp; i++) {
7074:     PetscInt noff;

7076:     PetscCall(PetscIntCast(mmdata->off[i + 1] - mmdata->off[i], &noff));
7077:     if (mmdata->mptmp[i]) continue;
7078:     if (noff) {
7079:       PetscInt nown;

7081:       PetscCall(PetscIntCast(mmdata->own[i + 1] - mmdata->own[i], &nown));
7082:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], noff, mmdata->off[i], mmdata->coo_w + n_o));
7083:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], nown, mmdata->own[i], mmdata->coo_v + n_d));
7084:       n_o += noff;
7085:       n_d += nown;
7086:     } else {
7087:       Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mmdata->mp[i]->data;

7089:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], mm->nz, NULL, mmdata->coo_v + n_d));
7090:       n_d += mm->nz;
7091:     }
7092:   }
7093:   if (mmdata->hasoffproc) { /* offprocess insertion */
7094:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7095:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7096:   }
7097:   PetscCall(MatSetValuesCOO(C, mmdata->coo_v, INSERT_VALUES));
7098:   PetscFunctionReturn(PETSC_SUCCESS);
7099: }

7101: /* Support for Pt * A, A * P, or Pt * A * P */
7102: #define MAX_NUMBER_INTERMEDIATE 4
7103: PetscErrorCode MatProductSymbolic_MPIAIJBACKEND(Mat C)
7104: {
7105:   Mat_Product           *product = C->product;
7106:   Mat                    A, P, mp[MAX_NUMBER_INTERMEDIATE]; /* A, P and a series of intermediate matrices */
7107:   Mat_MPIAIJ            *a, *p;
7108:   MatMatMPIAIJBACKEND   *mmdata;
7109:   ISLocalToGlobalMapping P_oth_l2g = NULL;
7110:   IS                     glob      = NULL;
7111:   const char            *prefix;
7112:   char                   pprefix[256];
7113:   const PetscInt        *globidx, *P_oth_idx;
7114:   PetscInt               i, j, cp, m, n, M, N, *coo_i, *coo_j;
7115:   PetscCount             ncoo, ncoo_d, ncoo_o, ncoo_oown;
7116:   PetscInt               cmapt[MAX_NUMBER_INTERMEDIATE], rmapt[MAX_NUMBER_INTERMEDIATE]; /* col/row map type for each Mat in mp[]. */
7117:                                                                                          /* type-0: consecutive, start from 0; type-1: consecutive with */
7118:                                                                                          /* a base offset; type-2: sparse with a local to global map table */
7119:   const PetscInt *cmapa[MAX_NUMBER_INTERMEDIATE], *rmapa[MAX_NUMBER_INTERMEDIATE];       /* col/row local to global map array (table) for type-2 map type */

7121:   MatProductType ptype;
7122:   PetscBool      mptmp[MAX_NUMBER_INTERMEDIATE], hasoffproc = PETSC_FALSE, iscuda, iship, iskokk;
7123:   PetscMPIInt    size;

7125:   PetscFunctionBegin;
7126:   MatCheckProduct(C, 1);
7127:   PetscCheck(!product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
7128:   ptype = product->type;
7129:   if (product->A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
7130:     ptype                                          = MATPRODUCT_AB;
7131:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
7132:   }
7133:   switch (ptype) {
7134:   case MATPRODUCT_AB:
7135:     A          = product->A;
7136:     P          = product->B;
7137:     m          = A->rmap->n;
7138:     n          = P->cmap->n;
7139:     M          = A->rmap->N;
7140:     N          = P->cmap->N;
7141:     hasoffproc = PETSC_FALSE; /* will not scatter mat product values to other processes */
7142:     break;
7143:   case MATPRODUCT_AtB:
7144:     P          = product->A;
7145:     A          = product->B;
7146:     m          = P->cmap->n;
7147:     n          = A->cmap->n;
7148:     M          = P->cmap->N;
7149:     N          = A->cmap->N;
7150:     hasoffproc = PETSC_TRUE;
7151:     break;
7152:   case MATPRODUCT_PtAP:
7153:     A          = product->A;
7154:     P          = product->B;
7155:     m          = P->cmap->n;
7156:     n          = P->cmap->n;
7157:     M          = P->cmap->N;
7158:     N          = P->cmap->N;
7159:     hasoffproc = PETSC_TRUE;
7160:     break;
7161:   default:
7162:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7163:   }
7164:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)C), &size));
7165:   if (size == 1) hasoffproc = PETSC_FALSE;

7167:   /* defaults */
7168:   for (i = 0; i < MAX_NUMBER_INTERMEDIATE; i++) {
7169:     mp[i]    = NULL;
7170:     mptmp[i] = PETSC_FALSE;
7171:     rmapt[i] = -1;
7172:     cmapt[i] = -1;
7173:     rmapa[i] = NULL;
7174:     cmapa[i] = NULL;
7175:   }

7177:   /* customization */
7178:   PetscCall(PetscNew(&mmdata));
7179:   mmdata->reusesym = product->api_user;
7180:   if (ptype == MATPRODUCT_AB) {
7181:     if (product->api_user) {
7182:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
7183:       PetscCall(PetscOptionsBool("-matmatmult_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7184:       PetscCall(PetscOptionsBool("-matmatmult_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7185:       PetscOptionsEnd();
7186:     } else {
7187:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
7188:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7189:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7190:       PetscOptionsEnd();
7191:     }
7192:   } else if (ptype == MATPRODUCT_PtAP) {
7193:     if (product->api_user) {
7194:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
7195:       PetscCall(PetscOptionsBool("-matptap_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7196:       PetscOptionsEnd();
7197:     } else {
7198:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
7199:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7200:       PetscOptionsEnd();
7201:     }
7202:   }
7203:   a = (Mat_MPIAIJ *)A->data;
7204:   p = (Mat_MPIAIJ *)P->data;
7205:   PetscCall(MatSetSizes(C, m, n, M, N));
7206:   PetscCall(PetscLayoutSetUp(C->rmap));
7207:   PetscCall(PetscLayoutSetUp(C->cmap));
7208:   PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
7209:   PetscCall(MatGetOptionsPrefix(C, &prefix));

7211:   cp = 0;
7212:   switch (ptype) {
7213:   case MATPRODUCT_AB: /* A * P */
7214:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));

7216:     /* A_diag * P_local (merged or not) */
7217:     if (mmdata->abmerge) { /* P's diagonal and off-diag blocks are merged to one matrix, then multiplied by A_diag */
7218:       /* P is product->B */
7219:       PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7220:       PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7221:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7222:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7223:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7224:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7225:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7226:       mp[cp]->product->api_user = product->api_user;
7227:       PetscCall(MatProductSetFromOptions(mp[cp]));
7228:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7229:       PetscCall(ISGetIndices(glob, &globidx));
7230:       rmapt[cp] = 1;
7231:       cmapt[cp] = 2;
7232:       cmapa[cp] = globidx;
7233:       mptmp[cp] = PETSC_FALSE;
7234:       cp++;
7235:     } else { /* A_diag * P_diag and A_diag * P_off */
7236:       PetscCall(MatProductCreate(a->A, p->A, NULL, &mp[cp]));
7237:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7238:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7239:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7240:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7241:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7242:       mp[cp]->product->api_user = product->api_user;
7243:       PetscCall(MatProductSetFromOptions(mp[cp]));
7244:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7245:       rmapt[cp] = 1;
7246:       cmapt[cp] = 1;
7247:       mptmp[cp] = PETSC_FALSE;
7248:       cp++;
7249:       PetscCall(MatProductCreate(a->A, p->B, NULL, &mp[cp]));
7250:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7251:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7252:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7253:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7254:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7255:       mp[cp]->product->api_user = product->api_user;
7256:       PetscCall(MatProductSetFromOptions(mp[cp]));
7257:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7258:       rmapt[cp] = 1;
7259:       cmapt[cp] = 2;
7260:       cmapa[cp] = p->garray;
7261:       mptmp[cp] = PETSC_FALSE;
7262:       cp++;
7263:     }

7265:     /* A_off * P_other */
7266:     if (mmdata->P_oth) {
7267:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g)); /* make P_oth use local col ids */
7268:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7269:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7270:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7271:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7272:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7273:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7274:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7275:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7276:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7277:       mp[cp]->product->api_user = product->api_user;
7278:       PetscCall(MatProductSetFromOptions(mp[cp]));
7279:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7280:       rmapt[cp] = 1;
7281:       cmapt[cp] = 2;
7282:       cmapa[cp] = P_oth_idx;
7283:       mptmp[cp] = PETSC_FALSE;
7284:       cp++;
7285:     }
7286:     break;

7288:   case MATPRODUCT_AtB: /* (P^t * A): P_diag * A_loc + P_off * A_loc */
7289:     /* A is product->B */
7290:     PetscCall(MatMPIAIJGetLocalMatMerge(A, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7291:     if (A == P) { /* when A==P, we can take advantage of the already merged mmdata->Bloc */
7292:       PetscCall(MatProductCreate(mmdata->Bloc, mmdata->Bloc, NULL, &mp[cp]));
7293:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7294:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7295:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7296:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7297:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7298:       mp[cp]->product->api_user = product->api_user;
7299:       PetscCall(MatProductSetFromOptions(mp[cp]));
7300:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7301:       PetscCall(ISGetIndices(glob, &globidx));
7302:       rmapt[cp] = 2;
7303:       rmapa[cp] = globidx;
7304:       cmapt[cp] = 2;
7305:       cmapa[cp] = globidx;
7306:       mptmp[cp] = PETSC_FALSE;
7307:       cp++;
7308:     } else {
7309:       PetscCall(MatProductCreate(p->A, mmdata->Bloc, NULL, &mp[cp]));
7310:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7311:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7312:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7313:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7314:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7315:       mp[cp]->product->api_user = product->api_user;
7316:       PetscCall(MatProductSetFromOptions(mp[cp]));
7317:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7318:       PetscCall(ISGetIndices(glob, &globidx));
7319:       rmapt[cp] = 1;
7320:       cmapt[cp] = 2;
7321:       cmapa[cp] = globidx;
7322:       mptmp[cp] = PETSC_FALSE;
7323:       cp++;
7324:       PetscCall(MatProductCreate(p->B, mmdata->Bloc, NULL, &mp[cp]));
7325:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7326:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7327:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7328:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7329:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7330:       mp[cp]->product->api_user = product->api_user;
7331:       PetscCall(MatProductSetFromOptions(mp[cp]));
7332:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7333:       rmapt[cp] = 2;
7334:       rmapa[cp] = p->garray;
7335:       cmapt[cp] = 2;
7336:       cmapa[cp] = globidx;
7337:       mptmp[cp] = PETSC_FALSE;
7338:       cp++;
7339:     }
7340:     break;
7341:   case MATPRODUCT_PtAP:
7342:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7343:     /* P is product->B */
7344:     PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7345:     PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7346:     PetscCall(MatProductSetType(mp[cp], MATPRODUCT_PtAP));
7347:     PetscCall(MatProductSetFill(mp[cp], product->fill));
7348:     PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7349:     PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7350:     PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7351:     mp[cp]->product->api_user = product->api_user;
7352:     PetscCall(MatProductSetFromOptions(mp[cp]));
7353:     PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7354:     PetscCall(ISGetIndices(glob, &globidx));
7355:     rmapt[cp] = 2;
7356:     rmapa[cp] = globidx;
7357:     cmapt[cp] = 2;
7358:     cmapa[cp] = globidx;
7359:     mptmp[cp] = PETSC_FALSE;
7360:     cp++;
7361:     if (mmdata->P_oth) {
7362:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g));
7363:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7364:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7365:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7366:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7367:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7368:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7369:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7370:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7371:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7372:       mp[cp]->product->api_user = product->api_user;
7373:       PetscCall(MatProductSetFromOptions(mp[cp]));
7374:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7375:       mptmp[cp] = PETSC_TRUE;
7376:       cp++;
7377:       PetscCall(MatProductCreate(mmdata->Bloc, mp[1], NULL, &mp[cp]));
7378:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7379:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7380:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7381:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7382:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7383:       mp[cp]->product->api_user = product->api_user;
7384:       PetscCall(MatProductSetFromOptions(mp[cp]));
7385:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7386:       rmapt[cp] = 2;
7387:       rmapa[cp] = globidx;
7388:       cmapt[cp] = 2;
7389:       cmapa[cp] = P_oth_idx;
7390:       mptmp[cp] = PETSC_FALSE;
7391:       cp++;
7392:     }
7393:     break;
7394:   default:
7395:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7396:   }
7397:   /* sanity check */
7398:   if (size > 1)
7399:     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);

7401:   PetscCall(PetscMalloc2(cp, &mmdata->mp, cp, &mmdata->mptmp));
7402:   for (i = 0; i < cp; i++) {
7403:     mmdata->mp[i]    = mp[i];
7404:     mmdata->mptmp[i] = mptmp[i];
7405:   }
7406:   mmdata->cp             = cp;
7407:   C->product->data       = mmdata;
7408:   C->product->destroy    = MatProductCtxDestroy_MatMatMPIAIJBACKEND;
7409:   C->ops->productnumeric = MatProductNumeric_MPIAIJBACKEND;

7411:   /* memory type */
7412:   mmdata->mtype = PETSC_MEMTYPE_HOST;
7413:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iscuda, MATSEQAIJCUSPARSE, MATMPIAIJCUSPARSE, ""));
7414:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iship, MATSEQAIJHIPSPARSE, MATMPIAIJHIPSPARSE, ""));
7415:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iskokk, MATSEQAIJKOKKOS, MATMPIAIJKOKKOS, ""));
7416:   if (iscuda) mmdata->mtype = PETSC_MEMTYPE_CUDA;
7417:   else if (iship) mmdata->mtype = PETSC_MEMTYPE_HIP;
7418:   else if (iskokk) mmdata->mtype = PETSC_MEMTYPE_KOKKOS;

7420:   /* prepare coo coordinates for values insertion */

7422:   /* count total nonzeros of those intermediate seqaij Mats
7423:     ncoo_d:    # of nonzeros of matrices that do not have offproc entries
7424:     ncoo_o:    # of nonzeros (of matrices that might have offproc entries) that will be inserted to remote procs
7425:     ncoo_oown: # of nonzeros (of matrices that might have offproc entries) that will be inserted locally
7426:   */
7427:   for (cp = 0, ncoo_d = 0, ncoo_o = 0, ncoo_oown = 0; cp < mmdata->cp; cp++) {
7428:     Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mp[cp]->data;
7429:     if (mptmp[cp]) continue;
7430:     if (rmapt[cp] == 2 && hasoffproc) { /* the rows need to be scatter to all processes (might include self) */
7431:       const PetscInt *rmap = rmapa[cp];
7432:       const PetscInt  mr   = mp[cp]->rmap->n;
7433:       const PetscInt  rs   = C->rmap->rstart;
7434:       const PetscInt  re   = C->rmap->rend;
7435:       const PetscInt *ii   = mm->i;
7436:       for (i = 0; i < mr; i++) {
7437:         const PetscInt gr = rmap[i];
7438:         const PetscInt nz = ii[i + 1] - ii[i];
7439:         if (gr < rs || gr >= re) ncoo_o += nz; /* this row is offproc */
7440:         else ncoo_oown += nz;                  /* this row is local */
7441:       }
7442:     } else ncoo_d += mm->nz;
7443:   }

7445:   /*
7446:     ncoo: total number of nonzeros (including those inserted by remote procs) belonging to this proc

7448:     ncoo = ncoo_d + ncoo_oown + ncoo2, which ncoo2 is number of nonzeros inserted to me by other procs.

7450:     off[0] points to a big index array, which is shared by off[1,2,...]. Similarly, for own[0].

7452:     off[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert to others
7453:     own[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert locally
7454:     so, off[p+1]-off[p] is the number of nonzeros that mp[p] will send to others.

7456:     coo_i/j/v[]: [ncoo] row/col/val of nonzeros belonging to this proc.
7457:     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.
7458:   */
7459:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->off)); /* +1 to make a csr-like data structure */
7460:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->own));

7462:   /* gather (i,j) of nonzeros inserted by remote procs */
7463:   if (hasoffproc) {
7464:     PetscSF  msf;
7465:     PetscInt ncoo2, *coo_i2, *coo_j2;

7467:     PetscCall(PetscMalloc1(ncoo_o, &mmdata->off[0]));
7468:     PetscCall(PetscMalloc1(ncoo_oown, &mmdata->own[0]));
7469:     PetscCall(PetscMalloc2(ncoo_o, &coo_i, ncoo_o, &coo_j)); /* to collect (i,j) of entries to be sent to others */

7471:     for (cp = 0, ncoo_o = 0; cp < mmdata->cp; cp++) {
7472:       Mat_SeqAIJ *mm     = (Mat_SeqAIJ *)mp[cp]->data;
7473:       PetscInt   *idxoff = mmdata->off[cp];
7474:       PetscInt   *idxown = mmdata->own[cp];
7475:       if (!mptmp[cp] && rmapt[cp] == 2) { /* row map is sparse */
7476:         const PetscInt *rmap = rmapa[cp];
7477:         const PetscInt *cmap = cmapa[cp];
7478:         const PetscInt *ii   = mm->i;
7479:         PetscInt       *coi  = coo_i + ncoo_o;
7480:         PetscInt       *coj  = coo_j + ncoo_o;
7481:         const PetscInt  mr   = mp[cp]->rmap->n;
7482:         const PetscInt  rs   = C->rmap->rstart;
7483:         const PetscInt  re   = C->rmap->rend;
7484:         const PetscInt  cs   = C->cmap->rstart;
7485:         for (i = 0; i < mr; i++) {
7486:           const PetscInt *jj = mm->j + ii[i];
7487:           const PetscInt  gr = rmap[i];
7488:           const PetscInt  nz = ii[i + 1] - ii[i];
7489:           if (gr < rs || gr >= re) { /* this is an offproc row */
7490:             for (j = ii[i]; j < ii[i + 1]; j++) {
7491:               *coi++    = gr;
7492:               *idxoff++ = j;
7493:             }
7494:             if (!cmapt[cp]) { /* already global */
7495:               for (j = 0; j < nz; j++) *coj++ = jj[j];
7496:             } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7497:               for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7498:             } else { /* offdiag */
7499:               for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7500:             }
7501:             ncoo_o += nz;
7502:           } else { /* this is a local row */
7503:             for (j = ii[i]; j < ii[i + 1]; j++) *idxown++ = j;
7504:           }
7505:         }
7506:       }
7507:       mmdata->off[cp + 1] = idxoff;
7508:       mmdata->own[cp + 1] = idxown;
7509:     }

7511:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7512:     PetscInt incoo_o;
7513:     PetscCall(PetscIntCast(ncoo_o, &incoo_o));
7514:     PetscCall(PetscSFSetGraphLayout(mmdata->sf, C->rmap, incoo_o /*nleaves*/, NULL /*ilocal*/, PETSC_OWN_POINTER, coo_i));
7515:     PetscCall(PetscSFGetMultiSF(mmdata->sf, &msf));
7516:     PetscCall(PetscSFGetGraph(msf, &ncoo2 /*nroots*/, NULL, NULL, NULL));
7517:     ncoo = ncoo_d + ncoo_oown + ncoo2;
7518:     PetscCall(PetscMalloc2(ncoo, &coo_i2, ncoo, &coo_j2));
7519:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown)); /* put (i,j) of remote nonzeros at back */
7520:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown));
7521:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7522:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7523:     PetscCall(PetscFree2(coo_i, coo_j));
7524:     /* allocate MPI send buffer to collect nonzero values to be sent to remote procs */
7525:     PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo_o * sizeof(PetscScalar), (void **)&mmdata->coo_w));
7526:     coo_i = coo_i2;
7527:     coo_j = coo_j2;
7528:   } else { /* no offproc values insertion */
7529:     ncoo = ncoo_d;
7530:     PetscCall(PetscMalloc2(ncoo, &coo_i, ncoo, &coo_j));

7532:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7533:     PetscCall(PetscSFSetGraph(mmdata->sf, 0, 0, NULL, PETSC_OWN_POINTER, NULL, PETSC_OWN_POINTER));
7534:     PetscCall(PetscSFSetUp(mmdata->sf));
7535:   }
7536:   mmdata->hasoffproc = hasoffproc;

7538:   /* gather (i,j) of nonzeros inserted locally */
7539:   for (cp = 0, ncoo_d = 0; cp < mmdata->cp; cp++) {
7540:     Mat_SeqAIJ     *mm   = (Mat_SeqAIJ *)mp[cp]->data;
7541:     PetscInt       *coi  = coo_i + ncoo_d;
7542:     PetscInt       *coj  = coo_j + ncoo_d;
7543:     const PetscInt *jj   = mm->j;
7544:     const PetscInt *ii   = mm->i;
7545:     const PetscInt *cmap = cmapa[cp];
7546:     const PetscInt *rmap = rmapa[cp];
7547:     const PetscInt  mr   = mp[cp]->rmap->n;
7548:     const PetscInt  rs   = C->rmap->rstart;
7549:     const PetscInt  re   = C->rmap->rend;
7550:     const PetscInt  cs   = C->cmap->rstart;

7552:     if (mptmp[cp]) continue;
7553:     if (rmapt[cp] == 1) { /* consecutive rows */
7554:       /* fill coo_i */
7555:       for (i = 0; i < mr; i++) {
7556:         const PetscInt gr = i + rs;
7557:         for (j = ii[i]; j < ii[i + 1]; j++) coi[j] = gr;
7558:       }
7559:       /* fill coo_j */
7560:       if (!cmapt[cp]) { /* type-0, already global */
7561:         PetscCall(PetscArraycpy(coj, jj, mm->nz));
7562:       } else if (cmapt[cp] == 1) {                        /* type-1, local to global for consecutive columns of C */
7563:         for (j = 0; j < mm->nz; j++) coj[j] = jj[j] + cs; /* lid + col start */
7564:       } else {                                            /* type-2, local to global for sparse columns */
7565:         for (j = 0; j < mm->nz; j++) coj[j] = cmap[jj[j]];
7566:       }
7567:       ncoo_d += mm->nz;
7568:     } else if (rmapt[cp] == 2) { /* sparse rows */
7569:       for (i = 0; i < mr; i++) {
7570:         const PetscInt *jj = mm->j + ii[i];
7571:         const PetscInt  gr = rmap[i];
7572:         const PetscInt  nz = ii[i + 1] - ii[i];
7573:         if (gr >= rs && gr < re) { /* local rows */
7574:           for (j = ii[i]; j < ii[i + 1]; j++) *coi++ = gr;
7575:           if (!cmapt[cp]) { /* type-0, already global */
7576:             for (j = 0; j < nz; j++) *coj++ = jj[j];
7577:           } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7578:             for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7579:           } else { /* type-2, local to global for sparse columns */
7580:             for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7581:           }
7582:           ncoo_d += nz;
7583:         }
7584:       }
7585:     }
7586:   }
7587:   if (glob) PetscCall(ISRestoreIndices(glob, &globidx));
7588:   PetscCall(ISDestroy(&glob));
7589:   if (P_oth_l2g) PetscCall(ISLocalToGlobalMappingRestoreIndices(P_oth_l2g, &P_oth_idx));
7590:   PetscCall(ISLocalToGlobalMappingDestroy(&P_oth_l2g));
7591:   /* allocate an array to store all nonzeros (inserted locally or remotely) belonging to this proc */
7592:   PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo * sizeof(PetscScalar), (void **)&mmdata->coo_v));

7594:   /* set block sizes */
7595:   A = product->A;
7596:   P = product->B;
7597:   switch (ptype) {
7598:   case MATPRODUCT_PtAP:
7599:     PetscCall(MatSetBlockSizes(C, P->cmap->bs, P->cmap->bs));
7600:     break;
7601:   case MATPRODUCT_RARt:
7602:     PetscCall(MatSetBlockSizes(C, P->rmap->bs, P->rmap->bs));
7603:     break;
7604:   case MATPRODUCT_ABC:
7605:     PetscCall(MatSetBlockSizesFromMats(C, A, product->C));
7606:     break;
7607:   case MATPRODUCT_AB:
7608:     PetscCall(MatSetBlockSizesFromMats(C, A, P));
7609:     break;
7610:   case MATPRODUCT_AtB:
7611:     PetscCall(MatSetBlockSizes(C, A->cmap->bs, P->cmap->bs));
7612:     break;
7613:   case MATPRODUCT_ABt:
7614:     PetscCall(MatSetBlockSizes(C, A->rmap->bs, P->rmap->bs));
7615:     break;
7616:   default:
7617:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for ProductType %s", MatProductTypes[ptype]);
7618:   }

7620:   /* preallocate with COO data */
7621:   PetscCall(MatSetPreallocationCOO(C, ncoo, coo_i, coo_j));
7622:   PetscCall(PetscFree2(coo_i, coo_j));
7623:   PetscFunctionReturn(PETSC_SUCCESS);
7624: }

7626: PetscErrorCode MatProductSetFromOptions_MPIAIJBACKEND(Mat mat)
7627: {
7628:   Mat_Product *product = mat->product;
7629: #if PetscDefined(HAVE_DEVICE)
7630:   PetscBool match  = PETSC_FALSE;
7631:   PetscBool usecpu = PETSC_FALSE;
7632: #else
7633:   PetscBool match = PETSC_TRUE;
7634: #endif

7636:   PetscFunctionBegin;
7637:   MatCheckProduct(mat, 1);
7638: #if PetscDefined(HAVE_DEVICE)
7639:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, ((PetscObject)product->A)->type_name, &match));
7640:   if (match) { /* we can always fallback to the CPU if requested */
7641:     switch (product->type) {
7642:     case MATPRODUCT_AB:
7643:       if (product->api_user) {
7644:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
7645:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7646:         PetscOptionsEnd();
7647:       } else {
7648:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
7649:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7650:         PetscOptionsEnd();
7651:       }
7652:       break;
7653:     case MATPRODUCT_AtB:
7654:       if (product->api_user) {
7655:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
7656:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7657:         PetscOptionsEnd();
7658:       } else {
7659:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
7660:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7661:         PetscOptionsEnd();
7662:       }
7663:       break;
7664:     case MATPRODUCT_PtAP:
7665:       if (product->api_user) {
7666:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
7667:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7668:         PetscOptionsEnd();
7669:       } else {
7670:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
7671:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7672:         PetscOptionsEnd();
7673:       }
7674:       break;
7675:     default:
7676:       break;
7677:     }
7678:     match = (PetscBool)!usecpu;
7679:   }
7680: #endif
7681:   if (match) {
7682:     switch (product->type) {
7683:     case MATPRODUCT_AB:
7684:     case MATPRODUCT_AtB:
7685:     case MATPRODUCT_PtAP:
7686:       mat->ops->productsymbolic = MatProductSymbolic_MPIAIJBACKEND;
7687:       break;
7688:     default:
7689:       break;
7690:     }
7691:   }
7692:   /* fallback to MPIAIJ ops */
7693:   if (!mat->ops->productsymbolic) PetscCall(MatProductSetFromOptions_MPIAIJ(mat));
7694:   PetscFunctionReturn(PETSC_SUCCESS);
7695: }

7697: /*
7698:    Produces a set of block column indices of the matrix row, one for each block represented in the original row

7700:    n - the number of block indices in cc[]
7701:    cc - the block indices (must be large enough to contain the indices)
7702: */
7703: static inline PetscErrorCode MatCollapseRow(Mat Amat, PetscInt row, PetscInt bs, PetscInt *n, PetscInt *cc)
7704: {
7705:   PetscInt        cnt = -1, nidx, j;
7706:   const PetscInt *idx;

7708:   PetscFunctionBegin;
7709:   PetscCall(MatGetRow(Amat, row, &nidx, &idx, NULL));
7710:   if (nidx) {
7711:     cnt     = 0;
7712:     cc[cnt] = idx[0] / bs;
7713:     for (j = 1; j < nidx; j++) {
7714:       if (cc[cnt] < idx[j] / bs) cc[++cnt] = idx[j] / bs;
7715:     }
7716:   }
7717:   PetscCall(MatRestoreRow(Amat, row, &nidx, &idx, NULL));
7718:   *n = cnt + 1;
7719:   PetscFunctionReturn(PETSC_SUCCESS);
7720: }

7722: /*
7723:     Produces a set of block column indices of the matrix block row, one for each block represented in the original set of rows

7725:     ncollapsed - the number of block indices
7726:     collapsed - the block indices (must be large enough to contain the indices)
7727: */
7728: static inline PetscErrorCode MatCollapseRows(Mat Amat, PetscInt start, PetscInt bs, PetscInt *w0, PetscInt *w1, PetscInt *w2, PetscInt *ncollapsed, PetscInt **collapsed)
7729: {
7730:   PetscInt i, nprev, *cprev = w0, ncur = 0, *ccur = w1, *merged = w2, *cprevtmp;

7732:   PetscFunctionBegin;
7733:   PetscCall(MatCollapseRow(Amat, start, bs, &nprev, cprev));
7734:   for (i = start + 1; i < start + bs; i++) {
7735:     PetscCall(MatCollapseRow(Amat, i, bs, &ncur, ccur));
7736:     PetscCall(PetscMergeIntArray(nprev, cprev, ncur, ccur, &nprev, &merged));
7737:     cprevtmp = cprev;
7738:     cprev    = merged;
7739:     merged   = cprevtmp;
7740:   }
7741:   *ncollapsed = nprev;
7742:   if (collapsed) *collapsed = cprev;
7743:   PetscFunctionReturn(PETSC_SUCCESS);
7744: }

7746: PETSC_INTERN PetscErrorCode MatCreateGraph_Simple_AIJ(Mat Amat, PetscBool symmetrize, PetscBool scale, PetscReal filter, PetscInt index_size, PetscInt index[], Mat *a_Gmat)
7747: {
7748:   PetscInt  Istart, Iend, Ii, jj, kk, ncols, nloc, NN, MM, bs;
7749:   MPI_Comm  comm;
7750:   Mat       Gmat;
7751:   PetscBool ismpiaij, isseqaij;
7752:   Mat       a, b, c;
7753:   MatType   jtype;

7755:   PetscFunctionBegin;
7756:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
7757:   PetscCall(MatGetOwnershipRange(Amat, &Istart, &Iend));
7758:   PetscCall(MatGetSize(Amat, &MM, &NN));
7759:   PetscCall(MatGetBlockSize(Amat, &bs));
7760:   nloc = (Iend - Istart) / bs;

7762:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATSEQAIJ, &isseqaij));
7763:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATMPIAIJ, &ismpiaij));
7764:   PetscCheck(isseqaij || ismpiaij, comm, PETSC_ERR_USER, "Require (MPI)AIJ matrix type");

7766:   /* TODO GPU: these calls are potentially expensive if matrices are large and we want to use the GPU */
7767:   /* A solution consists in providing a new API, MatAIJGetCollapsedAIJ, and each class can provide a fast
7768:      implementation */
7769:   if (bs > 1) {
7770:     PetscCall(MatGetType(Amat, &jtype));
7771:     PetscCall(MatCreate(comm, &Gmat));
7772:     PetscCall(MatSetType(Gmat, jtype));
7773:     PetscCall(MatSetSizes(Gmat, nloc, nloc, PETSC_DETERMINE, PETSC_DETERMINE));
7774:     PetscCall(MatSetBlockSizes(Gmat, 1, 1));
7775:     if (isseqaij || ((Mat_MPIAIJ *)Amat->data)->garray) {
7776:       PetscInt  *d_nnz, *o_nnz;
7777:       MatScalar *aa, val, *AA;
7778:       PetscInt  *aj, *ai, *AJ, nc, nmax = 0;

7780:       if (isseqaij) {
7781:         a = Amat;
7782:         b = NULL;
7783:       } else {
7784:         Mat_MPIAIJ *d = (Mat_MPIAIJ *)Amat->data;
7785:         a             = d->A;
7786:         b             = d->B;
7787:       }
7788:       PetscCall(PetscInfo(Amat, "New bs>1 Graph. nloc=%" PetscInt_FMT "\n", nloc));
7789:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7790:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7791:         PetscInt       *nnz = (c == a) ? d_nnz : o_nnz;
7792:         const PetscInt *cols1, *cols2;

7794:         for (PetscInt brow = 0, nc1, nc2, ok = 1; brow < nloc * bs; brow += bs) { // block rows
7795:           PetscCall(MatGetRow(c, brow, &nc2, &cols2, NULL));
7796:           nnz[brow / bs] = nc2 / bs;
7797:           if (nc2 % bs) ok = 0;
7798:           if (nnz[brow / bs] > nmax) nmax = nnz[brow / bs];
7799:           for (PetscInt ii = 1; ii < bs; ii++) { // check for non-dense blocks
7800:             PetscCall(MatGetRow(c, brow + ii, &nc1, &cols1, NULL));
7801:             if (nc1 != nc2) ok = 0;
7802:             else {
7803:               for (PetscInt jj = 0; jj < nc1 && ok == 1; jj++) {
7804:                 if (cols1[jj] != cols2[jj]) ok = 0;
7805:                 if (cols1[jj] % bs != jj % bs) ok = 0;
7806:               }
7807:             }
7808:             PetscCall(MatRestoreRow(c, brow + ii, &nc1, &cols1, NULL));
7809:           }
7810:           PetscCall(MatRestoreRow(c, brow, &nc2, &cols2, NULL));
7811:           if (!ok) {
7812:             PetscCall(PetscFree2(d_nnz, o_nnz));
7813:             PetscCall(PetscInfo(Amat, "Found sparse blocks - revert to slow method\n"));
7814:             goto old_bs;
7815:           }
7816:         }
7817:       }
7818:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7819:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7820:       PetscCall(PetscFree2(d_nnz, o_nnz));
7821:       PetscCall(PetscMalloc2(nmax, &AA, nmax, &AJ));
7822:       // diag
7823:       for (PetscInt brow = 0, n, grow; brow < nloc * bs; brow += bs) { // block rows
7824:         Mat_SeqAIJ *aseq = (Mat_SeqAIJ *)a->data;

7826:         ai = aseq->i;
7827:         n  = ai[brow + 1] - ai[brow];
7828:         aj = aseq->j + ai[brow];
7829:         for (PetscInt k = 0; k < n; k += bs) {   // block columns
7830:           AJ[k / bs] = aj[k] / bs + Istart / bs; // diag starts at (Istart,Istart)
7831:           val        = 0;
7832:           if (index_size == 0) {
7833:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7834:               aa = aseq->a + ai[brow + ii] + k;
7835:               for (PetscInt jj = 0; jj < bs; jj++) {    // columns in block
7836:                 val += PetscAbs(PetscRealPart(aa[jj])); // a sort of norm
7837:               }
7838:             }
7839:           } else {                                            // use (index,index) value if provided
7840:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7841:               PetscInt ii = index[iii];
7842:               aa          = aseq->a + ai[brow + ii] + k;
7843:               for (PetscInt jjj = 0; jjj < index_size; jjj++) { // columns in block
7844:                 PetscInt jj = index[jjj];
7845:                 val += PetscAbs(PetscRealPart(aa[jj]));
7846:               }
7847:             }
7848:           }
7849:           PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7850:           AA[k / bs] = val;
7851:         }
7852:         grow = Istart / bs + brow / bs;
7853:         PetscCall(MatSetValues(Gmat, 1, &grow, n / bs, AJ, AA, ADD_VALUES));
7854:       }
7855:       // off-diag
7856:       if (ismpiaij) {
7857:         Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)Amat->data;
7858:         const PetscScalar *vals;
7859:         const PetscInt    *cols, *garray = aij->garray;

7861:         PetscCheck(garray, PETSC_COMM_SELF, PETSC_ERR_USER, "No garray ?");
7862:         for (PetscInt brow = 0, grow; brow < nloc * bs; brow += bs) { // block rows
7863:           PetscCall(MatGetRow(b, brow, &ncols, &cols, NULL));
7864:           for (PetscInt k = 0, cidx = 0; k < ncols; k += bs, cidx++) {
7865:             PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs >= nmax");
7866:             AA[k / bs] = 0;
7867:             AJ[cidx]   = garray[cols[k]] / bs;
7868:           }
7869:           nc = ncols / bs;
7870:           PetscCall(MatRestoreRow(b, brow, &ncols, &cols, NULL));
7871:           if (index_size == 0) {
7872:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7873:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7874:               for (PetscInt k = 0; k < ncols; k += bs) {
7875:                 for (PetscInt jj = 0; jj < bs; jj++) { // cols in block
7876:                   PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7877:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7878:                 }
7879:               }
7880:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7881:             }
7882:           } else {                                            // use (index,index) value if provided
7883:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7884:               PetscInt ii = index[iii];
7885:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7886:               for (PetscInt k = 0; k < ncols; k += bs) {
7887:                 for (PetscInt jjj = 0; jjj < index_size; jjj++) { // cols in block
7888:                   PetscInt jj = index[jjj];
7889:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7890:                 }
7891:               }
7892:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7893:             }
7894:           }
7895:           grow = Istart / bs + brow / bs;
7896:           PetscCall(MatSetValues(Gmat, 1, &grow, nc, AJ, AA, ADD_VALUES));
7897:         }
7898:       }
7899:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7900:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7901:       PetscCall(PetscFree2(AA, AJ));
7902:     } else {
7903:       const PetscScalar *vals;
7904:       const PetscInt    *idx;
7905:       PetscInt          *d_nnz, *o_nnz, *w0, *w1, *w2;
7906:     old_bs:
7907:       /*
7908:        Determine the preallocation needed for the scalar matrix derived from the vector matrix.
7909:        */
7910:       PetscCall(PetscInfo(Amat, "OLD bs>1 CreateGraph\n"));
7911:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7912:       if (isseqaij) {
7913:         PetscInt max_d_nnz;

7915:         /*
7916:          Determine exact preallocation count for (sequential) scalar matrix
7917:          */
7918:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Amat, &max_d_nnz));
7919:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7920:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7921:         for (Ii = 0, jj = 0; Ii < Iend; Ii += bs, jj++) PetscCall(MatCollapseRows(Amat, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7922:         PetscCall(PetscFree3(w0, w1, w2));
7923:       } else if (ismpiaij) {
7924:         Mat             Daij, Oaij;
7925:         const PetscInt *garray;
7926:         PetscInt        max_d_nnz;

7928:         PetscCall(MatMPIAIJGetSeqAIJ(Amat, &Daij, &Oaij, &garray));
7929:         /*
7930:          Determine exact preallocation count for diagonal block portion of scalar matrix
7931:          */
7932:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Daij, &max_d_nnz));
7933:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7934:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7935:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) PetscCall(MatCollapseRows(Daij, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7936:         PetscCall(PetscFree3(w0, w1, w2));
7937:         /*
7938:          Over estimate (usually grossly over), preallocation count for off-diagonal portion of scalar matrix
7939:          */
7940:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) {
7941:           o_nnz[jj] = 0;
7942:           for (kk = 0; kk < bs; kk++) { /* rows that get collapsed to a single row */
7943:             PetscCall(MatGetRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7944:             o_nnz[jj] += ncols;
7945:             PetscCall(MatRestoreRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7946:           }
7947:           if (o_nnz[jj] > (NN / bs - nloc)) o_nnz[jj] = NN / bs - nloc;
7948:         }
7949:       } else SETERRQ(comm, PETSC_ERR_USER, "Require AIJ matrix type");
7950:       /* get scalar copy (norms) of matrix */
7951:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7952:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7953:       PetscCall(PetscFree2(d_nnz, o_nnz));
7954:       for (Ii = Istart; Ii < Iend; Ii++) {
7955:         PetscInt dest_row = Ii / bs;

7957:         PetscCall(MatGetRow(Amat, Ii, &ncols, &idx, &vals));
7958:         for (jj = 0; jj < ncols; jj++) {
7959:           PetscInt    dest_col = idx[jj] / bs;
7960:           PetscScalar sv       = PetscAbs(PetscRealPart(vals[jj]));

7962:           PetscCall(MatSetValues(Gmat, 1, &dest_row, 1, &dest_col, &sv, ADD_VALUES));
7963:         }
7964:         PetscCall(MatRestoreRow(Amat, Ii, &ncols, &idx, &vals));
7965:       }
7966:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7967:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7968:     }
7969:   } else {
7970:     if (symmetrize || filter >= 0 || scale) PetscCall(MatDuplicate(Amat, MAT_COPY_VALUES, &Gmat));
7971:     else {
7972:       Gmat = Amat;
7973:       PetscCall(PetscObjectReference((PetscObject)Gmat));
7974:     }
7975:     if (isseqaij) {
7976:       a = Gmat;
7977:       b = NULL;
7978:     } else {
7979:       Mat_MPIAIJ *d = (Mat_MPIAIJ *)Gmat->data;
7980:       a             = d->A;
7981:       b             = d->B;
7982:     }
7983:     if (filter >= 0 || scale) {
7984:       /* take absolute value of each entry */
7985:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7986:         MatInfo      info;
7987:         PetscScalar *avals;

7989:         PetscCall(MatGetInfo(c, MAT_LOCAL, &info));
7990:         PetscCall(MatSeqAIJGetArray(c, &avals));
7991:         for (int jj = 0; jj < info.nz_used; jj++) avals[jj] = PetscAbsScalar(avals[jj]);
7992:         PetscCall(MatSeqAIJRestoreArray(c, &avals));
7993:       }
7994:     }
7995:   }
7996:   if (symmetrize) {
7997:     PetscBool isset, issym;

7999:     PetscCall(MatIsSymmetricKnown(Amat, &isset, &issym));
8000:     if (!isset || !issym) {
8001:       Mat matTrans;

8003:       PetscCall(MatTranspose(Gmat, MAT_INITIAL_MATRIX, &matTrans));
8004:       PetscCall(MatAXPY(Gmat, 1.0, matTrans, Gmat->structurally_symmetric == PETSC_BOOL3_TRUE ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN));
8005:       PetscCall(MatDestroy(&matTrans));
8006:     }
8007:     PetscCall(MatSetOption(Gmat, MAT_SYMMETRIC, PETSC_TRUE));
8008:   } else if (Amat != Gmat) PetscCall(MatPropagateSymmetryOptions(Amat, Gmat));
8009:   if (scale) {
8010:     /* scale c for all diagonal values = 1 or -1 */
8011:     Vec diag;

8013:     PetscCall(MatCreateVecs(Gmat, &diag, NULL));
8014:     PetscCall(MatGetDiagonal(Gmat, diag));
8015:     PetscCall(VecReciprocal(diag));
8016:     PetscCall(VecSqrtAbs(diag));
8017:     PetscCall(MatDiagonalScale(Gmat, diag, diag));
8018:     PetscCall(VecDestroy(&diag));
8019:   }
8020:   PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_graph_view"));
8021:   if (filter >= 0) {
8022:     PetscCall(MatFilter(Gmat, filter, PETSC_TRUE, PETSC_TRUE));
8023:     PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_filter_graph_view"));
8024:   }
8025:   *a_Gmat = Gmat;
8026:   PetscFunctionReturn(PETSC_SUCCESS);
8027: }

8029: PETSC_INTERN PetscErrorCode MatGetCurrentMemType_MPIAIJ(Mat A, PetscMemType *memtype)
8030: {
8031:   Mat_MPIAIJ  *mpiaij = (Mat_MPIAIJ *)A->data;
8032:   PetscMemType mD = PETSC_MEMTYPE_HOST, mO = PETSC_MEMTYPE_HOST;

8034:   PetscFunctionBegin;
8035:   if (mpiaij->A) PetscCall(MatGetCurrentMemType(mpiaij->A, &mD));
8036:   if (mpiaij->B) PetscCall(MatGetCurrentMemType(mpiaij->B, &mO));
8037:   *memtype = (mD == mO) ? mD : PETSC_MEMTYPE_HOST;
8038:   PetscFunctionReturn(PETSC_SUCCESS);
8039: }

8041: /*
8042:     Special version for direct calls from Fortran
8043: */

8045: /* Change these macros so can be used in void function */
8046: /* Identical to PetscCallVoid, except it assigns to *_ierr */
8047: #undef PetscCall
8048: #define PetscCall(...) \
8049:   do { \
8050:     PetscErrorCode ierr_msv_mpiaij = __VA_ARGS__; \
8051:     if (PetscUnlikely(ierr_msv_mpiaij)) { \
8052:       *_ierr = PetscError(PETSC_COMM_SELF, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr_msv_mpiaij, PETSC_ERROR_REPEAT, " "); \
8053:       return; \
8054:     } \
8055:   } while (0)

8057: #undef SETERRQ
8058: #define SETERRQ(comm, ierr, ...) \
8059:   do { \
8060:     *_ierr = PetscError(comm, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr, PETSC_ERROR_INITIAL, __VA_ARGS__); \
8061:     return; \
8062:   } while (0)

8064: #if PetscDefined(HAVE_FORTRAN_CAPS)
8065:   #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
8066: #elif !PetscDefined(HAVE_FORTRAN_UNDERSCORE)
8067:   #define matsetvaluesmpiaij_ matsetvaluesmpiaij
8068: #else
8069: #endif
8070: PETSC_EXTERN void matsetvaluesmpiaij_(Mat *mmat, PetscInt *mm, const PetscInt im[], PetscInt *mn, const PetscInt in[], const PetscScalar v[], InsertMode *maddv, PetscErrorCode *_ierr)
8071: {
8072:   Mat         mat = *mmat;
8073:   PetscInt    m = *mm, n = *mn;
8074:   InsertMode  addv = *maddv;
8075:   Mat_MPIAIJ *aij  = (Mat_MPIAIJ *)mat->data;
8076:   PetscScalar value;

8078:   MatCheckPreallocated(mat, 1);
8079:   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
8080:   else PetscCheck(mat->insertmode == addv, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Cannot mix add values and insert values");
8081:   {
8082:     PetscInt  i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
8083:     PetscInt  cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
8084:     PetscBool roworiented = aij->roworiented;

8086:     /* Some Variables required in the macro */
8087:     Mat         A     = aij->A;
8088:     Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
8089:     PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
8090:     MatScalar  *aa;
8091:     PetscBool   ignorezeroentries = (a->ignorezeroentries && addv == ADD_VALUES) ? PETSC_TRUE : PETSC_FALSE;
8092:     Mat         B                 = aij->B;
8093:     Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
8094:     PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
8095:     MatScalar  *ba;
8096:     /* This variable below is only for the PETSC_HAVE_VIENNACL or PETSC_HAVE_CUDA cases, but we define it in all cases because we
8097:      * cannot use "#if defined" inside a macro. */
8098:     PETSC_UNUSED PetscBool inserted = PETSC_FALSE;

8100:     PetscInt  *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
8101:     PetscInt   nonew = a->nonew;
8102:     MatScalar *ap1, *ap2;

8104:     PetscFunctionBegin;
8105:     PetscCall(MatSeqAIJGetArray(A, &aa));
8106:     PetscCall(MatSeqAIJGetArray(B, &ba));
8107:     for (i = 0; i < m; i++) {
8108:       if (im[i] < 0) continue;
8109:       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);
8110:       if (im[i] >= rstart && im[i] < rend) {
8111:         row      = im[i] - rstart;
8112:         lastcol1 = -1;
8113:         rp1      = aj + ai[row];
8114:         ap1      = aa + ai[row];
8115:         rmax1    = aimax[row];
8116:         nrow1    = ailen[row];
8117:         low1     = 0;
8118:         high1    = nrow1;
8119:         lastcol2 = -1;
8120:         rp2      = bj + bi[row];
8121:         ap2      = ba + bi[row];
8122:         rmax2    = bimax[row];
8123:         nrow2    = bilen[row];
8124:         low2     = 0;
8125:         high2    = nrow2;

8127:         for (j = 0; j < n; j++) {
8128:           if (roworiented) value = v[i * n + j];
8129:           else value = v[i + j * m];
8130:           if (ignorezeroentries && value == 0.0 && addv == ADD_VALUES && im[i] != in[j]) continue;
8131:           if (in[j] >= cstart && in[j] < cend) {
8132:             col = in[j] - cstart;
8133:             MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
8134:           } else if (in[j] < 0) continue;
8135:           else if (PetscUnlikelyDebug(in[j] >= mat->cmap->N)) {
8136:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
8137:           } else {
8138:             if (mat->was_assembled) {
8139:               if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
8140: #if PetscDefined(USE_CTABLE)
8141:               PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col));
8142:               col--;
8143: #else
8144:               col = aij->colmap[in[j]] - 1;
8145: #endif
8146:               if (col < 0 && !((Mat_SeqAIJ *)aij->A->data)->nonew) {
8147:                 PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));
8148:                 col = in[j];
8149:                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
8150:                 B        = aij->B;
8151:                 b        = (Mat_SeqAIJ *)B->data;
8152:                 bimax    = b->imax;
8153:                 bi       = b->i;
8154:                 bilen    = b->ilen;
8155:                 bj       = b->j;
8156:                 rp2      = bj + bi[row];
8157:                 ap2      = ba + bi[row];
8158:                 rmax2    = bimax[row];
8159:                 nrow2    = bilen[row];
8160:                 low2     = 0;
8161:                 high2    = nrow2;
8162:                 bm       = aij->B->rmap->n;
8163:                 ba       = b->a;
8164:                 inserted = PETSC_FALSE;
8165:               }
8166:             } else col = in[j];
8167:             MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
8168:           }
8169:         }
8170:       } else if (!aij->donotstash) {
8171:         if (roworiented) {
8172:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, v + i * n, (PetscBool)(ignorezeroentries && addv == ADD_VALUES)));
8173:         } else {
8174:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, v + i, m, (PetscBool)(ignorezeroentries && addv == ADD_VALUES)));
8175:         }
8176:       }
8177:     }
8178:     PetscCall(MatSeqAIJRestoreArray(A, &aa));
8179:     PetscCall(MatSeqAIJRestoreArray(B, &ba));
8180:   }
8181:   PetscFunctionReturnVoid();
8182: }

8184: /* Undefining these here since they were redefined from their original definition above! No
8185:  * other PETSc functions should be defined past this point, as it is impossible to recover the
8186:  * original definitions */
8187: #undef PetscCall
8188: #undef SETERRQ