Actual source code: matmatmult.c

  1: /*
  2:   Defines matrix-matrix product routines for pairs of SeqAIJ matrices
  3:           C = A * B
  4: */

  6: #include <../src/mat/impls/aij/seq/aij.h>
  7: #include <../src/mat/utils/freespace.h>
  8: #include <petscbt.h>
  9: #include <petsc/private/isimpl.h>
 10: #include <../src/mat/impls/dense/seq/dense.h>

 12: PetscErrorCode MatMatMultNumeric_SeqAIJ_SeqAIJ(Mat A, Mat B, Mat C)
 13: {
 14:   PetscFunctionBegin;
 15:   if (C->ops->matmultnumeric) PetscCall((*C->ops->matmultnumeric)(A, B, C));
 16:   else PetscCall(MatMatMultNumeric_SeqAIJ_SeqAIJ_Sorted(A, B, C));
 17:   PetscFunctionReturn(PETSC_SUCCESS);
 18: }

 20: /* Modified from MatCreateSeqAIJWithArrays() */
 21: PETSC_INTERN PetscErrorCode MatSetSeqAIJWithArrays_private(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt i[], PetscInt j[], PetscScalar a[], MatType mtype, Mat mat)
 22: {
 23:   PetscInt    ii;
 24:   Mat_SeqAIJ *aij;
 25:   PetscBool   isseqaij, osingle, ofree_a, ofree_ij;

 27:   PetscFunctionBegin;
 28:   PetscCheck(m <= 0 || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
 29:   PetscCall(MatSetSizes(mat, m, n, m, n));

 31:   if (!mtype) {
 32:     PetscCall(PetscObjectBaseTypeCompare((PetscObject)mat, MATSEQAIJ, &isseqaij));
 33:     if (!isseqaij) PetscCall(MatSetType(mat, MATSEQAIJ));
 34:   } else {
 35:     PetscCall(MatSetType(mat, mtype));
 36:   }

 38:   aij      = (Mat_SeqAIJ *)(mat)->data;
 39:   osingle  = aij->singlemalloc;
 40:   ofree_a  = aij->free_a;
 41:   ofree_ij = aij->free_ij;
 42:   /* changes the free flags */
 43:   PetscCall(MatSeqAIJSetPreallocation_SeqAIJ(mat, MAT_SKIP_ALLOCATION, NULL));

 45:   PetscCall(PetscFree(aij->ilen));
 46:   PetscCall(PetscFree(aij->imax));
 47:   PetscCall(PetscMalloc1(m, &aij->imax));
 48:   PetscCall(PetscMalloc1(m, &aij->ilen));
 49:   for (ii = 0, aij->nonzerorowcnt = 0, aij->rmax = 0; ii < m; ii++) {
 50:     const PetscInt rnz = i[ii + 1] - i[ii];
 51:     aij->nonzerorowcnt += !!rnz;
 52:     aij->rmax     = PetscMax(aij->rmax, rnz);
 53:     aij->ilen[ii] = aij->imax[ii] = i[ii + 1] - i[ii];
 54:   }
 55:   aij->maxnz = i[m];
 56:   aij->nz    = i[m];

 58:   if (osingle) {
 59:     PetscCall(PetscFree3(aij->a, aij->j, aij->i));
 60:   } else {
 61:     if (ofree_a) PetscCall(PetscFree(aij->a));
 62:     if (ofree_ij) PetscCall(PetscFree(aij->j));
 63:     if (ofree_ij) PetscCall(PetscFree(aij->i));
 64:   }
 65:   aij->i     = i;
 66:   aij->j     = j;
 67:   aij->a     = a;
 68:   aij->nonew = -1; /* this indicates that inserting a new value in the matrix that generates a new nonzero is an error */
 69:   /* default to not retain ownership */
 70:   aij->singlemalloc = PETSC_FALSE;
 71:   aij->free_a       = PETSC_FALSE;
 72:   aij->free_ij      = PETSC_FALSE;
 73:   PetscCall(MatCheckCompressedRow(mat, aij->nonzerorowcnt, &aij->compressedrow, aij->i, m, 0.6));
 74:   // Always build the diag info when i, j are set
 75:   PetscCall(MatMarkDiagonal_SeqAIJ(mat));
 76:   PetscFunctionReturn(PETSC_SUCCESS);
 77: }

 79: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ(Mat A, Mat B, PetscReal fill, Mat C)
 80: {
 81:   Mat_Product        *product = C->product;
 82:   MatProductAlgorithm alg;
 83:   PetscBool           flg;

 85:   PetscFunctionBegin;
 86:   if (product) {
 87:     alg = product->alg;
 88:   } else {
 89:     alg = "sorted";
 90:   }
 91:   /* sorted */
 92:   PetscCall(PetscStrcmp(alg, "sorted", &flg));
 93:   if (flg) {
 94:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ_Sorted(A, B, fill, C));
 95:     PetscFunctionReturn(PETSC_SUCCESS);
 96:   }

 98:   /* scalable */
 99:   PetscCall(PetscStrcmp(alg, "scalable", &flg));
100:   if (flg) {
101:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ_Scalable(A, B, fill, C));
102:     PetscFunctionReturn(PETSC_SUCCESS);
103:   }

105:   /* scalable_fast */
106:   PetscCall(PetscStrcmp(alg, "scalable_fast", &flg));
107:   if (flg) {
108:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ_Scalable_fast(A, B, fill, C));
109:     PetscFunctionReturn(PETSC_SUCCESS);
110:   }

112:   /* heap */
113:   PetscCall(PetscStrcmp(alg, "heap", &flg));
114:   if (flg) {
115:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ_Heap(A, B, fill, C));
116:     PetscFunctionReturn(PETSC_SUCCESS);
117:   }

119:   /* btheap */
120:   PetscCall(PetscStrcmp(alg, "btheap", &flg));
121:   if (flg) {
122:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ_BTHeap(A, B, fill, C));
123:     PetscFunctionReturn(PETSC_SUCCESS);
124:   }

126:   /* llcondensed */
127:   PetscCall(PetscStrcmp(alg, "llcondensed", &flg));
128:   if (flg) {
129:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ_LLCondensed(A, B, fill, C));
130:     PetscFunctionReturn(PETSC_SUCCESS);
131:   }

133:   /* rowmerge */
134:   PetscCall(PetscStrcmp(alg, "rowmerge", &flg));
135:   if (flg) {
136:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ_RowMerge(A, B, fill, C));
137:     PetscFunctionReturn(PETSC_SUCCESS);
138:   }

140: #if defined(PETSC_HAVE_HYPRE)
141:   PetscCall(PetscStrcmp(alg, "hypre", &flg));
142:   if (flg) {
143:     PetscCall(MatMatMultSymbolic_AIJ_AIJ_wHYPRE(A, B, fill, C));
144:     PetscFunctionReturn(PETSC_SUCCESS);
145:   }
146: #endif

148:   SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "Mat Product Algorithm is not supported");
149: }

151: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ_LLCondensed(Mat A, Mat B, PetscReal fill, Mat C)
152: {
153:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c;
154:   PetscInt          *ai = a->i, *bi = b->i, *ci, *cj;
155:   PetscInt           am = A->rmap->N, bn = B->cmap->N, bm = B->rmap->N;
156:   PetscReal          afill;
157:   PetscInt           i, j, anzi, brow, bnzj, cnzi, *bj, *aj, *lnk, ndouble = 0, Crmax;
158:   PetscHMapI         ta;
159:   PetscBT            lnkbt;
160:   PetscFreeSpaceList free_space = NULL, current_space = NULL;

162:   PetscFunctionBegin;
163:   /* Get ci and cj */
164:   /* Allocate ci array, arrays for fill computation and */
165:   /* free space for accumulating nonzero column info */
166:   PetscCall(PetscMalloc1(am + 2, &ci));
167:   ci[0] = 0;

169:   /* create and initialize a linked list */
170:   PetscCall(PetscHMapICreateWithSize(bn, &ta));
171:   MatRowMergeMax_SeqAIJ(b, bm, ta);
172:   PetscCall(PetscHMapIGetSize(ta, &Crmax));
173:   PetscCall(PetscHMapIDestroy(&ta));

175:   PetscCall(PetscLLCondensedCreate(Crmax, bn, &lnk, &lnkbt));

177:   /* Initial FreeSpace size is fill*(nnz(A)+nnz(B)) */
178:   PetscCall(PetscFreeSpaceGet(PetscRealIntMultTruncate(fill, PetscIntSumTruncate(ai[am], bi[bm])), &free_space));

180:   current_space = free_space;

182:   /* Determine ci and cj */
183:   for (i = 0; i < am; i++) {
184:     anzi = ai[i + 1] - ai[i];
185:     aj   = a->j + ai[i];
186:     for (j = 0; j < anzi; j++) {
187:       brow = aj[j];
188:       bnzj = bi[brow + 1] - bi[brow];
189:       bj   = b->j + bi[brow];
190:       /* add non-zero cols of B into the sorted linked list lnk */
191:       PetscCall(PetscLLCondensedAddSorted(bnzj, bj, lnk, lnkbt));
192:     }
193:     /* add possible missing diagonal entry */
194:     if (C->force_diagonals) PetscCall(PetscLLCondensedAddSorted(1, &i, lnk, lnkbt));
195:     cnzi = lnk[0];

197:     /* If free space is not available, make more free space */
198:     /* Double the amount of total space in the list */
199:     if (current_space->local_remaining < cnzi) {
200:       PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(cnzi, current_space->total_array_size), &current_space));
201:       ndouble++;
202:     }

204:     /* Copy data into free space, then initialize lnk */
205:     PetscCall(PetscLLCondensedClean(bn, cnzi, current_space->array, lnk, lnkbt));

207:     current_space->array += cnzi;
208:     current_space->local_used += cnzi;
209:     current_space->local_remaining -= cnzi;

211:     ci[i + 1] = ci[i] + cnzi;
212:   }

214:   /* Column indices are in the list of free space */
215:   /* Allocate space for cj, initialize cj, and */
216:   /* destroy list of free space and other temporary array(s) */
217:   PetscCall(PetscMalloc1(ci[am] + 1, &cj));
218:   PetscCall(PetscFreeSpaceContiguous(&free_space, cj));
219:   PetscCall(PetscLLCondensedDestroy(lnk, lnkbt));

221:   /* put together the new symbolic matrix */
222:   PetscCall(MatSetSeqAIJWithArrays_private(PetscObjectComm((PetscObject)A), am, bn, ci, cj, NULL, ((PetscObject)A)->type_name, C));
223:   PetscCall(MatSetBlockSizesFromMats(C, A, B));

225:   /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
226:   /* These are PETSc arrays, so change flags so arrays can be deleted by PETSc */
227:   c          = (Mat_SeqAIJ *)C->data;
228:   c->free_a  = PETSC_FALSE;
229:   c->free_ij = PETSC_TRUE;
230:   c->nonew   = 0;

232:   /* fast, needs non-scalable O(bn) array 'abdense' */
233:   C->ops->matmultnumeric = MatMatMultNumeric_SeqAIJ_SeqAIJ_Sorted;

235:   /* set MatInfo */
236:   afill = (PetscReal)ci[am] / (ai[am] + bi[bm]) + 1.e-5;
237:   if (afill < 1.0) afill = 1.0;
238:   C->info.mallocs           = ndouble;
239:   C->info.fill_ratio_given  = fill;
240:   C->info.fill_ratio_needed = afill;

242: #if defined(PETSC_USE_INFO)
243:   if (ci[am]) {
244:     PetscCall(PetscInfo(C, "Reallocs %" PetscInt_FMT "; Fill ratio: given %g needed %g.\n", ndouble, (double)fill, (double)afill));
245:     PetscCall(PetscInfo(C, "Use MatMatMult(A,B,MatReuse,%g,&C) for best performance.;\n", (double)afill));
246:   } else {
247:     PetscCall(PetscInfo(C, "Empty matrix product\n"));
248:   }
249: #endif
250:   PetscFunctionReturn(PETSC_SUCCESS);
251: }

253: PetscErrorCode MatMatMultNumeric_SeqAIJ_SeqAIJ_Sorted(Mat A, Mat B, Mat C)
254: {
255:   PetscLogDouble     flops = 0.0;
256:   Mat_SeqAIJ        *a     = (Mat_SeqAIJ *)A->data;
257:   Mat_SeqAIJ        *b     = (Mat_SeqAIJ *)B->data;
258:   Mat_SeqAIJ        *c     = (Mat_SeqAIJ *)C->data;
259:   PetscInt          *ai = a->i, *aj = a->j, *bi = b->i, *bj = b->j, *bjj, *ci = c->i, *cj = c->j;
260:   PetscInt           am = A->rmap->n, cm = C->rmap->n;
261:   PetscInt           i, j, k, anzi, bnzi, cnzi, brow;
262:   PetscScalar       *ca, valtmp;
263:   PetscScalar       *ab_dense;
264:   PetscContainer     cab_dense;
265:   const PetscScalar *aa, *ba, *baj;

267:   PetscFunctionBegin;
268:   PetscCall(MatSeqAIJGetArrayRead(A, &aa));
269:   PetscCall(MatSeqAIJGetArrayRead(B, &ba));
270:   if (!c->a) { /* first call of MatMatMultNumeric_SeqAIJ_SeqAIJ, allocate ca and matmult_abdense */
271:     PetscCall(PetscMalloc1(ci[cm] + 1, &ca));
272:     c->a      = ca;
273:     c->free_a = PETSC_TRUE;
274:   } else ca = c->a;

276:   /* TODO this should be done in the symbolic phase */
277:   /* However, this function is so heavily used (sometimes in an hidden way through multnumeric function pointers
278:      that is hard to eradicate) */
279:   PetscCall(PetscObjectQuery((PetscObject)C, "__PETSc__ab_dense", (PetscObject *)&cab_dense));
280:   if (!cab_dense) {
281:     PetscCall(PetscMalloc1(B->cmap->N, &ab_dense));
282:     PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &cab_dense));
283:     PetscCall(PetscContainerSetPointer(cab_dense, ab_dense));
284:     PetscCall(PetscContainerSetUserDestroy(cab_dense, PetscContainerUserDestroyDefault));
285:     PetscCall(PetscObjectCompose((PetscObject)C, "__PETSc__ab_dense", (PetscObject)cab_dense));
286:     PetscCall(PetscObjectDereference((PetscObject)cab_dense));
287:   }
288:   PetscCall(PetscContainerGetPointer(cab_dense, (void **)&ab_dense));
289:   PetscCall(PetscArrayzero(ab_dense, B->cmap->N));

291:   /* clean old values in C */
292:   PetscCall(PetscArrayzero(ca, ci[cm]));
293:   /* Traverse A row-wise. */
294:   /* Build the ith row in C by summing over nonzero columns in A, */
295:   /* the rows of B corresponding to nonzeros of A. */
296:   for (i = 0; i < am; i++) {
297:     anzi = ai[i + 1] - ai[i];
298:     for (j = 0; j < anzi; j++) {
299:       brow = aj[j];
300:       bnzi = bi[brow + 1] - bi[brow];
301:       bjj  = PetscSafePointerPlusOffset(bj, bi[brow]);
302:       baj  = PetscSafePointerPlusOffset(ba, bi[brow]);
303:       /* perform dense axpy */
304:       valtmp = aa[j];
305:       for (k = 0; k < bnzi; k++) ab_dense[bjj[k]] += valtmp * baj[k];
306:       flops += 2 * bnzi;
307:     }
308:     aj = PetscSafePointerPlusOffset(aj, anzi);
309:     aa = PetscSafePointerPlusOffset(aa, anzi);

311:     cnzi = ci[i + 1] - ci[i];
312:     for (k = 0; k < cnzi; k++) {
313:       ca[k] += ab_dense[cj[k]];
314:       ab_dense[cj[k]] = 0.0; /* zero ab_dense */
315:     }
316:     flops += cnzi;
317:     cj = PetscSafePointerPlusOffset(cj, cnzi);
318:     ca += cnzi;
319:   }
320: #if defined(PETSC_HAVE_DEVICE)
321:   if (C->offloadmask != PETSC_OFFLOAD_UNALLOCATED) C->offloadmask = PETSC_OFFLOAD_CPU;
322: #endif
323:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
324:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
325:   PetscCall(PetscLogFlops(flops));
326:   PetscCall(MatSeqAIJRestoreArrayRead(A, &aa));
327:   PetscCall(MatSeqAIJRestoreArrayRead(B, &ba));
328:   PetscFunctionReturn(PETSC_SUCCESS);
329: }

331: PetscErrorCode MatMatMultNumeric_SeqAIJ_SeqAIJ_Scalable(Mat A, Mat B, Mat C)
332: {
333:   PetscLogDouble     flops = 0.0;
334:   Mat_SeqAIJ        *a     = (Mat_SeqAIJ *)A->data;
335:   Mat_SeqAIJ        *b     = (Mat_SeqAIJ *)B->data;
336:   Mat_SeqAIJ        *c     = (Mat_SeqAIJ *)C->data;
337:   PetscInt          *ai = a->i, *aj = a->j, *bi = b->i, *bj = b->j, *bjj, *ci = c->i, *cj = c->j;
338:   PetscInt           am = A->rmap->N, cm = C->rmap->N;
339:   PetscInt           i, j, k, anzi, bnzi, cnzi, brow;
340:   PetscScalar       *ca = c->a, valtmp;
341:   const PetscScalar *aa, *ba, *baj;
342:   PetscInt           nextb;

344:   PetscFunctionBegin;
345:   PetscCall(MatSeqAIJGetArrayRead(A, &aa));
346:   PetscCall(MatSeqAIJGetArrayRead(B, &ba));
347:   if (!ca) { /* first call of MatMatMultNumeric_SeqAIJ_SeqAIJ, allocate ca and matmult_abdense */
348:     PetscCall(PetscMalloc1(ci[cm] + 1, &ca));
349:     c->a      = ca;
350:     c->free_a = PETSC_TRUE;
351:   }

353:   /* clean old values in C */
354:   PetscCall(PetscArrayzero(ca, ci[cm]));
355:   /* Traverse A row-wise. */
356:   /* Build the ith row in C by summing over nonzero columns in A, */
357:   /* the rows of B corresponding to nonzeros of A. */
358:   for (i = 0; i < am; i++) {
359:     anzi = ai[i + 1] - ai[i];
360:     cnzi = ci[i + 1] - ci[i];
361:     for (j = 0; j < anzi; j++) {
362:       brow = aj[j];
363:       bnzi = bi[brow + 1] - bi[brow];
364:       bjj  = bj + bi[brow];
365:       baj  = ba + bi[brow];
366:       /* perform sparse axpy */
367:       valtmp = aa[j];
368:       nextb  = 0;
369:       for (k = 0; nextb < bnzi; k++) {
370:         if (cj[k] == bjj[nextb]) { /* ccol == bcol */
371:           ca[k] += valtmp * baj[nextb++];
372:         }
373:       }
374:       flops += 2 * bnzi;
375:     }
376:     aj += anzi;
377:     aa += anzi;
378:     cj += cnzi;
379:     ca += cnzi;
380:   }
381: #if defined(PETSC_HAVE_DEVICE)
382:   if (C->offloadmask != PETSC_OFFLOAD_UNALLOCATED) C->offloadmask = PETSC_OFFLOAD_CPU;
383: #endif
384:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
385:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
386:   PetscCall(PetscLogFlops(flops));
387:   PetscCall(MatSeqAIJRestoreArrayRead(A, &aa));
388:   PetscCall(MatSeqAIJRestoreArrayRead(B, &ba));
389:   PetscFunctionReturn(PETSC_SUCCESS);
390: }

392: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ_Scalable_fast(Mat A, Mat B, PetscReal fill, Mat C)
393: {
394:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c;
395:   PetscInt          *ai = a->i, *bi = b->i, *ci, *cj;
396:   PetscInt           am = A->rmap->N, bn = B->cmap->N, bm = B->rmap->N;
397:   MatScalar         *ca;
398:   PetscReal          afill;
399:   PetscInt           i, j, anzi, brow, bnzj, cnzi, *bj, *aj, *lnk, ndouble = 0, Crmax;
400:   PetscHMapI         ta;
401:   PetscFreeSpaceList free_space = NULL, current_space = NULL;

403:   PetscFunctionBegin;
404:   /* Get ci and cj - same as MatMatMultSymbolic_SeqAIJ_SeqAIJ except using PetscLLxxx_fast() */
405:   /* Allocate arrays for fill computation and free space for accumulating nonzero column */
406:   PetscCall(PetscMalloc1(am + 2, &ci));
407:   ci[0] = 0;

409:   /* create and initialize a linked list */
410:   PetscCall(PetscHMapICreateWithSize(bn, &ta));
411:   MatRowMergeMax_SeqAIJ(b, bm, ta);
412:   PetscCall(PetscHMapIGetSize(ta, &Crmax));
413:   PetscCall(PetscHMapIDestroy(&ta));

415:   PetscCall(PetscLLCondensedCreate_fast(Crmax, &lnk));

417:   /* Initial FreeSpace size is fill*(nnz(A)+nnz(B)) */
418:   PetscCall(PetscFreeSpaceGet(PetscRealIntMultTruncate(fill, PetscIntSumTruncate(ai[am], bi[bm])), &free_space));
419:   current_space = free_space;

421:   /* Determine ci and cj */
422:   for (i = 0; i < am; i++) {
423:     anzi = ai[i + 1] - ai[i];
424:     aj   = a->j + ai[i];
425:     for (j = 0; j < anzi; j++) {
426:       brow = aj[j];
427:       bnzj = bi[brow + 1] - bi[brow];
428:       bj   = b->j + bi[brow];
429:       /* add non-zero cols of B into the sorted linked list lnk */
430:       PetscCall(PetscLLCondensedAddSorted_fast(bnzj, bj, lnk));
431:     }
432:     /* add possible missing diagonal entry */
433:     if (C->force_diagonals) PetscCall(PetscLLCondensedAddSorted_fast(1, &i, lnk));
434:     cnzi = lnk[1];

436:     /* If free space is not available, make more free space */
437:     /* Double the amount of total space in the list */
438:     if (current_space->local_remaining < cnzi) {
439:       PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(cnzi, current_space->total_array_size), &current_space));
440:       ndouble++;
441:     }

443:     /* Copy data into free space, then initialize lnk */
444:     PetscCall(PetscLLCondensedClean_fast(cnzi, current_space->array, lnk));

446:     current_space->array += cnzi;
447:     current_space->local_used += cnzi;
448:     current_space->local_remaining -= cnzi;

450:     ci[i + 1] = ci[i] + cnzi;
451:   }

453:   /* Column indices are in the list of free space */
454:   /* Allocate space for cj, initialize cj, and */
455:   /* destroy list of free space and other temporary array(s) */
456:   PetscCall(PetscMalloc1(ci[am] + 1, &cj));
457:   PetscCall(PetscFreeSpaceContiguous(&free_space, cj));
458:   PetscCall(PetscLLCondensedDestroy_fast(lnk));

460:   /* Allocate space for ca */
461:   PetscCall(PetscCalloc1(ci[am] + 1, &ca));

463:   /* put together the new symbolic matrix */
464:   PetscCall(MatSetSeqAIJWithArrays_private(PetscObjectComm((PetscObject)A), am, bn, ci, cj, ca, ((PetscObject)A)->type_name, C));
465:   PetscCall(MatSetBlockSizesFromMats(C, A, B));

467:   /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
468:   /* These are PETSc arrays, so change flags so arrays can be deleted by PETSc */
469:   c          = (Mat_SeqAIJ *)C->data;
470:   c->free_a  = PETSC_TRUE;
471:   c->free_ij = PETSC_TRUE;
472:   c->nonew   = 0;

474:   /* slower, less memory */
475:   C->ops->matmultnumeric = MatMatMultNumeric_SeqAIJ_SeqAIJ_Scalable;

477:   /* set MatInfo */
478:   afill = (PetscReal)ci[am] / (ai[am] + bi[bm]) + 1.e-5;
479:   if (afill < 1.0) afill = 1.0;
480:   C->info.mallocs           = ndouble;
481:   C->info.fill_ratio_given  = fill;
482:   C->info.fill_ratio_needed = afill;

484: #if defined(PETSC_USE_INFO)
485:   if (ci[am]) {
486:     PetscCall(PetscInfo(C, "Reallocs %" PetscInt_FMT "; Fill ratio: given %g needed %g.\n", ndouble, (double)fill, (double)afill));
487:     PetscCall(PetscInfo(C, "Use MatMatMult(A,B,MatReuse,%g,&C) for best performance.;\n", (double)afill));
488:   } else {
489:     PetscCall(PetscInfo(C, "Empty matrix product\n"));
490:   }
491: #endif
492:   PetscFunctionReturn(PETSC_SUCCESS);
493: }

495: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ_Scalable(Mat A, Mat B, PetscReal fill, Mat C)
496: {
497:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c;
498:   PetscInt          *ai = a->i, *bi = b->i, *ci, *cj;
499:   PetscInt           am = A->rmap->N, bn = B->cmap->N, bm = B->rmap->N;
500:   MatScalar         *ca;
501:   PetscReal          afill;
502:   PetscInt           i, j, anzi, brow, bnzj, cnzi, *bj, *aj, *lnk, ndouble = 0, Crmax;
503:   PetscHMapI         ta;
504:   PetscFreeSpaceList free_space = NULL, current_space = NULL;

506:   PetscFunctionBegin;
507:   /* Get ci and cj - same as MatMatMultSymbolic_SeqAIJ_SeqAIJ except using PetscLLxxx_Scalalbe() */
508:   /* Allocate arrays for fill computation and free space for accumulating nonzero column */
509:   PetscCall(PetscMalloc1(am + 2, &ci));
510:   ci[0] = 0;

512:   /* create and initialize a linked list */
513:   PetscCall(PetscHMapICreateWithSize(bn, &ta));
514:   MatRowMergeMax_SeqAIJ(b, bm, ta);
515:   PetscCall(PetscHMapIGetSize(ta, &Crmax));
516:   PetscCall(PetscHMapIDestroy(&ta));
517:   PetscCall(PetscLLCondensedCreate_Scalable(Crmax, &lnk));

519:   /* Initial FreeSpace size is fill*(nnz(A)+nnz(B)) */
520:   PetscCall(PetscFreeSpaceGet(PetscRealIntMultTruncate(fill, PetscIntSumTruncate(ai[am], bi[bm])), &free_space));
521:   current_space = free_space;

523:   /* Determine ci and cj */
524:   for (i = 0; i < am; i++) {
525:     anzi = ai[i + 1] - ai[i];
526:     aj   = a->j + ai[i];
527:     for (j = 0; j < anzi; j++) {
528:       brow = aj[j];
529:       bnzj = bi[brow + 1] - bi[brow];
530:       bj   = b->j + bi[brow];
531:       /* add non-zero cols of B into the sorted linked list lnk */
532:       PetscCall(PetscLLCondensedAddSorted_Scalable(bnzj, bj, lnk));
533:     }
534:     /* add possible missing diagonal entry */
535:     if (C->force_diagonals) PetscCall(PetscLLCondensedAddSorted_Scalable(1, &i, lnk));

537:     cnzi = lnk[0];

539:     /* If free space is not available, make more free space */
540:     /* Double the amount of total space in the list */
541:     if (current_space->local_remaining < cnzi) {
542:       PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(cnzi, current_space->total_array_size), &current_space));
543:       ndouble++;
544:     }

546:     /* Copy data into free space, then initialize lnk */
547:     PetscCall(PetscLLCondensedClean_Scalable(cnzi, current_space->array, lnk));

549:     current_space->array += cnzi;
550:     current_space->local_used += cnzi;
551:     current_space->local_remaining -= cnzi;

553:     ci[i + 1] = ci[i] + cnzi;
554:   }

556:   /* Column indices are in the list of free space */
557:   /* Allocate space for cj, initialize cj, and */
558:   /* destroy list of free space and other temporary array(s) */
559:   PetscCall(PetscMalloc1(ci[am] + 1, &cj));
560:   PetscCall(PetscFreeSpaceContiguous(&free_space, cj));
561:   PetscCall(PetscLLCondensedDestroy_Scalable(lnk));

563:   /* Allocate space for ca */
564:   PetscCall(PetscCalloc1(ci[am] + 1, &ca));

566:   /* put together the new symbolic matrix */
567:   PetscCall(MatSetSeqAIJWithArrays_private(PetscObjectComm((PetscObject)A), am, bn, ci, cj, ca, ((PetscObject)A)->type_name, C));
568:   PetscCall(MatSetBlockSizesFromMats(C, A, B));

570:   /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
571:   /* These are PETSc arrays, so change flags so arrays can be deleted by PETSc */
572:   c          = (Mat_SeqAIJ *)C->data;
573:   c->free_a  = PETSC_TRUE;
574:   c->free_ij = PETSC_TRUE;
575:   c->nonew   = 0;

577:   /* slower, less memory */
578:   C->ops->matmultnumeric = MatMatMultNumeric_SeqAIJ_SeqAIJ_Scalable;

580:   /* set MatInfo */
581:   afill = (PetscReal)ci[am] / (ai[am] + bi[bm]) + 1.e-5;
582:   if (afill < 1.0) afill = 1.0;
583:   C->info.mallocs           = ndouble;
584:   C->info.fill_ratio_given  = fill;
585:   C->info.fill_ratio_needed = afill;

587: #if defined(PETSC_USE_INFO)
588:   if (ci[am]) {
589:     PetscCall(PetscInfo(C, "Reallocs %" PetscInt_FMT "; Fill ratio: given %g needed %g.\n", ndouble, (double)fill, (double)afill));
590:     PetscCall(PetscInfo(C, "Use MatMatMult(A,B,MatReuse,%g,&C) for best performance.;\n", (double)afill));
591:   } else {
592:     PetscCall(PetscInfo(C, "Empty matrix product\n"));
593:   }
594: #endif
595:   PetscFunctionReturn(PETSC_SUCCESS);
596: }

598: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ_Heap(Mat A, Mat B, PetscReal fill, Mat C)
599: {
600:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c;
601:   const PetscInt    *ai = a->i, *bi = b->i, *aj = a->j, *bj = b->j;
602:   PetscInt          *ci, *cj, *bb;
603:   PetscInt           am = A->rmap->N, bn = B->cmap->N, bm = B->rmap->N;
604:   PetscReal          afill;
605:   PetscInt           i, j, col, ndouble = 0;
606:   PetscFreeSpaceList free_space = NULL, current_space = NULL;
607:   PetscHeap          h;

609:   PetscFunctionBegin;
610:   /* Get ci and cj - by merging sorted rows using a heap */
611:   /* Allocate arrays for fill computation and free space for accumulating nonzero column */
612:   PetscCall(PetscMalloc1(am + 2, &ci));
613:   ci[0] = 0;

615:   /* Initial FreeSpace size is fill*(nnz(A)+nnz(B)) */
616:   PetscCall(PetscFreeSpaceGet(PetscRealIntMultTruncate(fill, PetscIntSumTruncate(ai[am], bi[bm])), &free_space));
617:   current_space = free_space;

619:   PetscCall(PetscHeapCreate(a->rmax, &h));
620:   PetscCall(PetscMalloc1(a->rmax, &bb));

622:   /* Determine ci and cj */
623:   for (i = 0; i < am; i++) {
624:     const PetscInt  anzi = ai[i + 1] - ai[i]; /* number of nonzeros in this row of A, this is the number of rows of B that we merge */
625:     const PetscInt *acol = aj + ai[i];        /* column indices of nonzero entries in this row */
626:     ci[i + 1]            = ci[i];
627:     /* Populate the min heap */
628:     for (j = 0; j < anzi; j++) {
629:       bb[j] = bi[acol[j]];           /* bb points at the start of the row */
630:       if (bb[j] < bi[acol[j] + 1]) { /* Add if row is nonempty */
631:         PetscCall(PetscHeapAdd(h, j, bj[bb[j]++]));
632:       }
633:     }
634:     /* Pick off the min element, adding it to free space */
635:     PetscCall(PetscHeapPop(h, &j, &col));
636:     while (j >= 0) {
637:       if (current_space->local_remaining < 1) { /* double the size, but don't exceed 16 MiB */
638:         PetscCall(PetscFreeSpaceGet(PetscMin(PetscIntMultTruncate(2, current_space->total_array_size), 16 << 20), &current_space));
639:         ndouble++;
640:       }
641:       *(current_space->array++) = col;
642:       current_space->local_used++;
643:       current_space->local_remaining--;
644:       ci[i + 1]++;

646:       /* stash if anything else remains in this row of B */
647:       if (bb[j] < bi[acol[j] + 1]) PetscCall(PetscHeapStash(h, j, bj[bb[j]++]));
648:       while (1) { /* pop and stash any other rows of B that also had an entry in this column */
649:         PetscInt j2, col2;
650:         PetscCall(PetscHeapPeek(h, &j2, &col2));
651:         if (col2 != col) break;
652:         PetscCall(PetscHeapPop(h, &j2, &col2));
653:         if (bb[j2] < bi[acol[j2] + 1]) PetscCall(PetscHeapStash(h, j2, bj[bb[j2]++]));
654:       }
655:       /* Put any stashed elements back into the min heap */
656:       PetscCall(PetscHeapUnstash(h));
657:       PetscCall(PetscHeapPop(h, &j, &col));
658:     }
659:   }
660:   PetscCall(PetscFree(bb));
661:   PetscCall(PetscHeapDestroy(&h));

663:   /* Column indices are in the list of free space */
664:   /* Allocate space for cj, initialize cj, and */
665:   /* destroy list of free space and other temporary array(s) */
666:   PetscCall(PetscMalloc1(ci[am], &cj));
667:   PetscCall(PetscFreeSpaceContiguous(&free_space, cj));

669:   /* put together the new symbolic matrix */
670:   PetscCall(MatSetSeqAIJWithArrays_private(PetscObjectComm((PetscObject)A), am, bn, ci, cj, NULL, ((PetscObject)A)->type_name, C));
671:   PetscCall(MatSetBlockSizesFromMats(C, A, B));

673:   /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
674:   /* These are PETSc arrays, so change flags so arrays can be deleted by PETSc */
675:   c          = (Mat_SeqAIJ *)C->data;
676:   c->free_a  = PETSC_TRUE;
677:   c->free_ij = PETSC_TRUE;
678:   c->nonew   = 0;

680:   C->ops->matmultnumeric = MatMatMultNumeric_SeqAIJ_SeqAIJ_Sorted;

682:   /* set MatInfo */
683:   afill = (PetscReal)ci[am] / (ai[am] + bi[bm]) + 1.e-5;
684:   if (afill < 1.0) afill = 1.0;
685:   C->info.mallocs           = ndouble;
686:   C->info.fill_ratio_given  = fill;
687:   C->info.fill_ratio_needed = afill;

689: #if defined(PETSC_USE_INFO)
690:   if (ci[am]) {
691:     PetscCall(PetscInfo(C, "Reallocs %" PetscInt_FMT "; Fill ratio: given %g needed %g.\n", ndouble, (double)fill, (double)afill));
692:     PetscCall(PetscInfo(C, "Use MatMatMult(A,B,MatReuse,%g,&C) for best performance.;\n", (double)afill));
693:   } else {
694:     PetscCall(PetscInfo(C, "Empty matrix product\n"));
695:   }
696: #endif
697:   PetscFunctionReturn(PETSC_SUCCESS);
698: }

700: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ_BTHeap(Mat A, Mat B, PetscReal fill, Mat C)
701: {
702:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c;
703:   const PetscInt    *ai = a->i, *bi = b->i, *aj = a->j, *bj = b->j;
704:   PetscInt          *ci, *cj, *bb;
705:   PetscInt           am = A->rmap->N, bn = B->cmap->N, bm = B->rmap->N;
706:   PetscReal          afill;
707:   PetscInt           i, j, col, ndouble = 0;
708:   PetscFreeSpaceList free_space = NULL, current_space = NULL;
709:   PetscHeap          h;
710:   PetscBT            bt;

712:   PetscFunctionBegin;
713:   /* Get ci and cj - using a heap for the sorted rows, but use BT so that each index is only added once */
714:   /* Allocate arrays for fill computation and free space for accumulating nonzero column */
715:   PetscCall(PetscMalloc1(am + 2, &ci));
716:   ci[0] = 0;

718:   /* Initial FreeSpace size is fill*(nnz(A)+nnz(B)) */
719:   PetscCall(PetscFreeSpaceGet(PetscRealIntMultTruncate(fill, PetscIntSumTruncate(ai[am], bi[bm])), &free_space));

721:   current_space = free_space;

723:   PetscCall(PetscHeapCreate(a->rmax, &h));
724:   PetscCall(PetscMalloc1(a->rmax, &bb));
725:   PetscCall(PetscBTCreate(bn, &bt));

727:   /* Determine ci and cj */
728:   for (i = 0; i < am; i++) {
729:     const PetscInt  anzi = ai[i + 1] - ai[i];    /* number of nonzeros in this row of A, this is the number of rows of B that we merge */
730:     const PetscInt *acol = aj + ai[i];           /* column indices of nonzero entries in this row */
731:     const PetscInt *fptr = current_space->array; /* Save beginning of the row so we can clear the BT later */
732:     ci[i + 1]            = ci[i];
733:     /* Populate the min heap */
734:     for (j = 0; j < anzi; j++) {
735:       PetscInt brow = acol[j];
736:       for (bb[j] = bi[brow]; bb[j] < bi[brow + 1]; bb[j]++) {
737:         PetscInt bcol = bj[bb[j]];
738:         if (!PetscBTLookupSet(bt, bcol)) { /* new entry */
739:           PetscCall(PetscHeapAdd(h, j, bcol));
740:           bb[j]++;
741:           break;
742:         }
743:       }
744:     }
745:     /* Pick off the min element, adding it to free space */
746:     PetscCall(PetscHeapPop(h, &j, &col));
747:     while (j >= 0) {
748:       if (current_space->local_remaining < 1) { /* double the size, but don't exceed 16 MiB */
749:         fptr = NULL;                            /* need PetscBTMemzero */
750:         PetscCall(PetscFreeSpaceGet(PetscMin(PetscIntMultTruncate(2, current_space->total_array_size), 16 << 20), &current_space));
751:         ndouble++;
752:       }
753:       *(current_space->array++) = col;
754:       current_space->local_used++;
755:       current_space->local_remaining--;
756:       ci[i + 1]++;

758:       /* stash if anything else remains in this row of B */
759:       for (; bb[j] < bi[acol[j] + 1]; bb[j]++) {
760:         PetscInt bcol = bj[bb[j]];
761:         if (!PetscBTLookupSet(bt, bcol)) { /* new entry */
762:           PetscCall(PetscHeapAdd(h, j, bcol));
763:           bb[j]++;
764:           break;
765:         }
766:       }
767:       PetscCall(PetscHeapPop(h, &j, &col));
768:     }
769:     if (fptr) { /* Clear the bits for this row */
770:       for (; fptr < current_space->array; fptr++) PetscCall(PetscBTClear(bt, *fptr));
771:     } else { /* We reallocated so we don't remember (easily) how to clear only the bits we changed */
772:       PetscCall(PetscBTMemzero(bn, bt));
773:     }
774:   }
775:   PetscCall(PetscFree(bb));
776:   PetscCall(PetscHeapDestroy(&h));
777:   PetscCall(PetscBTDestroy(&bt));

779:   /* Column indices are in the list of free space */
780:   /* Allocate space for cj, initialize cj, and */
781:   /* destroy list of free space and other temporary array(s) */
782:   PetscCall(PetscMalloc1(ci[am], &cj));
783:   PetscCall(PetscFreeSpaceContiguous(&free_space, cj));

785:   /* put together the new symbolic matrix */
786:   PetscCall(MatSetSeqAIJWithArrays_private(PetscObjectComm((PetscObject)A), am, bn, ci, cj, NULL, ((PetscObject)A)->type_name, C));
787:   PetscCall(MatSetBlockSizesFromMats(C, A, B));

789:   /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
790:   /* These are PETSc arrays, so change flags so arrays can be deleted by PETSc */
791:   c          = (Mat_SeqAIJ *)C->data;
792:   c->free_a  = PETSC_TRUE;
793:   c->free_ij = PETSC_TRUE;
794:   c->nonew   = 0;

796:   C->ops->matmultnumeric = MatMatMultNumeric_SeqAIJ_SeqAIJ_Sorted;

798:   /* set MatInfo */
799:   afill = (PetscReal)ci[am] / (ai[am] + bi[bm]) + 1.e-5;
800:   if (afill < 1.0) afill = 1.0;
801:   C->info.mallocs           = ndouble;
802:   C->info.fill_ratio_given  = fill;
803:   C->info.fill_ratio_needed = afill;

805: #if defined(PETSC_USE_INFO)
806:   if (ci[am]) {
807:     PetscCall(PetscInfo(C, "Reallocs %" PetscInt_FMT "; Fill ratio: given %g needed %g.\n", ndouble, (double)fill, (double)afill));
808:     PetscCall(PetscInfo(C, "Use MatMatMult(A,B,MatReuse,%g,&C) for best performance.;\n", (double)afill));
809:   } else {
810:     PetscCall(PetscInfo(C, "Empty matrix product\n"));
811:   }
812: #endif
813:   PetscFunctionReturn(PETSC_SUCCESS);
814: }

816: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ_RowMerge(Mat A, Mat B, PetscReal fill, Mat C)
817: {
818:   Mat_SeqAIJ     *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c;
819:   const PetscInt *ai = a->i, *bi = b->i, *aj = a->j, *bj = b->j, *inputi, *inputj, *inputcol, *inputcol_L1;
820:   PetscInt       *ci, *cj, *outputj, worki_L1[9], worki_L2[9];
821:   PetscInt        c_maxmem, a_maxrownnz = 0, a_rownnz;
822:   const PetscInt  workcol[8] = {0, 1, 2, 3, 4, 5, 6, 7};
823:   const PetscInt  am = A->rmap->N, bn = B->cmap->N, bm = B->rmap->N;
824:   const PetscInt *brow_ptr[8], *brow_end[8];
825:   PetscInt        window[8];
826:   PetscInt        window_min, old_window_min, ci_nnz, outputi_nnz = 0, L1_nrows, L2_nrows;
827:   PetscInt        i, k, ndouble = 0, L1_rowsleft, rowsleft;
828:   PetscReal       afill;
829:   PetscInt       *workj_L1, *workj_L2, *workj_L3;
830:   PetscInt        L1_nnz, L2_nnz;

832:   /* Step 1: Get upper bound on memory required for allocation.
833:              Because of the way virtual memory works,
834:              only the memory pages that are actually needed will be physically allocated. */
835:   PetscFunctionBegin;
836:   PetscCall(PetscMalloc1(am + 1, &ci));
837:   for (i = 0; i < am; i++) {
838:     const PetscInt  anzi = ai[i + 1] - ai[i]; /* number of nonzeros in this row of A, this is the number of rows of B that we merge */
839:     const PetscInt *acol = aj + ai[i];        /* column indices of nonzero entries in this row */
840:     a_rownnz             = 0;
841:     for (k = 0; k < anzi; ++k) {
842:       a_rownnz += bi[acol[k] + 1] - bi[acol[k]];
843:       if (a_rownnz > bn) {
844:         a_rownnz = bn;
845:         break;
846:       }
847:     }
848:     a_maxrownnz = PetscMax(a_maxrownnz, a_rownnz);
849:   }
850:   /* temporary work areas for merging rows */
851:   PetscCall(PetscMalloc1(a_maxrownnz * 8, &workj_L1));
852:   PetscCall(PetscMalloc1(a_maxrownnz * 8, &workj_L2));
853:   PetscCall(PetscMalloc1(a_maxrownnz, &workj_L3));

855:   /* This should be enough for almost all matrices. If not, memory is reallocated later. */
856:   c_maxmem = 8 * (ai[am] + bi[bm]);
857:   /* Step 2: Populate pattern for C */
858:   PetscCall(PetscMalloc1(c_maxmem, &cj));

860:   ci_nnz      = 0;
861:   ci[0]       = 0;
862:   worki_L1[0] = 0;
863:   worki_L2[0] = 0;
864:   for (i = 0; i < am; i++) {
865:     const PetscInt  anzi = ai[i + 1] - ai[i]; /* number of nonzeros in this row of A, this is the number of rows of B that we merge */
866:     const PetscInt *acol = aj + ai[i];        /* column indices of nonzero entries in this row */
867:     rowsleft             = anzi;
868:     inputcol_L1          = acol;
869:     L2_nnz               = 0;
870:     L2_nrows             = 1; /* Number of rows to be merged on Level 3. output of L3 already exists -> initial value 1   */
871:     worki_L2[1]          = 0;
872:     outputi_nnz          = 0;

874:     /* If the number of indices in C so far + the max number of columns in the next row > c_maxmem  -> allocate more memory */
875:     while (ci_nnz + a_maxrownnz > c_maxmem) {
876:       c_maxmem *= 2;
877:       ndouble++;
878:       PetscCall(PetscRealloc(sizeof(PetscInt) * c_maxmem, &cj));
879:     }

881:     while (rowsleft) {
882:       L1_rowsleft = PetscMin(64, rowsleft); /* In the inner loop max 64 rows of B can be merged */
883:       L1_nrows    = 0;
884:       L1_nnz      = 0;
885:       inputcol    = inputcol_L1;
886:       inputi      = bi;
887:       inputj      = bj;

889:       /* The following macro is used to specialize for small rows in A.
890:          This helps with compiler unrolling, improving performance substantially.
891:           Input:  inputj   inputi  inputcol  bn
892:           Output: outputj  outputi_nnz                       */
893: #define MatMatMultSymbolic_RowMergeMacro(ANNZ) \
894:   do { \
895:     window_min  = bn; \
896:     outputi_nnz = 0; \
897:     for (k = 0; k < ANNZ; ++k) { \
898:       brow_ptr[k] = inputj + inputi[inputcol[k]]; \
899:       brow_end[k] = inputj + inputi[inputcol[k] + 1]; \
900:       window[k]   = (brow_ptr[k] != brow_end[k]) ? *brow_ptr[k] : bn; \
901:       window_min  = PetscMin(window[k], window_min); \
902:     } \
903:     while (window_min < bn) { \
904:       outputj[outputi_nnz++] = window_min; \
905:       /* advance front and compute new minimum */ \
906:       old_window_min = window_min; \
907:       window_min     = bn; \
908:       for (k = 0; k < ANNZ; ++k) { \
909:         if (window[k] == old_window_min) { \
910:           brow_ptr[k]++; \
911:           window[k] = (brow_ptr[k] != brow_end[k]) ? *brow_ptr[k] : bn; \
912:         } \
913:         window_min = PetscMin(window[k], window_min); \
914:       } \
915:     } \
916:   } while (0)

918:       /************** L E V E L  1 ***************/
919:       /* Merge up to 8 rows of B to L1 work array*/
920:       while (L1_rowsleft) {
921:         outputi_nnz = 0;
922:         if (anzi > 8) outputj = workj_L1 + L1_nnz; /* Level 1 rowmerge*/
923:         else outputj = cj + ci_nnz;                /* Merge directly to C */

925:         switch (L1_rowsleft) {
926:         case 1:
927:           brow_ptr[0] = inputj + inputi[inputcol[0]];
928:           brow_end[0] = inputj + inputi[inputcol[0] + 1];
929:           for (; brow_ptr[0] != brow_end[0]; ++brow_ptr[0]) outputj[outputi_nnz++] = *brow_ptr[0]; /* copy row in b over */
930:           inputcol += L1_rowsleft;
931:           rowsleft -= L1_rowsleft;
932:           L1_rowsleft = 0;
933:           break;
934:         case 2:
935:           MatMatMultSymbolic_RowMergeMacro(2);
936:           inputcol += L1_rowsleft;
937:           rowsleft -= L1_rowsleft;
938:           L1_rowsleft = 0;
939:           break;
940:         case 3:
941:           MatMatMultSymbolic_RowMergeMacro(3);
942:           inputcol += L1_rowsleft;
943:           rowsleft -= L1_rowsleft;
944:           L1_rowsleft = 0;
945:           break;
946:         case 4:
947:           MatMatMultSymbolic_RowMergeMacro(4);
948:           inputcol += L1_rowsleft;
949:           rowsleft -= L1_rowsleft;
950:           L1_rowsleft = 0;
951:           break;
952:         case 5:
953:           MatMatMultSymbolic_RowMergeMacro(5);
954:           inputcol += L1_rowsleft;
955:           rowsleft -= L1_rowsleft;
956:           L1_rowsleft = 0;
957:           break;
958:         case 6:
959:           MatMatMultSymbolic_RowMergeMacro(6);
960:           inputcol += L1_rowsleft;
961:           rowsleft -= L1_rowsleft;
962:           L1_rowsleft = 0;
963:           break;
964:         case 7:
965:           MatMatMultSymbolic_RowMergeMacro(7);
966:           inputcol += L1_rowsleft;
967:           rowsleft -= L1_rowsleft;
968:           L1_rowsleft = 0;
969:           break;
970:         default:
971:           MatMatMultSymbolic_RowMergeMacro(8);
972:           inputcol += 8;
973:           rowsleft -= 8;
974:           L1_rowsleft -= 8;
975:           break;
976:         }
977:         inputcol_L1 = inputcol;
978:         L1_nnz += outputi_nnz;
979:         worki_L1[++L1_nrows] = L1_nnz;
980:       }

982:       /********************** L E V E L  2 ************************/
983:       /* Merge from L1 work array to either C or to L2 work array */
984:       if (anzi > 8) {
985:         inputi      = worki_L1;
986:         inputj      = workj_L1;
987:         inputcol    = workcol;
988:         outputi_nnz = 0;

990:         if (anzi <= 64) outputj = cj + ci_nnz; /* Merge from L1 work array to C */
991:         else outputj = workj_L2 + L2_nnz;      /* Merge from L1 work array to L2 work array */

993:         switch (L1_nrows) {
994:         case 1:
995:           brow_ptr[0] = inputj + inputi[inputcol[0]];
996:           brow_end[0] = inputj + inputi[inputcol[0] + 1];
997:           for (; brow_ptr[0] != brow_end[0]; ++brow_ptr[0]) outputj[outputi_nnz++] = *brow_ptr[0]; /* copy row in b over */
998:           break;
999:         case 2:
1000:           MatMatMultSymbolic_RowMergeMacro(2);
1001:           break;
1002:         case 3:
1003:           MatMatMultSymbolic_RowMergeMacro(3);
1004:           break;
1005:         case 4:
1006:           MatMatMultSymbolic_RowMergeMacro(4);
1007:           break;
1008:         case 5:
1009:           MatMatMultSymbolic_RowMergeMacro(5);
1010:           break;
1011:         case 6:
1012:           MatMatMultSymbolic_RowMergeMacro(6);
1013:           break;
1014:         case 7:
1015:           MatMatMultSymbolic_RowMergeMacro(7);
1016:           break;
1017:         case 8:
1018:           MatMatMultSymbolic_RowMergeMacro(8);
1019:           break;
1020:         default:
1021:           SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "MatMatMult logic error: Not merging 1-8 rows from L1 work array!");
1022:         }
1023:         L2_nnz += outputi_nnz;
1024:         worki_L2[++L2_nrows] = L2_nnz;

1026:         /************************ L E V E L  3 **********************/
1027:         /* Merge from L2 work array to either C or to L2 work array */
1028:         if (anzi > 64 && (L2_nrows == 8 || rowsleft == 0)) {
1029:           inputi      = worki_L2;
1030:           inputj      = workj_L2;
1031:           inputcol    = workcol;
1032:           outputi_nnz = 0;
1033:           if (rowsleft) outputj = workj_L3;
1034:           else outputj = cj + ci_nnz;
1035:           switch (L2_nrows) {
1036:           case 1:
1037:             brow_ptr[0] = inputj + inputi[inputcol[0]];
1038:             brow_end[0] = inputj + inputi[inputcol[0] + 1];
1039:             for (; brow_ptr[0] != brow_end[0]; ++brow_ptr[0]) outputj[outputi_nnz++] = *brow_ptr[0]; /* copy row in b over */
1040:             break;
1041:           case 2:
1042:             MatMatMultSymbolic_RowMergeMacro(2);
1043:             break;
1044:           case 3:
1045:             MatMatMultSymbolic_RowMergeMacro(3);
1046:             break;
1047:           case 4:
1048:             MatMatMultSymbolic_RowMergeMacro(4);
1049:             break;
1050:           case 5:
1051:             MatMatMultSymbolic_RowMergeMacro(5);
1052:             break;
1053:           case 6:
1054:             MatMatMultSymbolic_RowMergeMacro(6);
1055:             break;
1056:           case 7:
1057:             MatMatMultSymbolic_RowMergeMacro(7);
1058:             break;
1059:           case 8:
1060:             MatMatMultSymbolic_RowMergeMacro(8);
1061:             break;
1062:           default:
1063:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "MatMatMult logic error: Not merging 1-8 rows from L2 work array!");
1064:           }
1065:           L2_nrows    = 1;
1066:           L2_nnz      = outputi_nnz;
1067:           worki_L2[1] = outputi_nnz;
1068:           /* Copy to workj_L2 */
1069:           if (rowsleft) {
1070:             for (k = 0; k < outputi_nnz; ++k) workj_L2[k] = outputj[k];
1071:           }
1072:         }
1073:       }
1074:     } /* while (rowsleft) */
1075: #undef MatMatMultSymbolic_RowMergeMacro

1077:     /* terminate current row */
1078:     ci_nnz += outputi_nnz;
1079:     ci[i + 1] = ci_nnz;
1080:   }

1082:   /* Step 3: Create the new symbolic matrix */
1083:   PetscCall(MatSetSeqAIJWithArrays_private(PetscObjectComm((PetscObject)A), am, bn, ci, cj, NULL, ((PetscObject)A)->type_name, C));
1084:   PetscCall(MatSetBlockSizesFromMats(C, A, B));

1086:   /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
1087:   /* These are PETSc arrays, so change flags so arrays can be deleted by PETSc */
1088:   c          = (Mat_SeqAIJ *)C->data;
1089:   c->free_a  = PETSC_TRUE;
1090:   c->free_ij = PETSC_TRUE;
1091:   c->nonew   = 0;

1093:   C->ops->matmultnumeric = MatMatMultNumeric_SeqAIJ_SeqAIJ_Sorted;

1095:   /* set MatInfo */
1096:   afill = (PetscReal)ci[am] / (ai[am] + bi[bm]) + 1.e-5;
1097:   if (afill < 1.0) afill = 1.0;
1098:   C->info.mallocs           = ndouble;
1099:   C->info.fill_ratio_given  = fill;
1100:   C->info.fill_ratio_needed = afill;

1102: #if defined(PETSC_USE_INFO)
1103:   if (ci[am]) {
1104:     PetscCall(PetscInfo(C, "Reallocs %" PetscInt_FMT "; Fill ratio: given %g needed %g.\n", ndouble, (double)fill, (double)afill));
1105:     PetscCall(PetscInfo(C, "Use MatMatMult(A,B,MatReuse,%g,&C) for best performance.;\n", (double)afill));
1106:   } else {
1107:     PetscCall(PetscInfo(C, "Empty matrix product\n"));
1108:   }
1109: #endif

1111:   /* Step 4: Free temporary work areas */
1112:   PetscCall(PetscFree(workj_L1));
1113:   PetscCall(PetscFree(workj_L2));
1114:   PetscCall(PetscFree(workj_L3));
1115:   PetscFunctionReturn(PETSC_SUCCESS);
1116: }

1118: /* concatenate unique entries and then sort */
1119: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ_Sorted(Mat A, Mat B, PetscReal fill, Mat C)
1120: {
1121:   Mat_SeqAIJ     *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c;
1122:   const PetscInt *ai = a->i, *bi = b->i, *aj = a->j, *bj = b->j;
1123:   PetscInt       *ci, *cj, bcol;
1124:   PetscInt        am = A->rmap->N, bn = B->cmap->N, bm = B->rmap->N;
1125:   PetscReal       afill;
1126:   PetscInt        i, j, ndouble = 0;
1127:   PetscSegBuffer  seg, segrow;
1128:   char           *seen;

1130:   PetscFunctionBegin;
1131:   PetscCall(PetscMalloc1(am + 1, &ci));
1132:   ci[0] = 0;

1134:   /* Initial FreeSpace size is fill*(nnz(A)+nnz(B)) */
1135:   PetscCall(PetscSegBufferCreate(sizeof(PetscInt), (PetscInt)(fill * (ai[am] + bi[bm])), &seg));
1136:   PetscCall(PetscSegBufferCreate(sizeof(PetscInt), 100, &segrow));
1137:   PetscCall(PetscCalloc1(bn, &seen));

1139:   /* Determine ci and cj */
1140:   for (i = 0; i < am; i++) {
1141:     const PetscInt  anzi = ai[i + 1] - ai[i];                     /* number of nonzeros in this row of A, this is the number of rows of B that we merge */
1142:     const PetscInt *acol = PetscSafePointerPlusOffset(aj, ai[i]); /* column indices of nonzero entries in this row */
1143:     PetscInt packlen     = 0, *PETSC_RESTRICT crow;

1145:     /* Pack segrow */
1146:     for (j = 0; j < anzi; j++) {
1147:       PetscInt brow = acol[j], bjstart = bi[brow], bjend = bi[brow + 1], k;
1148:       for (k = bjstart; k < bjend; k++) {
1149:         bcol = bj[k];
1150:         if (!seen[bcol]) { /* new entry */
1151:           PetscInt *PETSC_RESTRICT slot;
1152:           PetscCall(PetscSegBufferGetInts(segrow, 1, &slot));
1153:           *slot      = bcol;
1154:           seen[bcol] = 1;
1155:           packlen++;
1156:         }
1157:       }
1158:     }

1160:     /* Check i-th diagonal entry */
1161:     if (C->force_diagonals && !seen[i]) {
1162:       PetscInt *PETSC_RESTRICT slot;
1163:       PetscCall(PetscSegBufferGetInts(segrow, 1, &slot));
1164:       *slot   = i;
1165:       seen[i] = 1;
1166:       packlen++;
1167:     }

1169:     PetscCall(PetscSegBufferGetInts(seg, packlen, &crow));
1170:     PetscCall(PetscSegBufferExtractTo(segrow, crow));
1171:     PetscCall(PetscSortInt(packlen, crow));
1172:     ci[i + 1] = ci[i] + packlen;
1173:     for (j = 0; j < packlen; j++) seen[crow[j]] = 0;
1174:   }
1175:   PetscCall(PetscSegBufferDestroy(&segrow));
1176:   PetscCall(PetscFree(seen));

1178:   /* Column indices are in the segmented buffer */
1179:   PetscCall(PetscSegBufferExtractAlloc(seg, &cj));
1180:   PetscCall(PetscSegBufferDestroy(&seg));

1182:   /* put together the new symbolic matrix */
1183:   PetscCall(MatSetSeqAIJWithArrays_private(PetscObjectComm((PetscObject)A), am, bn, ci, cj, NULL, ((PetscObject)A)->type_name, C));
1184:   PetscCall(MatSetBlockSizesFromMats(C, A, B));

1186:   /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
1187:   /* These are PETSc arrays, so change flags so arrays can be deleted by PETSc */
1188:   c          = (Mat_SeqAIJ *)C->data;
1189:   c->free_a  = PETSC_TRUE;
1190:   c->free_ij = PETSC_TRUE;
1191:   c->nonew   = 0;

1193:   C->ops->matmultnumeric = MatMatMultNumeric_SeqAIJ_SeqAIJ_Sorted;

1195:   /* set MatInfo */
1196:   afill = (PetscReal)ci[am] / PetscMax(ai[am] + bi[bm], 1) + 1.e-5;
1197:   if (afill < 1.0) afill = 1.0;
1198:   C->info.mallocs           = ndouble;
1199:   C->info.fill_ratio_given  = fill;
1200:   C->info.fill_ratio_needed = afill;

1202: #if defined(PETSC_USE_INFO)
1203:   if (ci[am]) {
1204:     PetscCall(PetscInfo(C, "Reallocs %" PetscInt_FMT "; Fill ratio: given %g needed %g.\n", ndouble, (double)fill, (double)afill));
1205:     PetscCall(PetscInfo(C, "Use MatMatMult(A,B,MatReuse,%g,&C) for best performance.;\n", (double)afill));
1206:   } else {
1207:     PetscCall(PetscInfo(C, "Empty matrix product\n"));
1208:   }
1209: #endif
1210:   PetscFunctionReturn(PETSC_SUCCESS);
1211: }

1213: static PetscErrorCode MatDestroy_SeqAIJ_MatMatMultTrans(void *data)
1214: {
1215:   Mat_MatMatTransMult *abt = (Mat_MatMatTransMult *)data;

1217:   PetscFunctionBegin;
1218:   PetscCall(MatTransposeColoringDestroy(&abt->matcoloring));
1219:   PetscCall(MatDestroy(&abt->Bt_den));
1220:   PetscCall(MatDestroy(&abt->ABt_den));
1221:   PetscCall(PetscFree(abt));
1222:   PetscFunctionReturn(PETSC_SUCCESS);
1223: }

1225: PetscErrorCode MatMatTransposeMultSymbolic_SeqAIJ_SeqAIJ(Mat A, Mat B, PetscReal fill, Mat C)
1226: {
1227:   Mat                  Bt;
1228:   Mat_MatMatTransMult *abt;
1229:   Mat_Product         *product = C->product;
1230:   char                *alg;

1232:   PetscFunctionBegin;
1233:   PetscCheck(product, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Missing product struct");
1234:   PetscCheck(!product->data, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Extra product struct not empty");

1236:   /* create symbolic Bt */
1237:   PetscCall(MatTransposeSymbolic(B, &Bt));
1238:   PetscCall(MatSetBlockSizes(Bt, PetscAbs(A->cmap->bs), PetscAbs(B->cmap->bs)));
1239:   PetscCall(MatSetType(Bt, ((PetscObject)A)->type_name));

1241:   /* get symbolic C=A*Bt */
1242:   PetscCall(PetscStrallocpy(product->alg, &alg));
1243:   PetscCall(MatProductSetAlgorithm(C, "sorted")); /* set algorithm for C = A*Bt */
1244:   PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ(A, Bt, fill, C));
1245:   PetscCall(MatProductSetAlgorithm(C, alg)); /* resume original algorithm for ABt product */
1246:   PetscCall(PetscFree(alg));

1248:   /* create a supporting struct for reuse intermediate dense matrices with matcoloring */
1249:   PetscCall(PetscNew(&abt));

1251:   product->data    = abt;
1252:   product->destroy = MatDestroy_SeqAIJ_MatMatMultTrans;

1254:   C->ops->mattransposemultnumeric = MatMatTransposeMultNumeric_SeqAIJ_SeqAIJ;

1256:   abt->usecoloring = PETSC_FALSE;
1257:   PetscCall(PetscStrcmp(product->alg, "color", &abt->usecoloring));
1258:   if (abt->usecoloring) {
1259:     /* Create MatTransposeColoring from symbolic C=A*B^T */
1260:     MatTransposeColoring matcoloring;
1261:     MatColoring          coloring;
1262:     ISColoring           iscoloring;
1263:     Mat                  Bt_dense, C_dense;

1265:     /* inode causes memory problem */
1266:     PetscCall(MatSetOption(C, MAT_USE_INODES, PETSC_FALSE));

1268:     PetscCall(MatColoringCreate(C, &coloring));
1269:     PetscCall(MatColoringSetDistance(coloring, 2));
1270:     PetscCall(MatColoringSetType(coloring, MATCOLORINGSL));
1271:     PetscCall(MatColoringSetFromOptions(coloring));
1272:     PetscCall(MatColoringApply(coloring, &iscoloring));
1273:     PetscCall(MatColoringDestroy(&coloring));
1274:     PetscCall(MatTransposeColoringCreate(C, iscoloring, &matcoloring));

1276:     abt->matcoloring = matcoloring;

1278:     PetscCall(ISColoringDestroy(&iscoloring));

1280:     /* Create Bt_dense and C_dense = A*Bt_dense */
1281:     PetscCall(MatCreate(PETSC_COMM_SELF, &Bt_dense));
1282:     PetscCall(MatSetSizes(Bt_dense, A->cmap->n, matcoloring->ncolors, A->cmap->n, matcoloring->ncolors));
1283:     PetscCall(MatSetType(Bt_dense, MATSEQDENSE));
1284:     PetscCall(MatSeqDenseSetPreallocation(Bt_dense, NULL));

1286:     Bt_dense->assembled = PETSC_TRUE;
1287:     abt->Bt_den         = Bt_dense;

1289:     PetscCall(MatCreate(PETSC_COMM_SELF, &C_dense));
1290:     PetscCall(MatSetSizes(C_dense, A->rmap->n, matcoloring->ncolors, A->rmap->n, matcoloring->ncolors));
1291:     PetscCall(MatSetType(C_dense, MATSEQDENSE));
1292:     PetscCall(MatSeqDenseSetPreallocation(C_dense, NULL));

1294:     Bt_dense->assembled = PETSC_TRUE;
1295:     abt->ABt_den        = C_dense;

1297: #if defined(PETSC_USE_INFO)
1298:     {
1299:       Mat_SeqAIJ *c = (Mat_SeqAIJ *)C->data;
1300:       PetscCall(PetscInfo(C, "Use coloring of C=A*B^T; B^T: %" PetscInt_FMT " %" PetscInt_FMT ", Bt_dense: %" PetscInt_FMT ",%" PetscInt_FMT "; Cnz %" PetscInt_FMT " / (cm*ncolors %" PetscInt_FMT ") = %g\n", B->cmap->n, B->rmap->n, Bt_dense->rmap->n,
1301:                           Bt_dense->cmap->n, c->nz, A->rmap->n * matcoloring->ncolors, (double)(((PetscReal)c->nz) / ((PetscReal)(A->rmap->n * matcoloring->ncolors)))));
1302:     }
1303: #endif
1304:   }
1305:   /* clean up */
1306:   PetscCall(MatDestroy(&Bt));
1307:   PetscFunctionReturn(PETSC_SUCCESS);
1308: }

1310: PetscErrorCode MatMatTransposeMultNumeric_SeqAIJ_SeqAIJ(Mat A, Mat B, Mat C)
1311: {
1312:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c = (Mat_SeqAIJ *)C->data;
1313:   PetscInt            *ai = a->i, *aj = a->j, *bi = b->i, *bj = b->j, anzi, bnzj, nexta, nextb, *acol, *bcol, brow;
1314:   PetscInt             cm = C->rmap->n, *ci = c->i, *cj = c->j, i, j, cnzi, *ccol;
1315:   PetscLogDouble       flops = 0.0;
1316:   MatScalar           *aa = a->a, *aval, *ba = b->a, *bval, *ca, *cval;
1317:   Mat_MatMatTransMult *abt;
1318:   Mat_Product         *product = C->product;

1320:   PetscFunctionBegin;
1321:   PetscCheck(product, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Missing product struct");
1322:   abt = (Mat_MatMatTransMult *)product->data;
1323:   PetscCheck(abt, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Missing product struct");
1324:   /* clear old values in C */
1325:   if (!c->a) {
1326:     PetscCall(PetscCalloc1(ci[cm] + 1, &ca));
1327:     c->a      = ca;
1328:     c->free_a = PETSC_TRUE;
1329:   } else {
1330:     ca = c->a;
1331:     PetscCall(PetscArrayzero(ca, ci[cm] + 1));
1332:   }

1334:   if (abt->usecoloring) {
1335:     MatTransposeColoring matcoloring = abt->matcoloring;
1336:     Mat                  Bt_dense, C_dense = abt->ABt_den;

1338:     /* Get Bt_dense by Apply MatTransposeColoring to B */
1339:     Bt_dense = abt->Bt_den;
1340:     PetscCall(MatTransColoringApplySpToDen(matcoloring, B, Bt_dense));

1342:     /* C_dense = A*Bt_dense */
1343:     PetscCall(MatMatMultNumeric_SeqAIJ_SeqDense(A, Bt_dense, C_dense));

1345:     /* Recover C from C_dense */
1346:     PetscCall(MatTransColoringApplyDenToSp(matcoloring, C_dense, C));
1347:     PetscFunctionReturn(PETSC_SUCCESS);
1348:   }

1350:   for (i = 0; i < cm; i++) {
1351:     anzi = ai[i + 1] - ai[i];
1352:     acol = PetscSafePointerPlusOffset(aj, ai[i]);
1353:     aval = PetscSafePointerPlusOffset(aa, ai[i]);
1354:     cnzi = ci[i + 1] - ci[i];
1355:     ccol = PetscSafePointerPlusOffset(cj, ci[i]);
1356:     cval = ca + ci[i];
1357:     for (j = 0; j < cnzi; j++) {
1358:       brow = ccol[j];
1359:       bnzj = bi[brow + 1] - bi[brow];
1360:       bcol = bj + bi[brow];
1361:       bval = ba + bi[brow];

1363:       /* perform sparse inner-product c(i,j)=A[i,:]*B[j,:]^T */
1364:       nexta = 0;
1365:       nextb = 0;
1366:       while (nexta < anzi && nextb < bnzj) {
1367:         while (nexta < anzi && acol[nexta] < bcol[nextb]) nexta++;
1368:         if (nexta == anzi) break;
1369:         while (nextb < bnzj && acol[nexta] > bcol[nextb]) nextb++;
1370:         if (nextb == bnzj) break;
1371:         if (acol[nexta] == bcol[nextb]) {
1372:           cval[j] += aval[nexta] * bval[nextb];
1373:           nexta++;
1374:           nextb++;
1375:           flops += 2;
1376:         }
1377:       }
1378:     }
1379:   }
1380:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
1381:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
1382:   PetscCall(PetscLogFlops(flops));
1383:   PetscFunctionReturn(PETSC_SUCCESS);
1384: }

1386: PetscErrorCode MatDestroy_SeqAIJ_MatTransMatMult(void *data)
1387: {
1388:   Mat_MatTransMatMult *atb = (Mat_MatTransMatMult *)data;

1390:   PetscFunctionBegin;
1391:   PetscCall(MatDestroy(&atb->At));
1392:   if (atb->destroy) PetscCall((*atb->destroy)(atb->data));
1393:   PetscCall(PetscFree(atb));
1394:   PetscFunctionReturn(PETSC_SUCCESS);
1395: }

1397: PetscErrorCode MatTransposeMatMultSymbolic_SeqAIJ_SeqAIJ(Mat A, Mat B, PetscReal fill, Mat C)
1398: {
1399:   Mat          At      = NULL;
1400:   Mat_Product *product = C->product;
1401:   PetscBool    flg, def, square;

1403:   PetscFunctionBegin;
1404:   MatCheckProduct(C, 4);
1405:   square = (PetscBool)(A == B && A->symmetric == PETSC_BOOL3_TRUE);
1406:   /* outerproduct */
1407:   PetscCall(PetscStrcmp(product->alg, "outerproduct", &flg));
1408:   if (flg) {
1409:     /* create symbolic At */
1410:     if (!square) {
1411:       PetscCall(MatTransposeSymbolic(A, &At));
1412:       PetscCall(MatSetBlockSizes(At, PetscAbs(A->cmap->bs), PetscAbs(B->cmap->bs)));
1413:       PetscCall(MatSetType(At, ((PetscObject)A)->type_name));
1414:     }
1415:     /* get symbolic C=At*B */
1416:     PetscCall(MatProductSetAlgorithm(C, "sorted"));
1417:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ(square ? A : At, B, fill, C));

1419:     /* clean up */
1420:     if (!square) PetscCall(MatDestroy(&At));

1422:     C->ops->mattransposemultnumeric = MatTransposeMatMultNumeric_SeqAIJ_SeqAIJ; /* outerproduct */
1423:     PetscCall(MatProductSetAlgorithm(C, "outerproduct"));
1424:     PetscFunctionReturn(PETSC_SUCCESS);
1425:   }

1427:   /* matmatmult */
1428:   PetscCall(PetscStrcmp(product->alg, "default", &def));
1429:   PetscCall(PetscStrcmp(product->alg, "at*b", &flg));
1430:   if (flg || def) {
1431:     Mat_MatTransMatMult *atb;

1433:     PetscCheck(!product->data, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Extra product struct not empty");
1434:     PetscCall(PetscNew(&atb));
1435:     if (!square) PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
1436:     PetscCall(MatProductSetAlgorithm(C, "sorted"));
1437:     PetscCall(MatMatMultSymbolic_SeqAIJ_SeqAIJ(square ? A : At, B, fill, C));
1438:     PetscCall(MatProductSetAlgorithm(C, "at*b"));
1439:     product->data    = atb;
1440:     product->destroy = MatDestroy_SeqAIJ_MatTransMatMult;
1441:     atb->At          = At;

1443:     C->ops->mattransposemultnumeric = NULL; /* see MatProductNumeric_AtB_SeqAIJ_SeqAIJ */
1444:     PetscFunctionReturn(PETSC_SUCCESS);
1445:   }

1447:   SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "Mat Product Algorithm is not supported");
1448: }

1450: PetscErrorCode MatTransposeMatMultNumeric_SeqAIJ_SeqAIJ(Mat A, Mat B, Mat C)
1451: {
1452:   Mat_SeqAIJ    *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c = (Mat_SeqAIJ *)C->data;
1453:   PetscInt       am = A->rmap->n, anzi, *ai = a->i, *aj = a->j, *bi = b->i, *bj, bnzi, nextb;
1454:   PetscInt       cm = C->rmap->n, *ci = c->i, *cj = c->j, crow, *cjj, i, j, k;
1455:   PetscLogDouble flops = 0.0;
1456:   MatScalar     *aa    = a->a, *ba, *ca, *caj;

1458:   PetscFunctionBegin;
1459:   if (!c->a) {
1460:     PetscCall(PetscCalloc1(ci[cm] + 1, &ca));

1462:     c->a      = ca;
1463:     c->free_a = PETSC_TRUE;
1464:   } else {
1465:     ca = c->a;
1466:     PetscCall(PetscArrayzero(ca, ci[cm]));
1467:   }

1469:   /* compute A^T*B using outer product (A^T)[:,i]*B[i,:] */
1470:   for (i = 0; i < am; i++) {
1471:     bj   = b->j + bi[i];
1472:     ba   = b->a + bi[i];
1473:     bnzi = bi[i + 1] - bi[i];
1474:     anzi = ai[i + 1] - ai[i];
1475:     for (j = 0; j < anzi; j++) {
1476:       nextb = 0;
1477:       crow  = *aj++;
1478:       cjj   = cj + ci[crow];
1479:       caj   = ca + ci[crow];
1480:       /* perform sparse axpy operation.  Note cjj includes bj. */
1481:       for (k = 0; nextb < bnzi; k++) {
1482:         if (cjj[k] == *(bj + nextb)) { /* ccol == bcol */
1483:           caj[k] += (*aa) * (*(ba + nextb));
1484:           nextb++;
1485:         }
1486:       }
1487:       flops += 2 * bnzi;
1488:       aa++;
1489:     }
1490:   }

1492:   /* Assemble the final matrix and clean up */
1493:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
1494:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
1495:   PetscCall(PetscLogFlops(flops));
1496:   PetscFunctionReturn(PETSC_SUCCESS);
1497: }

1499: PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqDense(Mat A, Mat B, PetscReal fill, Mat C)
1500: {
1501:   PetscFunctionBegin;
1502:   PetscCall(MatMatMultSymbolic_SeqDense_SeqDense(A, B, 0.0, C));
1503:   C->ops->matmultnumeric = MatMatMultNumeric_SeqAIJ_SeqDense;
1504:   PetscFunctionReturn(PETSC_SUCCESS);
1505: }

1507: PETSC_INTERN PetscErrorCode MatMatMultNumericAdd_SeqAIJ_SeqDense(Mat A, Mat B, Mat C, const PetscBool add)
1508: {
1509:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)A->data;
1510:   PetscScalar       *c, r1, r2, r3, r4, *c1, *c2, *c3, *c4;
1511:   const PetscScalar *aa, *b, *b1, *b2, *b3, *b4, *av;
1512:   const PetscInt    *aj;
1513:   PetscInt           cm = C->rmap->n, cn = B->cmap->n, bm, am = A->rmap->n;
1514:   PetscInt           clda;
1515:   PetscInt           am4, bm4, col, i, j, n;

1517:   PetscFunctionBegin;
1518:   if (!cm || !cn) PetscFunctionReturn(PETSC_SUCCESS);
1519:   PetscCall(MatSeqAIJGetArrayRead(A, &av));
1520:   if (add) {
1521:     PetscCall(MatDenseGetArray(C, &c));
1522:   } else {
1523:     PetscCall(MatDenseGetArrayWrite(C, &c));
1524:   }
1525:   PetscCall(MatDenseGetArrayRead(B, &b));
1526:   PetscCall(MatDenseGetLDA(B, &bm));
1527:   PetscCall(MatDenseGetLDA(C, &clda));
1528:   am4 = 4 * clda;
1529:   bm4 = 4 * bm;
1530:   if (b) {
1531:     b1 = b;
1532:     b2 = b1 + bm;
1533:     b3 = b2 + bm;
1534:     b4 = b3 + bm;
1535:   } else b1 = b2 = b3 = b4 = NULL;
1536:   c1 = c;
1537:   c2 = c1 + clda;
1538:   c3 = c2 + clda;
1539:   c4 = c3 + clda;
1540:   for (col = 0; col < (cn / 4) * 4; col += 4) { /* over columns of C */
1541:     for (i = 0; i < am; i++) {                  /* over rows of A in those columns */
1542:       r1 = r2 = r3 = r4 = 0.0;
1543:       n                 = a->i[i + 1] - a->i[i];
1544:       aj                = PetscSafePointerPlusOffset(a->j, a->i[i]);
1545:       aa                = PetscSafePointerPlusOffset(av, a->i[i]);
1546:       for (j = 0; j < n; j++) {
1547:         const PetscScalar aatmp = aa[j];
1548:         const PetscInt    ajtmp = aj[j];
1549:         r1 += aatmp * b1[ajtmp];
1550:         r2 += aatmp * b2[ajtmp];
1551:         r3 += aatmp * b3[ajtmp];
1552:         r4 += aatmp * b4[ajtmp];
1553:       }
1554:       if (add) {
1555:         c1[i] += r1;
1556:         c2[i] += r2;
1557:         c3[i] += r3;
1558:         c4[i] += r4;
1559:       } else {
1560:         c1[i] = r1;
1561:         c2[i] = r2;
1562:         c3[i] = r3;
1563:         c4[i] = r4;
1564:       }
1565:     }
1566:     if (b) {
1567:       b1 += bm4;
1568:       b2 += bm4;
1569:       b3 += bm4;
1570:       b4 += bm4;
1571:     }
1572:     c1 += am4;
1573:     c2 += am4;
1574:     c3 += am4;
1575:     c4 += am4;
1576:   }
1577:   /* process remaining columns */
1578:   if (col != cn) {
1579:     PetscInt rc = cn - col;

1581:     if (rc == 1) {
1582:       for (i = 0; i < am; i++) {
1583:         r1 = 0.0;
1584:         n  = a->i[i + 1] - a->i[i];
1585:         aj = PetscSafePointerPlusOffset(a->j, a->i[i]);
1586:         aa = PetscSafePointerPlusOffset(av, a->i[i]);
1587:         for (j = 0; j < n; j++) r1 += aa[j] * b1[aj[j]];
1588:         if (add) c1[i] += r1;
1589:         else c1[i] = r1;
1590:       }
1591:     } else if (rc == 2) {
1592:       for (i = 0; i < am; i++) {
1593:         r1 = r2 = 0.0;
1594:         n       = a->i[i + 1] - a->i[i];
1595:         aj      = PetscSafePointerPlusOffset(a->j, a->i[i]);
1596:         aa      = PetscSafePointerPlusOffset(av, a->i[i]);
1597:         for (j = 0; j < n; j++) {
1598:           const PetscScalar aatmp = aa[j];
1599:           const PetscInt    ajtmp = aj[j];
1600:           r1 += aatmp * b1[ajtmp];
1601:           r2 += aatmp * b2[ajtmp];
1602:         }
1603:         if (add) {
1604:           c1[i] += r1;
1605:           c2[i] += r2;
1606:         } else {
1607:           c1[i] = r1;
1608:           c2[i] = r2;
1609:         }
1610:       }
1611:     } else {
1612:       for (i = 0; i < am; i++) {
1613:         r1 = r2 = r3 = 0.0;
1614:         n            = a->i[i + 1] - a->i[i];
1615:         aj           = PetscSafePointerPlusOffset(a->j, a->i[i]);
1616:         aa           = PetscSafePointerPlusOffset(av, a->i[i]);
1617:         for (j = 0; j < n; j++) {
1618:           const PetscScalar aatmp = aa[j];
1619:           const PetscInt    ajtmp = aj[j];
1620:           r1 += aatmp * b1[ajtmp];
1621:           r2 += aatmp * b2[ajtmp];
1622:           r3 += aatmp * b3[ajtmp];
1623:         }
1624:         if (add) {
1625:           c1[i] += r1;
1626:           c2[i] += r2;
1627:           c3[i] += r3;
1628:         } else {
1629:           c1[i] = r1;
1630:           c2[i] = r2;
1631:           c3[i] = r3;
1632:         }
1633:       }
1634:     }
1635:   }
1636:   PetscCall(PetscLogFlops(cn * (2.0 * a->nz)));
1637:   if (add) {
1638:     PetscCall(MatDenseRestoreArray(C, &c));
1639:   } else {
1640:     PetscCall(MatDenseRestoreArrayWrite(C, &c));
1641:   }
1642:   PetscCall(MatDenseRestoreArrayRead(B, &b));
1643:   PetscCall(MatSeqAIJRestoreArrayRead(A, &av));
1644:   PetscFunctionReturn(PETSC_SUCCESS);
1645: }

1647: PetscErrorCode MatMatMultNumeric_SeqAIJ_SeqDense(Mat A, Mat B, Mat C)
1648: {
1649:   PetscFunctionBegin;
1650:   PetscCheck(B->rmap->n == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Number columns in A %" PetscInt_FMT " not equal rows in B %" PetscInt_FMT, A->cmap->n, B->rmap->n);
1651:   PetscCheck(A->rmap->n == C->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Number rows in C %" PetscInt_FMT " not equal rows in A %" PetscInt_FMT, C->rmap->n, A->rmap->n);
1652:   PetscCheck(B->cmap->n == C->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Number columns in B %" PetscInt_FMT " not equal columns in C %" PetscInt_FMT, B->cmap->n, C->cmap->n);

1654:   PetscCall(MatMatMultNumericAdd_SeqAIJ_SeqDense(A, B, C, PETSC_FALSE));
1655:   PetscFunctionReturn(PETSC_SUCCESS);
1656: }

1658: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_SeqDense_AB(Mat C)
1659: {
1660:   PetscFunctionBegin;
1661:   C->ops->matmultsymbolic = MatMatMultSymbolic_SeqAIJ_SeqDense;
1662:   C->ops->productsymbolic = MatProductSymbolic_AB;
1663:   PetscFunctionReturn(PETSC_SUCCESS);
1664: }

1666: PETSC_INTERN PetscErrorCode MatTMatTMultSymbolic_SeqAIJ_SeqDense(Mat, Mat, PetscReal, Mat);

1668: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_SeqDense_AtB(Mat C)
1669: {
1670:   PetscFunctionBegin;
1671:   C->ops->transposematmultsymbolic = MatTMatTMultSymbolic_SeqAIJ_SeqDense;
1672:   C->ops->productsymbolic          = MatProductSymbolic_AtB;
1673:   PetscFunctionReturn(PETSC_SUCCESS);
1674: }

1676: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_SeqDense_ABt(Mat C)
1677: {
1678:   PetscFunctionBegin;
1679:   C->ops->mattransposemultsymbolic = MatTMatTMultSymbolic_SeqAIJ_SeqDense;
1680:   C->ops->productsymbolic          = MatProductSymbolic_ABt;
1681:   PetscFunctionReturn(PETSC_SUCCESS);
1682: }

1684: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_SeqAIJ_SeqDense(Mat C)
1685: {
1686:   Mat_Product *product = C->product;

1688:   PetscFunctionBegin;
1689:   switch (product->type) {
1690:   case MATPRODUCT_AB:
1691:     PetscCall(MatProductSetFromOptions_SeqAIJ_SeqDense_AB(C));
1692:     break;
1693:   case MATPRODUCT_AtB:
1694:     PetscCall(MatProductSetFromOptions_SeqAIJ_SeqDense_AtB(C));
1695:     break;
1696:   case MATPRODUCT_ABt:
1697:     PetscCall(MatProductSetFromOptions_SeqAIJ_SeqDense_ABt(C));
1698:     break;
1699:   default:
1700:     break;
1701:   }
1702:   PetscFunctionReturn(PETSC_SUCCESS);
1703: }

1705: static PetscErrorCode MatProductSetFromOptions_SeqXBAIJ_SeqDense_AB(Mat C)
1706: {
1707:   Mat_Product *product = C->product;
1708:   Mat          A       = product->A;
1709:   PetscBool    baij;

1711:   PetscFunctionBegin;
1712:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQBAIJ, &baij));
1713:   if (!baij) { /* A is seqsbaij */
1714:     PetscBool sbaij;
1715:     PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQSBAIJ, &sbaij));
1716:     PetscCheck(sbaij, PetscObjectComm((PetscObject)C), PETSC_ERR_ARG_WRONGSTATE, "Mat must be either seqbaij or seqsbaij format");

1718:     C->ops->matmultsymbolic = MatMatMultSymbolic_SeqSBAIJ_SeqDense;
1719:   } else { /* A is seqbaij */
1720:     C->ops->matmultsymbolic = MatMatMultSymbolic_SeqBAIJ_SeqDense;
1721:   }

1723:   C->ops->productsymbolic = MatProductSymbolic_AB;
1724:   PetscFunctionReturn(PETSC_SUCCESS);
1725: }

1727: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_SeqXBAIJ_SeqDense(Mat C)
1728: {
1729:   Mat_Product *product = C->product;

1731:   PetscFunctionBegin;
1732:   MatCheckProduct(C, 1);
1733:   PetscCheck(product->A, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Missing A");
1734:   if (product->type == MATPRODUCT_AB || (product->type == MATPRODUCT_AtB && product->A->symmetric == PETSC_BOOL3_TRUE)) PetscCall(MatProductSetFromOptions_SeqXBAIJ_SeqDense_AB(C));
1735:   PetscFunctionReturn(PETSC_SUCCESS);
1736: }

1738: static PetscErrorCode MatProductSetFromOptions_SeqDense_SeqAIJ_AB(Mat C)
1739: {
1740:   PetscFunctionBegin;
1741:   C->ops->matmultsymbolic = MatMatMultSymbolic_SeqDense_SeqAIJ;
1742:   C->ops->productsymbolic = MatProductSymbolic_AB;
1743:   PetscFunctionReturn(PETSC_SUCCESS);
1744: }

1746: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_SeqDense_SeqAIJ(Mat C)
1747: {
1748:   Mat_Product *product = C->product;

1750:   PetscFunctionBegin;
1751:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_SeqDense_SeqAIJ_AB(C));
1752:   PetscFunctionReturn(PETSC_SUCCESS);
1753: }

1755: PetscErrorCode MatTransColoringApplySpToDen_SeqAIJ(MatTransposeColoring coloring, Mat B, Mat Btdense)
1756: {
1757:   Mat_SeqAIJ   *b       = (Mat_SeqAIJ *)B->data;
1758:   Mat_SeqDense *btdense = (Mat_SeqDense *)Btdense->data;
1759:   PetscInt     *bi = b->i, *bj = b->j;
1760:   PetscInt      m = Btdense->rmap->n, n = Btdense->cmap->n, j, k, l, col, anz, *btcol, brow, ncolumns;
1761:   MatScalar    *btval, *btval_den, *ba = b->a;
1762:   PetscInt     *columns = coloring->columns, *colorforcol = coloring->colorforcol, ncolors = coloring->ncolors;

1764:   PetscFunctionBegin;
1765:   btval_den = btdense->v;
1766:   PetscCall(PetscArrayzero(btval_den, m * n));
1767:   for (k = 0; k < ncolors; k++) {
1768:     ncolumns = coloring->ncolumns[k];
1769:     for (l = 0; l < ncolumns; l++) { /* insert a row of B to a column of Btdense */
1770:       col   = *(columns + colorforcol[k] + l);
1771:       btcol = bj + bi[col];
1772:       btval = ba + bi[col];
1773:       anz   = bi[col + 1] - bi[col];
1774:       for (j = 0; j < anz; j++) {
1775:         brow            = btcol[j];
1776:         btval_den[brow] = btval[j];
1777:       }
1778:     }
1779:     btval_den += m;
1780:   }
1781:   PetscFunctionReturn(PETSC_SUCCESS);
1782: }

1784: PetscErrorCode MatTransColoringApplyDenToSp_SeqAIJ(MatTransposeColoring matcoloring, Mat Cden, Mat Csp)
1785: {
1786:   Mat_SeqAIJ        *csp = (Mat_SeqAIJ *)Csp->data;
1787:   const PetscScalar *ca_den, *ca_den_ptr;
1788:   PetscScalar       *ca = csp->a;
1789:   PetscInt           k, l, m = Cden->rmap->n, ncolors = matcoloring->ncolors;
1790:   PetscInt           brows = matcoloring->brows, *den2sp = matcoloring->den2sp;
1791:   PetscInt           nrows, *row, *idx;
1792:   PetscInt          *rows = matcoloring->rows, *colorforrow = matcoloring->colorforrow;

1794:   PetscFunctionBegin;
1795:   PetscCall(MatDenseGetArrayRead(Cden, &ca_den));

1797:   if (brows > 0) {
1798:     PetscInt *lstart, row_end, row_start;
1799:     lstart = matcoloring->lstart;
1800:     PetscCall(PetscArrayzero(lstart, ncolors));

1802:     row_end = brows;
1803:     if (row_end > m) row_end = m;
1804:     for (row_start = 0; row_start < m; row_start += brows) { /* loop over row blocks of Csp */
1805:       ca_den_ptr = ca_den;
1806:       for (k = 0; k < ncolors; k++) { /* loop over colors (columns of Cden) */
1807:         nrows = matcoloring->nrows[k];
1808:         row   = rows + colorforrow[k];
1809:         idx   = den2sp + colorforrow[k];
1810:         for (l = lstart[k]; l < nrows; l++) {
1811:           if (row[l] >= row_end) {
1812:             lstart[k] = l;
1813:             break;
1814:           } else {
1815:             ca[idx[l]] = ca_den_ptr[row[l]];
1816:           }
1817:         }
1818:         ca_den_ptr += m;
1819:       }
1820:       row_end += brows;
1821:       if (row_end > m) row_end = m;
1822:     }
1823:   } else { /* non-blocked impl: loop over columns of Csp - slow if Csp is large */
1824:     ca_den_ptr = ca_den;
1825:     for (k = 0; k < ncolors; k++) {
1826:       nrows = matcoloring->nrows[k];
1827:       row   = rows + colorforrow[k];
1828:       idx   = den2sp + colorforrow[k];
1829:       for (l = 0; l < nrows; l++) ca[idx[l]] = ca_den_ptr[row[l]];
1830:       ca_den_ptr += m;
1831:     }
1832:   }

1834:   PetscCall(MatDenseRestoreArrayRead(Cden, &ca_den));
1835: #if defined(PETSC_USE_INFO)
1836:   if (matcoloring->brows > 0) {
1837:     PetscCall(PetscInfo(Csp, "Loop over %" PetscInt_FMT " row blocks for den2sp\n", brows));
1838:   } else {
1839:     PetscCall(PetscInfo(Csp, "Loop over colors/columns of Cden, inefficient for large sparse matrix product \n"));
1840:   }
1841: #endif
1842:   PetscFunctionReturn(PETSC_SUCCESS);
1843: }

1845: PetscErrorCode MatTransposeColoringCreate_SeqAIJ(Mat mat, ISColoring iscoloring, MatTransposeColoring c)
1846: {
1847:   PetscInt        i, n, nrows, Nbs, j, k, m, ncols, col, cm;
1848:   const PetscInt *is, *ci, *cj, *row_idx;
1849:   PetscInt        nis = iscoloring->n, *rowhit, bs = 1;
1850:   IS             *isa;
1851:   Mat_SeqAIJ     *csp = (Mat_SeqAIJ *)mat->data;
1852:   PetscInt       *colorforrow, *rows, *rows_i, *idxhit, *spidx, *den2sp, *den2sp_i;
1853:   PetscInt       *colorforcol, *columns, *columns_i, brows;
1854:   PetscBool       flg;

1856:   PetscFunctionBegin;
1857:   PetscCall(ISColoringGetIS(iscoloring, PETSC_USE_POINTER, PETSC_IGNORE, &isa));

1859:   /* bs >1 is not being tested yet! */
1860:   Nbs       = mat->cmap->N / bs;
1861:   c->M      = mat->rmap->N / bs; /* set total rows, columns and local rows */
1862:   c->N      = Nbs;
1863:   c->m      = c->M;
1864:   c->rstart = 0;
1865:   c->brows  = 100;

1867:   c->ncolors = nis;
1868:   PetscCall(PetscMalloc3(nis, &c->ncolumns, nis, &c->nrows, nis + 1, &colorforrow));
1869:   PetscCall(PetscMalloc1(csp->nz + 1, &rows));
1870:   PetscCall(PetscMalloc1(csp->nz + 1, &den2sp));

1872:   brows = c->brows;
1873:   PetscCall(PetscOptionsGetInt(NULL, NULL, "-matden2sp_brows", &brows, &flg));
1874:   if (flg) c->brows = brows;
1875:   if (brows > 0) PetscCall(PetscMalloc1(nis + 1, &c->lstart));

1877:   colorforrow[0] = 0;
1878:   rows_i         = rows;
1879:   den2sp_i       = den2sp;

1881:   PetscCall(PetscMalloc1(nis + 1, &colorforcol));
1882:   PetscCall(PetscMalloc1(Nbs + 1, &columns));

1884:   colorforcol[0] = 0;
1885:   columns_i      = columns;

1887:   /* get column-wise storage of mat */
1888:   PetscCall(MatGetColumnIJ_SeqAIJ_Color(mat, 0, PETSC_FALSE, PETSC_FALSE, &ncols, &ci, &cj, &spidx, NULL));

1890:   cm = c->m;
1891:   PetscCall(PetscMalloc1(cm + 1, &rowhit));
1892:   PetscCall(PetscMalloc1(cm + 1, &idxhit));
1893:   for (i = 0; i < nis; i++) { /* loop over color */
1894:     PetscCall(ISGetLocalSize(isa[i], &n));
1895:     PetscCall(ISGetIndices(isa[i], &is));

1897:     c->ncolumns[i] = n;
1898:     if (n) PetscCall(PetscArraycpy(columns_i, is, n));
1899:     colorforcol[i + 1] = colorforcol[i] + n;
1900:     columns_i += n;

1902:     /* fast, crude version requires O(N*N) work */
1903:     PetscCall(PetscArrayzero(rowhit, cm));

1905:     for (j = 0; j < n; j++) { /* loop over columns*/
1906:       col     = is[j];
1907:       row_idx = cj + ci[col];
1908:       m       = ci[col + 1] - ci[col];
1909:       for (k = 0; k < m; k++) { /* loop over columns marking them in rowhit */
1910:         idxhit[*row_idx]   = spidx[ci[col] + k];
1911:         rowhit[*row_idx++] = col + 1;
1912:       }
1913:     }
1914:     /* count the number of hits */
1915:     nrows = 0;
1916:     for (j = 0; j < cm; j++) {
1917:       if (rowhit[j]) nrows++;
1918:     }
1919:     c->nrows[i]        = nrows;
1920:     colorforrow[i + 1] = colorforrow[i] + nrows;

1922:     nrows = 0;
1923:     for (j = 0; j < cm; j++) { /* loop over rows */
1924:       if (rowhit[j]) {
1925:         rows_i[nrows]   = j;
1926:         den2sp_i[nrows] = idxhit[j];
1927:         nrows++;
1928:       }
1929:     }
1930:     den2sp_i += nrows;

1932:     PetscCall(ISRestoreIndices(isa[i], &is));
1933:     rows_i += nrows;
1934:   }
1935:   PetscCall(MatRestoreColumnIJ_SeqAIJ_Color(mat, 0, PETSC_FALSE, PETSC_FALSE, &ncols, &ci, &cj, &spidx, NULL));
1936:   PetscCall(PetscFree(rowhit));
1937:   PetscCall(ISColoringRestoreIS(iscoloring, PETSC_USE_POINTER, &isa));
1938:   PetscCheck(csp->nz == colorforrow[nis], PETSC_COMM_SELF, PETSC_ERR_PLIB, "csp->nz %" PetscInt_FMT " != colorforrow[nis] %" PetscInt_FMT, csp->nz, colorforrow[nis]);

1940:   c->colorforrow = colorforrow;
1941:   c->rows        = rows;
1942:   c->den2sp      = den2sp;
1943:   c->colorforcol = colorforcol;
1944:   c->columns     = columns;

1946:   PetscCall(PetscFree(idxhit));
1947:   PetscFunctionReturn(PETSC_SUCCESS);
1948: }

1950: static PetscErrorCode MatProductNumeric_AtB_SeqAIJ_SeqAIJ(Mat C)
1951: {
1952:   Mat_Product *product = C->product;
1953:   Mat          A = product->A, B = product->B;

1955:   PetscFunctionBegin;
1956:   if (C->ops->mattransposemultnumeric) {
1957:     /* Alg: "outerproduct" */
1958:     PetscCall((*C->ops->mattransposemultnumeric)(A, B, C));
1959:   } else {
1960:     /* Alg: "matmatmult" -- C = At*B */
1961:     Mat_MatTransMatMult *atb = (Mat_MatTransMatMult *)product->data;

1963:     PetscCheck(atb, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Missing product struct");
1964:     if (atb->At) {
1965:       /* At is computed in MatTransposeMatMultSymbolic_SeqAIJ_SeqAIJ();
1966:          user may have called MatProductReplaceMats() to get this A=product->A */
1967:       PetscCall(MatTransposeSetPrecursor(A, atb->At));
1968:       PetscCall(MatTranspose(A, MAT_REUSE_MATRIX, &atb->At));
1969:     }
1970:     PetscCall(MatMatMultNumeric_SeqAIJ_SeqAIJ(atb->At ? atb->At : A, B, C));
1971:   }
1972:   PetscFunctionReturn(PETSC_SUCCESS);
1973: }

1975: static PetscErrorCode MatProductSymbolic_AtB_SeqAIJ_SeqAIJ(Mat C)
1976: {
1977:   Mat_Product *product = C->product;
1978:   Mat          A = product->A, B = product->B;
1979:   PetscReal    fill = product->fill;

1981:   PetscFunctionBegin;
1982:   PetscCall(MatTransposeMatMultSymbolic_SeqAIJ_SeqAIJ(A, B, fill, C));

1984:   C->ops->productnumeric = MatProductNumeric_AtB_SeqAIJ_SeqAIJ;
1985:   PetscFunctionReturn(PETSC_SUCCESS);
1986: }

1988: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_AB(Mat C)
1989: {
1990:   Mat_Product *product = C->product;
1991:   PetscInt     alg     = 0; /* default algorithm */
1992:   PetscBool    flg     = PETSC_FALSE;
1993: #if !defined(PETSC_HAVE_HYPRE)
1994:   const char *algTypes[7] = {"sorted", "scalable", "scalable_fast", "heap", "btheap", "llcondensed", "rowmerge"};
1995:   PetscInt    nalg        = 7;
1996: #else
1997:   const char *algTypes[8] = {"sorted", "scalable", "scalable_fast", "heap", "btheap", "llcondensed", "rowmerge", "hypre"};
1998:   PetscInt    nalg        = 8;
1999: #endif

2001:   PetscFunctionBegin;
2002:   /* Set default algorithm */
2003:   PetscCall(PetscStrcmp(C->product->alg, "default", &flg));
2004:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2006:   /* Get runtime option */
2007:   if (product->api_user) {
2008:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
2009:     PetscCall(PetscOptionsEList("-matmatmult_via", "Algorithmic approach", "MatMatMult", algTypes, nalg, algTypes[0], &alg, &flg));
2010:     PetscOptionsEnd();
2011:   } else {
2012:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
2013:     PetscCall(PetscOptionsEList("-mat_product_algorithm", "Algorithmic approach", "MatProduct_AB", algTypes, nalg, algTypes[0], &alg, &flg));
2014:     PetscOptionsEnd();
2015:   }
2016:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2018:   C->ops->productsymbolic = MatProductSymbolic_AB;
2019:   C->ops->matmultsymbolic = MatMatMultSymbolic_SeqAIJ_SeqAIJ;
2020:   PetscFunctionReturn(PETSC_SUCCESS);
2021: }

2023: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_AtB(Mat C)
2024: {
2025:   Mat_Product *product     = C->product;
2026:   PetscInt     alg         = 0; /* default algorithm */
2027:   PetscBool    flg         = PETSC_FALSE;
2028:   const char  *algTypes[3] = {"default", "at*b", "outerproduct"};
2029:   PetscInt     nalg        = 3;

2031:   PetscFunctionBegin;
2032:   /* Get runtime option */
2033:   if (product->api_user) {
2034:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatTransposeMatMult", "Mat");
2035:     PetscCall(PetscOptionsEList("-mattransposematmult_via", "Algorithmic approach", "MatTransposeMatMult", algTypes, nalg, algTypes[alg], &alg, &flg));
2036:     PetscOptionsEnd();
2037:   } else {
2038:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AtB", "Mat");
2039:     PetscCall(PetscOptionsEList("-mat_product_algorithm", "Algorithmic approach", "MatProduct_AtB", algTypes, nalg, algTypes[alg], &alg, &flg));
2040:     PetscOptionsEnd();
2041:   }
2042:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2044:   C->ops->productsymbolic = MatProductSymbolic_AtB_SeqAIJ_SeqAIJ;
2045:   PetscFunctionReturn(PETSC_SUCCESS);
2046: }

2048: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_ABt(Mat C)
2049: {
2050:   Mat_Product *product     = C->product;
2051:   PetscInt     alg         = 0; /* default algorithm */
2052:   PetscBool    flg         = PETSC_FALSE;
2053:   const char  *algTypes[2] = {"default", "color"};
2054:   PetscInt     nalg        = 2;

2056:   PetscFunctionBegin;
2057:   /* Set default algorithm */
2058:   PetscCall(PetscStrcmp(C->product->alg, "default", &flg));
2059:   if (!flg) {
2060:     alg = 1;
2061:     PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));
2062:   }

2064:   /* Get runtime option */
2065:   if (product->api_user) {
2066:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatTransposeMult", "Mat");
2067:     PetscCall(PetscOptionsEList("-matmattransmult_via", "Algorithmic approach", "MatMatTransposeMult", algTypes, nalg, algTypes[alg], &alg, &flg));
2068:     PetscOptionsEnd();
2069:   } else {
2070:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_ABt", "Mat");
2071:     PetscCall(PetscOptionsEList("-mat_product_algorithm", "Algorithmic approach", "MatProduct_ABt", algTypes, nalg, algTypes[alg], &alg, &flg));
2072:     PetscOptionsEnd();
2073:   }
2074:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2076:   C->ops->mattransposemultsymbolic = MatMatTransposeMultSymbolic_SeqAIJ_SeqAIJ;
2077:   C->ops->productsymbolic          = MatProductSymbolic_ABt;
2078:   PetscFunctionReturn(PETSC_SUCCESS);
2079: }

2081: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_PtAP(Mat C)
2082: {
2083:   Mat_Product *product = C->product;
2084:   PetscBool    flg     = PETSC_FALSE;
2085:   PetscInt     alg     = 0; /* default algorithm -- alg=1 should be default!!! */
2086: #if !defined(PETSC_HAVE_HYPRE)
2087:   const char *algTypes[2] = {"scalable", "rap"};
2088:   PetscInt    nalg        = 2;
2089: #else
2090:   const char *algTypes[3] = {"scalable", "rap", "hypre"};
2091:   PetscInt    nalg        = 3;
2092: #endif

2094:   PetscFunctionBegin;
2095:   /* Set default algorithm */
2096:   PetscCall(PetscStrcmp(product->alg, "default", &flg));
2097:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2099:   /* Get runtime option */
2100:   if (product->api_user) {
2101:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
2102:     PetscCall(PetscOptionsEList("-matptap_via", "Algorithmic approach", "MatPtAP", algTypes, nalg, algTypes[0], &alg, &flg));
2103:     PetscOptionsEnd();
2104:   } else {
2105:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
2106:     PetscCall(PetscOptionsEList("-mat_product_algorithm", "Algorithmic approach", "MatProduct_PtAP", algTypes, nalg, algTypes[0], &alg, &flg));
2107:     PetscOptionsEnd();
2108:   }
2109:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2111:   C->ops->productsymbolic = MatProductSymbolic_PtAP_SeqAIJ_SeqAIJ;
2112:   PetscFunctionReturn(PETSC_SUCCESS);
2113: }

2115: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_RARt(Mat C)
2116: {
2117:   Mat_Product *product     = C->product;
2118:   PetscBool    flg         = PETSC_FALSE;
2119:   PetscInt     alg         = 0; /* default algorithm */
2120:   const char  *algTypes[3] = {"r*a*rt", "r*art", "coloring_rart"};
2121:   PetscInt     nalg        = 3;

2123:   PetscFunctionBegin;
2124:   /* Set default algorithm */
2125:   PetscCall(PetscStrcmp(product->alg, "default", &flg));
2126:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2128:   /* Get runtime option */
2129:   if (product->api_user) {
2130:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatRARt", "Mat");
2131:     PetscCall(PetscOptionsEList("-matrart_via", "Algorithmic approach", "MatRARt", algTypes, nalg, algTypes[0], &alg, &flg));
2132:     PetscOptionsEnd();
2133:   } else {
2134:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_RARt", "Mat");
2135:     PetscCall(PetscOptionsEList("-mat_product_algorithm", "Algorithmic approach", "MatProduct_RARt", algTypes, nalg, algTypes[0], &alg, &flg));
2136:     PetscOptionsEnd();
2137:   }
2138:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2140:   C->ops->productsymbolic = MatProductSymbolic_RARt_SeqAIJ_SeqAIJ;
2141:   PetscFunctionReturn(PETSC_SUCCESS);
2142: }

2144: /* ABC = A*B*C = A*(B*C); ABC's algorithm must be chosen from AB's algorithm */
2145: static PetscErrorCode MatProductSetFromOptions_SeqAIJ_ABC(Mat C)
2146: {
2147:   Mat_Product *product     = C->product;
2148:   PetscInt     alg         = 0; /* default algorithm */
2149:   PetscBool    flg         = PETSC_FALSE;
2150:   const char  *algTypes[7] = {"sorted", "scalable", "scalable_fast", "heap", "btheap", "llcondensed", "rowmerge"};
2151:   PetscInt     nalg        = 7;

2153:   PetscFunctionBegin;
2154:   /* Set default algorithm */
2155:   PetscCall(PetscStrcmp(product->alg, "default", &flg));
2156:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2158:   /* Get runtime option */
2159:   if (product->api_user) {
2160:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMatMult", "Mat");
2161:     PetscCall(PetscOptionsEList("-matmatmatmult_via", "Algorithmic approach", "MatMatMatMult", algTypes, nalg, algTypes[alg], &alg, &flg));
2162:     PetscOptionsEnd();
2163:   } else {
2164:     PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_ABC", "Mat");
2165:     PetscCall(PetscOptionsEList("-mat_product_algorithm", "Algorithmic approach", "MatProduct_ABC", algTypes, nalg, algTypes[alg], &alg, &flg));
2166:     PetscOptionsEnd();
2167:   }
2168:   if (flg) PetscCall(MatProductSetAlgorithm(C, (MatProductAlgorithm)algTypes[alg]));

2170:   C->ops->matmatmultsymbolic = MatMatMatMultSymbolic_SeqAIJ_SeqAIJ_SeqAIJ;
2171:   C->ops->productsymbolic    = MatProductSymbolic_ABC;
2172:   PetscFunctionReturn(PETSC_SUCCESS);
2173: }

2175: PetscErrorCode MatProductSetFromOptions_SeqAIJ(Mat C)
2176: {
2177:   Mat_Product *product = C->product;

2179:   PetscFunctionBegin;
2180:   switch (product->type) {
2181:   case MATPRODUCT_AB:
2182:     PetscCall(MatProductSetFromOptions_SeqAIJ_AB(C));
2183:     break;
2184:   case MATPRODUCT_AtB:
2185:     PetscCall(MatProductSetFromOptions_SeqAIJ_AtB(C));
2186:     break;
2187:   case MATPRODUCT_ABt:
2188:     PetscCall(MatProductSetFromOptions_SeqAIJ_ABt(C));
2189:     break;
2190:   case MATPRODUCT_PtAP:
2191:     PetscCall(MatProductSetFromOptions_SeqAIJ_PtAP(C));
2192:     break;
2193:   case MATPRODUCT_RARt:
2194:     PetscCall(MatProductSetFromOptions_SeqAIJ_RARt(C));
2195:     break;
2196:   case MATPRODUCT_ABC:
2197:     PetscCall(MatProductSetFromOptions_SeqAIJ_ABC(C));
2198:     break;
2199:   default:
2200:     break;
2201:   }
2202:   PetscFunctionReturn(PETSC_SUCCESS);
2203: }