xref: /petsc/src/mat/impls/aij/seq/crl/crl.c (revision 609bdbee21ea3be08735c64dbe00a9ab27759925)
1 
2 /*
3   Defines a matrix-vector product for the MATSEQAIJCRL matrix class.
4   This class is derived from the MATSEQAIJ class and retains the
5   compressed row storage (aka Yale sparse matrix format) but augments
6   it with a column oriented storage that is more efficient for
7   matrix vector products on Vector machines.
8 
9   CRL stands for constant row length (that is the same number of columns
10   is kept (padded with zeros) for each row of the sparse matrix.
11 */
12 #include <../src/mat/impls/aij/seq/crl/crl.h>
13 
14 PetscErrorCode MatDestroy_SeqAIJCRL(Mat A)
15 {
16   PetscErrorCode ierr;
17   Mat_AIJCRL     *aijcrl = (Mat_AIJCRL*) A->spptr;
18 
19   /* Free everything in the Mat_AIJCRL data structure. */
20   if (aijcrl) {
21     ierr = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
22   }
23   ierr = PetscFree(A->spptr);CHKERRQ(ierr);
24   ierr = PetscObjectChangeTypeName((PetscObject)A, MATSEQAIJ);CHKERRQ(ierr);
25   ierr = MatDestroy_SeqAIJ(A);CHKERRQ(ierr);
26   PetscFunctionReturn(0);
27 }
28 
29 PetscErrorCode MatDuplicate_AIJCRL(Mat A, MatDuplicateOption op, Mat *M)
30 {
31   PetscFunctionBegin;
32   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Cannot duplicate AIJCRL matrices yet");
33   PetscFunctionReturn(0);
34 }
35 
36 PetscErrorCode MatSeqAIJCRL_create_aijcrl(Mat A)
37 {
38   Mat_SeqAIJ     *a      = (Mat_SeqAIJ*)(A)->data;
39   Mat_AIJCRL     *aijcrl = (Mat_AIJCRL*) A->spptr;
40   PetscInt       m       = A->rmap->n; /* Number of rows in the matrix. */
41   PetscInt       *aj     = a->j; /* From the CSR representation; points to the beginning  of each row. */
42   PetscInt       i, j,rmax = a->rmax,*icols, *ilen = a->ilen;
43   MatScalar      *aa = a->a;
44   PetscScalar    *acols;
45   PetscErrorCode ierr;
46 
47   PetscFunctionBegin;
48   aijcrl->nz   = a->nz;
49   aijcrl->m    = A->rmap->n;
50   aijcrl->rmax = rmax;
51 
52   ierr  = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
53   ierr  = PetscMalloc2(rmax*m,&aijcrl->acols,rmax*m,&aijcrl->icols);CHKERRQ(ierr);
54   acols = aijcrl->acols;
55   icols = aijcrl->icols;
56   for (i=0; i<m; i++) {
57     for (j=0; j<ilen[i]; j++) {
58       acols[j*m+i] = *aa++;
59       icols[j*m+i] = *aj++;
60     }
61     for (; j<rmax; j++) { /* empty column entries */
62       acols[j*m+i] = 0.0;
63       icols[j*m+i] = (j) ? icols[(j-1)*m+i] : 0;  /* handle case where row is EMPTY */
64     }
65   }
66   ierr = PetscInfo2(A,"Percentage of 0's introduced for vectorized multiply %g. Rmax= %D\n",1.0-((double)a->nz)/((double)(rmax*m)),rmax);CHKERRQ(ierr);
67   PetscFunctionReturn(0);
68 }
69 
70 extern PetscErrorCode MatAssemblyEnd_SeqAIJ(Mat,MatAssemblyType);
71 
72 PetscErrorCode MatAssemblyEnd_SeqAIJCRL(Mat A, MatAssemblyType mode)
73 {
74   PetscErrorCode ierr;
75   Mat_SeqAIJ     *a = (Mat_SeqAIJ*)A->data;
76 
77   PetscFunctionBegin;
78   a->inode.use = PETSC_FALSE;
79 
80   ierr = MatAssemblyEnd_SeqAIJ(A,mode);CHKERRQ(ierr);
81   if (mode == MAT_FLUSH_ASSEMBLY) PetscFunctionReturn(0);
82 
83   /* Now calculate the permutation and grouping information. */
84   ierr = MatSeqAIJCRL_create_aijcrl(A);CHKERRQ(ierr);
85   PetscFunctionReturn(0);
86 }
87 
88 #include <../src/mat/impls/aij/seq/crl/ftn-kernels/fmultcrl.h>
89 
90 /*
91     Shared by both sequential and parallel versions of CRL matrix: MATMPIAIJCRL and MATSEQAIJCRL
92     - the scatter is used only in the parallel version
93 
94 */
95 PetscErrorCode MatMult_AIJCRL(Mat A,Vec xx,Vec yy)
96 {
97   Mat_AIJCRL        *aijcrl = (Mat_AIJCRL*) A->spptr;
98   PetscInt          m       = aijcrl->m; /* Number of rows in the matrix. */
99   PetscInt          rmax    = aijcrl->rmax,*icols = aijcrl->icols;
100   PetscScalar       *acols  = aijcrl->acols;
101   PetscErrorCode    ierr;
102   PetscScalar       *y;
103   const PetscScalar *x;
104 #if !defined(PETSC_USE_FORTRAN_KERNEL_MULTCRL)
105   PetscInt          i,j,ii;
106 #endif
107 
108 #if defined(PETSC_HAVE_PRAGMA_DISJOINT)
109 #pragma disjoint(*x,*y,*aa)
110 #endif
111 
112   PetscFunctionBegin;
113   if (aijcrl->xscat) {
114     ierr = VecCopy(xx,aijcrl->xwork);CHKERRQ(ierr);
115     /* get remote values needed for local part of multiply */
116     ierr = VecScatterBegin(aijcrl->xscat,xx,aijcrl->fwork,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
117     ierr = VecScatterEnd(aijcrl->xscat,xx,aijcrl->fwork,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
118     xx   = aijcrl->xwork;
119   }
120 
121   ierr = VecGetArrayRead(xx,&x);CHKERRQ(ierr);
122   ierr = VecGetArray(yy,&y);CHKERRQ(ierr);
123 
124 #if defined(PETSC_USE_FORTRAN_KERNEL_MULTCRL)
125   fortranmultcrl_(&m,&rmax,x,y,icols,acols);
126 #else
127 
128   /* first column */
129   for (j=0; j<m; j++) y[j] = acols[j]*x[icols[j]];
130 
131   /* other columns */
132 #if defined(PETSC_HAVE_CRAY_VECTOR)
133 #pragma _CRI preferstream
134 #endif
135   for (i=1; i<rmax; i++) {
136     ii = i*m;
137 #if defined(PETSC_HAVE_CRAY_VECTOR)
138 #pragma _CRI prefervector
139 #endif
140     for (j=0; j<m; j++) y[j] = y[j] + acols[ii+j]*x[icols[ii+j]];
141   }
142 #if defined(PETSC_HAVE_CRAY_VECTOR)
143 #pragma _CRI ivdep
144 #endif
145 
146 #endif
147   ierr = PetscLogFlops(2.0*aijcrl->nz - m);CHKERRQ(ierr);
148   ierr = VecRestoreArrayRead(xx,&x);CHKERRQ(ierr);
149   ierr = VecRestoreArray(yy,&y);CHKERRQ(ierr);
150   PetscFunctionReturn(0);
151 }
152 
153 
154 /* MatConvert_SeqAIJ_SeqAIJCRL converts a SeqAIJ matrix into a
155  * SeqAIJCRL matrix.  This routine is called by the MatCreate_SeqAIJCRL()
156  * routine, but can also be used to convert an assembled SeqAIJ matrix
157  * into a SeqAIJCRL one. */
158 PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqAIJCRL(Mat A,MatType type,MatReuse reuse,Mat *newmat)
159 {
160   PetscErrorCode ierr;
161   Mat            B = *newmat;
162   Mat_AIJCRL     *aijcrl;
163 
164   PetscFunctionBegin;
165   if (reuse == MAT_INITIAL_MATRIX) {
166     ierr = MatDuplicate(A,MAT_COPY_VALUES,&B);CHKERRQ(ierr);
167   }
168 
169   ierr     = PetscNewLog(B,&aijcrl);CHKERRQ(ierr);
170   B->spptr = (void*) aijcrl;
171 
172   /* Set function pointers for methods that we inherit from AIJ but override. */
173   B->ops->duplicate   = MatDuplicate_AIJCRL;
174   B->ops->assemblyend = MatAssemblyEnd_SeqAIJCRL;
175   B->ops->destroy     = MatDestroy_SeqAIJCRL;
176   B->ops->mult        = MatMult_AIJCRL;
177 
178   /* If A has already been assembled, compute the permutation. */
179   if (A->assembled) {
180     ierr = MatSeqAIJCRL_create_aijcrl(B);CHKERRQ(ierr);
181   }
182   ierr    = PetscObjectChangeTypeName((PetscObject)B,MATSEQAIJCRL);CHKERRQ(ierr);
183   *newmat = B;
184   PetscFunctionReturn(0);
185 }
186 
187 /*@C
188    MatCreateSeqAIJCRL - Creates a sparse matrix of type SEQAIJCRL.
189    This type inherits from AIJ, but stores some additional
190    information that is used to allow better vectorization of
191    the matrix-vector product. At the cost of increased storage, the AIJ formatted
192    matrix can be copied to a format in which pieces of the matrix are
193    stored in ELLPACK format, allowing the vectorized matrix multiply
194    routine to use stride-1 memory accesses.  As with the AIJ type, it is
195    important to preallocate matrix storage in order to get good assembly
196    performance.
197 
198    Collective on MPI_Comm
199 
200    Input Parameters:
201 +  comm - MPI communicator, set to PETSC_COMM_SELF
202 .  m - number of rows
203 .  n - number of columns
204 .  nz - number of nonzeros per row (same for all rows)
205 -  nnz - array containing the number of nonzeros in the various rows
206          (possibly different for each row) or NULL
207 
208    Output Parameter:
209 .  A - the matrix
210 
211    Notes:
212    If nnz is given then nz is ignored
213 
214    Level: intermediate
215 
216 .keywords: matrix, cray, sparse, parallel
217 
218 .seealso: MatCreate(), MatCreateMPIAIJPERM(), MatSetValues()
219 @*/
220 PetscErrorCode  MatCreateSeqAIJCRL(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt nz,const PetscInt nnz[],Mat *A)
221 {
222   PetscErrorCode ierr;
223 
224   PetscFunctionBegin;
225   ierr = MatCreate(comm,A);CHKERRQ(ierr);
226   ierr = MatSetSizes(*A,m,n,m,n);CHKERRQ(ierr);
227   ierr = MatSetType(*A,MATSEQAIJCRL);CHKERRQ(ierr);
228   ierr = MatSeqAIJSetPreallocation_SeqAIJ(*A,nz,nnz);CHKERRQ(ierr);
229   PetscFunctionReturn(0);
230 }
231 
232 PETSC_EXTERN PetscErrorCode MatCreate_SeqAIJCRL(Mat A)
233 {
234   PetscErrorCode ierr;
235 
236   PetscFunctionBegin;
237   ierr = MatSetType(A,MATSEQAIJ);CHKERRQ(ierr);
238   ierr = MatConvert_SeqAIJ_SeqAIJCRL(A,MATSEQAIJCRL,MAT_INPLACE_MATRIX,&A);CHKERRQ(ierr);
239   PetscFunctionReturn(0);
240 }
241 
242 
243