xref: /petsc/src/mat/impls/aij/seq/crl/crl.c (revision ccb4e88a40f0b86eaeca07ff64c64e4de2fae686)
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   PetscFunctionBegin;
20   /* Free everything in the Mat_AIJCRL data structure. */
21   if (aijcrl) {
22     ierr = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
23   }
24   ierr = PetscFree(A->spptr);CHKERRQ(ierr);
25   ierr = PetscObjectChangeTypeName((PetscObject)A, MATSEQAIJ);CHKERRQ(ierr);
26   ierr = MatDestroy_SeqAIJ(A);CHKERRQ(ierr);
27   PetscFunctionReturn(0);
28 }
29 
30 PetscErrorCode MatDuplicate_AIJCRL(Mat A, MatDuplicateOption op, Mat *M)
31 {
32   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Cannot duplicate AIJCRL matrices yet");
33 }
34 
35 PetscErrorCode MatSeqAIJCRL_create_aijcrl(Mat A)
36 {
37   Mat_SeqAIJ     *a      = (Mat_SeqAIJ*)(A)->data;
38   Mat_AIJCRL     *aijcrl = (Mat_AIJCRL*) A->spptr;
39   PetscInt       m       = A->rmap->n; /* Number of rows in the matrix. */
40   PetscInt       *aj     = a->j; /* From the CSR representation; points to the beginning  of each row. */
41   PetscInt       i, j,rmax = a->rmax,*icols, *ilen = a->ilen;
42   MatScalar      *aa = a->a;
43   PetscScalar    *acols;
44   PetscErrorCode ierr;
45 
46   PetscFunctionBegin;
47   aijcrl->nz   = a->nz;
48   aijcrl->m    = A->rmap->n;
49   aijcrl->rmax = rmax;
50 
51   ierr  = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
52   ierr  = PetscMalloc2(rmax*m,&aijcrl->acols,rmax*m,&aijcrl->icols);CHKERRQ(ierr);
53   acols = aijcrl->acols;
54   icols = aijcrl->icols;
55   for (i=0; i<m; i++) {
56     for (j=0; j<ilen[i]; j++) {
57       acols[j*m+i] = *aa++;
58       icols[j*m+i] = *aj++;
59     }
60     for (; j<rmax; j++) { /* empty column entries */
61       acols[j*m+i] = 0.0;
62       icols[j*m+i] = (j) ? icols[(j-1)*m+i] : 0;  /* handle case where row is EMPTY */
63     }
64   }
65   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);
66   PetscFunctionReturn(0);
67 }
68 
69 PetscErrorCode MatAssemblyEnd_SeqAIJCRL(Mat A, MatAssemblyType mode)
70 {
71   PetscErrorCode ierr;
72   Mat_SeqAIJ     *a = (Mat_SeqAIJ*)A->data;
73 
74   PetscFunctionBegin;
75   a->inode.use = PETSC_FALSE;
76 
77   ierr = MatAssemblyEnd_SeqAIJ(A,mode);CHKERRQ(ierr);
78   if (mode == MAT_FLUSH_ASSEMBLY) PetscFunctionReturn(0);
79 
80   /* Now calculate the permutation and grouping information. */
81   ierr = MatSeqAIJCRL_create_aijcrl(A);CHKERRQ(ierr);
82   PetscFunctionReturn(0);
83 }
84 
85 #include <../src/mat/impls/aij/seq/crl/ftn-kernels/fmultcrl.h>
86 
87 /*
88     Shared by both sequential and parallel versions of CRL matrix: MATMPIAIJCRL and MATSEQAIJCRL
89     - the scatter is used only in the parallel version
90 
91 */
92 PetscErrorCode MatMult_AIJCRL(Mat A,Vec xx,Vec yy)
93 {
94   Mat_AIJCRL        *aijcrl = (Mat_AIJCRL*) A->spptr;
95   PetscInt          m       = aijcrl->m; /* Number of rows in the matrix. */
96   PetscInt          rmax    = aijcrl->rmax,*icols = aijcrl->icols;
97   PetscScalar       *acols  = aijcrl->acols;
98   PetscErrorCode    ierr;
99   PetscScalar       *y;
100   const PetscScalar *x;
101 #if !defined(PETSC_USE_FORTRAN_KERNEL_MULTCRL)
102   PetscInt          i,j,ii;
103 #endif
104 
105 #if defined(PETSC_HAVE_PRAGMA_DISJOINT)
106 #pragma disjoint(*x,*y,*aa)
107 #endif
108 
109   PetscFunctionBegin;
110   if (aijcrl->xscat) {
111     ierr = VecCopy(xx,aijcrl->xwork);CHKERRQ(ierr);
112     /* get remote values needed for local part of multiply */
113     ierr = VecScatterBegin(aijcrl->xscat,xx,aijcrl->fwork,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
114     ierr = VecScatterEnd(aijcrl->xscat,xx,aijcrl->fwork,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
115     xx   = aijcrl->xwork;
116   }
117 
118   ierr = VecGetArrayRead(xx,&x);CHKERRQ(ierr);
119   ierr = VecGetArray(yy,&y);CHKERRQ(ierr);
120 
121 #if defined(PETSC_USE_FORTRAN_KERNEL_MULTCRL)
122   fortranmultcrl_(&m,&rmax,x,y,icols,acols);
123 #else
124 
125   /* first column */
126   for (j=0; j<m; j++) y[j] = acols[j]*x[icols[j]];
127 
128   /* other columns */
129 #if defined(PETSC_HAVE_CRAY_VECTOR)
130 #pragma _CRI preferstream
131 #endif
132   for (i=1; i<rmax; i++) {
133     ii = i*m;
134 #if defined(PETSC_HAVE_CRAY_VECTOR)
135 #pragma _CRI prefervector
136 #endif
137     for (j=0; j<m; j++) y[j] = y[j] + acols[ii+j]*x[icols[ii+j]];
138   }
139 #if defined(PETSC_HAVE_CRAY_VECTOR)
140 #pragma _CRI ivdep
141 #endif
142 
143 #endif
144   ierr = PetscLogFlops(2.0*aijcrl->nz - m);CHKERRQ(ierr);
145   ierr = VecRestoreArrayRead(xx,&x);CHKERRQ(ierr);
146   ierr = VecRestoreArray(yy,&y);CHKERRQ(ierr);
147   PetscFunctionReturn(0);
148 }
149 
150 /* MatConvert_SeqAIJ_SeqAIJCRL converts a SeqAIJ matrix into a
151  * SeqAIJCRL matrix.  This routine is called by the MatCreate_SeqAIJCRL()
152  * routine, but can also be used to convert an assembled SeqAIJ matrix
153  * into a SeqAIJCRL one. */
154 PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqAIJCRL(Mat A,MatType type,MatReuse reuse,Mat *newmat)
155 {
156   PetscErrorCode ierr;
157   Mat            B = *newmat;
158   Mat_AIJCRL     *aijcrl;
159   PetscBool      sametype;
160 
161   PetscFunctionBegin;
162   if (reuse == MAT_INITIAL_MATRIX) {
163     ierr = MatDuplicate(A,MAT_COPY_VALUES,&B);CHKERRQ(ierr);
164   }
165   ierr = PetscObjectTypeCompare((PetscObject)A,type,&sametype);CHKERRQ(ierr);
166   if (sametype) PetscFunctionReturn(0);
167 
168   ierr     = PetscNewLog(B,&aijcrl);CHKERRQ(ierr);
169   B->spptr = (void*) aijcrl;
170 
171   /* Set function pointers for methods that we inherit from AIJ but override. */
172   B->ops->duplicate   = MatDuplicate_AIJCRL;
173   B->ops->assemblyend = MatAssemblyEnd_SeqAIJCRL;
174   B->ops->destroy     = MatDestroy_SeqAIJCRL;
175   B->ops->mult        = MatMult_AIJCRL;
176 
177   /* If A has already been assembled, compute the permutation. */
178   if (A->assembled) {
179     ierr = MatSeqAIJCRL_create_aijcrl(B);CHKERRQ(ierr);
180   }
181   ierr    = PetscObjectChangeTypeName((PetscObject)B,MATSEQAIJCRL);CHKERRQ(ierr);
182   *newmat = B;
183   PetscFunctionReturn(0);
184 }
185 
186 /*@C
187    MatCreateSeqAIJCRL - Creates a sparse matrix of type SEQAIJCRL.
188    This type inherits from AIJ, but stores some additional
189    information that is used to allow better vectorization of
190    the matrix-vector product. At the cost of increased storage, the AIJ formatted
191    matrix can be copied to a format in which pieces of the matrix are
192    stored in ELLPACK format, allowing the vectorized matrix multiply
193    routine to use stride-1 memory accesses.  As with the AIJ type, it is
194    important to preallocate matrix storage in order to get good assembly
195    performance.
196 
197    Collective
198 
199    Input Parameters:
200 +  comm - MPI communicator, set to PETSC_COMM_SELF
201 .  m - number of rows
202 .  n - number of columns
203 .  nz - number of nonzeros per row (same for all rows)
204 -  nnz - array containing the number of nonzeros in the various rows
205          (possibly different for each row) or NULL
206 
207    Output Parameter:
208 .  A - the matrix
209 
210    Notes:
211    If nnz is given then nz is ignored
212 
213    Level: intermediate
214 
215 .seealso: MatCreate(), MatCreateMPIAIJPERM(), MatSetValues()
216 @*/
217 PetscErrorCode  MatCreateSeqAIJCRL(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt nz,const PetscInt nnz[],Mat *A)
218 {
219   PetscErrorCode ierr;
220 
221   PetscFunctionBegin;
222   ierr = MatCreate(comm,A);CHKERRQ(ierr);
223   ierr = MatSetSizes(*A,m,n,m,n);CHKERRQ(ierr);
224   ierr = MatSetType(*A,MATSEQAIJCRL);CHKERRQ(ierr);
225   ierr = MatSeqAIJSetPreallocation_SeqAIJ(*A,nz,nnz);CHKERRQ(ierr);
226   PetscFunctionReturn(0);
227 }
228 
229 PETSC_EXTERN PetscErrorCode MatCreate_SeqAIJCRL(Mat A)
230 {
231   PetscErrorCode ierr;
232 
233   PetscFunctionBegin;
234   ierr = MatSetType(A,MATSEQAIJ);CHKERRQ(ierr);
235   ierr = MatConvert_SeqAIJ_SeqAIJCRL(A,MATSEQAIJCRL,MAT_INPLACE_MATRIX,&A);CHKERRQ(ierr);
236   PetscFunctionReturn(0);
237 }
238 
239