xref: /petsc/src/mat/tests/ex226.c (revision 503c0ea9b45bcfbcebbb1ea5341243bbc69f0bea)
1 static char help[] = "Benchmark for MatMatMult() of AIJ matrices using different 2d finite-difference stencils.\n\n";
2 
3 #include <petscmat.h>
4 
5 /* Converts 3d grid coordinates (i,j,k) for a grid of size m \times n to global indexing. Pass k = 0 for a 2d grid. */
6 int global_index(PetscInt i,PetscInt j,PetscInt k, PetscInt m, PetscInt n) { return i + j * m + k * m * n; }
7 
8 int main(int argc,char **argv)
9 {
10   Mat            A,B,C,PtAP,PtAP_copy,PtAP_squared;
11   PetscInt       i,M,N,Istart,Iend,n=7,j,J,Ii,m=8,k,o=1;
12   PetscScalar    v;
13   PetscBool      equal=PETSC_FALSE,mat_view=PETSC_FALSE;
14   char           stencil[PETSC_MAX_PATH_LEN];
15 #if defined(PETSC_USE_LOG)
16   PetscLogStage  fullMatMatMultStage;
17 #endif
18 
19   PetscCall(PetscInitialize(&argc,&argv,(char*)0,help));
20   PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL));
21   PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
22   PetscCall(PetscOptionsGetInt(NULL,NULL,"-o",&o,NULL));
23   PetscCall(PetscOptionsHasName(NULL,NULL,"-result_view",&mat_view));
24   PetscCall(PetscOptionsGetString(NULL,NULL,"-stencil",stencil,sizeof(stencil),NULL));
25 
26   /* Create a aij matrix A */
27   M    = N = m*n*o;
28   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
29   PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,M,N));
30   PetscCall(MatSetType(A,MATAIJ));
31   PetscCall(MatSetFromOptions(A));
32 
33   /* Consistency checks */
34   PetscCheckFalse(o < 1 || m < 1 || n < 1,PETSC_COMM_WORLD,PETSC_ERR_USER,"Dimensions need to be larger than zero!");
35 
36   /************ 2D stencils ***************/
37   PetscCall(PetscStrcmp(stencil, "2d5point", &equal));
38   if (equal) {   /* 5-point stencil, 2D */
39     PetscCall(MatMPIAIJSetPreallocation(A,5,NULL,5,NULL));
40     PetscCall(MatSeqAIJSetPreallocation(A,5,NULL));
41     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
42     for (Ii=Istart; Ii<Iend; Ii++) {
43       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
44       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
45       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
46       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
47       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
48       v = 4.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
49     }
50   }
51   PetscCall(PetscStrcmp(stencil, "2d9point", &equal));
52   if (equal) {      /* 9-point stencil, 2D */
53     PetscCall(MatMPIAIJSetPreallocation(A,9,NULL,9,NULL));
54     PetscCall(MatSeqAIJSetPreallocation(A,9,NULL));
55     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
56     for (Ii=Istart; Ii<Iend; Ii++) {
57       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
58       if (i>0)            {J = global_index(i-1,j,  k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
59       if (i>0 && j>0)   {J = global_index(i-1,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
60       if (j>0)            {J = global_index(i,  j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
61       if (i<m-1 && j>0)   {J = global_index(i+1,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
62       if (i<m-1)          {J = global_index(i+1,j,  k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
63       if (i<m-1 && j<n-1) {J = global_index(i+1,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
64       if (j<n-1)          {J = global_index(i,  j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
65       if (i>0 && j<n-1) {J = global_index(i-1,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
66       v = 8.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
67     }
68   }
69   PetscCall(PetscStrcmp(stencil, "2d9point2", &equal));
70   if (equal) {      /* 9-point Cartesian stencil (width 2 per coordinate), 2D */
71     PetscCall(MatMPIAIJSetPreallocation(A,9,NULL,9,NULL));
72     PetscCall(MatSeqAIJSetPreallocation(A,9,NULL));
73     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
74     for (Ii=Istart; Ii<Iend; Ii++) {
75       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
76       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
77       if (i>1)   {J = global_index(i-2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
78       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
79       if (i<m-2) {J = global_index(i+2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
80       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
81       if (j>1)   {J = global_index(i,j-2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
82       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
83       if (j<n-2) {J = global_index(i,j+2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
84       v = 8.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
85     }
86   }
87   PetscCall(PetscStrcmp(stencil, "2d13point", &equal));
88   if (equal) {      /* 13-point Cartesian stencil (width 3 per coordinate), 2D */
89     PetscCall(MatMPIAIJSetPreallocation(A,13,NULL,13,NULL));
90     PetscCall(MatSeqAIJSetPreallocation(A,13,NULL));
91     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
92     for (Ii=Istart; Ii<Iend; Ii++) {
93       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
94       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
95       if (i>1)   {J = global_index(i-2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
96       if (i>2)   {J = global_index(i-3,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
97       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
98       if (i<m-2) {J = global_index(i+2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
99       if (i<m-3) {J = global_index(i+3,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
100       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
101       if (j>1)   {J = global_index(i,j-2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
102       if (j>2)   {J = global_index(i,j-3,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
103       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
104       if (j<n-2) {J = global_index(i,j+2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
105       if (j<n-3) {J = global_index(i,j+3,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
106       v = 12.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
107     }
108   }
109   /************ 3D stencils ***************/
110   PetscCall(PetscStrcmp(stencil, "3d7point", &equal));
111   if (equal) {      /* 7-point stencil, 3D */
112     PetscCall(MatMPIAIJSetPreallocation(A,7,NULL,7,NULL));
113     PetscCall(MatSeqAIJSetPreallocation(A,7,NULL));
114     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
115     for (Ii=Istart; Ii<Iend; Ii++) {
116       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
117       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
118       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
119       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
120       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
121       if (k>0)   {J = global_index(i,j,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
122       if (k<o-1) {J = global_index(i,j,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
123       v = 6.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
124     }
125   }
126   PetscCall(PetscStrcmp(stencil, "3d13point", &equal));
127   if (equal) {      /* 13-point stencil, 3D */
128     PetscCall(MatMPIAIJSetPreallocation(A,13,NULL,13,NULL));
129     PetscCall(MatSeqAIJSetPreallocation(A,13,NULL));
130     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
131     for (Ii=Istart; Ii<Iend; Ii++) {
132       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
133       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
134       if (i>1)   {J = global_index(i-2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
135       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
136       if (i<m-2) {J = global_index(i+2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
137       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
138       if (j>1)   {J = global_index(i,j-2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
139       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
140       if (j<n-2) {J = global_index(i,j+2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
141       if (k>0)   {J = global_index(i,j,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
142       if (k>1)   {J = global_index(i,j,k-2,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
143       if (k<o-1) {J = global_index(i,j,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
144       if (k<o-2) {J = global_index(i,j,k+2,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
145       v = 12.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
146     }
147   }
148   PetscCall(PetscStrcmp(stencil, "3d19point", &equal));
149   if (equal) {      /* 19-point stencil, 3D */
150     PetscCall(MatMPIAIJSetPreallocation(A,19,NULL,19,NULL));
151     PetscCall(MatSeqAIJSetPreallocation(A,19,NULL));
152     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
153     for (Ii=Istart; Ii<Iend; Ii++) {
154       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
155       /* one hop */
156       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
157       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
158       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
159       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
160       if (k>0)   {J = global_index(i,j,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
161       if (k<o-1) {J = global_index(i,j,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
162       /* two hops */
163       if (i>0   && j>0)   {J = global_index(i-1,j-1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
164       if (i>0   && k>0)   {J = global_index(i-1,j,  k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
165       if (i>0   && j<n-1) {J = global_index(i-1,j+1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
166       if (i>0   && k<o-1) {J = global_index(i-1,j,  k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
167       if (i<m-1 && j>0)   {J = global_index(i+1,j-1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
168       if (i<m-1 && k>0)   {J = global_index(i+1,j,  k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
169       if (i<m-1 && j<n-1) {J = global_index(i+1,j+1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
170       if (i<m-1 && k<o-1) {J = global_index(i+1,j,  k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
171       if (j>0   && k>0)   {J = global_index(i,  j-1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
172       if (j>0   && k<o-1) {J = global_index(i,  j-1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
173       if (j<n-1 && k>0)   {J = global_index(i,  j+1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
174       if (j<n-1 && k<o-1) {J = global_index(i,  j+1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
175       v = 18.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
176     }
177   }
178   PetscCall(PetscStrcmp(stencil, "3d27point", &equal));
179   if (equal) {      /* 27-point stencil, 3D */
180     PetscCall(MatMPIAIJSetPreallocation(A,27,NULL,27,NULL));
181     PetscCall(MatSeqAIJSetPreallocation(A,27,NULL));
182     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
183     for (Ii=Istart; Ii<Iend; Ii++) {
184       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
185       if (k>0) {
186         if (j>0) {
187           if (i>0)   {J = global_index(i-1,j-1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
188                       J = global_index(i,  j-1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
189           if (i<m-1) {J = global_index(i+1,j-1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
190         }
191         {
192           if (i>0)   {J = global_index(i-1,j,  k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
193                       J = global_index(i,  j,  k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
194           if (i<m-1) {J = global_index(i+1,j,  k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
195         }
196         if (j<n-1) {
197           if (i>0)   {J = global_index(i-1,j+1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
198                       J = global_index(i,  j+1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
199           if (i<m-1) {J = global_index(i+1,j+1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
200         }
201       }
202       {
203         if (j>0) {
204           if (i>0)   {J = global_index(i-1,j-1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
205                       J = global_index(i,  j-1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
206           if (i<m-1) {J = global_index(i+1,j-1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
207         }
208         {
209           if (i>0)   {J = global_index(i-1,j,  k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
210                       J = global_index(i,  j,  k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
211           if (i<m-1) {J = global_index(i+1,j,  k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
212         }
213         if (j<n-1) {
214           if (i>0)   {J = global_index(i-1,j+1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
215                       J = global_index(i,  j+1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
216           if (i<m-1) {J = global_index(i+1,j+1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
217         }
218       }
219       if (k<o-1) {
220         if (j>0) {
221           if (i>0)   {J = global_index(i-1,j-1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
222                       J = global_index(i,  j-1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
223           if (i<m-1) {J = global_index(i+1,j-1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
224         }
225         {
226           if (i>0)   {J = global_index(i-1,j,  k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
227                       J = global_index(i,  j,  k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
228           if (i<m-1) {J = global_index(i+1,j,  k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
229         }
230         if (j<n-1) {
231           if (i>0)   {J = global_index(i-1,j+1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
232                       J = global_index(i,  j+1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
233           if (i<m-1) {J = global_index(i+1,j+1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
234         }
235       }
236       v = 26.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
237     }
238   }
239   PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
240   PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
241 
242   /* Copy A into B in order to have a more representative benchmark (A*A has more cache hits than A*B) */
243   PetscCall(MatDuplicate(A,MAT_COPY_VALUES,&B));
244 
245   PetscCall(PetscLogStageRegister("Full MatMatMult",&fullMatMatMultStage));
246 
247   /* Test C = A*B */
248   PetscCall(PetscLogStagePush(fullMatMatMultStage));
249   PetscCall(MatMatMult(A,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&C));
250 
251   /* Test PtAP_squared = PtAP(C,C)*PtAP(C,C)  */
252   PetscCall(MatPtAP(C,C,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&PtAP));
253   PetscCall(MatDuplicate(PtAP,MAT_COPY_VALUES,&PtAP_copy));
254   PetscCall(MatMatMult(PtAP,PtAP_copy,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&PtAP_squared));
255 
256   PetscCall(MatView(C,PETSC_VIEWER_STDOUT_WORLD));
257   PetscCall(MatView(PtAP_squared,PETSC_VIEWER_STDOUT_WORLD));
258 
259   PetscCall(MatDestroy(&PtAP_squared));
260   PetscCall(MatDestroy(&PtAP_copy));
261   PetscCall(MatDestroy(&PtAP));
262   PetscCall(MatDestroy(&C));
263   PetscCall(MatDestroy(&B));
264   PetscCall(MatDestroy(&A));
265   PetscCall(PetscFinalize());
266   return 0;
267 }
268 
269 /*TEST
270 
271  test:
272       suffix: 1
273       nsize: 1
274       args: -m 8 -n 8 -stencil 2d5point -matmatmult_via sorted
275 
276  test:
277        suffix: 2
278        nsize: 1
279        args: -m 5 -n 5 -o 5 -stencil 3d27point -matmatmult_via rowmerge
280 
281  test:
282       suffix: 3
283       nsize: 4
284       args: -m 6 -n 6 -stencil 2d5point -matmatmult_via seqmpi
285 
286 TEST*/
287