xref: /petsc/src/mat/tests/ex226.c (revision ebead697dbf761eb322f829370bbe90b3bd93fa3)
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   PetscFunctionBeginUser;
20   PetscCall(PetscInitialize(&argc,&argv,(char*)0,help));
21   PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL));
22   PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
23   PetscCall(PetscOptionsGetInt(NULL,NULL,"-o",&o,NULL));
24   PetscCall(PetscOptionsHasName(NULL,NULL,"-result_view",&mat_view));
25   PetscCall(PetscOptionsGetString(NULL,NULL,"-stencil",stencil,sizeof(stencil),NULL));
26 
27   /* Create a aij matrix A */
28   M    = N = m*n*o;
29   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
30   PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,M,N));
31   PetscCall(MatSetType(A,MATAIJ));
32   PetscCall(MatSetFromOptions(A));
33 
34   /* Consistency checks */
35   PetscCheck(o >= 1 && m > 1 && n >= 1,PETSC_COMM_WORLD,PETSC_ERR_USER,"Dimensions need to be larger than zero!");
36 
37   /************ 2D stencils ***************/
38   PetscCall(PetscStrcmp(stencil, "2d5point", &equal));
39   if (equal) {   /* 5-point stencil, 2D */
40     PetscCall(MatMPIAIJSetPreallocation(A,5,NULL,5,NULL));
41     PetscCall(MatSeqAIJSetPreallocation(A,5,NULL));
42     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
43     for (Ii=Istart; Ii<Iend; Ii++) {
44       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
45       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
46       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
47       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
48       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
49       v = 4.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
50     }
51   }
52   PetscCall(PetscStrcmp(stencil, "2d9point", &equal));
53   if (equal) {      /* 9-point stencil, 2D */
54     PetscCall(MatMPIAIJSetPreallocation(A,9,NULL,9,NULL));
55     PetscCall(MatSeqAIJSetPreallocation(A,9,NULL));
56     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
57     for (Ii=Istart; Ii<Iend; Ii++) {
58       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
59       if (i>0)            {J = global_index(i-1,j,  k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
60       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));}
61       if (j>0)            {J = global_index(i,  j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
62       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));}
63       if (i<m-1)          {J = global_index(i+1,j,  k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
64       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));}
65       if (j<n-1)          {J = global_index(i,  j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
66       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));}
67       v = 8.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
68     }
69   }
70   PetscCall(PetscStrcmp(stencil, "2d9point2", &equal));
71   if (equal) {      /* 9-point Cartesian stencil (width 2 per coordinate), 2D */
72     PetscCall(MatMPIAIJSetPreallocation(A,9,NULL,9,NULL));
73     PetscCall(MatSeqAIJSetPreallocation(A,9,NULL));
74     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
75     for (Ii=Istart; Ii<Iend; Ii++) {
76       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
77       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
78       if (i>1)   {J = global_index(i-2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
79       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
80       if (i<m-2) {J = global_index(i+2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
81       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
82       if (j>1)   {J = global_index(i,j-2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
83       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
84       if (j<n-2) {J = global_index(i,j+2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
85       v = 8.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
86     }
87   }
88   PetscCall(PetscStrcmp(stencil, "2d13point", &equal));
89   if (equal) {      /* 13-point Cartesian stencil (width 3 per coordinate), 2D */
90     PetscCall(MatMPIAIJSetPreallocation(A,13,NULL,13,NULL));
91     PetscCall(MatSeqAIJSetPreallocation(A,13,NULL));
92     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
93     for (Ii=Istart; Ii<Iend; Ii++) {
94       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
95       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
96       if (i>1)   {J = global_index(i-2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
97       if (i>2)   {J = global_index(i-3,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
98       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
99       if (i<m-2) {J = global_index(i+2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
100       if (i<m-3) {J = global_index(i+3,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
101       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
102       if (j>1)   {J = global_index(i,j-2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
103       if (j>2)   {J = global_index(i,j-3,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
104       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
105       if (j<n-2) {J = global_index(i,j+2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
106       if (j<n-3) {J = global_index(i,j+3,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
107       v = 12.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
108     }
109   }
110   /************ 3D stencils ***************/
111   PetscCall(PetscStrcmp(stencil, "3d7point", &equal));
112   if (equal) {      /* 7-point stencil, 3D */
113     PetscCall(MatMPIAIJSetPreallocation(A,7,NULL,7,NULL));
114     PetscCall(MatSeqAIJSetPreallocation(A,7,NULL));
115     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
116     for (Ii=Istart; Ii<Iend; Ii++) {
117       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
118       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
119       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
120       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
121       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
122       if (k>0)   {J = global_index(i,j,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
123       if (k<o-1) {J = global_index(i,j,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
124       v = 6.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
125     }
126   }
127   PetscCall(PetscStrcmp(stencil, "3d13point", &equal));
128   if (equal) {      /* 13-point stencil, 3D */
129     PetscCall(MatMPIAIJSetPreallocation(A,13,NULL,13,NULL));
130     PetscCall(MatSeqAIJSetPreallocation(A,13,NULL));
131     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
132     for (Ii=Istart; Ii<Iend; Ii++) {
133       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
134       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
135       if (i>1)   {J = global_index(i-2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
136       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
137       if (i<m-2) {J = global_index(i+2,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
138       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
139       if (j>1)   {J = global_index(i,j-2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
140       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
141       if (j<n-2) {J = global_index(i,j+2,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
142       if (k>0)   {J = global_index(i,j,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
143       if (k>1)   {J = global_index(i,j,k-2,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
144       if (k<o-1) {J = global_index(i,j,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
145       if (k<o-2) {J = global_index(i,j,k+2,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
146       v = 12.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
147     }
148   }
149   PetscCall(PetscStrcmp(stencil, "3d19point", &equal));
150   if (equal) {      /* 19-point stencil, 3D */
151     PetscCall(MatMPIAIJSetPreallocation(A,19,NULL,19,NULL));
152     PetscCall(MatSeqAIJSetPreallocation(A,19,NULL));
153     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
154     for (Ii=Istart; Ii<Iend; Ii++) {
155       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
156       /* one hop */
157       if (i>0)   {J = global_index(i-1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
158       if (i<m-1) {J = global_index(i+1,j,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
159       if (j>0)   {J = global_index(i,j-1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
160       if (j<n-1) {J = global_index(i,j+1,k,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
161       if (k>0)   {J = global_index(i,j,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
162       if (k<o-1) {J = global_index(i,j,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
163       /* two hops */
164       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));}
165       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));}
166       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));}
167       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));}
168       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));}
169       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));}
170       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));}
171       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));}
172       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));}
173       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));}
174       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));}
175       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));}
176       v = 18.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
177     }
178   }
179   PetscCall(PetscStrcmp(stencil, "3d27point", &equal));
180   if (equal) {      /* 27-point stencil, 3D */
181     PetscCall(MatMPIAIJSetPreallocation(A,27,NULL,27,NULL));
182     PetscCall(MatSeqAIJSetPreallocation(A,27,NULL));
183     PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
184     for (Ii=Istart; Ii<Iend; Ii++) {
185       v = -1.0; k = Ii / (m*n); j = (Ii - k * m * n) / m; i = (Ii - k * m * n - j * m);
186       if (k>0) {
187         if (j>0) {
188           if (i>0)   {J = global_index(i-1,j-1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
189                       J = global_index(i,  j-1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
190           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));}
191         }
192         {
193           if (i>0)   {J = global_index(i-1,j,  k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
194                       J = global_index(i,  j,  k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
195           if (i<m-1) {J = global_index(i+1,j,  k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
196         }
197         if (j<n-1) {
198           if (i>0)   {J = global_index(i-1,j+1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
199                       J = global_index(i,  j+1,k-1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
200           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));}
201         }
202       }
203       {
204         if (j>0) {
205           if (i>0)   {J = global_index(i-1,j-1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
206                       J = global_index(i,  j-1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
207           if (i<m-1) {J = global_index(i+1,j-1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
208         }
209         {
210           if (i>0)   {J = global_index(i-1,j,  k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
211                       J = global_index(i,  j,  k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
212           if (i<m-1) {J = global_index(i+1,j,  k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
213         }
214         if (j<n-1) {
215           if (i>0)   {J = global_index(i-1,j+1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
216                       J = global_index(i,  j+1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
217           if (i<m-1) {J = global_index(i+1,j+1,k  ,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
218         }
219       }
220       if (k<o-1) {
221         if (j>0) {
222           if (i>0)   {J = global_index(i-1,j-1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
223                       J = global_index(i,  j-1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
224           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));}
225         }
226         {
227           if (i>0)   {J = global_index(i-1,j,  k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
228                       J = global_index(i,  j,  k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
229           if (i<m-1) {J = global_index(i+1,j,  k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
230         }
231         if (j<n-1) {
232           if (i>0)   {J = global_index(i-1,j+1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));}
233                       J = global_index(i,  j+1,k+1,m,n); PetscCall(MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES));
234           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));}
235         }
236       }
237       v = 26.0; PetscCall(MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES));
238     }
239   }
240   PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
241   PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
242 
243   /* Copy A into B in order to have a more representative benchmark (A*A has more cache hits than A*B) */
244   PetscCall(MatDuplicate(A,MAT_COPY_VALUES,&B));
245 
246   PetscCall(PetscLogStageRegister("Full MatMatMult",&fullMatMatMultStage));
247 
248   /* Test C = A*B */
249   PetscCall(PetscLogStagePush(fullMatMatMultStage));
250   PetscCall(MatMatMult(A,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&C));
251 
252   /* Test PtAP_squared = PtAP(C,C)*PtAP(C,C)  */
253   PetscCall(MatPtAP(C,C,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&PtAP));
254   PetscCall(MatDuplicate(PtAP,MAT_COPY_VALUES,&PtAP_copy));
255   PetscCall(MatMatMult(PtAP,PtAP_copy,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&PtAP_squared));
256 
257   PetscCall(MatView(C,PETSC_VIEWER_STDOUT_WORLD));
258   PetscCall(MatView(PtAP_squared,PETSC_VIEWER_STDOUT_WORLD));
259 
260   PetscCall(MatDestroy(&PtAP_squared));
261   PetscCall(MatDestroy(&PtAP_copy));
262   PetscCall(MatDestroy(&PtAP));
263   PetscCall(MatDestroy(&C));
264   PetscCall(MatDestroy(&B));
265   PetscCall(MatDestroy(&A));
266   PetscCall(PetscFinalize());
267   return 0;
268 }
269 
270 /*TEST
271 
272  test:
273       suffix: 1
274       nsize: 1
275       args: -m 8 -n 8 -stencil 2d5point -matmatmult_via sorted
276 
277  test:
278        suffix: 2
279        nsize: 1
280        args: -m 5 -n 5 -o 5 -stencil 3d27point -matmatmult_via rowmerge
281 
282  test:
283       suffix: 3
284       nsize: 4
285       args: -m 6 -n 6 -stencil 2d5point -matmatmult_via seqmpi
286 
287 TEST*/
288