xref: /petsc/src/mat/impls/baij/seq/baijsolvtrannat7.c (revision 31d78bcd2b98084dc1368b20eb1129c8b9fb39fe)
1 #include <../src/mat/impls/baij/seq/baij.h>
2 
MatSolveTranspose_SeqBAIJ_7_NaturalOrdering_inplace(Mat A,Vec bb,Vec xx)3 PetscErrorCode MatSolveTranspose_SeqBAIJ_7_NaturalOrdering_inplace(Mat A, Vec bb, Vec xx)
4 {
5   Mat_SeqBAIJ     *a    = (Mat_SeqBAIJ *)A->data;
6   const PetscInt  *diag = a->diag, n = a->mbs, *vi, *ai = a->i, *aj = a->j;
7   PetscInt         i, nz, idx, idt, oidx;
8   const MatScalar *aa = a->a, *v;
9   PetscScalar      s1, s2, s3, s4, s5, s6, s7, x1, x2, x3, x4, x5, x6, x7, *x;
10 
11   PetscFunctionBegin;
12   PetscCall(VecCopy(bb, xx));
13   PetscCall(VecGetArray(xx, &x));
14 
15   /* forward solve the U^T */
16   idx = 0;
17   for (i = 0; i < n; i++) {
18     v = aa + 49 * diag[i];
19     /* multiply by the inverse of the block diagonal */
20     x1 = x[idx];
21     x2 = x[1 + idx];
22     x3 = x[2 + idx];
23     x4 = x[3 + idx];
24     x5 = x[4 + idx];
25     x6 = x[5 + idx];
26     x7 = x[6 + idx];
27     s1 = v[0] * x1 + v[1] * x2 + v[2] * x3 + v[3] * x4 + v[4] * x5 + v[5] * x6 + v[6] * x7;
28     s2 = v[7] * x1 + v[8] * x2 + v[9] * x3 + v[10] * x4 + v[11] * x5 + v[12] * x6 + v[13] * x7;
29     s3 = v[14] * x1 + v[15] * x2 + v[16] * x3 + v[17] * x4 + v[18] * x5 + v[19] * x6 + v[20] * x7;
30     s4 = v[21] * x1 + v[22] * x2 + v[23] * x3 + v[24] * x4 + v[25] * x5 + v[26] * x6 + v[27] * x7;
31     s5 = v[28] * x1 + v[29] * x2 + v[30] * x3 + v[31] * x4 + v[32] * x5 + v[33] * x6 + v[34] * x7;
32     s6 = v[35] * x1 + v[36] * x2 + v[37] * x3 + v[38] * x4 + v[39] * x5 + v[40] * x6 + v[41] * x7;
33     s7 = v[42] * x1 + v[43] * x2 + v[44] * x3 + v[45] * x4 + v[46] * x5 + v[47] * x6 + v[48] * x7;
34     v += 49;
35 
36     vi = aj + diag[i] + 1;
37     nz = ai[i + 1] - diag[i] - 1;
38     while (nz--) {
39       oidx = 7 * (*vi++);
40       x[oidx] -= v[0] * s1 + v[1] * s2 + v[2] * s3 + v[3] * s4 + v[4] * s5 + v[5] * s6 + v[6] * s7;
41       x[oidx + 1] -= v[7] * s1 + v[8] * s2 + v[9] * s3 + v[10] * s4 + v[11] * s5 + v[12] * s6 + v[13] * s7;
42       x[oidx + 2] -= v[14] * s1 + v[15] * s2 + v[16] * s3 + v[17] * s4 + v[18] * s5 + v[19] * s6 + v[20] * s7;
43       x[oidx + 3] -= v[21] * s1 + v[22] * s2 + v[23] * s3 + v[24] * s4 + v[25] * s5 + v[26] * s6 + v[27] * s7;
44       x[oidx + 4] -= v[28] * s1 + v[29] * s2 + v[30] * s3 + v[31] * s4 + v[32] * s5 + v[33] * s6 + v[34] * s7;
45       x[oidx + 5] -= v[35] * s1 + v[36] * s2 + v[37] * s3 + v[38] * s4 + v[39] * s5 + v[40] * s6 + v[41] * s7;
46       x[oidx + 6] -= v[42] * s1 + v[43] * s2 + v[44] * s3 + v[45] * s4 + v[46] * s5 + v[47] * s6 + v[48] * s7;
47       v += 49;
48     }
49     x[idx]     = s1;
50     x[1 + idx] = s2;
51     x[2 + idx] = s3;
52     x[3 + idx] = s4;
53     x[4 + idx] = s5;
54     x[5 + idx] = s6;
55     x[6 + idx] = s7;
56     idx += 7;
57   }
58   /* backward solve the L^T */
59   for (i = n - 1; i >= 0; i--) {
60     v   = aa + 49 * diag[i] - 49;
61     vi  = aj + diag[i] - 1;
62     nz  = diag[i] - ai[i];
63     idt = 7 * i;
64     s1  = x[idt];
65     s2  = x[1 + idt];
66     s3  = x[2 + idt];
67     s4  = x[3 + idt];
68     s5  = x[4 + idt];
69     s6  = x[5 + idt];
70     s7  = x[6 + idt];
71     while (nz--) {
72       idx = 7 * (*vi--);
73       x[idx] -= v[0] * s1 + v[1] * s2 + v[2] * s3 + v[3] * s4 + v[4] * s5 + v[5] * s6 + v[6] * s7;
74       x[idx + 1] -= v[7] * s1 + v[8] * s2 + v[9] * s3 + v[10] * s4 + v[11] * s5 + v[12] * s6 + v[13] * s7;
75       x[idx + 2] -= v[14] * s1 + v[15] * s2 + v[16] * s3 + v[17] * s4 + v[18] * s5 + v[19] * s6 + v[20] * s7;
76       x[idx + 3] -= v[21] * s1 + v[22] * s2 + v[23] * s3 + v[24] * s4 + v[25] * s5 + v[26] * s6 + v[27] * s7;
77       x[idx + 4] -= v[28] * s1 + v[29] * s2 + v[30] * s3 + v[31] * s4 + v[32] * s5 + v[33] * s6 + v[34] * s7;
78       x[idx + 5] -= v[35] * s1 + v[36] * s2 + v[37] * s3 + v[38] * s4 + v[39] * s5 + v[40] * s6 + v[41] * s7;
79       x[idx + 6] -= v[42] * s1 + v[43] * s2 + v[44] * s3 + v[45] * s4 + v[46] * s5 + v[47] * s6 + v[48] * s7;
80       v -= 49;
81     }
82   }
83   PetscCall(VecRestoreArray(xx, &x));
84   PetscCall(PetscLogFlops(2.0 * 49 * (a->nz) - 7.0 * A->cmap->n));
85   PetscFunctionReturn(PETSC_SUCCESS);
86 }
MatSolveTranspose_SeqBAIJ_7_NaturalOrdering(Mat A,Vec bb,Vec xx)87 PetscErrorCode MatSolveTranspose_SeqBAIJ_7_NaturalOrdering(Mat A, Vec bb, Vec xx)
88 {
89   Mat_SeqBAIJ     *a = (Mat_SeqBAIJ *)A->data;
90   const PetscInt   n = a->mbs, *vi, *ai = a->i, *aj = a->j, *diag = a->diag;
91   PetscInt         nz, idx, idt, j, i, oidx;
92   const PetscInt   bs = A->rmap->bs, bs2 = a->bs2;
93   const MatScalar *aa = a->a, *v;
94   PetscScalar      s1, s2, s3, s4, s5, s6, s7, x1, x2, x3, x4, x5, x6, x7, *x;
95 
96   PetscFunctionBegin;
97   PetscCall(VecCopy(bb, xx));
98   PetscCall(VecGetArray(xx, &x));
99 
100   /* forward solve the U^T */
101   idx = 0;
102   for (i = 0; i < n; i++) {
103     v = aa + bs2 * diag[i];
104     /* multiply by the inverse of the block diagonal */
105     x1 = x[idx];
106     x2 = x[1 + idx];
107     x3 = x[2 + idx];
108     x4 = x[3 + idx];
109     x5 = x[4 + idx];
110     x6 = x[5 + idx];
111     x7 = x[6 + idx];
112     s1 = v[0] * x1 + v[1] * x2 + v[2] * x3 + v[3] * x4 + v[4] * x5 + v[5] * x6 + v[6] * x7;
113     s2 = v[7] * x1 + v[8] * x2 + v[9] * x3 + v[10] * x4 + v[11] * x5 + v[12] * x6 + v[13] * x7;
114     s3 = v[14] * x1 + v[15] * x2 + v[16] * x3 + v[17] * x4 + v[18] * x5 + v[19] * x6 + v[20] * x7;
115     s4 = v[21] * x1 + v[22] * x2 + v[23] * x3 + v[24] * x4 + v[25] * x5 + v[26] * x6 + v[27] * x7;
116     s5 = v[28] * x1 + v[29] * x2 + v[30] * x3 + v[31] * x4 + v[32] * x5 + v[33] * x6 + v[34] * x7;
117     s6 = v[35] * x1 + v[36] * x2 + v[37] * x3 + v[38] * x4 + v[39] * x5 + v[40] * x6 + v[41] * x7;
118     s7 = v[42] * x1 + v[43] * x2 + v[44] * x3 + v[45] * x4 + v[46] * x5 + v[47] * x6 + v[48] * x7;
119     v -= bs2;
120     vi = aj + diag[i] - 1;
121     nz = diag[i] - diag[i + 1] - 1;
122     for (j = 0; j > -nz; j--) {
123       oidx = bs * vi[j];
124       x[oidx] -= v[0] * s1 + v[1] * s2 + v[2] * s3 + v[3] * s4 + v[4] * s5 + v[5] * s6 + v[6] * s7;
125       x[oidx + 1] -= v[7] * s1 + v[8] * s2 + v[9] * s3 + v[10] * s4 + v[11] * s5 + v[12] * s6 + v[13] * s7;
126       x[oidx + 2] -= v[14] * s1 + v[15] * s2 + v[16] * s3 + v[17] * s4 + v[18] * s5 + v[19] * s6 + v[20] * s7;
127       x[oidx + 3] -= v[21] * s1 + v[22] * s2 + v[23] * s3 + v[24] * s4 + v[25] * s5 + v[26] * s6 + v[27] * s7;
128       x[oidx + 4] -= v[28] * s1 + v[29] * s2 + v[30] * s3 + v[31] * s4 + v[32] * s5 + v[33] * s6 + v[34] * s7;
129       x[oidx + 5] -= v[35] * s1 + v[36] * s2 + v[37] * s3 + v[38] * s4 + v[39] * s5 + v[40] * s6 + v[41] * s7;
130       x[oidx + 6] -= v[42] * s1 + v[43] * s2 + v[44] * s3 + v[45] * s4 + v[46] * s5 + v[47] * s6 + v[48] * s7;
131       v -= bs2;
132     }
133     x[idx]     = s1;
134     x[1 + idx] = s2;
135     x[2 + idx] = s3;
136     x[3 + idx] = s4;
137     x[4 + idx] = s5;
138     x[5 + idx] = s6;
139     x[6 + idx] = s7;
140     idx += bs;
141   }
142   /* backward solve the L^T */
143   for (i = n - 1; i >= 0; i--) {
144     v   = aa + bs2 * ai[i];
145     vi  = aj + ai[i];
146     nz  = ai[i + 1] - ai[i];
147     idt = bs * i;
148     s1  = x[idt];
149     s2  = x[1 + idt];
150     s3  = x[2 + idt];
151     s4  = x[3 + idt];
152     s5  = x[4 + idt];
153     s6  = x[5 + idt];
154     s7  = x[6 + idt];
155     for (j = 0; j < nz; j++) {
156       idx = bs * vi[j];
157       x[idx] -= v[0] * s1 + v[1] * s2 + v[2] * s3 + v[3] * s4 + v[4] * s5 + v[5] * s6 + v[6] * s7;
158       x[idx + 1] -= v[7] * s1 + v[8] * s2 + v[9] * s3 + v[10] * s4 + v[11] * s5 + v[12] * s6 + v[13] * s7;
159       x[idx + 2] -= v[14] * s1 + v[15] * s2 + v[16] * s3 + v[17] * s4 + v[18] * s5 + v[19] * s6 + v[20] * s7;
160       x[idx + 3] -= v[21] * s1 + v[22] * s2 + v[23] * s3 + v[24] * s4 + v[25] * s5 + v[26] * s6 + v[27] * s7;
161       x[idx + 4] -= v[28] * s1 + v[29] * s2 + v[30] * s3 + v[31] * s4 + v[32] * s5 + v[33] * s6 + v[34] * s7;
162       x[idx + 5] -= v[35] * s1 + v[36] * s2 + v[37] * s3 + v[38] * s4 + v[39] * s5 + v[40] * s6 + v[41] * s7;
163       x[idx + 6] -= v[42] * s1 + v[43] * s2 + v[44] * s3 + v[45] * s4 + v[46] * s5 + v[47] * s6 + v[48] * s7;
164       v += bs2;
165     }
166   }
167   PetscCall(VecRestoreArray(xx, &x));
168   PetscCall(PetscLogFlops(2.0 * bs2 * (a->nz) - bs * A->cmap->n));
169   PetscFunctionReturn(PETSC_SUCCESS);
170 }
171