xref: /petsc/src/mat/impls/baij/seq/baijsolvtrannat7.c (revision d2522c19e8fa9bca20aaca277941d9a63e71db6a)
1 #include <../src/mat/impls/baij/seq/baij.h>
2 
3 PetscErrorCode MatSolveTranspose_SeqBAIJ_7_NaturalOrdering_inplace(Mat A, Vec bb, Vec xx) {
4   Mat_SeqBAIJ     *a    = (Mat_SeqBAIJ *)A->data;
5   const PetscInt  *diag = a->diag, n = a->mbs, *vi, *ai = a->i, *aj = a->j;
6   PetscInt         i, nz, idx, idt, oidx;
7   const MatScalar *aa = a->a, *v;
8   PetscScalar      s1, s2, s3, s4, s5, s6, s7, x1, x2, x3, x4, x5, x6, x7, *x;
9 
10   PetscFunctionBegin;
11   PetscCall(VecCopy(bb, xx));
12   PetscCall(VecGetArray(xx, &x));
13 
14   /* forward solve the U^T */
15   idx = 0;
16   for (i = 0; i < n; i++) {
17     v  = aa + 49 * diag[i];
18     /* multiply by the inverse of the block diagonal */
19     x1 = x[idx];
20     x2 = x[1 + idx];
21     x3 = x[2 + idx];
22     x4 = x[3 + idx];
23     x5 = x[4 + idx];
24     x6 = x[5 + idx];
25     x7 = x[6 + idx];
26     s1 = v[0] * x1 + v[1] * x2 + v[2] * x3 + v[3] * x4 + v[4] * x5 + v[5] * x6 + v[6] * x7;
27     s2 = v[7] * x1 + v[8] * x2 + v[9] * x3 + v[10] * x4 + v[11] * x5 + v[12] * x6 + v[13] * x7;
28     s3 = v[14] * x1 + v[15] * x2 + v[16] * x3 + v[17] * x4 + v[18] * x5 + v[19] * x6 + v[20] * x7;
29     s4 = v[21] * x1 + v[22] * x2 + v[23] * x3 + v[24] * x4 + v[25] * x5 + v[26] * x6 + v[27] * x7;
30     s5 = v[28] * x1 + v[29] * x2 + v[30] * x3 + v[31] * x4 + v[32] * x5 + v[33] * x6 + v[34] * x7;
31     s6 = v[35] * x1 + v[36] * x2 + v[37] * x3 + v[38] * x4 + v[39] * x5 + v[40] * x6 + v[41] * x7;
32     s7 = v[42] * x1 + v[43] * x2 + v[44] * x3 + v[45] * x4 + v[46] * x5 + v[47] * x6 + v[48] * x7;
33     v += 49;
34 
35     vi = aj + diag[i] + 1;
36     nz = ai[i + 1] - diag[i] - 1;
37     while (nz--) {
38       oidx = 7 * (*vi++);
39       x[oidx] -= v[0] * s1 + v[1] * s2 + v[2] * s3 + v[3] * s4 + v[4] * s5 + v[5] * s6 + v[6] * s7;
40       x[oidx + 1] -= v[7] * s1 + v[8] * s2 + v[9] * s3 + v[10] * s4 + v[11] * s5 + v[12] * s6 + v[13] * s7;
41       x[oidx + 2] -= v[14] * s1 + v[15] * s2 + v[16] * s3 + v[17] * s4 + v[18] * s5 + v[19] * s6 + v[20] * s7;
42       x[oidx + 3] -= v[21] * s1 + v[22] * s2 + v[23] * s3 + v[24] * s4 + v[25] * s5 + v[26] * s6 + v[27] * s7;
43       x[oidx + 4] -= v[28] * s1 + v[29] * s2 + v[30] * s3 + v[31] * s4 + v[32] * s5 + v[33] * s6 + v[34] * s7;
44       x[oidx + 5] -= v[35] * s1 + v[36] * s2 + v[37] * s3 + v[38] * s4 + v[39] * s5 + v[40] * s6 + v[41] * s7;
45       x[oidx + 6] -= v[42] * s1 + v[43] * s2 + v[44] * s3 + v[45] * s4 + v[46] * s5 + v[47] * s6 + v[48] * s7;
46       v += 49;
47     }
48     x[idx]     = s1;
49     x[1 + idx] = s2;
50     x[2 + idx] = s3;
51     x[3 + idx] = s4;
52     x[4 + idx] = s5;
53     x[5 + idx] = s6;
54     x[6 + idx] = s7;
55     idx += 7;
56   }
57   /* backward solve the L^T */
58   for (i = n - 1; i >= 0; i--) {
59     v   = aa + 49 * diag[i] - 49;
60     vi  = aj + diag[i] - 1;
61     nz  = diag[i] - ai[i];
62     idt = 7 * i;
63     s1  = x[idt];
64     s2  = x[1 + idt];
65     s3  = x[2 + idt];
66     s4  = x[3 + idt];
67     s5  = x[4 + idt];
68     s6  = x[5 + idt];
69     s7  = x[6 + idt];
70     while (nz--) {
71       idx = 7 * (*vi--);
72       x[idx] -= v[0] * s1 + v[1] * s2 + v[2] * s3 + v[3] * s4 + v[4] * s5 + v[5] * s6 + v[6] * s7;
73       x[idx + 1] -= v[7] * s1 + v[8] * s2 + v[9] * s3 + v[10] * s4 + v[11] * s5 + v[12] * s6 + v[13] * s7;
74       x[idx + 2] -= v[14] * s1 + v[15] * s2 + v[16] * s3 + v[17] * s4 + v[18] * s5 + v[19] * s6 + v[20] * s7;
75       x[idx + 3] -= v[21] * s1 + v[22] * s2 + v[23] * s3 + v[24] * s4 + v[25] * s5 + v[26] * s6 + v[27] * s7;
76       x[idx + 4] -= v[28] * s1 + v[29] * s2 + v[30] * s3 + v[31] * s4 + v[32] * s5 + v[33] * s6 + v[34] * s7;
77       x[idx + 5] -= v[35] * s1 + v[36] * s2 + v[37] * s3 + v[38] * s4 + v[39] * s5 + v[40] * s6 + v[41] * s7;
78       x[idx + 6] -= v[42] * s1 + v[43] * s2 + v[44] * s3 + v[45] * s4 + v[46] * s5 + v[47] * s6 + v[48] * s7;
79       v -= 49;
80     }
81   }
82   PetscCall(VecRestoreArray(xx, &x));
83   PetscCall(PetscLogFlops(2.0 * 49 * (a->nz) - 7.0 * A->cmap->n));
84   PetscFunctionReturn(0);
85 }
86 PetscErrorCode MatSolveTranspose_SeqBAIJ_7_NaturalOrdering(Mat A, Vec bb, Vec xx) {
87   Mat_SeqBAIJ     *a = (Mat_SeqBAIJ *)A->data;
88   const PetscInt   n = a->mbs, *vi, *ai = a->i, *aj = a->j, *diag = a->diag;
89   PetscInt         nz, idx, idt, j, i, oidx;
90   const PetscInt   bs = A->rmap->bs, bs2 = a->bs2;
91   const MatScalar *aa = a->a, *v;
92   PetscScalar      s1, s2, s3, s4, s5, s6, s7, x1, x2, x3, x4, x5, x6, x7, *x;
93 
94   PetscFunctionBegin;
95   PetscCall(VecCopy(bb, xx));
96   PetscCall(VecGetArray(xx, &x));
97 
98   /* forward solve the U^T */
99   idx = 0;
100   for (i = 0; i < n; i++) {
101     v  = aa + bs2 * diag[i];
102     /* multiply by the inverse of the block diagonal */
103     x1 = x[idx];
104     x2 = x[1 + idx];
105     x3 = x[2 + idx];
106     x4 = x[3 + idx];
107     x5 = x[4 + idx];
108     x6 = x[5 + idx];
109     x7 = x[6 + idx];
110     s1 = v[0] * x1 + v[1] * x2 + v[2] * x3 + v[3] * x4 + v[4] * x5 + v[5] * x6 + v[6] * x7;
111     s2 = v[7] * x1 + v[8] * x2 + v[9] * x3 + v[10] * x4 + v[11] * x5 + v[12] * x6 + v[13] * x7;
112     s3 = v[14] * x1 + v[15] * x2 + v[16] * x3 + v[17] * x4 + v[18] * x5 + v[19] * x6 + v[20] * x7;
113     s4 = v[21] * x1 + v[22] * x2 + v[23] * x3 + v[24] * x4 + v[25] * x5 + v[26] * x6 + v[27] * x7;
114     s5 = v[28] * x1 + v[29] * x2 + v[30] * x3 + v[31] * x4 + v[32] * x5 + v[33] * x6 + v[34] * x7;
115     s6 = v[35] * x1 + v[36] * x2 + v[37] * x3 + v[38] * x4 + v[39] * x5 + v[40] * x6 + v[41] * x7;
116     s7 = v[42] * x1 + v[43] * x2 + v[44] * x3 + v[45] * x4 + v[46] * x5 + v[47] * x6 + v[48] * x7;
117     v -= bs2;
118     vi = aj + diag[i] - 1;
119     nz = diag[i] - diag[i + 1] - 1;
120     for (j = 0; j > -nz; j--) {
121       oidx = bs * vi[j];
122       x[oidx] -= v[0] * s1 + v[1] * s2 + v[2] * s3 + v[3] * s4 + v[4] * s5 + v[5] * s6 + v[6] * s7;
123       x[oidx + 1] -= v[7] * s1 + v[8] * s2 + v[9] * s3 + v[10] * s4 + v[11] * s5 + v[12] * s6 + v[13] * s7;
124       x[oidx + 2] -= v[14] * s1 + v[15] * s2 + v[16] * s3 + v[17] * s4 + v[18] * s5 + v[19] * s6 + v[20] * s7;
125       x[oidx + 3] -= v[21] * s1 + v[22] * s2 + v[23] * s3 + v[24] * s4 + v[25] * s5 + v[26] * s6 + v[27] * s7;
126       x[oidx + 4] -= v[28] * s1 + v[29] * s2 + v[30] * s3 + v[31] * s4 + v[32] * s5 + v[33] * s6 + v[34] * s7;
127       x[oidx + 5] -= v[35] * s1 + v[36] * s2 + v[37] * s3 + v[38] * s4 + v[39] * s5 + v[40] * s6 + v[41] * s7;
128       x[oidx + 6] -= v[42] * s1 + v[43] * s2 + v[44] * s3 + v[45] * s4 + v[46] * s5 + v[47] * s6 + v[48] * s7;
129       v -= bs2;
130     }
131     x[idx]     = s1;
132     x[1 + idx] = s2;
133     x[2 + idx] = s3;
134     x[3 + idx] = s4;
135     x[4 + idx] = s5;
136     x[5 + idx] = s6;
137     x[6 + idx] = s7;
138     idx += bs;
139   }
140   /* backward solve the L^T */
141   for (i = n - 1; i >= 0; i--) {
142     v   = aa + bs2 * ai[i];
143     vi  = aj + ai[i];
144     nz  = ai[i + 1] - ai[i];
145     idt = bs * i;
146     s1  = x[idt];
147     s2  = x[1 + idt];
148     s3  = x[2 + idt];
149     s4  = x[3 + idt];
150     s5  = x[4 + idt];
151     s6  = x[5 + idt];
152     s7  = x[6 + idt];
153     for (j = 0; j < nz; j++) {
154       idx = bs * vi[j];
155       x[idx] -= v[0] * s1 + v[1] * s2 + v[2] * s3 + v[3] * s4 + v[4] * s5 + v[5] * s6 + v[6] * s7;
156       x[idx + 1] -= v[7] * s1 + v[8] * s2 + v[9] * s3 + v[10] * s4 + v[11] * s5 + v[12] * s6 + v[13] * s7;
157       x[idx + 2] -= v[14] * s1 + v[15] * s2 + v[16] * s3 + v[17] * s4 + v[18] * s5 + v[19] * s6 + v[20] * s7;
158       x[idx + 3] -= v[21] * s1 + v[22] * s2 + v[23] * s3 + v[24] * s4 + v[25] * s5 + v[26] * s6 + v[27] * s7;
159       x[idx + 4] -= v[28] * s1 + v[29] * s2 + v[30] * s3 + v[31] * s4 + v[32] * s5 + v[33] * s6 + v[34] * s7;
160       x[idx + 5] -= v[35] * s1 + v[36] * s2 + v[37] * s3 + v[38] * s4 + v[39] * s5 + v[40] * s6 + v[41] * s7;
161       x[idx + 6] -= v[42] * s1 + v[43] * s2 + v[44] * s3 + v[45] * s4 + v[46] * s5 + v[47] * s6 + v[48] * s7;
162       v += bs2;
163     }
164   }
165   PetscCall(VecRestoreArray(xx, &x));
166   PetscCall(PetscLogFlops(2.0 * bs2 * (a->nz) - bs * A->cmap->n));
167   PetscFunctionReturn(0);
168 }
169