Actual source code: baijsolvtrann.c
1: #include <../src/mat/impls/baij/seq/baij.h>
2: #include <petsc/private/kernels/blockinvert.h>
4: PetscErrorCode MatSolveTranspose_SeqBAIJ_N_inplace(Mat A, Vec bb, Vec xx)
5: {
6: Mat_SeqBAIJ *a = (Mat_SeqBAIJ *)A->data;
7: IS iscol = a->col, isrow = a->row;
8: const PetscInt *r, *c, *rout, *cout, *ai = a->i, *aj = a->j, *vi;
9: PetscInt i, nz, j;
10: const PetscInt n = a->mbs, bs = A->rmap->bs, bs2 = a->bs2;
11: const MatScalar *aa = a->a, *v;
12: PetscScalar *x, *t, *ls;
13: const PetscScalar *b;
15: PetscFunctionBegin;
16: PetscCall(VecGetArrayRead(bb, &b));
17: PetscCall(VecGetArray(xx, &x));
18: t = a->solve_work;
20: PetscCall(ISGetIndices(isrow, &rout));
21: r = rout;
22: PetscCall(ISGetIndices(iscol, &cout));
23: c = cout;
25: /* copy the b into temp work space according to permutation */
26: for (i = 0; i < n; i++) {
27: for (j = 0; j < bs; j++) t[i * bs + j] = b[c[i] * bs + j];
28: }
30: /* forward solve the upper triangular transpose */
31: ls = a->solve_work + A->cmap->n;
32: for (i = 0; i < n; i++) {
33: PetscCall(PetscArraycpy(ls, t + i * bs, bs));
34: PetscKernel_w_gets_transA_times_v(bs, ls, aa + bs2 * a->diag[i], t + i * bs);
35: v = aa + bs2 * (a->diag[i] + 1);
36: vi = aj + a->diag[i] + 1;
37: nz = ai[i + 1] - a->diag[i] - 1;
38: while (nz--) {
39: PetscKernel_v_gets_v_minus_transA_times_w(bs, t + bs * (*vi++), v, t + i * bs);
40: v += bs2;
41: }
42: }
44: /* backward solve the lower triangular transpose */
45: for (i = n - 1; i >= 0; i--) {
46: v = aa + bs2 * ai[i];
47: vi = aj + ai[i];
48: nz = a->diag[i] - ai[i];
49: while (nz--) {
50: PetscKernel_v_gets_v_minus_transA_times_w(bs, t + bs * (*vi++), v, t + i * bs);
51: v += bs2;
52: }
53: }
55: /* copy t into x according to permutation */
56: for (i = 0; i < n; i++) {
57: for (j = 0; j < bs; j++) x[bs * r[i] + j] = t[bs * i + j];
58: }
60: PetscCall(ISRestoreIndices(isrow, &rout));
61: PetscCall(ISRestoreIndices(iscol, &cout));
62: PetscCall(VecRestoreArrayRead(bb, &b));
63: PetscCall(VecRestoreArray(xx, &x));
64: PetscCall(PetscLogFlops(2.0 * (a->bs2) * (a->nz) - A->rmap->bs * A->cmap->n));
65: PetscFunctionReturn(PETSC_SUCCESS);
66: }
68: PetscErrorCode MatSolveTranspose_SeqBAIJ_N(Mat A, Vec bb, Vec xx)
69: {
70: Mat_SeqBAIJ *a = (Mat_SeqBAIJ *)A->data;
71: IS iscol = a->col, isrow = a->row;
72: const PetscInt *r, *c, *rout, *cout;
73: const PetscInt n = a->mbs, *ai = a->i, *aj = a->j, *vi, *diag = a->diag;
74: PetscInt i, j, nz;
75: const PetscInt bs = A->rmap->bs, bs2 = a->bs2;
76: const MatScalar *aa = a->a, *v;
77: PetscScalar *x, *t, *ls;
78: const PetscScalar *b;
80: PetscFunctionBegin;
81: PetscCall(VecGetArrayRead(bb, &b));
82: PetscCall(VecGetArray(xx, &x));
83: t = a->solve_work;
85: PetscCall(ISGetIndices(isrow, &rout));
86: r = rout;
87: PetscCall(ISGetIndices(iscol, &cout));
88: c = cout;
90: /* copy the b into temp work space according to permutation */
91: for (i = 0; i < n; i++) {
92: for (j = 0; j < bs; j++) t[i * bs + j] = b[c[i] * bs + j];
93: }
95: /* forward solve the upper triangular transpose */
96: ls = a->solve_work + A->cmap->n;
97: for (i = 0; i < n; i++) {
98: PetscCall(PetscArraycpy(ls, t + i * bs, bs));
99: PetscKernel_w_gets_transA_times_v(bs, ls, aa + bs2 * diag[i], t + i * bs);
100: v = aa + bs2 * (diag[i] - 1);
101: vi = aj + diag[i] - 1;
102: nz = diag[i] - diag[i + 1] - 1;
103: for (j = 0; j > -nz; j--) {
104: PetscKernel_v_gets_v_minus_transA_times_w(bs, t + bs * (vi[j]), v, t + i * bs);
105: v -= bs2;
106: }
107: }
109: /* backward solve the lower triangular transpose */
110: for (i = n - 1; i >= 0; i--) {
111: v = aa + bs2 * ai[i];
112: vi = aj + ai[i];
113: nz = ai[i + 1] - ai[i];
114: for (j = 0; j < nz; j++) {
115: PetscKernel_v_gets_v_minus_transA_times_w(bs, t + bs * (vi[j]), v, t + i * bs);
116: v += bs2;
117: }
118: }
120: /* copy t into x according to permutation */
121: for (i = 0; i < n; i++) {
122: for (j = 0; j < bs; j++) x[bs * r[i] + j] = t[bs * i + j];
123: }
125: PetscCall(ISRestoreIndices(isrow, &rout));
126: PetscCall(ISRestoreIndices(iscol, &cout));
127: PetscCall(VecRestoreArrayRead(bb, &b));
128: PetscCall(VecRestoreArray(xx, &x));
129: PetscCall(PetscLogFlops(2.0 * (a->bs2) * (a->nz) - A->rmap->bs * A->cmap->n));
130: PetscFunctionReturn(PETSC_SUCCESS);
131: }