Actual source code: baijsolvnat5.c
petsc-3.12.5 2020-03-29
1: #include <../src/mat/impls/baij/seq/baij.h>
2: #include <petsc/private/kernels/blockinvert.h>
4: PetscErrorCode MatSolve_SeqBAIJ_5_NaturalOrdering_inplace(Mat A,Vec bb,Vec xx)
5: {
6: Mat_SeqBAIJ *a = (Mat_SeqBAIJ*)A->data;
7: const PetscInt *diag=a->diag,n=a->mbs,*vi,*ai=a->i,*aj=a->j;
8: PetscInt i,nz,idx,idt,jdx;
9: PetscErrorCode ierr;
10: const MatScalar *aa=a->a,*v;
11: PetscScalar *x,s1,s2,s3,s4,s5,x1,x2,x3,x4,x5;
12: const PetscScalar *b;
15: VecGetArrayRead(bb,&b);
16: VecGetArray(xx,&x);
17: /* forward solve the lower triangular */
18: idx = 0;
19: x[0] = b[idx]; x[1] = b[1+idx]; x[2] = b[2+idx]; x[3] = b[3+idx];x[4] = b[4+idx];
20: for (i=1; i<n; i++) {
21: v = aa + 25*ai[i];
22: vi = aj + ai[i];
23: nz = diag[i] - ai[i];
24: idx = 5*i;
25: s1 = b[idx];s2 = b[1+idx];s3 = b[2+idx];s4 = b[3+idx];s5 = b[4+idx];
26: while (nz--) {
27: jdx = 5*(*vi++);
28: x1 = x[jdx];x2 = x[1+jdx];x3 = x[2+jdx];x4 = x[3+jdx];x5 = x[4+jdx];
29: s1 -= v[0]*x1 + v[5]*x2 + v[10]*x3 + v[15]*x4 + v[20]*x5;
30: s2 -= v[1]*x1 + v[6]*x2 + v[11]*x3 + v[16]*x4 + v[21]*x5;
31: s3 -= v[2]*x1 + v[7]*x2 + v[12]*x3 + v[17]*x4 + v[22]*x5;
32: s4 -= v[3]*x1 + v[8]*x2 + v[13]*x3 + v[18]*x4 + v[23]*x5;
33: s5 -= v[4]*x1 + v[9]*x2 + v[14]*x3 + v[19]*x4 + v[24]*x5;
34: v += 25;
35: }
36: x[idx] = s1;
37: x[1+idx] = s2;
38: x[2+idx] = s3;
39: x[3+idx] = s4;
40: x[4+idx] = s5;
41: }
42: /* backward solve the upper triangular */
43: for (i=n-1; i>=0; i--) {
44: v = aa + 25*diag[i] + 25;
45: vi = aj + diag[i] + 1;
46: nz = ai[i+1] - diag[i] - 1;
47: idt = 5*i;
48: s1 = x[idt]; s2 = x[1+idt];
49: s3 = x[2+idt];s4 = x[3+idt]; s5 = x[4+idt];
50: while (nz--) {
51: idx = 5*(*vi++);
52: x1 = x[idx]; x2 = x[1+idx];x3 = x[2+idx]; x4 = x[3+idx]; x5 = x[4+idx];
53: s1 -= v[0]*x1 + v[5]*x2 + v[10]*x3 + v[15]*x4 + v[20]*x5;
54: s2 -= v[1]*x1 + v[6]*x2 + v[11]*x3 + v[16]*x4 + v[21]*x5;
55: s3 -= v[2]*x1 + v[7]*x2 + v[12]*x3 + v[17]*x4 + v[22]*x5;
56: s4 -= v[3]*x1 + v[8]*x2 + v[13]*x3 + v[18]*x4 + v[23]*x5;
57: s5 -= v[4]*x1 + v[9]*x2 + v[14]*x3 + v[19]*x4 + v[24]*x5;
58: v += 25;
59: }
60: v = aa + 25*diag[i];
61: x[idt] = v[0]*s1 + v[5]*s2 + v[10]*s3 + v[15]*s4 + v[20]*s5;
62: x[1+idt] = v[1]*s1 + v[6]*s2 + v[11]*s3 + v[16]*s4 + v[21]*s5;
63: x[2+idt] = v[2]*s1 + v[7]*s2 + v[12]*s3 + v[17]*s4 + v[22]*s5;
64: x[3+idt] = v[3]*s1 + v[8]*s2 + v[13]*s3 + v[18]*s4 + v[23]*s5;
65: x[4+idt] = v[4]*s1 + v[9]*s2 + v[14]*s3 + v[19]*s4 + v[24]*s5;
66: }
68: VecRestoreArrayRead(bb,&b);
69: VecRestoreArray(xx,&x);
70: PetscLogFlops(2.0*25*(a->nz) - 5.0*A->cmap->n);
71: return(0);
72: }
74: PetscErrorCode MatSolve_SeqBAIJ_5_NaturalOrdering(Mat A,Vec bb,Vec xx)
75: {
76: Mat_SeqBAIJ *a = (Mat_SeqBAIJ*)A->data;
77: const PetscInt n = a->mbs,*vi,*ai=a->i,*aj=a->j,*adiag=a->diag;
78: PetscInt i,k,nz,idx,idt,jdx;
79: PetscErrorCode ierr;
80: const MatScalar *aa=a->a,*v;
81: PetscScalar *x,s1,s2,s3,s4,s5,x1,x2,x3,x4,x5;
82: const PetscScalar *b;
85: VecGetArrayRead(bb,&b);
86: VecGetArray(xx,&x);
87: /* forward solve the lower triangular */
88: idx = 0;
89: x[0] = b[idx]; x[1] = b[1+idx]; x[2] = b[2+idx]; x[3] = b[3+idx];x[4] = b[4+idx];
90: for (i=1; i<n; i++) {
91: v = aa + 25*ai[i];
92: vi = aj + ai[i];
93: nz = ai[i+1] - ai[i];
94: idx = 5*i;
95: s1 = b[idx];s2 = b[1+idx];s3 = b[2+idx];s4 = b[3+idx];s5 = b[4+idx];
96: for (k=0; k<nz; k++) {
97: jdx = 5*vi[k];
98: x1 = x[jdx];x2 = x[1+jdx];x3 = x[2+jdx];x4 = x[3+jdx];x5 = x[4+jdx];
99: s1 -= v[0]*x1 + v[5]*x2 + v[10]*x3 + v[15]*x4 + v[20]*x5;
100: s2 -= v[1]*x1 + v[6]*x2 + v[11]*x3 + v[16]*x4 + v[21]*x5;
101: s3 -= v[2]*x1 + v[7]*x2 + v[12]*x3 + v[17]*x4 + v[22]*x5;
102: s4 -= v[3]*x1 + v[8]*x2 + v[13]*x3 + v[18]*x4 + v[23]*x5;
103: s5 -= v[4]*x1 + v[9]*x2 + v[14]*x3 + v[19]*x4 + v[24]*x5;
104: v += 25;
105: }
106: x[idx] = s1;
107: x[1+idx] = s2;
108: x[2+idx] = s3;
109: x[3+idx] = s4;
110: x[4+idx] = s5;
111: }
113: /* backward solve the upper triangular */
114: for (i=n-1; i>=0; i--) {
115: v = aa + 25*(adiag[i+1]+1);
116: vi = aj + adiag[i+1]+1;
117: nz = adiag[i] - adiag[i+1]-1;
118: idt = 5*i;
119: s1 = x[idt]; s2 = x[1+idt];
120: s3 = x[2+idt];s4 = x[3+idt]; s5 = x[4+idt];
121: for (k=0; k<nz; k++) {
122: idx = 5*vi[k];
123: x1 = x[idx]; x2 = x[1+idx];x3 = x[2+idx]; x4 = x[3+idx]; x5 = x[4+idx];
124: s1 -= v[0]*x1 + v[5]*x2 + v[10]*x3 + v[15]*x4 + v[20]*x5;
125: s2 -= v[1]*x1 + v[6]*x2 + v[11]*x3 + v[16]*x4 + v[21]*x5;
126: s3 -= v[2]*x1 + v[7]*x2 + v[12]*x3 + v[17]*x4 + v[22]*x5;
127: s4 -= v[3]*x1 + v[8]*x2 + v[13]*x3 + v[18]*x4 + v[23]*x5;
128: s5 -= v[4]*x1 + v[9]*x2 + v[14]*x3 + v[19]*x4 + v[24]*x5;
129: v += 25;
130: }
131: /* x = inv_diagonal*x */
132: x[idt] = v[0]*s1 + v[5]*s2 + v[10]*s3 + v[15]*s4 + v[20]*s5;
133: x[1+idt] = v[1]*s1 + v[6]*s2 + v[11]*s3 + v[16]*s4 + v[21]*s5;
134: x[2+idt] = v[2]*s1 + v[7]*s2 + v[12]*s3 + v[17]*s4 + v[22]*s5;
135: x[3+idt] = v[3]*s1 + v[8]*s2 + v[13]*s3 + v[18]*s4 + v[23]*s5;
136: x[4+idt] = v[4]*s1 + v[9]*s2 + v[14]*s3 + v[19]*s4 + v[24]*s5;
137: }
139: VecRestoreArrayRead(bb,&b);
140: VecRestoreArray(xx,&x);
141: PetscLogFlops(2.0*25*(a->nz) - 5.0*A->cmap->n);
142: return(0);
143: }