Actual source code: baijsolvtran4.c

  1: #include <../src/mat/impls/baij/seq/baij.h>
  2: #include <petsc/private/kernels/blockinvert.h>

  4: PetscErrorCode MatSolveTranspose_SeqBAIJ_4_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;
  9:   const PetscInt    *diag=a->diag,n=a->mbs,*vi,*ai=a->i,*aj=a->j;
 10:   PetscInt          i,nz,idx,idt,ii,ic,ir,oidx;
 11:   const MatScalar   *aa=a->a,*v;
 12:   PetscScalar       s1,s2,s3,s4,x1,x2,x3,x4,*x,*t;
 13:   const PetscScalar *b;

 15:   VecGetArrayRead(bb,&b);
 16:   VecGetArray(xx,&x);
 17:   t    = a->solve_work;

 19:   ISGetIndices(isrow,&rout); r = rout;
 20:   ISGetIndices(iscol,&cout); c = cout;

 22:   /* copy the b into temp work space according to permutation */
 23:   ii = 0;
 24:   for (i=0; i<n; i++) {
 25:     ic      = 4*c[i];
 26:     t[ii]   = b[ic];
 27:     t[ii+1] = b[ic+1];
 28:     t[ii+2] = b[ic+2];
 29:     t[ii+3] = b[ic+3];
 30:     ii     += 4;
 31:   }

 33:   /* forward solve the U^T */
 34:   idx = 0;
 35:   for (i=0; i<n; i++) {

 37:     v = aa + 16*diag[i];
 38:     /* multiply by the inverse of the block diagonal */
 39:     x1 = t[idx];   x2 = t[1+idx]; x3    = t[2+idx]; x4 = t[3+idx];
 40:     s1 = v[0]*x1  +  v[1]*x2 +  v[2]*x3 +  v[3]*x4;
 41:     s2 = v[4]*x1  +  v[5]*x2 +  v[6]*x3 +  v[7]*x4;
 42:     s3 = v[8]*x1  +  v[9]*x2 + v[10]*x3 + v[11]*x4;
 43:     s4 = v[12]*x1 + v[13]*x2 + v[14]*x3 + v[15]*x4;
 44:     v += 16;

 46:     vi = aj + diag[i] + 1;
 47:     nz = ai[i+1] - diag[i] - 1;
 48:     while (nz--) {
 49:       oidx       = 4*(*vi++);
 50:       t[oidx]   -= v[0]*s1  +  v[1]*s2 +  v[2]*s3 +  v[3]*s4;
 51:       t[oidx+1] -= v[4]*s1  +  v[5]*s2 +  v[6]*s3 +  v[7]*s4;
 52:       t[oidx+2] -= v[8]*s1 + v[9]*s2 + v[10]*s3 + v[11]*s4;
 53:       t[oidx+3] -= v[12]*s1 + v[13]*s2 + v[14]*s3 + v[15]*s4;
 54:       v         += 16;
 55:     }
 56:     t[idx] = s1;t[1+idx] = s2; t[2+idx] = s3;t[3+idx] = s4;
 57:     idx   += 4;
 58:   }
 59:   /* backward solve the L^T */
 60:   for (i=n-1; i>=0; i--) {
 61:     v   = aa + 16*diag[i] - 16;
 62:     vi  = aj + diag[i] - 1;
 63:     nz  = diag[i] - ai[i];
 64:     idt = 4*i;
 65:     s1  = t[idt];  s2 = t[1+idt]; s3 = t[2+idt];s4 = t[3+idt];
 66:     while (nz--) {
 67:       idx       = 4*(*vi--);
 68:       t[idx]   -=  v[0]*s1 +  v[1]*s2 +  v[2]*s3 +  v[3]*s4;
 69:       t[idx+1] -=  v[4]*s1 +  v[5]*s2 +  v[6]*s3 +  v[7]*s4;
 70:       t[idx+2] -= v[8]*s1 + v[9]*s2 + v[10]*s3 + v[11]*s4;
 71:       t[idx+3] -= v[12]*s1 + v[13]*s2 + v[14]*s3 + v[15]*s4;
 72:       v        -= 16;
 73:     }
 74:   }

 76:   /* copy t into x according to permutation */
 77:   ii = 0;
 78:   for (i=0; i<n; i++) {
 79:     ir      = 4*r[i];
 80:     x[ir]   = t[ii];
 81:     x[ir+1] = t[ii+1];
 82:     x[ir+2] = t[ii+2];
 83:     x[ir+3] = t[ii+3];
 84:     ii     += 4;
 85:   }

 87:   ISRestoreIndices(isrow,&rout);
 88:   ISRestoreIndices(iscol,&cout);
 89:   VecRestoreArrayRead(bb,&b);
 90:   VecRestoreArray(xx,&x);
 91:   PetscLogFlops(2.0*16*(a->nz) - 4.0*A->cmap->n);
 92:   return 0;
 93: }

 95: PetscErrorCode MatSolveTranspose_SeqBAIJ_4(Mat A,Vec bb,Vec xx)
 96: {
 97:   Mat_SeqBAIJ       *a=(Mat_SeqBAIJ*)A->data;
 98:   IS                iscol=a->col,isrow=a->row;
 99:   const PetscInt    n    =a->mbs,*vi,*ai=a->i,*aj=a->j,*diag=a->diag;
100:   const PetscInt    *r,*c,*rout,*cout;
101:   PetscInt          nz,idx,idt,j,i,oidx,ii,ic,ir;
102:   const PetscInt    bs =A->rmap->bs,bs2=a->bs2;
103:   const MatScalar   *aa=a->a,*v;
104:   PetscScalar       s1,s2,s3,s4,x1,x2,x3,x4,*x,*t;
105:   const PetscScalar *b;

107:   VecGetArrayRead(bb,&b);
108:   VecGetArray(xx,&x);
109:   t    = a->solve_work;

111:   ISGetIndices(isrow,&rout); r = rout;
112:   ISGetIndices(iscol,&cout); c = cout;

114:   /* copy b into temp work space according to permutation */
115:   for (i=0; i<n; i++) {
116:     ii    = bs*i; ic = bs*c[i];
117:     t[ii] = b[ic]; t[ii+1] = b[ic+1]; t[ii+2] = b[ic+2]; t[ii+3] = b[ic+3];
118:   }

120:   /* forward solve the U^T */
121:   idx = 0;
122:   for (i=0; i<n; i++) {
123:     v = aa + bs2*diag[i];
124:     /* multiply by the inverse of the block diagonal */
125:     x1 = t[idx];   x2 = t[1+idx]; x3    = t[2+idx];  x4 = t[3+idx];
126:     s1 = v[0]*x1  +  v[1]*x2 +  v[2]*x3 +  v[3]*x4;
127:     s2 = v[4]*x1  +  v[5]*x2 +  v[6]*x3 +  v[7]*x4;
128:     s3 = v[8]*x1  +  v[9]*x2 + v[10]*x3 + v[11]*x4;
129:     s4 = v[12]*x1 + v[13]*x2 + v[14]*x3 + v[15]*x4;
130:     v -= bs2;

132:     vi = aj + diag[i] - 1;
133:     nz = diag[i] - diag[i+1] - 1;
134:     for (j=0; j>-nz; j--) {
135:       oidx       = bs*vi[j];
136:       t[oidx]   -= v[0]*s1  +  v[1]*s2 +  v[2]*s3 +  v[3]*s4;
137:       t[oidx+1] -= v[4]*s1  +  v[5]*s2 +  v[6]*s3 +  v[7]*s4;
138:       t[oidx+2] -= v[8]*s1 + v[9]*s2 + v[10]*s3 + v[11]*s4;
139:       t[oidx+3] -= v[12]*s1 + v[13]*s2 + v[14]*s3 + v[15]*s4;
140:       v         -= bs2;
141:     }
142:     t[idx] = s1;t[1+idx] = s2;  t[2+idx] = s3;  t[3+idx] = s4;
143:     idx   += bs;
144:   }
145:   /* backward solve the L^T */
146:   for (i=n-1; i>=0; i--) {
147:     v   = aa + bs2*ai[i];
148:     vi  = aj + ai[i];
149:     nz  = ai[i+1] - ai[i];
150:     idt = bs*i;
151:     s1  = t[idt];  s2 = t[1+idt];  s3 = t[2+idt];  s4 = t[3+idt];
152:     for (j=0; j<nz; j++) {
153:       idx       = bs*vi[j];
154:       t[idx]   -=  v[0]*s1 +  v[1]*s2 +  v[2]*s3  +  v[3]*s4;
155:       t[idx+1] -=  v[4]*s1 +  v[5]*s2 +  v[6]*s3  +  v[7]*s4;
156:       t[idx+2] -=  v[8]*s1 +  v[9]*s2 +  v[10]*s3 + v[11]*s4;
157:       t[idx+3] -= v[12]*s1 +  v[13]*s2 + v[14]*s3 + v[15]*s4;
158:       v        += bs2;
159:     }
160:   }

162:   /* copy t into x according to permutation */
163:   for (i=0; i<n; i++) {
164:     ii    = bs*i;  ir = bs*r[i];
165:     x[ir] = t[ii];  x[ir+1] = t[ii+1]; x[ir+2] = t[ii+2];  x[ir+3] = t[ii+3];
166:   }

168:   ISRestoreIndices(isrow,&rout);
169:   ISRestoreIndices(iscol,&cout);
170:   VecRestoreArrayRead(bb,&b);
171:   VecRestoreArray(xx,&x);
172:   PetscLogFlops(2.0*bs2*(a->nz) - bs*A->cmap->n);
173:   return 0;
174: }