1 2 /* 3 This is included by sbaij.c to generate unsigned short and regular versions of these two functions 4 */ 5 6 /* We cut-and-past below from aij.h to make a "no_function" version of PetscSparseDensePlusDot(). 7 * This is necessary because the USESHORT case cannot use the inlined functions that may be employed. */ 8 9 #if defined(PETSC_KERNEL_USE_UNROLL_4) 10 #define PetscSparseDensePlusDot_no_function(sum,r,xv,xi,nnz) { \ 11 if (nnz > 0) { \ 12 PetscInt nnz2=nnz,rem=nnz&0x3; \ 13 switch (rem) { \ 14 case 3: sum += *xv++ *r[*xi++]; \ 15 case 2: sum += *xv++ *r[*xi++]; \ 16 case 1: sum += *xv++ *r[*xi++]; \ 17 nnz2 -= rem;} \ 18 while (nnz2 > 0) { \ 19 sum += xv[0] * r[xi[0]] + xv[1] * r[xi[1]] + \ 20 xv[2] * r[xi[2]] + xv[3] * r[xi[3]]; \ 21 xv += 4; xi += 4; nnz2 -= 4; \ 22 } \ 23 xv -= nnz; xi -= nnz; \ 24 } \ 25 } 26 27 #elif defined(PETSC_KERNEL_USE_UNROLL_2) 28 #define PetscSparseDensePlusDot_no_function(sum,r,xv,xi,nnz) { \ 29 PetscInt __i,__i1,__i2; \ 30 for (__i=0; __i<nnz-1; __i+=2) {__i1 = xi[__i]; __i2=xi[__i+1]; \ 31 sum += (xv[__i]*r[__i1] + xv[__i+1]*r[__i2]);} \ 32 if (nnz & 0x1) sum += xv[__i] * r[xi[__i]];} 33 34 #else 35 #define PetscSparseDensePlusDot_no_function(sum,r,xv,xi,nnz) { \ 36 PetscInt __i; \ 37 for (__i=0; __i<nnz; __i++) sum += xv[__i] * r[xi[__i]];} 38 #endif 39 40 #if defined(USESHORT) 41 PetscErrorCode MatMult_SeqSBAIJ_1_ushort(Mat A,Vec xx,Vec zz) 42 #else 43 PetscErrorCode MatMult_SeqSBAIJ_1(Mat A,Vec xx,Vec zz) 44 #endif 45 { 46 Mat_SeqSBAIJ *a = (Mat_SeqSBAIJ*)A->data; 47 const PetscScalar *x; 48 PetscScalar *z,x1,sum; 49 const MatScalar *v; 50 MatScalar vj; 51 PetscErrorCode ierr; 52 PetscInt mbs=a->mbs,i,j,nz; 53 const PetscInt *ai=a->i; 54 #if defined(USESHORT) 55 const unsigned short *ib=a->jshort; 56 unsigned short ibt; 57 #else 58 const PetscInt *ib=a->j; 59 PetscInt ibt; 60 #endif 61 PetscInt nonzerorow=0,jmin; 62 #if defined(PETSC_USE_COMPLEX) 63 const int aconj = A->hermitian; 64 #else 65 const int aconj = 0; 66 #endif 67 68 PetscFunctionBegin; 69 ierr = VecSet(zz,0.0);CHKERRQ(ierr); 70 ierr = VecGetArrayRead(xx,&x);CHKERRQ(ierr); 71 ierr = VecGetArray(zz,&z);CHKERRQ(ierr); 72 73 v = a->a; 74 for (i=0; i<mbs; i++) { 75 nz = ai[i+1] - ai[i]; /* length of i_th row of A */ 76 if (!nz) continue; /* Move to the next row if the current row is empty */ 77 nonzerorow++; 78 sum = 0.0; 79 jmin = 0; 80 x1 = x[i]; 81 if (ib[0] == i) { 82 sum = v[0]*x1; /* diagonal term */ 83 jmin++; 84 } 85 PetscPrefetchBlock(ib+nz,nz,0,PETSC_PREFETCH_HINT_NTA); /* Indices for the next row (assumes same size as this one) */ 86 PetscPrefetchBlock(v+nz,nz,0,PETSC_PREFETCH_HINT_NTA); /* Entries for the next row */ 87 if (aconj) { 88 for (j=jmin; j<nz; j++) { 89 ibt = ib[j]; 90 vj = v[j]; 91 z[ibt] += PetscConj(vj) * x1; /* (strict lower triangular part of A)*x */ 92 sum += vj * x[ibt]; /* (strict upper triangular part of A)*x */ 93 } 94 } else { 95 for (j=jmin; j<nz; j++) { 96 ibt = ib[j]; 97 vj = v[j]; 98 z[ibt] += vj * x1; /* (strict lower triangular part of A)*x */ 99 sum += vj * x[ibt]; /* (strict upper triangular part of A)*x */ 100 } 101 } 102 z[i] += sum; 103 v += nz; 104 ib += nz; 105 } 106 107 ierr = VecRestoreArrayRead(xx,&x);CHKERRQ(ierr); 108 ierr = VecRestoreArray(zz,&z);CHKERRQ(ierr); 109 ierr = PetscLogFlops(2.0*(2.0*a->nz - nonzerorow) - nonzerorow);CHKERRQ(ierr); 110 PetscFunctionReturn(0); 111 } 112 113 #if defined(USESHORT) 114 PetscErrorCode MatSOR_SeqSBAIJ_ushort(Mat A,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx) 115 #else 116 PetscErrorCode MatSOR_SeqSBAIJ(Mat A,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx) 117 #endif 118 { 119 Mat_SeqSBAIJ *a = (Mat_SeqSBAIJ*)A->data; 120 const MatScalar *aa=a->a,*v,*v1,*aidiag; 121 PetscScalar *x,*t,sum; 122 const PetscScalar *b; 123 MatScalar tmp; 124 PetscErrorCode ierr; 125 PetscInt m =a->mbs,bs=A->rmap->bs,j; 126 const PetscInt *ai=a->i; 127 #if defined(USESHORT) 128 const unsigned short *aj=a->jshort,*vj,*vj1; 129 #else 130 const PetscInt *aj=a->j,*vj,*vj1; 131 #endif 132 PetscInt nz,nz1,i; 133 134 PetscFunctionBegin; 135 if (fshift == -1.0) fshift = 0.0; /* negative fshift indicates do not error on zero diagonal; this code never errors on zero diagonal */ 136 if (flag & SOR_EISENSTAT) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support yet for Eisenstat"); 137 138 its = its*lits; 139 if (its <= 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Relaxation requires global its %D and local its %D both positive",its,lits); 140 141 if (bs > 1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"SSOR for block size > 1 is not yet implemented"); 142 143 ierr = VecGetArray(xx,&x);CHKERRQ(ierr); 144 ierr = VecGetArrayRead(bb,&b);CHKERRQ(ierr); 145 146 if (!a->idiagvalid) { 147 if (!a->idiag) { 148 ierr = PetscMalloc1(m,&a->idiag);CHKERRQ(ierr); 149 } 150 for (i=0; i<a->mbs; i++) a->idiag[i] = 1.0/a->a[a->i[i]]; 151 a->idiagvalid = PETSC_TRUE; 152 } 153 154 if (!a->sor_work) { 155 ierr = PetscMalloc1(m,&a->sor_work);CHKERRQ(ierr); 156 } 157 t = a->sor_work; 158 159 aidiag = a->idiag; 160 161 if (flag == SOR_APPLY_UPPER) { 162 /* apply (U + D/omega) to the vector */ 163 PetscScalar d; 164 for (i=0; i<m; i++) { 165 d = fshift + aa[ai[i]]; 166 nz = ai[i+1] - ai[i] - 1; 167 vj = aj + ai[i] + 1; 168 v = aa + ai[i] + 1; 169 sum = b[i]*d/omega; 170 #ifdef USESHORT 171 PetscSparseDensePlusDot_no_function(sum,b,v,vj,nz); 172 #else 173 PetscSparseDensePlusDot(sum,b,v,vj,nz); 174 #endif 175 x[i] = sum; 176 } 177 ierr = PetscLogFlops(a->nz);CHKERRQ(ierr); 178 } 179 180 if (flag & SOR_ZERO_INITIAL_GUESS) { 181 if (flag & SOR_FORWARD_SWEEP || flag & SOR_LOCAL_FORWARD_SWEEP) { 182 ierr = PetscArraycpy(t,b,m);CHKERRQ(ierr); 183 184 v = aa + 1; 185 vj = aj + 1; 186 for (i=0; i<m; i++) { 187 nz = ai[i+1] - ai[i] - 1; 188 tmp = -(x[i] = omega*t[i]*aidiag[i]); 189 for (j=0; j<nz; j++) t[vj[j]] += tmp*v[j]; 190 v += nz + 1; 191 vj += nz + 1; 192 } 193 ierr = PetscLogFlops(2.0*a->nz);CHKERRQ(ierr); 194 } 195 196 if (flag & SOR_BACKWARD_SWEEP || flag & SOR_LOCAL_BACKWARD_SWEEP) { 197 int nz2; 198 if (!(flag & SOR_FORWARD_SWEEP || flag & SOR_LOCAL_FORWARD_SWEEP)) { 199 #if defined(PETSC_USE_BACKWARD_LOOP) 200 v = aa + ai[m] - 1; 201 vj = aj + ai[m] - 1; 202 for (i=m-1; i>=0; i--) { 203 sum = b[i]; 204 nz = ai[i+1] - ai[i] - 1; 205 {PetscInt __i;for (__i=0; __i<nz; __i++) sum -= v[-__i] * x[vj[-__i]];} 206 #else 207 v = aa + ai[m-1] + 1; 208 vj = aj + ai[m-1] + 1; 209 nz = 0; 210 for (i=m-1; i>=0; i--) { 211 sum = b[i]; 212 nz2 = ai[i] - ai[PetscMax(i-1,0)] - 1; /* avoid referencing ai[-1], nonsense nz2 is okay on last iteration */ 213 PETSC_Prefetch(v-nz2-1,0,PETSC_PREFETCH_HINT_NTA); 214 PETSC_Prefetch(vj-nz2-1,0,PETSC_PREFETCH_HINT_NTA); 215 PetscSparseDenseMinusDot(sum,x,v,vj,nz); 216 nz = nz2; 217 #endif 218 x[i] = omega*sum*aidiag[i]; 219 v -= nz + 1; 220 vj -= nz + 1; 221 } 222 ierr = PetscLogFlops(2.0*a->nz);CHKERRQ(ierr); 223 } else { 224 v = aa + ai[m-1] + 1; 225 vj = aj + ai[m-1] + 1; 226 nz = 0; 227 for (i=m-1; i>=0; i--) { 228 sum = t[i]; 229 nz2 = ai[i] - ai[PetscMax(i-1,0)] - 1; /* avoid referencing ai[-1], nonsense nz2 is okay on last iteration */ 230 PETSC_Prefetch(v-nz2-1,0,PETSC_PREFETCH_HINT_NTA); 231 PETSC_Prefetch(vj-nz2-1,0,PETSC_PREFETCH_HINT_NTA); 232 PetscSparseDenseMinusDot(sum,x,v,vj,nz); 233 x[i] = (1-omega)*x[i] + omega*sum*aidiag[i]; 234 nz = nz2; 235 v -= nz + 1; 236 vj -= nz + 1; 237 } 238 ierr = PetscLogFlops(2.0*a->nz);CHKERRQ(ierr); 239 } 240 } 241 its--; 242 } 243 244 while (its--) { 245 /* 246 forward sweep: 247 for i=0,...,m-1: 248 sum[i] = (b[i] - U(i,:)x)/d[i]; 249 x[i] = (1-omega)x[i] + omega*sum[i]; 250 b = b - x[i]*U^T(i,:); 251 252 */ 253 if (flag & SOR_FORWARD_SWEEP || flag & SOR_LOCAL_FORWARD_SWEEP) { 254 ierr = PetscArraycpy(t,b,m);CHKERRQ(ierr); 255 256 for (i=0; i<m; i++) { 257 v = aa + ai[i] + 1; v1=v; 258 vj = aj + ai[i] + 1; vj1=vj; 259 nz = ai[i+1] - ai[i] - 1; nz1=nz; 260 sum = t[i]; 261 while (nz1--) sum -= (*v1++)*x[*vj1++]; 262 x[i] = (1-omega)*x[i] + omega*sum*aidiag[i]; 263 while (nz--) t[*vj++] -= x[i]*(*v++); 264 } 265 ierr = PetscLogFlops(4.0*a->nz);CHKERRQ(ierr); 266 } 267 268 if (flag & SOR_BACKWARD_SWEEP || flag & SOR_LOCAL_BACKWARD_SWEEP) { 269 /* 270 backward sweep: 271 b = b - x[i]*U^T(i,:), i=0,...,n-2 272 for i=m-1,...,0: 273 sum[i] = (b[i] - U(i,:)x)/d[i]; 274 x[i] = (1-omega)x[i] + omega*sum[i]; 275 */ 276 /* if there was a forward sweep done above then I thing the next two for loops are not needed */ 277 ierr = PetscArraycpy(t,b,m);CHKERRQ(ierr); 278 279 for (i=0; i<m-1; i++) { /* update rhs */ 280 v = aa + ai[i] + 1; 281 vj = aj + ai[i] + 1; 282 nz = ai[i+1] - ai[i] - 1; 283 while (nz--) t[*vj++] -= x[i]*(*v++); 284 } 285 ierr = PetscLogFlops(2.0*(a->nz - m));CHKERRQ(ierr); 286 for (i=m-1; i>=0; i--) { 287 v = aa + ai[i] + 1; 288 vj = aj + ai[i] + 1; 289 nz = ai[i+1] - ai[i] - 1; 290 sum = t[i]; 291 while (nz--) sum -= x[*vj++]*(*v++); 292 x[i] = (1-omega)*x[i] + omega*sum*aidiag[i]; 293 } 294 ierr = PetscLogFlops(2.0*(a->nz + m));CHKERRQ(ierr); 295 } 296 } 297 298 ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr); 299 ierr = VecRestoreArrayRead(bb,&b);CHKERRQ(ierr); 300 PetscFunctionReturn(0); 301 } 302