magma_int_t
magma_sbicgstab_merge( magma_s_sparse_matrix A, magma_s_vector b,
magma_s_vector *x, magma_s_solver_par *solver_par ){
// prepare solver feedback
solver_par->solver = Magma_BICGSTABMERGE;
solver_par->numiter = 0;
solver_par->info = 0;
// some useful variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE;
magma_int_t dofs = A.num_rows;
// GPU stream
magma_queue_t stream[2];
magma_event_t event[1];
magma_queue_create( &stream[0] );
magma_queue_create( &stream[1] );
magma_event_create( &event[0] );
// workspace
magma_s_vector q, r,rr,p,v,s,t;
float *d1, *d2, *skp;
magma_smalloc( &d1, dofs*(2) );
magma_smalloc( &d2, dofs*(2) );
// array for the parameters
magma_smalloc( &skp, 8 );
// skp = [alpha|beta|omega|rho_old|rho|nom|tmp1|tmp2]
magma_s_vinit( &q, Magma_DEV, dofs*6, c_zero );
// q = rr|r|p|v|s|t
rr.memory_location = Magma_DEV; rr.val = NULL; rr.num_rows = rr.nnz = dofs;
r.memory_location = Magma_DEV; r.val = NULL; r.num_rows = r.nnz = dofs;
p.memory_location = Magma_DEV; p.val = NULL; p.num_rows = p.nnz = dofs;
v.memory_location = Magma_DEV; v.val = NULL; v.num_rows = v.nnz = dofs;
s.memory_location = Magma_DEV; s.val = NULL; s.num_rows = s.nnz = dofs;
t.memory_location = Magma_DEV; t.val = NULL; t.num_rows = t.nnz = dofs;
rr.val = q(0);
r.val = q(1);
p.val = q(2);
v.val = q(3);
s.val = q(4);
t.val = q(5);
// solver variables
float alpha, beta, omega, rho_old, rho_new, *skp_h;
float nom, nom0, betanom, r0, den;
// solver setup
magma_sscal( dofs, c_zero, x->val, 1) ; // x = 0
magma_scopy( dofs, b.val, 1, q(0), 1 ); // rr = b
magma_scopy( dofs, b.val, 1, q(1), 1 ); // r = b
rho_new = magma_sdot( dofs, r.val, 1, r.val, 1 ); // rho=<rr,r>
nom = MAGMA_S_REAL(magma_sdot( dofs, r.val, 1, r.val, 1 ));
nom0 = betanom = sqrt(nom); // nom = || r ||
rho_old = omega = alpha = MAGMA_S_MAKE( 1.0, 0. );
beta = rho_new;
solver_par->init_res = nom0;
// array on host for the parameters
magma_smalloc_cpu( &skp_h, 8 );
skp_h[0]=alpha;
skp_h[1]=beta;
skp_h[2]=omega;
skp_h[3]=rho_old;
skp_h[4]=rho_new;
skp_h[5]=MAGMA_S_MAKE(nom, 0.0);
magma_ssetvector( 8, skp_h, 1, skp, 1 );
magma_s_spmv( c_one, A, r, c_zero, v ); // z = A r
den = MAGMA_S_REAL( magma_sdot(dofs, v.val, 1, r.val, 1) );// den = z dot r
if ( (r0 = nom * solver_par->epsilon) < ATOLERANCE )
r0 = ATOLERANCE;
if ( nom < r0 )
return MAGMA_SUCCESS;
// check positive definite
if (den <= 0.0) {
printf("Operator A is not postive definite. (Ar,r) = %f\n", den);
return -100;
}
//Chronometry
real_Double_t tempo1, tempo2;
magma_device_sync(); tempo1=magma_wtime();
if( solver_par->verbose > 0 ){
solver_par->res_vec[0] = nom0;
solver_par->timing[0] = 0.0;
}
// start iteration
for( solver_par->numiter= 1; solver_par->numiter<solver_par->maxiter;
solver_par->numiter++ ){
magmablasSetKernelStream(stream[0]);
// computes p=r+beta*(p-omega*v)
magma_sbicgmerge1( dofs, skp, v.val, r.val, p.val );
magma_s_spmv( c_one, A, p, c_zero, v ); // v = Ap
magma_smdotc( dofs, 1, q.val, v.val, d1, d2, skp );
magma_sbicgmerge4( 1, skp );
magma_sbicgmerge2( dofs, skp, r.val, v.val, s.val ); // s=r-alpha*v
magma_s_spmv( c_one, A, s, c_zero, t ); // t=As
magma_smdotc( dofs, 2, q.val+4*dofs, t.val, d1, d2, skp+6 );
magma_sbicgmerge4( 2, skp );
magma_sbicgmerge3( dofs, skp, p.val, s.val, // x=x+alpha*p+omega*s
t.val, x->val, r.val ); // r=s-omega*t
magma_smdotc( dofs, 2, q.val, r.val, d1, d2, skp+4);
magma_sbicgmerge4( 3, skp );
// check stopping criterion (asynchronous copy)
magma_sgetvector_async( 1 , skp+5, 1,
skp_h+5, 1, stream[1] );
betanom = sqrt(MAGMA_S_REAL(skp_h[5]));
if( solver_par->verbose > 0 ){
magma_device_sync(); tempo2=magma_wtime();
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( betanom < r0 ) {
break;
}
}
magma_device_sync(); tempo2=magma_wtime();
solver_par->runtime = (real_Double_t) tempo2-tempo1;
float residual;
magma_sresidual( A, b, *x, &residual );
solver_par->iter_res = betanom;
solver_par->final_res = residual;
if( solver_par->numiter < solver_par->maxiter){
solver_par->info = 0;
}else if( solver_par->init_res > solver_par->final_res ){
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -2;
}
else{
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -1;
}
magma_s_vfree(&q); // frees all vectors
magma_free(d1);
magma_free(d2);
magma_free( skp );
magma_free_cpu( skp_h );
return MAGMA_SUCCESS;
} /* sbicgstab_merge */
extern "C" magma_int_t
magma_sbicgstab_merge3(
magma_s_matrix A, magma_s_matrix b,
magma_s_matrix *x, magma_s_solver_par *solver_par,
magma_queue_t queue )
{
magma_int_t info = MAGMA_NOTCONVERGED;
// prepare solver feedback
solver_par->solver = Magma_BICGSTABMERGE;
solver_par->numiter = 0;
solver_par->spmv_count = 0;
// solver variables
float alpha, beta, omega, rho_old, rho_new, *skp_h={0};
float nom, nom0, betanom, nomb;
// some useful variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE;
magma_int_t dofs = A.num_rows;
// workspace
magma_s_matrix q={Magma_CSR}, r={Magma_CSR}, rr={Magma_CSR}, p={Magma_CSR}, v={Magma_CSR}, s={Magma_CSR}, t={Magma_CSR};
float *d1=NULL, *d2=NULL, *skp=NULL;
d1 = NULL;
d2 = NULL;
skp = NULL;
CHECK( magma_smalloc( &d1, dofs*(2) ));
CHECK( magma_smalloc( &d2, dofs*(2) ));
// array for the parameters
CHECK( magma_smalloc( &skp, 8 ));
// skp = [alpha|beta|omega|rho_old|rho|nom|tmp1|tmp2]
CHECK( magma_svinit( &q, Magma_DEV, dofs*6, 1, c_zero, queue ));
// q = rr|r|p|v|s|t
rr.memory_location = Magma_DEV; rr.dval = NULL; rr.num_rows = rr.nnz = dofs; rr.num_cols = 1; rr.storage_type = Magma_DENSE;
r.memory_location = Magma_DEV; r.dval = NULL; r.num_rows = r.nnz = dofs; r.num_cols = 1; r.storage_type = Magma_DENSE;
p.memory_location = Magma_DEV; p.dval = NULL; p.num_rows = p.nnz = dofs; p.num_cols = 1; p.storage_type = Magma_DENSE;
v.memory_location = Magma_DEV; v.dval = NULL; v.num_rows = v.nnz = dofs; v.num_cols = 1; v.storage_type = Magma_DENSE;
s.memory_location = Magma_DEV; s.dval = NULL; s.num_rows = s.nnz = dofs; s.num_cols = 1; s.storage_type = Magma_DENSE;
t.memory_location = Magma_DEV; t.dval = NULL; t.num_rows = t.nnz = dofs; t.num_cols = 1; t.storage_type = Magma_DENSE;
rr.dval = q(0);
r.dval = q(1);
p.dval = q(2);
v.dval = q(3);
s.dval = q(4);
t.dval = q(5);
// solver setup
CHECK( magma_sresidualvec( A, b, *x, &r, &nom0, queue));
magma_scopy( dofs, r.dval, 1, q(0), 1, queue ); // rr = r
magma_scopy( dofs, r.dval, 1, q(1), 1, queue ); // q = r
betanom = nom0;
nom = nom0*nom0;
rho_new = magma_sdot( dofs, r.dval, 1, r.dval, 1, queue ); // rho=<rr,r>
rho_old = omega = alpha = MAGMA_S_MAKE( 1.0, 0. );
beta = rho_new;
solver_par->init_res = nom0;
// array on host for the parameters
CHECK( magma_smalloc_cpu( &skp_h, 8 ));
nomb = magma_snrm2( dofs, b.dval, 1, queue );
if ( nomb == 0.0 ){
nomb=1.0;
}
solver_par->final_res = solver_par->init_res;
solver_par->iter_res = solver_par->init_res;
if ( solver_par->verbose > 0 ) {
solver_par->res_vec[0] = nom0;
solver_par->timing[0] = 0.0;
}
skp_h[0]=alpha;
skp_h[1]=beta;
skp_h[2]=omega;
skp_h[3]=rho_old;
skp_h[4]=rho_new;
skp_h[5]=MAGMA_S_MAKE(nom, 0.0);
magma_ssetvector( 8, skp_h, 1, skp, 1, queue );
CHECK( magma_s_spmv( c_one, A, r, c_zero, v, queue )); // z = A r
nomb = magma_snrm2( dofs, b.dval, 1, queue );
if( nom0 < solver_par->atol ||
nom0/nomb < solver_par->rtol ){
info = MAGMA_SUCCESS;
goto cleanup;
}
//Chronometry
real_Double_t tempo1, tempo2;
tempo1 = magma_sync_wtime( queue );
solver_par->numiter = 0;
solver_par->spmv_count = 0;
// start iteration
do
{
solver_par->numiter++;
// computes p=r+beta*(p-omega*v)
CHECK( magma_sbicgmerge1( dofs, skp, v.dval, r.dval, p.dval, queue ));
CHECK( magma_s_spmv( c_one, A, p, c_zero, v, queue )); // v = Ap
solver_par->spmv_count++;
CHECK( magma_smdotc( dofs, 1, q.dval, v.dval, d1, d2, skp, queue ));
CHECK( magma_sbicgmerge4( 1, skp, queue ));
CHECK( magma_sbicgmerge2( dofs, skp, r.dval, v.dval, s.dval, queue )); // s=r-alpha*v
CHECK( magma_s_spmv( c_one, A, s, c_zero, t, queue )); // t=As
solver_par->spmv_count++;
CHECK( magma_smdotc( dofs, 2, q.dval+4*dofs, t.dval, d1, d2, skp+6, queue ));
CHECK( magma_sbicgmerge4( 2, skp, queue ));
CHECK( magma_sbicgmerge_xrbeta( dofs, d1, d2, q.dval, r.dval, p.dval,
s.dval, t.dval, x->dval, skp, queue ));
// check stopping criterion
magma_sgetvector_async( 1 , skp+5, 1, skp_h+5, 1, queue );
betanom = sqrt(MAGMA_S_REAL(skp_h[5]));
if ( solver_par->verbose > 0 ) {
tempo2 = magma_sync_wtime( queue );
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( betanom < solver_par->atol ||
betanom/nomb < solver_par->rtol ) {
break;
}
}
while ( solver_par->numiter+1 <= solver_par->maxiter );
tempo2 = magma_sync_wtime( queue );
solver_par->runtime = (real_Double_t) tempo2-tempo1;
float residual;
CHECK( magma_sresidualvec( A, b, *x, &r, &residual, queue));
solver_par->iter_res = betanom;
solver_par->final_res = residual;
if ( solver_par->numiter < solver_par->maxiter ) {
info = MAGMA_SUCCESS;
} else if ( solver_par->init_res > solver_par->final_res ) {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
info = MAGMA_SLOW_CONVERGENCE;
if( solver_par->iter_res < solver_par->atol ||
solver_par->iter_res/solver_par->init_res < solver_par->rtol ){
info = MAGMA_SUCCESS;
}
}
else {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
info = MAGMA_DIVERGENCE;
}
cleanup:
magma_smfree(&q, queue ); // frees all vectors
magma_free(d1);
magma_free(d2);
magma_free( skp );
magma_free_cpu( skp_h );
solver_par->info = info;
return info;
} /* sbicgstab_merge */
