/**
@deprecated
Purpose
-------
CLAQPS computes a step of QR factorization with column pivoting
of a complex M-by-N matrix A by using Blas-3. It tries to factorize
NB columns from A starting from the row OFFSET+1, and updates all
of the matrix with Blas-3 xGEMM.
In some cases, due to catastrophic cancellations, it cannot
factorize NB columns. Hence, the actual number of factorized
columns is returned in KB.
Block A(1:OFFSET,1:N) is accordingly pivoted, but not factorized.
Arguments
---------
@param[in]
m INTEGER
The number of rows of the matrix A. M >= 0.
@param[in]
n INTEGER
The number of columns of the matrix A. N >= 0
@param[in]
offset INTEGER
The number of rows of A that have been factorized in
previous steps.
@param[in]
nb INTEGER
The number of columns to factorize.
@param[out]
kb INTEGER
The number of columns actually factorized.
@param[in,out]
dA COMPLEX array, dimension (LDDA,N), on the GPU.
On entry, the M-by-N matrix A.
On exit, block A(OFFSET+1:M,1:KB) is the triangular
factor obtained and block A(1:OFFSET,1:N) has been
accordingly pivoted, but no factorized.
The rest of the matrix, block A(OFFSET+1:M,KB+1:N) has
been updated.
@param[in]
ldda INTEGER
The leading dimension of the array A. LDDA >= max(1,M).
@param[in,out]
jpvt INTEGER array, dimension (N)
JPVT(I) = K <==> Column K of the full matrix A has been
permuted into position I in AP.
@param[out]
tau COMPLEX array, dimension (KB)
The scalar factors of the elementary reflectors.
@param[in,out]
vn1 REAL array, dimension (N)
The vector with the partial column norms.
@param[in,out]
vn2 REAL array, dimension (N)
The vector with the exact column norms.
@param[in,out]
dauxv COMPLEX array, dimension (NB), on the GPU
Auxiliary vector.
@param[in,out]
dF COMPLEX array, dimension (LDDF,NB), on the GPU
Matrix F' = L*Y'*A.
@param[in]
lddf INTEGER
The leading dimension of the array F. LDDF >= max(1,N).
@ingroup magma_cgeqp3_aux
********************************************************************/
extern "C" magma_int_t
magma_claqps_gpu(
magma_int_t m, magma_int_t n, magma_int_t offset,
magma_int_t nb, magma_int_t *kb,
magmaFloatComplex_ptr dA, magma_int_t ldda,
magma_int_t *jpvt, magmaFloatComplex *tau,
float *vn1, float *vn2,
magmaFloatComplex_ptr dauxv,
magmaFloatComplex_ptr dF, magma_int_t lddf)
{
#define dA(i, j) (dA + (i) + (j)*(ldda))
#define dF(i, j) (dF + (i) + (j)*(lddf))
magmaFloatComplex c_zero = MAGMA_C_MAKE( 0.,0.);
magmaFloatComplex c_one = MAGMA_C_MAKE( 1.,0.);
magmaFloatComplex c_neg_one = MAGMA_C_MAKE(-1.,0.);
magma_int_t ione = 1;
magma_int_t i__1, i__2;
magmaFloatComplex z__1;
magma_int_t k, rk;
magmaFloatComplex_ptr dAks;
magmaFloatComplex tauk = MAGMA_C_ZERO;
magma_int_t pvt;
float tol3z;
magma_int_t itemp;
float lsticc;
magmaFloat_ptr dlsticcs;
magma_smalloc( &dlsticcs, 1+256*(n+255)/256 );
tol3z = magma_ssqrt( lapackf77_slamch("Epsilon"));
lsticc = 0;
k = 0;
magma_cmalloc( &dAks, nb );
magma_queue_t queue;
magma_device_t cdev;
magma_getdevice( &cdev );
magma_queue_create( cdev, &queue );
while( k < nb && lsticc == 0 ) {
rk = offset + k;
/* Determine ith pivot column and swap if necessary */
// subtract 1 from Fortran/CUBLAS isamax; pvt, k are 0-based.
pvt = k + magma_isamax( n-k, &vn1[k], ione, queue ) - 1;
if (pvt != k) {
/* F gets swapped so F must be sent at the end to GPU */
i__1 = k;
magmablas_cswap( m, dA(0, pvt), ione, dA(0, k), ione, queue );
magmablas_cswap( i__1, dF(pvt, 0), lddf, dF(k, 0), lddf, queue );
itemp = jpvt[pvt];
jpvt[pvt] = jpvt[k];
jpvt[k] = itemp;
magma_sswap( 2, &vn1[pvt], n+offset, &vn1[k], n+offset, queue );
}
/* Apply previous Householder reflectors to column K:
A(RK:M,K) := A(RK:M,K) - A(RK:M,1:K-1)*F(K,1:K-1)'.
Optimization: multiply with beta=0; wait for vector and subtract */
if (k > 0) {
//#define RIGHT_UPDATE
#ifdef RIGHT_UPDATE
i__1 = m - offset - nb;
i__2 = k;
magma_cgemv( MagmaNoTrans, i__1, i__2,
c_neg_one, A(offset+nb, 0), lda,
F(k, 0), ldf,
c_one, A(offset+nb, k), ione, queue );
#else
i__1 = m - rk;
i__2 = k;
magma_cgemv( MagmaNoTrans, i__1, i__2,
c_neg_one, dA(rk, 0), ldda,
dF(k, 0), lddf,
c_one, dA(rk, k), ione, queue );
#endif
}
/* Generate elementary reflector H(k). */
magma_clarfg_gpu( m-rk, dA(rk, k), dA(rk + 1, k), &tau[k], &vn1[k], &dAks[k], queue );
/* needed to avoid the race condition */
if (k == 0) magma_csetvector( 1, &c_one, 1, dA(rk, k), 1, queue );
else magma_ccopymatrix( 1, 1, dA(offset, 0), 1, dA(rk, k), 1, queue );
/* Compute Kth column of F:
Compute F(K+1:N,K) := tau(K)*A(RK:M,K+1:N)'*A(RK:M,K) on the GPU */
if (k < n-1 || k > 0) magma_cgetvector( 1, &tau[k], 1, &tauk, 1, queue );
if (k < n-1) {
i__1 = m - rk;
i__2 = n - k - 1;
/* Multiply on GPU */
magma_cgemv( MagmaConjTrans, m-rk, n-k-1,
tauk, dA( rk, k+1 ), ldda,
dA( rk, k ), 1,
c_zero, dF( k+1, k ), 1, queue );
}
/* Incremental updating of F:
F(1:N,K) := F(1:N,K) - tau(K)*F(1:N,1:K-1)*A(RK:M,1:K-1)'*A(RK:M,K).
F(1:N,K) := tau(K)*A(RK:M,K+1:N)'*A(RK:M,K) - tau(K)*F(1:N,1:K-1)*A(RK:M,1:K-1)'*A(RK:M,K)
:= tau(K)(A(RK:M,K+1:N)' - F(1:N,1:K-1)*A(RK:M,1:K-1)') A(RK:M,K)
so, F is (updated A)*V */
if (k > 0) {
z__1 = MAGMA_C_NEGATE( tauk );
#ifdef RIGHT_UPDATE
i__1 = m - offset - nb;
i__2 = k;
magma_cgemv( MagmaConjTrans, i__1, i__2,
z__1, dA(offset+nb, 0), lda,
dA(offset+nb, k), ione,
c_zero, dauxv, ione, queue );
i__1 = k;
magma_cgemv( MagmaNoTrans, n-k-1, i__1,
c_one, F(k+1,0), ldf,
dauxv, ione,
c_one, F(k+1,k), ione, queue );
#else
i__1 = m - rk;
i__2 = k;
magma_cgemv( MagmaConjTrans, i__1, i__2,
z__1, dA(rk, 0), ldda,
dA(rk, k), ione,
c_zero, dauxv, ione, queue );
/* I think we only need stricly lower-triangular part :) */
magma_cgemv( MagmaNoTrans, n-k-1, i__2,
c_one, dF(k+1,0), lddf,
dauxv, ione,
c_one, dF(k+1,k), ione, queue );
#endif
}
/* Optimization: On the last iteration start sending F back to the GPU */
/* Update the current row of A:
A(RK,K+1:N) := A(RK,K+1:N) - A(RK,1:K)*F(K+1:N,1:K)'. */
if (k < n-1) {
i__1 = n - k - 1;
i__2 = k + 1;
#ifdef RIGHT_UPDATE
/* right-looking update of rows, */
magma_cgemm( MagmaNoTrans, MagmaConjTrans, nb-k, i__1, ione,
c_neg_one, dA(rk, k ), ldda,
dF(k+1, k ), lddf,
c_one, dA(rk, k+1), ldda, queue );
#else
/* left-looking update of rows, *
* since F=A'v with original A, so no right-looking */
magma_cgemm( MagmaNoTrans, MagmaConjTrans, ione, i__1, i__2,
c_neg_one, dA(rk, 0 ), ldda,
dF(k+1,0 ), lddf,
c_one, dA(rk, k+1), ldda, queue );
#endif
}
/* Update partial column norms. */
if (rk < min(m, n+offset)-1 ) {
magmablas_scnrm2_row_check_adjust( n-k-1, tol3z, &vn1[k+1], &vn2[k+1],
dA(rk,k+1), ldda, dlsticcs, queue );
//magma_device_sync();
magma_sgetvector( 1, &dlsticcs[0], 1, &lsticc, 1, queue );
}
++k;
}
magma_ccopymatrix( 1, k, dAks, 1, dA(offset, 0), ldda+1, queue );
// leave k as the last column done
--k;
*kb = k + 1;
rk = offset + *kb - 1;
/* Apply the block reflector to the rest of the matrix:
A(OFFSET+KB+1:M,KB+1:N) := A(OFFSET+KB+1:M,KB+1:N) - A(OFFSET+KB+1:M,1:KB)*F(KB+1:N,1:KB)' */
if (*kb < min(n, m - offset)) {
i__1 = m - rk - 1;
i__2 = n - *kb;
magma_cgemm( MagmaNoTrans, MagmaConjTrans, i__1, i__2, *kb,
c_neg_one, dA(rk+1, 0 ), ldda,
dF(*kb, 0 ), lddf,
c_one, dA(rk+1, *kb), ldda, queue );
}
/* Recomputation of difficult columns. */
if ( lsticc > 0 ) {
// printf( " -- recompute dnorms --\n" );
magmablas_scnrm2_check( m-rk-1, n-*kb, dA(rk+1,*kb), ldda,
&vn1[*kb], dlsticcs, queue );
magma_scopymatrix( n-*kb, 1, &vn1[*kb], *kb, &vn2[*kb], *kb, queue );
}
magma_free( dAks );
magma_free( dlsticcs );
magma_queue_destroy( queue );
return MAGMA_SUCCESS;
} /* magma_claqps */
/**
@deprecated
Purpose
-------
CLAQPS computes a step of QR factorization with column pivoting
of a complex M-by-N matrix A by using Blas-3. It tries to factorize
NB columns from A starting from the row OFFSET+1, and updates all
of the matrix with Blas-3 xGEMM.
In some cases, due to catastrophic cancellations, it cannot
factorize NB columns. Hence, the actual number of factorized
columns is returned in KB.
Block A(1:OFFSET,1:N) is accordingly pivoted, but not factorized.
Arguments
---------
@param[in]
m INTEGER
The number of rows of the matrix A. M >= 0.
@param[in]
n INTEGER
The number of columns of the matrix A. N >= 0
@param[in]
offset INTEGER
The number of rows of A that have been factorized in
previous steps.
@param[in]
nb INTEGER
The number of columns to factorize.
@param[out]
kb INTEGER
The number of columns actually factorized.
@param[in,out]
A COMPLEX array, dimension (LDA,N)
On entry, the M-by-N matrix A.
On exit, block A(OFFSET+1:M,1:KB) is the triangular
factor obtained and block A(1:OFFSET,1:N) has been
accordingly pivoted, but no factorized.
The rest of the matrix, block A(OFFSET+1:M,KB+1:N) has
been updated.
@param[in]
lda INTEGER
The leading dimension of the array A. LDA >= max(1,M).
@param[in,out]
jpvt INTEGER array, dimension (N)
JPVT(I) = K <==> Column K of the full matrix A has been
permuted into position I in AP.
@param[out]
tau COMPLEX array, dimension (KB)
The scalar factors of the elementary reflectors.
@param[in,out]
vn1 REAL array, dimension (N)
The vector with the partial column norms.
@param[in,out]
vn2 REAL array, dimension (N)
The vector with the exact column norms.
@param[in,out]
auxv COMPLEX array, dimension (NB)
Auxiliar vector.
@param[in,out]
F COMPLEX array, dimension (LDF,NB)
Matrix F' = L*Y'*A.
@param[in]
ldf INTEGER
The leading dimension of the array F. LDF >= max(1,N).
@ingroup magma_cgeqp3_aux
********************************************************************/
extern "C" magma_int_t
magma_claqps_gpu(magma_int_t m, magma_int_t n, magma_int_t offset,
magma_int_t nb, magma_int_t *kb,
magmaFloatComplex *A, magma_int_t lda,
magma_int_t *jpvt, magmaFloatComplex *tau,
float *vn1, float *vn2,
magmaFloatComplex *auxv,
magmaFloatComplex *F, magma_int_t ldf)
{
#define A(i, j) (A + (i) + (j)*(lda ))
#define F(i, j) (F + (i) + (j)*(ldf ))
magmaFloatComplex c_zero = MAGMA_C_MAKE( 0.,0.);
magmaFloatComplex c_one = MAGMA_C_MAKE( 1.,0.);
magmaFloatComplex c_neg_one = MAGMA_C_MAKE(-1.,0.);
magma_int_t ione = 1;
magma_int_t i__1, i__2;
//float d__1;
magmaFloatComplex z__1;
//magma_int_t j;
magma_int_t k, rk;
//magmaFloatComplex Akk;
magmaFloatComplex *Aks;
magmaFloatComplex tauk = MAGMA_C_ZERO;
magma_int_t pvt;
//float temp, temp2;
float tol3z;
magma_int_t itemp;
float lsticc, *lsticcs;
magma_int_t lastrk;
magma_smalloc( &lsticcs, 1+256*(n+255)/256 );
lastrk = min( m, n + offset );
tol3z = magma_ssqrt( lapackf77_slamch("Epsilon"));
lsticc = 0;
k = 0;
magma_cmalloc( &Aks, nb );
while( k < nb && lsticc == 0 ) {
rk = offset + k;
/* Determine ith pivot column and swap if necessary */
// subtract 1 from Fortran/CUBLAS isamax; pvt, k are 0-based.
pvt = k + magma_isamax( n-k, &vn1[k], ione ) - 1;
if (pvt != k) {
/*if (pvt >= nb) {
// 1. Start copy from GPU
magma_cgetmatrix_async( m - offset - nb, 1,
dA(offset + nb, pvt), ldda,
A (offset + nb, pvt), lda, stream );
}*/
/* F gets swapped so F must be sent at the end to GPU */
i__1 = k;
/*if (pvt < nb) {
// no need of transfer if pivot is within the panel
blasf77_cswap( &m, A(0, pvt), &ione, A(0, k), &ione );
}
else {
// 1. Finish copy from GPU
magma_queue_sync( stream );
// 2. Swap as usual on CPU
blasf77_cswap(&m, A(0, pvt), &ione, A(0, k), &ione);
// 3. Restore the GPU
magma_csetmatrix_async( m - offset - nb, 1,
A (offset + nb, pvt), lda,
dA(offset + nb, pvt), ldda, stream);
}*/
magmablas_cswap( m, A(0, pvt), ione, A(0, k), ione );
//blasf77_cswap( &i__1, F(pvt,0), &ldf, F(k,0), &ldf );
magmablas_cswap( i__1, F(pvt, 0), ldf, F(k, 0), ldf);
itemp = jpvt[pvt];
jpvt[pvt] = jpvt[k];
jpvt[k] = itemp;
//vn1[pvt] = vn1[k];
//vn2[pvt] = vn2[k];
#if defined(PRECISION_d) || defined(PRECISION_z)
//magma_dswap( 1, &vn1[pvt], 1, &vn1[k], 1 );
//magma_dswap( 1, &vn2[pvt], 1, &vn2[k], 1 );
magma_dswap( 2, &vn1[pvt], n+offset, &vn1[k], n+offset );
#else
//magma_sswap( 1, &vn1[pvt], 1, &vn1[k], 1 );
//magma_sswap( 1, &vn2[pvt], 1, &vn2[k], 1 );
magma_sswap(2, &vn1[pvt], n+offset, &vn1[k], n+offset);
#endif
}
/* Apply previous Householder reflectors to column K:
A(RK:M,K) := A(RK:M,K) - A(RK:M,1:K-1)*F(K,1:K-1)'.
Optimization: multiply with beta=0; wait for vector and subtract */
if (k > 0) {
/*#if (defined(PRECISION_c) || defined(PRECISION_z))
for (j = 0; j < k; ++j) {
*F(k,j) = MAGMA_C_CNJG( *F(k,j) );
}
#endif*/
//#define RIGHT_UPDATE
#ifdef RIGHT_UPDATE
i__1 = m - offset - nb;
i__2 = k;
magma_cgemv( MagmaNoTrans, i__1, i__2,
c_neg_one, A(offset+nb, 0), lda,
F(k, 0), ldf,
c_one, A(offset+nb, k), ione );
#else
i__1 = m - rk;
i__2 = k;
/*blasf77_cgemv( MagmaNoTransStr, &i__1, &i__2,
&c_neg_one, A(rk, 0), &lda,
F(k, 0), &ldf,
&c_one, A(rk, k), &ione );*/
magma_cgemv( MagmaNoTrans, i__1, i__2,
c_neg_one, A(rk, 0), lda,
F(k, 0), ldf,
c_one, A(rk, k), ione );
#endif
/*#if (defined(PRECISION_c) || defined(PRECISION_z))
for (j = 0; j < k; ++j) {
*F(k,j) = MAGMA_C_CNJG( *F(k,j) );
}
#endif*/
}
/* Generate elementary reflector H(k). */
magma_clarfg_gpu(m-rk, A(rk, k), A(rk + 1, k), &tau[k], &vn1[k], &Aks[k]);
//Akk = *A(rk, k);
//*A(rk, k) = c_one;
//magma_cgetvector( 1, &Aks[k], 1, &Akk, 1 );
/* needed to avoid the race condition */
if (k == 0) magma_csetvector( 1, &c_one, 1, A(rk, k), 1 );
else magma_ccopymatrix( 1, 1, A(offset, 0), 1, A(rk, k), 1 );
/* Compute Kth column of F:
Compute F(K+1:N,K) := tau(K)*A(RK:M,K+1:N)'*A(RK:M,K) on the GPU */
if (k < n-1 || k > 0) magma_cgetvector( 1, &tau[k], 1, &tauk, 1 );
if (k < n-1) {
i__1 = m - rk;
i__2 = n - k - 1;
/* Send the vector to the GPU */
//magma_csetmatrix( i__1, 1, A(rk, k), lda, dA(rk,k), ldda );
/* Multiply on GPU */
// was CALL CGEMV( 'Conjugate transpose', M-RK+1, N-K,
// TAU( K ), A( RK, K+1 ), LDA,
// A( RK, K ), 1,
// CZERO, F( K+1, K ), 1 )
//magma_cgetvector( 1, &tau[k], 1, &tauk, 1 );
magma_cgemv( MagmaConjTrans, m-rk, n-k-1,
tauk, A( rk, k+1 ), lda,
A( rk, k ), 1,
c_zero, F( k+1, k ), 1 );
//magma_cscal( m-rk, tau[k], F( k+1, k), 1 );
//magma_int_t i__3 = nb-k-1;
//magma_int_t i__4 = i__2 - i__3;
//magma_int_t i__5 = nb-k;
//magma_cgemv( MagmaConjTrans, i__1 - i__5, i__2 - i__3,
// tau[k], dA(rk +i__5, k+1+i__3), ldda,
// dA(rk +i__5, k ), ione,
// c_zero, dF(k+1+i__3, k ), ione );
//magma_cgetmatrix_async( i__2-i__3, 1,
// dF(k + 1 +i__3, k), i__2,
// F (k + 1 +i__3, k), i__2, stream );
//blasf77_cgemv( MagmaConjTransStr, &i__1, &i__3,
// &tau[k], A(rk, k+1), &lda,
// A(rk, k ), &ione,
// &c_zero, F(k+1, k ), &ione );
//magma_queue_sync( stream );
//blasf77_cgemv( MagmaConjTransStr, &i__5, &i__4,
// &tau[k], A(rk, k+1+i__3), &lda,
// A(rk, k ), &ione,
// &c_one, F(k+1+i__3, k ), &ione );
}
/* Padding F(1:K,K) with zeros.
for (j = 0; j <= k; ++j) {
magma_csetvector( 1, &c_zero, 1, F(j, k), 1 );
}*/
/* Incremental updating of F:
F(1:N,K) := F(1:N,K) - tau(K)*F(1:N,1:K-1)*A(RK:M,1:K-1)'*A(RK:M,K).
F(1:N,K) := tau(K)*A(RK:M,K+1:N)'*A(RK:M,K) - tau(K)*F(1:N,1:K-1)*A(RK:M,1:K-1)'*A(RK:M,K)
:= tau(K)(A(RK:M,K+1:N)' - F(1:N,1:K-1)*A(RK:M,1:K-1)') A(RK:M,K)
so, F is (updated A)*V */
//if (k > 0 && k < n-1) {
if (k > 0) {
//magma_cgetvector( 1, &tau[k], 1, &tauk, 1 );
z__1 = MAGMA_C_NEGATE( tauk );
#ifdef RIGHT_UPDATE
i__1 = m - offset - nb;
i__2 = k;
magma_cgemv( MagmaConjTrans, i__1, i__2,
z__1, A(offset+nb, 0), lda,
A(offset+nb, k), ione,
c_zero, auxv, ione );
i__1 = k;
magma_cgemv( MagmaNoTrans, n-k-1, i__1,
c_one, F(k+1,0), ldf,
auxv, ione,
c_one, F(k+1,k), ione );
#else
i__1 = m - rk;
i__2 = k;
//blasf77_cgemv( MagmaConjTransStr, &i__1, &i__2,
// &z__1, A(rk, 0), &lda,
// A(rk, k), &ione,
// &c_zero, auxv, &ione );
magma_cgemv( MagmaConjTrans, i__1, i__2,
z__1, A(rk, 0), lda,
A(rk, k), ione,
c_zero, auxv, ione );
//i__1 = k;
//blasf77_cgemv( MagmaNoTransStr, &n, &i__1,
// &c_one, F(0,0), &ldf,
// auxv, &ione,
// &c_one, F(0,k), &ione );
/*magma_cgemv( MagmaNoTrans, n, i__1,
c_one, F(0,0), ldf,
auxv, ione,
c_one, F(0,k), ione );*/
/* I think we only need stricly lower-triangular part :) */
magma_cgemv( MagmaNoTrans, n-k-1, i__2,
c_one, F(k+1,0), ldf,
auxv, ione,
c_one, F(k+1,k), ione );
#endif
}
/* Optimization: On the last iteration start sending F back to the GPU */
/* Update the current row of A:
A(RK,K+1:N) := A(RK,K+1:N) - A(RK,1:K)*F(K+1:N,1:K)'. */
if (k < n-1) {
i__1 = n - k - 1;
i__2 = k + 1;
//blasf77_cgemm( MagmaNoTransStr, MagmaConjTransStr, &ione, &i__1, &i__2,
// &c_neg_one, A(rk, 0 ), &lda,
// F(k+1,0 ), &ldf,
// &c_one, A(rk, k+1), &lda );
#ifdef RIGHT_UPDATE
/* right-looking update of rows, */
magma_cgemm( MagmaNoTrans, MagmaConjTrans, nb-k, i__1, ione,
c_neg_one, A(rk, k ), lda,
F(k+1, k ), ldf,
c_one, A(rk, k+1), lda );
#else
/* left-looking update of rows, *
* since F=A'v with original A, so no right-looking */
magma_cgemm( MagmaNoTrans, MagmaConjTrans, ione, i__1, i__2,
c_neg_one, A(rk, 0 ), lda,
F(k+1,0 ), ldf,
c_one, A(rk, k+1), lda );
#endif
}
/* Update partial column norms. */
if (rk < min(m, n+offset)-1 ) {
magmablas_scnrm2_row_check_adjust(n-k-1, tol3z, &vn1[k+1], &vn2[k+1], A(rk,k+1), lda, lsticcs);
magma_device_sync();
#if defined(PRECISION_d) || defined(PRECISION_z)
magma_sgetvector( 1, &lsticcs[0], 1, &lsticc, 1 );
#else
magma_sgetvector( 1, &lsticcs[0], 1, &lsticc, 1 );
#endif
}
/*if (rk < lastrk) {
for (j = k + 1; j < n; ++j) {
if (vn1[j] != 0.) {
// NOTE: The following 4 lines follow from the analysis in
// Lapack Working Note 176.
temp = MAGMA_C_ABS( *A(rk,j) ) / vn1[j];
temp = max( 0., ((1. + temp) * (1. - temp)) );
d__1 = vn1[j] / vn2[j];
temp2 = temp * (d__1 * d__1);
if (temp2 <= tol3z) {
vn2[j] = (float) lsticc;
lsticc = j;
} else {
vn1[j] *= magma_ssqrt(temp);
}
}
}
}*/
//*A(rk, k) = Akk;
//magma_csetvector( 1, &Akk, 1, A(rk, k), 1 );
//magma_cswap( 1, &Aks[k], 1, A(rk, k), 1 );
++k;
}
magma_ccopymatrix( 1, k, Aks, 1, A(offset, 0), lda+1 );
// leave k as the last column done
--k;
*kb = k + 1;
rk = offset + *kb - 1;
/* Apply the block reflector to the rest of the matrix:
A(OFFSET+KB+1:M,KB+1:N) := A(OFFSET+KB+1:M,KB+1:N) - A(OFFSET+KB+1:M,1:KB)*F(KB+1:N,1:KB)' */
if (*kb < min(n, m - offset)) {
i__1 = m - rk - 1;
i__2 = n - *kb;
/* Send F to the GPU
magma_csetmatrix( i__2, *kb,
F (*kb, 0), ldf,
dF(*kb, 0), i__2 );*/
magma_cgemm( MagmaNoTrans, MagmaConjTrans, i__1, i__2, *kb,
c_neg_one, A(rk+1, 0 ), lda,
F(*kb, 0 ), ldf,
c_one, A(rk+1, *kb), lda );
}
/* Recomputation of difficult columns. */
if ( lsticc > 0 ) {
// printf( " -- recompute dnorms --\n" );
magmablas_scnrm2_check(m-rk-1, n-*kb, A(rk+1,*kb), lda,
&vn1[*kb], lsticcs);
magma_scopymatrix( n-*kb, 1, &vn1[*kb], *kb, &vn2[*kb], *kb);
/*while( lsticc > 0 ) {
itemp = (magma_int_t)(vn2[lsticc] >= 0. ? floor(vn2[lsticc] + .5) : -floor(.5 - vn2[lsticc]));
i__1 = m - rk - 1;
if (lsticc <= nb)
vn1[lsticc] = magma_cblas_scnrm2( i__1, A(rk+1,lsticc), ione );
else {
// Where is the data, CPU or GPU ?
float r1, r2;
r1 = magma_cblas_scnrm2( nb-k, A(rk+1,lsticc), ione );
r2 = magma_scnrm2(m-offset-nb, dA(offset + nb + 1, lsticc), ione);
vn1[lsticc] = magma_ssqrt(r1*r1+r2*r2);
}
// NOTE: The computation of VN1( LSTICC ) relies on the fact that
// SNRM2 does not fail on vectors with norm below the value of SQRT(SLAMCH('S'))
vn2[lsticc] = vn1[lsticc];
lsticc = itemp;*/
}
magma_free(Aks);
magma_free(lsticcs);
return MAGMA_SUCCESS;
} /* magma_claqps */
/**
Purpose
-------
CLAHR2 reduces the first NB columns of a complex general n-BY-(n-k+1)
matrix A so that elements below the k-th subdiagonal are zero. The
reduction is performed by an orthogonal similarity transformation
Q' * A * Q. The routine returns the matrices V and T which determine
Q as a block reflector I - V*T*V', and also the matrix Y = A * V.
(Note this is different than LAPACK, which computes Y = A * V * T.)
This is an auxiliary routine called by CGEHRD.
Arguments
---------
@param[in]
n INTEGER
The order of the matrix A.
@param[in]
k INTEGER
The offset for the reduction. Elements below the k-th
subdiagonal in the first NB columns are reduced to zero.
K < N.
@param[in]
nb INTEGER
The number of columns to be reduced.
@param[in,out]
dA COMPLEX array on the GPU, dimension (LDDA,N-K+1)
On entry, the n-by-(n-k+1) general matrix A.
On exit, the elements in rows K:N of the first NB columns are
overwritten with the matrix Y.
@param[in]
ldda INTEGER
The leading dimension of the array dA. LDDA >= max(1,N).
@param[out]
dV COMPLEX array on the GPU, dimension (LDDV, NB)
On exit this n-by-nb array contains the Householder vectors of the transformation.
@param[in]
lddv INTEGER
The leading dimension of the array dV. LDDV >= max(1,N).
@param[in,out]
A COMPLEX array, dimension (LDA,N-K+1)
On entry, the n-by-(n-k+1) general matrix A.
On exit, the elements on and above the k-th subdiagonal in
the first NB columns are overwritten with the corresponding
elements of the reduced matrix; the elements below the k-th
subdiagonal, with the array TAU, represent the matrix Q as a
product of elementary reflectors. The other columns of A are
unchanged. See Further Details.
@param[in]
lda INTEGER
The leading dimension of the array A. LDA >= max(1,N).
@param[out]
tau COMPLEX array, dimension (NB)
The scalar factors of the elementary reflectors. See Further
Details.
@param[out]
T COMPLEX array, dimension (LDT,NB)
The upper triangular matrix T.
@param[in]
ldt INTEGER
The leading dimension of the array T. LDT >= NB.
@param[out]
Y COMPLEX array, dimension (LDY,NB)
The n-by-nb matrix Y.
@param[in]
ldy INTEGER
The leading dimension of the array Y. LDY >= N.
Further Details
---------------
The matrix Q is represented as a product of nb elementary reflectors
Q = H(1) H(2) . . . H(nb).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a complex scalar, and v is a complex vector with
v(1:i+k-1) = 0, v(i+k) = 1; v(i+k+1:n) is stored on exit in
A(i+k+1:n,i), and tau in TAU(i).
The elements of the vectors v together form the (n-k+1)-by-nb matrix
V which is needed, with T and Y, to apply the transformation to the
unreduced part of the matrix, using an update of the form:
A := (I - V*T*V') * (A - Y*T*V').
The contents of A on exit are illustrated by the following example
with n = 7, k = 3 and nb = 2:
@verbatim
( a a a a a )
( a a a a a )
( a a a a a )
( h h a a a )
( v1 h a a a )
( v1 v2 a a a )
( v1 v2 a a a )
@endverbatim
where "a" denotes an element of the original matrix A, h denotes a
modified element of the upper Hessenberg matrix H, and vi denotes an
element of the vector defining H(i).
This implementation follows the hybrid algorithm and notations described in
S. Tomov and J. Dongarra, "Accelerating the reduction to upper Hessenberg
form through hybrid GPU-based computing," University of Tennessee Computer
Science Technical Report, UT-CS-09-642 (also LAPACK Working Note 219),
May 24, 2009.
@ingroup magma_cgeev_aux
********************************************************************/
extern "C" magma_int_t
magma_clahr2(
magma_int_t n, magma_int_t k, magma_int_t nb,
magmaFloatComplex_ptr dA, magma_int_t ldda,
magmaFloatComplex_ptr dV, magma_int_t lddv,
magmaFloatComplex *A, magma_int_t lda,
magmaFloatComplex *tau,
magmaFloatComplex *T, magma_int_t ldt,
magmaFloatComplex *Y, magma_int_t ldy )
{
#define A(i_,j_) ( A + (i_) + (j_)*lda)
#define Y(i_,j_) ( Y + (i_) + (j_)*ldy)
#define T(i_,j_) ( T + (i_) + (j_)*ldt)
#define dA(i_,j_) (dA + (i_) + (j_)*ldda)
#define dV(i_,j_) (dV + (i_) + (j_)*lddv)
magmaFloatComplex c_zero = MAGMA_C_ZERO;
magmaFloatComplex c_one = MAGMA_C_ONE;
magmaFloatComplex c_neg_one = MAGMA_C_NEG_ONE;
magma_int_t ione = 1;
magma_int_t n_k_i_1, n_k;
magmaFloatComplex scale;
magma_int_t i;
magmaFloatComplex ei = MAGMA_C_ZERO;
magma_int_t info = 0;
if (n < 0) {
info = -1;
} else if (k < 0 || k > n) {
info = -2;
} else if (nb < 1 || nb > n) {
info = -3;
} else if (ldda < max(1,n)) {
info = -5;
} else if (lddv < max(1,n)) {
info = -7;
} else if (lda < max(1,n)) {
info = -9;
} else if (ldt < max(1,nb)) {
info = -12;
} else if (ldy < max(1,n)) {
info = -13;
}
if (info != 0) {
magma_xerbla( __func__, -(info) );
return info;
}
// adjust from 1-based indexing
k -= 1;
if (n <= 1)
return info;
for (i = 0; i < nb; ++i) {
n_k_i_1 = n - k - i - 1;
n_k = n - k;
if (i > 0) {
// Update A(k:n-1,i); Update i-th column of A - Y * T * V'
// This updates one more row than LAPACK does (row k),
// making the block above the panel an even multiple of nb.
// Use last column of T as workspace, w.
// w(0:i-1, nb-1) = VA(k+i, 0:i-1)'
blasf77_ccopy( &i,
A(k+i,0), &lda,
T(0,nb-1), &ione );
#if defined(PRECISION_z) || defined(PRECISION_c)
// If complex, conjugate row of V.
lapackf77_clacgv(&i, T(0,nb-1), &ione);
#endif
// w = T(0:i-1, 0:i-1) * w
blasf77_ctrmv( "Upper", "No trans", "No trans", &i,
T(0,0), &ldt,
T(0,nb-1), &ione );
// A(k:n-1, i) -= Y(k:n-1, 0:i-1) * w
blasf77_cgemv( "No trans", &n_k, &i,
&c_neg_one, Y(k,0), &ldy,
T(0,nb-1), &ione,
&c_one, A(k,i), &ione );
// Apply I - V * T' * V' to this column (call it b) from the
// left, using the last column of T as workspace, w.
//
// Let V = ( V1 ) and b = ( b1 ) (first i-1 rows)
// ( V2 ) ( b2 )
// where V1 is unit lower triangular
// w := b1 = A(k+1:k+i, i)
blasf77_ccopy( &i,
A(k+1,i), &ione,
T(0,nb-1), &ione );
// w := V1' * b1 = VA(k+1:k+i, 0:i-1)' * w
blasf77_ctrmv( "Lower", "Conj", "Unit", &i,
A(k+1,0), &lda,
T(0,nb-1), &ione );
// w := w + V2'*b2 = w + VA(k+i+1:n-1, 0:i-1)' * A(k+i+1:n-1, i)
blasf77_cgemv( "Conj", &n_k_i_1, &i,
&c_one, A(k+i+1,0), &lda,
A(k+i+1,i), &ione,
&c_one, T(0,nb-1), &ione );
// w := T'*w = T(0:i-1, 0:i-1)' * w
blasf77_ctrmv( "Upper", "Conj", "Non-unit", &i,
T(0,0), &ldt,
T(0,nb-1), &ione );
// b2 := b2 - V2*w = A(k+i+1:n-1, i) - VA(k+i+1:n-1, 0:i-1) * w
blasf77_cgemv( "No trans", &n_k_i_1, &i,
&c_neg_one, A(k+i+1,0), &lda,
T(0,nb-1), &ione,
&c_one, A(k+i+1,i), &ione );
// w := V1*w = VA(k+1:k+i, 0:i-1) * w
blasf77_ctrmv( "Lower", "No trans", "Unit", &i,
A(k+1,0), &lda,
T(0,nb-1), &ione );
// b1 := b1 - w = A(k+1:k+i-1, i) - w
blasf77_caxpy( &i,
&c_neg_one, T(0,nb-1), &ione,
A(k+1,i), &ione );
// Restore diagonal element, saved below during previous iteration
*A(k+i,i-1) = ei;
}
// Generate the elementary reflector H(i) to annihilate A(k+i+1:n-1,i)
lapackf77_clarfg( &n_k_i_1,
A(k+i+1,i),
A(k+i+2,i), &ione, &tau[i] );
// Save diagonal element and set to one, to simplify multiplying by V
ei = *A(k+i+1,i);
*A(k+i+1,i) = c_one;
// dV(i+1:n-k-1, i) = VA(k+i+1:n-1, i)
magma_csetvector( n_k_i_1,
A(k+i+1,i), 1,
dV(i+1,i), 1 );
// Compute Y(k+1:n,i) = A vi
// dA(k:n-1, i) = dA(k:n-1, i+1:n-k-1) * dV(i+1:n-k-1, i)
magma_cgemv( MagmaNoTrans, n_k, n_k_i_1,
c_one, dA(k,i+1), ldda,
dV(i+1,i), ione,
c_zero, dA(k,i), ione );
// Compute T(0:i,i) = [ -tau T V' vi ]
// [ tau ]
// T(0:i-1, i) = -tau VA(k+i+1:n-1, 0:i-1)' VA(k+i+1:n-1, i)
scale = MAGMA_C_NEGATE( tau[i]);
blasf77_cgemv( "Conj", &n_k_i_1, &i,
&scale, A(k+i+1,0), &lda,
A(k+i+1,i), &ione,
&c_zero, T(0,i), &ione );
// T(0:i-1, i) = T(0:i-1, 0:i-1) * T(0:i-1, i)
blasf77_ctrmv( "Upper", "No trans", "Non-unit", &i,
T(0,0), &ldt,
T(0,i), &ione );
*T(i,i) = tau[i];
// Y(k:n-1, i) = dA(k:n-1, i)
magma_cgetvector( n-k,
dA(k,i), 1,
Y(k,i), 1 );
}
// Restore diagonal element
*A(k+nb,nb-1) = ei;
return info;
} /* magma_clahr2 */
/***************************************************************************//**
Purpose
-------
CLAQPS computes a step of QR factorization with column pivoting
of a complex M-by-N matrix A by using Blas-3. It tries to factorize
NB columns from A starting from the row OFFSET+1, and updates all
of the matrix with Blas-3 xGEMM.
In some cases, due to catastrophic cancellations, it cannot
factorize NB columns. Hence, the actual number of factorized
columns is returned in KB.
Block A(1:OFFSET,1:N) is accordingly pivoted, but not factorized.
Arguments
---------
@param[in]
m INTEGER
The number of rows of the matrix A. M >= 0.
@param[in]
n INTEGER
The number of columns of the matrix A. N >= 0
@param[in]
offset INTEGER
The number of rows of A that have been factorized in
previous steps.
@param[in]
nb INTEGER
The number of columns to factorize.
@param[out]
kb INTEGER
The number of columns actually factorized.
@param[in,out]
A COMPLEX array, dimension (LDA,N)
On entry, the M-by-N matrix A.
On exit, block A(OFFSET+1:M,1:KB) is the triangular
factor obtained and block A(1:OFFSET,1:N) has been
accordingly pivoted, but no factorized.
The rest of the matrix, block A(OFFSET+1:M,KB+1:N) has
been updated.
@param[in]
lda INTEGER
The leading dimension of the array A. LDA >= max(1,M).
@param[in,out]
dA COMPLEX array, dimension (LDA,N)
Copy of A on the GPU.
Portions of A are updated on the CPU;
portions of dA are updated on the GPU. See code for details.
@param[in]
ldda INTEGER
The leading dimension of the array dA. LDDA >= max(1,M).
@param[in,out]
jpvt INTEGER array, dimension (N)
JPVT(I) = K <==> Column K of the full matrix A has been
permuted into position I in AP.
@param[out]
tau COMPLEX array, dimension (KB)
The scalar factors of the elementary reflectors.
@param[in,out]
vn1 REAL array, dimension (N)
The vector with the partial column norms.
@param[in,out]
vn2 REAL array, dimension (N)
The vector with the exact column norms.
@param[in,out]
auxv COMPLEX array, dimension (NB)
Auxiliar vector.
@param[in,out]
F COMPLEX array, dimension (LDF,NB)
Matrix F' = L*Y'*A.
@param[in]
ldf INTEGER
The leading dimension of the array F. LDF >= max(1,N).
@param[in,out]
dF COMPLEX array, dimension (LDDF,NB)
Copy of F on the GPU. See code for details.
@param[in]
lddf INTEGER
The leading dimension of the array dF. LDDF >= max(1,N).
@ingroup magma_laqps
*******************************************************************************/
extern "C" magma_int_t
magma_claqps(
magma_int_t m, magma_int_t n, magma_int_t offset,
magma_int_t nb, magma_int_t *kb,
magmaFloatComplex *A, magma_int_t lda,
magmaFloatComplex_ptr dA, magma_int_t ldda,
magma_int_t *jpvt, magmaFloatComplex *tau, float *vn1, float *vn2,
magmaFloatComplex *auxv,
magmaFloatComplex *F, magma_int_t ldf,
magmaFloatComplex_ptr dF, magma_int_t lddf)
{
#define A(i, j) (A + (i) + (j)*(lda ))
#define dA(i, j) (dA + (i) + (j)*(ldda))
#define F(i, j) (F + (i) + (j)*(ldf ))
#define dF(i, j) (dF + (i) + (j)*(lddf))
magmaFloatComplex c_zero = MAGMA_C_MAKE( 0.,0.);
magmaFloatComplex c_one = MAGMA_C_MAKE( 1.,0.);
magmaFloatComplex c_neg_one = MAGMA_C_MAKE(-1.,0.);
magma_int_t ione = 1;
magma_int_t i__1, i__2;
float d__1;
magmaFloatComplex z__1;
magma_int_t j, k, rk;
magmaFloatComplex Akk;
magma_int_t pvt;
float temp, temp2, tol3z;
magma_int_t itemp;
magma_int_t lsticc;
magma_int_t lastrk;
lastrk = min( m, n + offset );
tol3z = magma_ssqrt( lapackf77_slamch("Epsilon"));
magma_queue_t queue;
magma_device_t cdev;
magma_getdevice( &cdev );
magma_queue_create( cdev, &queue );
lsticc = 0;
k = 0;
while( k < nb && lsticc == 0 ) {
rk = offset + k;
/* Determine ith pivot column and swap if necessary */
// subtract 1 from Fortran isamax; pvt, k are 0-based.
i__1 = n-k;
pvt = k + blasf77_isamax( &i__1, &vn1[k], &ione ) - 1;
if (pvt != k) {
if (pvt >= nb) {
/* 1. Start copy from GPU */
magma_cgetmatrix_async( m - offset - nb, 1,
dA(offset + nb, pvt), ldda,
A (offset + nb, pvt), lda, queue );
}
/* F gets swapped so F must be sent at the end to GPU */
i__1 = k;
blasf77_cswap( &i__1, F(pvt,0), &ldf, F(k,0), &ldf );
itemp = jpvt[pvt];
jpvt[pvt] = jpvt[k];
jpvt[k] = itemp;
vn1[pvt] = vn1[k];
vn2[pvt] = vn2[k];
if (pvt < nb) {
/* no need of transfer if pivot is within the panel */
blasf77_cswap( &m, A(0, pvt), &ione, A(0, k), &ione );
}
else {
/* 1. Finish copy from GPU */
magma_queue_sync( queue );
/* 2. Swap as usual on CPU */
blasf77_cswap(&m, A(0, pvt), &ione, A(0, k), &ione);
/* 3. Restore the GPU */
magma_csetmatrix_async( m - offset - nb, 1,
A (offset + nb, pvt), lda,
dA(offset + nb, pvt), ldda, queue );
}
}
/* Apply previous Householder reflectors to column K:
A(RK:M,K) := A(RK:M,K) - A(RK:M,1:K-1)*F(K,1:K-1)'.
Optimization: multiply with beta=0; wait for vector and subtract */
if (k > 0) {
#ifdef COMPLEX
for (j = 0; j < k; ++j) {
*F(k,j) = MAGMA_C_CONJ( *F(k,j) );
}
#endif
i__1 = m - rk;
i__2 = k;
blasf77_cgemv( MagmaNoTransStr, &i__1, &i__2,
&c_neg_one, A(rk, 0), &lda,
F(k, 0), &ldf,
&c_one, A(rk, k), &ione );
#ifdef COMPLEX
for (j = 0; j < k; ++j) {
*F(k,j) = MAGMA_C_CONJ( *F(k,j) );
}
#endif
}
/* Generate elementary reflector H(k). */
if (rk < m-1) {
i__1 = m - rk;
lapackf77_clarfg( &i__1, A(rk, k), A(rk + 1, k), &ione, &tau[k] );
} else {
lapackf77_clarfg( &ione, A(rk, k), A(rk, k), &ione, &tau[k] );
}
Akk = *A(rk, k);
*A(rk, k) = c_one;
/* Compute Kth column of F:
Compute F(K+1:N,K) := tau(K)*A(RK:M,K+1:N)'*A(RK:M,K) on the GPU */
if (k < n-1) {
i__1 = m - rk;
i__2 = n - k - 1;
/* Send the vector to the GPU */
magma_csetmatrix( i__1, 1, A(rk, k), lda, dA(rk,k), ldda, queue );
/* Multiply on GPU */
// was CALL CGEMV( 'Conjugate transpose', M-RK+1, N-K,
// TAU( K ), A( RK, K+1 ), LDA,
// A( RK, K ), 1,
// CZERO, F( K+1, K ), 1 )
magma_int_t i__3 = nb-k-1;
magma_int_t i__4 = i__2 - i__3;
magma_int_t i__5 = nb-k;
magma_cgemv( MagmaConjTrans, i__1 - i__5, i__2 - i__3,
tau[k], dA(rk +i__5, k+1+i__3), ldda,
dA(rk +i__5, k ), ione,
c_zero, dF(k+1+i__3, k ), ione, queue );
magma_cgetmatrix_async( i__2-i__3, 1,
dF(k + 1 +i__3, k), i__2,
F (k + 1 +i__3, k), i__2, queue );
blasf77_cgemv( MagmaConjTransStr, &i__1, &i__3,
&tau[k], A(rk, k+1), &lda,
A(rk, k ), &ione,
&c_zero, F(k+1, k ), &ione );
magma_queue_sync( queue );
blasf77_cgemv( MagmaConjTransStr, &i__5, &i__4,
&tau[k], A(rk, k+1+i__3), &lda,
A(rk, k ), &ione,
&c_one, F(k+1+i__3, k ), &ione );
}
/* Padding F(1:K,K) with zeros. */
for (j = 0; j < k; ++j) {
*F(j, k) = c_zero;
}
/* Incremental updating of F:
F(1:N,K) := F(1:N,K) - tau(K)*F(1:N,1:K-1)*A(RK:M,1:K-1)'*A(RK:M,K). */
if (k > 0) {
i__1 = m - rk;
i__2 = k;
z__1 = MAGMA_C_NEGATE( tau[k] );
blasf77_cgemv( MagmaConjTransStr, &i__1, &i__2,
&z__1, A(rk, 0), &lda,
A(rk, k), &ione,
&c_zero, auxv, &ione );
i__1 = k;
blasf77_cgemv( MagmaNoTransStr, &n, &i__1,
&c_one, F(0,0), &ldf,
auxv, &ione,
&c_one, F(0,k), &ione );
}
/* Optimization: On the last iteration start sending F back to the GPU */
/* Update the current row of A:
A(RK,K+1:N) := A(RK,K+1:N) - A(RK,1:K)*F(K+1:N,1:K)'. */
if (k < n-1) {
i__1 = n - k - 1;
i__2 = k + 1;
blasf77_cgemm( MagmaNoTransStr, MagmaConjTransStr, &ione, &i__1, &i__2,
&c_neg_one, A(rk, 0 ), &lda,
F(k+1,0 ), &ldf,
&c_one, A(rk, k+1), &lda );
}
/* Update partial column norms. */
if (rk < lastrk) {
for (j = k + 1; j < n; ++j) {
if (vn1[j] != 0.) {
/* NOTE: The following 4 lines follow from the analysis in
Lapack Working Note 176. */
temp = MAGMA_C_ABS( *A(rk,j) ) / vn1[j];
temp = max( 0., ((1. + temp) * (1. - temp)) );
d__1 = vn1[j] / vn2[j];
temp2 = temp * (d__1 * d__1);
if (temp2 <= tol3z) {
vn2[j] = (float) lsticc;
lsticc = j;
} else {
vn1[j] *= magma_ssqrt(temp);
}
}
}
}
*A(rk, k) = Akk;
++k;
}
// leave k as the last column done
--k;
*kb = k + 1;
rk = offset + *kb - 1;
/* Apply the block reflector to the rest of the matrix:
A(OFFSET+KB+1:M,KB+1:N) := A(OFFSET+KB+1:M,KB+1:N) - A(OFFSET+KB+1:M,1:KB)*F(KB+1:N,1:KB)' */
if (*kb < min(n, m - offset)) {
i__1 = m - rk - 1;
i__2 = n - *kb;
/* Send F to the GPU */
magma_csetmatrix( i__2, *kb,
F (*kb, 0), ldf,
dF(*kb, 0), i__2, queue );
magma_cgemm( MagmaNoTrans, MagmaConjTrans, i__1, i__2, *kb,
c_neg_one, dA(rk+1, 0 ), ldda,
dF(*kb, 0 ), i__2,
c_one, dA(rk+1, *kb), ldda, queue );
}
/* Recomputation of difficult columns. */
while( lsticc > 0 ) {
itemp = (magma_int_t)(vn2[lsticc] >= 0. ? floor(vn2[lsticc] + .5) : -floor(.5 - vn2[lsticc]));
i__1 = m - rk - 1;
if (lsticc <= nb) {
vn1[lsticc] = magma_cblas_scnrm2( i__1, A(rk+1,lsticc), ione );
}
else {
/* Where is the data, CPU or GPU ? */
float r1, r2;
r1 = magma_cblas_scnrm2( nb-k, A(rk+1,lsticc), ione );
r2 = magma_scnrm2( m-offset-nb, dA(offset + nb + 1, lsticc), ione, queue );
//vn1[lsticc] = magma_scnrm2( i__1, dA(rk + 1, lsticc), ione, queue );
vn1[lsticc] = magma_ssqrt(r1*r1 + r2*r2);
}
/* NOTE: The computation of VN1( LSTICC ) relies on the fact that
SNRM2 does not fail on vectors with norm below the value of SQRT(SLAMCH('S')) */
vn2[lsticc] = vn1[lsticc];
lsticc = itemp;
}
magma_queue_destroy( queue );
return MAGMA_SUCCESS;
} /* magma_claqps */
extern "C" magma_int_t
magma_claqps_gpu(magma_int_t m, magma_int_t n, magma_int_t offset,
magma_int_t nb, magma_int_t *kb,
magmaFloatComplex *A, magma_int_t lda,
magma_int_t *jpvt, magmaFloatComplex *tau,
float *vn1, float *vn2,
magmaFloatComplex *auxv,
magmaFloatComplex *F, magma_int_t ldf)
{
/* -- MAGMA (version 1.4.0) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
August 2013
Purpose
=======
CLAQPS computes a step of QR factorization with column pivoting
of a complex M-by-N matrix A by using Blas-3. It tries to factorize
NB columns from A starting from the row OFFSET+1, and updates all
of the matrix with Blas-3 xGEMM.
In some cases, due to catastrophic cancellations, it cannot
factorize NB columns. Hence, the actual number of factorized
columns is returned in KB.
Block A(1:OFFSET,1:N) is accordingly pivoted, but not factorized.
Arguments
=========
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0
OFFSET (input) INTEGER
The number of rows of A that have been factorized in
previous steps.
NB (input) INTEGER
The number of columns to factorize.
KB (output) INTEGER
The number of columns actually factorized.
A (input/output) COMPLEX*16 array, dimension (LDA,N)
On entry, the M-by-N matrix A.
On exit, block A(OFFSET+1:M,1:KB) is the triangular
factor obtained and block A(1:OFFSET,1:N) has been
accordingly pivoted, but no factorized.
The rest of the matrix, block A(OFFSET+1:M,KB+1:N) has
been updated.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,M).
JPVT (input/output) INTEGER array, dimension (N)
JPVT(I) = K <==> Column K of the full matrix A has been
permuted into position I in AP.
TAU (output) COMPLEX*16 array, dimension (KB)
The scalar factors of the elementary reflectors.
VN1 (input/output) DOUBLE PRECISION array, dimension (N)
The vector with the partial column norms.
VN2 (input/output) DOUBLE PRECISION array, dimension (N)
The vector with the exact column norms.
AUXV (input/output) COMPLEX*16 array, dimension (NB)
Auxiliar vector.
F (input/output) COMPLEX*16 array, dimension (LDF,NB)
Matrix F' = L*Y'*A.
LDF (input) INTEGER
The leading dimension of the array F. LDF >= max(1,N).
===================================================================== */
#define A(i, j) (A + (i) + (j)*(lda ))
#define F(i, j) (F + (i) + (j)*(ldf ))
magmaFloatComplex c_zero = MAGMA_C_MAKE( 0.,0.);
magmaFloatComplex c_one = MAGMA_C_MAKE( 1.,0.);
magmaFloatComplex c_neg_one = MAGMA_C_MAKE(-1.,0.);
magma_int_t ione = 1;
magma_int_t i__1, i__2;
//float d__1;
magmaFloatComplex z__1;
//magma_int_t j;
magma_int_t k, rk;
//magmaFloatComplex Akk;
magmaFloatComplex *Aks;
magmaFloatComplex tauk;
magma_int_t pvt;
//float temp, temp2;
float tol3z;
magma_int_t itemp;
float lsticc, *lsticcs;
magma_int_t lastrk;
magma_smalloc( &lsticcs, 1+256*(n+255)/256 );
lastrk = min( m, n + offset );
tol3z = magma_ssqrt( lapackf77_slamch("Epsilon"));
lsticc = 0;
k = 0;
magma_cmalloc( &Aks, nb );
while( k < nb && lsticc == 0 ) {
rk = offset + k;
/* Determine ith pivot column and swap if necessary */
// Fortran: pvt, k, isamax are all 1-based; subtract 1 from k.
// C: pvt, k, isamax are all 0-based; don't subtract 1.
pvt = k - 1 + magma_isamax( n-k, &vn1[k], ione );
if (pvt != k) {
/*if (pvt >= nb) {
// 1. Start copy from GPU
magma_cgetmatrix_async( m - offset - nb, 1,
dA(offset + nb, pvt), ldda,
A (offset + nb, pvt), lda, stream );
}*/
/* F gets swapped so F must be sent at the end to GPU */
i__1 = k;
/*if (pvt < nb){
// no need of transfer if pivot is within the panel
blasf77_cswap( &m, A(0, pvt), &ione, A(0, k), &ione );
}
else {
// 1. Finish copy from GPU
magma_queue_sync( stream );
// 2. Swap as usual on CPU
blasf77_cswap(&m, A(0, pvt), &ione, A(0, k), &ione);
// 3. Restore the GPU
magma_csetmatrix_async( m - offset - nb, 1,
A (offset + nb, pvt), lda,
dA(offset + nb, pvt), ldda, stream);
}*/
magmablas_cswap( m, A(0, pvt), ione, A(0, k), ione );
//blasf77_cswap( &i__1, F(pvt,0), &ldf, F(k,0), &ldf );
magmablas_cswap( i__1, F(pvt, 0), ldf, F(k, 0), ldf);
itemp = jpvt[pvt];
jpvt[pvt] = jpvt[k];
jpvt[k] = itemp;
//vn1[pvt] = vn1[k];
//vn2[pvt] = vn2[k];
#if defined(PRECISION_d) || defined(PRECISION_z)
//magma_dswap( 1, &vn1[pvt], 1, &vn1[k], 1 );
//magma_dswap( 1, &vn2[pvt], 1, &vn2[k], 1 );
magma_dswap( 2, &vn1[pvt], n+offset, &vn1[k], n+offset );
#else
//magma_sswap( 1, &vn1[pvt], 1, &vn1[k], 1 );
//magma_sswap( 1, &vn2[pvt], 1, &vn2[k], 1 );
magma_sswap(2, &vn1[pvt], n+offset, &vn1[k], n+offset);
#endif
}
/* Apply previous Householder reflectors to column K:
A(RK:M,K) := A(RK:M,K) - A(RK:M,1:K-1)*F(K,1:K-1)'.
Optimization: multiply with beta=0; wait for vector and subtract */
if (k > 0) {
/*#if (defined(PRECISION_c) || defined(PRECISION_z))
for (j = 0; j < k; ++j){
*F(k,j) = MAGMA_C_CNJG( *F(k,j) );
}
#endif*/
//#define RIGHT_UPDATE
#ifdef RIGHT_UPDATE
i__1 = m - offset - nb;
i__2 = k;
magma_cgemv( MagmaNoTrans, i__1, i__2,
c_neg_one, A(offset+nb, 0), lda,
F(k, 0), ldf,
c_one, A(offset+nb, k), ione );
#else
i__1 = m - rk;
i__2 = k;
/*blasf77_cgemv( MagmaNoTransStr, &i__1, &i__2,
&c_neg_one, A(rk, 0), &lda,
F(k, 0), &ldf,
&c_one, A(rk, k), &ione );*/
magma_cgemv( MagmaNoTrans, i__1, i__2,
c_neg_one, A(rk, 0), lda,
F(k, 0), ldf,
c_one, A(rk, k), ione );
#endif
/*#if (defined(PRECISION_c) || defined(PRECISION_z))
for (j = 0; j < k; ++j) {
*F(k,j) = MAGMA_C_CNJG( *F(k,j) );
}
#endif*/
}
/* Generate elementary reflector H(k). */
magma_clarfg_gpu(m-rk, A(rk, k), A(rk + 1, k), &tau[k], &vn1[k], &Aks[k]);
//Akk = *A(rk, k);
//*A(rk, k) = c_one;
//magma_cgetvector( 1, &Aks[k], 1, &Akk, 1 );
/* needed to avoid the race condition */
if (k == 0) magma_csetvector( 1, &c_one, 1, A(rk, k), 1 );
else magma_ccopymatrix( 1, 1, A(offset, 0), 1, A(rk, k), 1 );
/* Compute Kth column of F:
Compute F(K+1:N,K) := tau(K)*A(RK:M,K+1:N)'*A(RK:M,K) on the GPU */
if (k < n-1 || k > 0) magma_cgetvector( 1, &tau[k], 1, &tauk, 1 );
if (k < n-1) {
i__1 = m - rk;
i__2 = n - k - 1;
/* Send the vector to the GPU */
//magma_csetmatrix( i__1, 1, A(rk, k), lda, dA(rk,k), ldda );
/* Multiply on GPU */
// was CALL CGEMV( 'Conjugate transpose', M-RK+1, N-K,
// TAU( K ), A( RK, K+1 ), LDA,
// A( RK, K ), 1,
// CZERO, F( K+1, K ), 1 )
//magma_cgetvector( 1, &tau[k], 1, &tauk, 1 );
magma_cgemv( MagmaConjTrans, m-rk, n-k-1,
tauk, A( rk, k+1 ), lda,
A( rk, k ), 1,
c_zero, F( k+1, k ), 1 );
//magma_cscal( m-rk, tau[k], F( k+1, k), 1 );
//magma_int_t i__3 = nb-k-1;
//magma_int_t i__4 = i__2 - i__3;
//magma_int_t i__5 = nb-k;
//magma_cgemv( MagmaConjTrans, i__1 - i__5, i__2 - i__3,
// tau[k], dA(rk +i__5, k+1+i__3), ldda,
// dA(rk +i__5, k ), ione,
// c_zero, dF(k+1+i__3, k ), ione );
//magma_cgetmatrix_async( i__2-i__3, 1,
// dF(k + 1 +i__3, k), i__2,
// F (k + 1 +i__3, k), i__2, stream );
//blasf77_cgemv( MagmaConjTransStr, &i__1, &i__3,
// &tau[k], A(rk, k+1), &lda,
// A(rk, k ), &ione,
// &c_zero, F(k+1, k ), &ione );
//magma_queue_sync( stream );
//blasf77_cgemv( MagmaConjTransStr, &i__5, &i__4,
// &tau[k], A(rk, k+1+i__3), &lda,
// A(rk, k ), &ione,
// &c_one, F(k+1+i__3, k ), &ione );
}
/* Padding F(1:K,K) with zeros.
for (j = 0; j <= k; ++j) {
magma_csetvector( 1, &c_zero, 1, F(j, k), 1 );
}*/
/* Incremental updating of F:
F(1:N,K) := F(1:N,K) - tau(K)*F(1:N,1:K-1)*A(RK:M,1:K-1)'*A(RK:M,K).
F(1:N,K) := tau(K)*A(RK:M,K+1:N)'*A(RK:M,K) - tau(K)*F(1:N,1:K-1)*A(RK:M,1:K-1)'*A(RK:M,K)
:= tau(K)(A(RK:M,K+1:N)' - F(1:N,1:K-1)*A(RK:M,1:K-1)') A(RK:M,K)
so, F is (updated A)*V */
//if (k > 0 && k<n-1) {
if (k > 0) {
//magma_cgetvector( 1, &tau[k], 1, &tauk, 1 );
z__1 = MAGMA_C_NEGATE( tauk );
#ifdef RIGHT_UPDATE
i__1 = m - offset - nb;
i__2 = k;
magma_cgemv( MagmaConjTrans, i__1, i__2,
z__1, A(offset+nb, 0), lda,
A(offset+nb, k), ione,
c_zero, auxv, ione );
i__1 = k;
magma_cgemv( MagmaNoTrans, n-k-1, i__1,
c_one, F(k+1,0), ldf,
auxv, ione,
c_one, F(k+1,k), ione );
#else
i__1 = m - rk;
i__2 = k;
//blasf77_cgemv( MagmaConjTransStr, &i__1, &i__2,
// &z__1, A(rk, 0), &lda,
// A(rk, k), &ione,
// &c_zero, auxv, &ione );
magma_cgemv( MagmaConjTrans, i__1, i__2,
z__1, A(rk, 0), lda,
A(rk, k), ione,
c_zero, auxv, ione );
//i__1 = k;
//blasf77_cgemv( MagmaNoTransStr, &n, &i__1,
// &c_one, F(0,0), &ldf,
// auxv, &ione,
// &c_one, F(0,k), &ione );
/*magma_cgemv( MagmaNoTrans, n, i__1,
c_one, F(0,0), ldf,
auxv, ione,
c_one, F(0,k), ione );*/
/* I think we only need stricly lower-triangular part :) */
magma_cgemv( MagmaNoTrans, n-k-1, i__2,
c_one, F(k+1,0), ldf,
auxv, ione,
c_one, F(k+1,k), ione );
#endif
}
/* Optimization: On the last iteration start sending F back to the GPU */
/* Update the current row of A:
A(RK,K+1:N) := A(RK,K+1:N) - A(RK,1:K)*F(K+1:N,1:K)'. */
if (k < n-1) {
i__1 = n - k - 1;
i__2 = k + 1;
//blasf77_cgemm( MagmaNoTransStr, MagmaConjTransStr, &ione, &i__1, &i__2,
// &c_neg_one, A(rk, 0 ), &lda,
// F(k+1,0 ), &ldf,
// &c_one, A(rk, k+1), &lda );
#ifdef RIGHT_UPDATE
/* right-looking update of rows, */
magma_cgemm( MagmaNoTrans, MagmaConjTrans, nb-k, i__1, ione,
c_neg_one, A(rk, k ), lda,
F(k+1, k ), ldf,
c_one, A(rk, k+1), lda );
#else
/* left-looking update of rows, *
* since F=A'v with original A, so no right-looking */
magma_cgemm( MagmaNoTrans, MagmaConjTrans, ione, i__1, i__2,
c_neg_one, A(rk, 0 ), lda,
F(k+1,0 ), ldf,
c_one, A(rk, k+1), lda );
#endif
}
/* Update partial column norms. */
if (rk < min(m, n+offset)-1 ){
magmablas_scnrm2_row_check_adjust(n-k-1, tol3z, &vn1[k+1], &vn2[k+1], A(rk,k+1), lda, lsticcs);
magma_device_sync();
#if defined(PRECISION_d) || defined(PRECISION_z)
magma_dgetvector( 1, &lsticcs[0], 1, &lsticc, 1 );
#else
magma_sgetvector( 1, &lsticcs[0], 1, &lsticc, 1 );
#endif
}
/*if (rk < lastrk) {
for (j = k + 1; j < n; ++j) {
if (vn1[j] != 0.) {
// NOTE: The following 4 lines follow from the analysis in
// Lapack Working Note 176.
temp = MAGMA_C_ABS( *A(rk,j) ) / vn1[j];
temp = max( 0., ((1. + temp) * (1. - temp)) );
d__1 = vn1[j] / vn2[j];
temp2 = temp * (d__1 * d__1);
if (temp2 <= tol3z) {
vn2[j] = (float) lsticc;
lsticc = j;
} else {
vn1[j] *= magma_ssqrt(temp);
}
}
}
}*/
//*A(rk, k) = Akk;
//magma_csetvector( 1, &Akk, 1, A(rk, k), 1 );
//magma_cswap( 1, &Aks[k], 1, A(rk, k), 1 );
++k;
}
magma_ccopymatrix( 1, k, Aks, 1, A(offset, 0), lda+1 );
// leave k as the last column done
--k;
*kb = k + 1;
rk = offset + *kb - 1;
/* Apply the block reflector to the rest of the matrix:
A(OFFSET+KB+1:M,KB+1:N) := A(OFFSET+KB+1:M,KB+1:N) - A(OFFSET+KB+1:M,1:KB)*F(KB+1:N,1:KB)' */
if (*kb < min(n, m - offset)) {
i__1 = m - rk - 1;
i__2 = n - *kb;
/* Send F to the GPU
magma_csetmatrix( i__2, *kb,
F (*kb, 0), ldf,
dF(*kb, 0), i__2 );*/
magma_cgemm( MagmaNoTrans, MagmaConjTrans, i__1, i__2, *kb,
c_neg_one, A(rk+1, 0 ), lda,
F(*kb, 0 ), ldf,
c_one, A(rk+1, *kb), lda );
}
/* Recomputation of difficult columns. */
if( lsticc > 0 ) {
printf( " -- recompute dnorms --\n" );
magmablas_scnrm2_check(m-rk-1, n-*kb, A(rk+1,*kb), lda,
&vn1[*kb], lsticcs);
#if defined(PRECISION_d) || defined(PRECISION_z)
magma_dcopymatrix( n-*kb, 1, &vn1[*kb], *kb, &vn2[*kb], *kb);
#else
magma_scopymatrix( n-*kb, 1, &vn1[*kb], *kb, &vn2[*kb], *kb);
#endif
/*while( lsticc > 0 ) {
itemp = (magma_int_t)(vn2[lsticc] >= 0. ? floor(vn2[lsticc] + .5) : -floor(.5 - vn2[lsticc]));
i__1 = m - rk - 1;
if (lsticc <= nb)
vn1[lsticc] = cblas_scnrm2(i__1, A(rk + 1, lsticc), ione);
else {
// Where is the data, CPU or GPU ?
float r1, r2;
r1 = cblas_scnrm2(nb-k, A(rk + 1, lsticc), ione);
r2 = magma_scnrm2(m-offset-nb, dA(offset + nb + 1, lsticc), ione);
vn1[lsticc] = magma_ssqrt(r1*r1+r2*r2);
}
// NOTE: The computation of VN1( LSTICC ) relies on the fact that
// SNRM2 does not fail on vectors with norm below the value of SQRT(SLAMCH('S'))
vn2[lsticc] = vn1[lsticc];
lsticc = itemp;*/
}
magma_free(Aks);
magma_free(lsticcs);
return MAGMA_SUCCESS;
} /* magma_claqps */
/**
Purpose
-------
CLAHR2 reduces the first NB columns of a complex general n-BY-(n-k+1)
matrix A so that elements below the k-th subdiagonal are zero. The
reduction is performed by an orthogonal similarity transformation
Q' * A * Q. The routine returns the matrices V and T which determine
Q as a block reflector I - V*T*V', and also the matrix Y = A * V.
(Note this is different than LAPACK, which computes Y = A * V * T.)
This is an auxiliary routine called by CGEHRD.
Arguments
---------
@param[in]
n INTEGER
The order of the matrix A.
@param[in]
k INTEGER
The offset for the reduction. Elements below the k-th
subdiagonal in the first NB columns are reduced to zero.
K < N.
@param[in]
nb INTEGER
The number of columns to be reduced.
@param[in,out]
A COMPLEX array, dimension (LDA,N-K+1)
On entry, the n-by-(n-k+1) general matrix A.
On exit, the elements on and above the k-th subdiagonal in
the first NB columns are overwritten with the corresponding
elements of the reduced matrix; the elements below the k-th
subdiagonal, with the array TAU, represent the matrix Q as a
product of elementary reflectors. The other columns of A are
unchanged. See Further Details.
@param[in]
lda INTEGER
The leading dimension of the array A. LDA >= max(1,N).
@param[out]
tau COMPLEX array, dimension (NB)
The scalar factors of the elementary reflectors. See Further
Details.
@param[out]
T COMPLEX array, dimension (LDT,NB)
The upper triangular matrix T.
@param[in]
ldt INTEGER
The leading dimension of the array T. LDT >= NB.
@param[out]
Y COMPLEX array, dimension (LDY,NB)
The n-by-nb matrix Y.
@param[in]
ldy INTEGER
The leading dimension of the array Y. LDY >= N.
@param[in,out]
data Structure with pointers to dA, dT, dV, dW, dY
which are distributed across multiple GPUs.
Further Details
---------------
The matrix Q is represented as a product of nb elementary reflectors
Q = H(1) H(2) . . . H(nb).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a complex scalar, and v is a complex vector with
v(1:i+k-1) = 0, v(i+k) = 1; v(i+k+1:n) is stored on exit in
A(i+k+1:n,i), and tau in TAU(i).
The elements of the vectors v together form the (n-k+1)-by-nb matrix
V which is needed, with T and Y, to apply the transformation to the
unreduced part of the matrix, using an update of the form:
A := (I - V*T*V') * (A - Y*T*V').
The contents of A on exit are illustrated by the following example
with n = 7, k = 3 and nb = 2:
@verbatim
( a a a a a )
( a a a a a )
( a a a a a )
( h h a a a )
( v1 h a a a )
( v1 v2 a a a )
( v1 v2 a a a )
@endverbatim
where "a" denotes an element of the original matrix A, h denotes a
modified element of the upper Hessenberg matrix H, and vi denotes an
element of the vector defining H(i).
This implementation follows the hybrid algorithm and notations described in
S. Tomov and J. Dongarra, "Accelerating the reduction to upper Hessenberg
form through hybrid GPU-based computing," University of Tennessee Computer
Science Technical Report, UT-CS-09-642 (also LAPACK Working Note 219),
May 24, 2009.
@ingroup magma_cgeev_aux
********************************************************************/
extern "C" magma_int_t
magma_clahr2_m(
magma_int_t n, magma_int_t k, magma_int_t nb,
magmaFloatComplex *A, magma_int_t lda,
magmaFloatComplex *tau,
magmaFloatComplex *T, magma_int_t ldt,
magmaFloatComplex *Y, magma_int_t ldy,
struct cgehrd_data *data )
{
#define A( i, j ) ( A + (i) + (j)*lda)
#define Y( i, j ) ( Y + (i) + (j)*ldy)
#define T( i, j ) ( T + (i) + (j)*ldt)
#define dA( d, i, j ) (data->A [d] + (i) + (j)*ldda)
#define dTi( d ) (data->Ti[d])
#define dV( d, i, j ) (data->V [d] + (i) + (j)*ldv )
#define dVd( d, i, j ) (data->Vd[d] + (i) + (j)*ldvd)
#define dY( d, i, j ) (data->Y [d] + (i) + (j)*ldda)
magmaFloatComplex c_zero = MAGMA_C_ZERO;
magmaFloatComplex c_one = MAGMA_C_ONE;
magmaFloatComplex c_neg_one = MAGMA_C_NEG_ONE;
magmaFloatComplex tmp;
magma_int_t ngpu = data->ngpu;
magma_int_t ldda = data->ldda;
magma_int_t ldv = data->ldv;
magma_int_t ldvd = data->ldvd;
magma_int_t ione = 1;
magma_int_t d, dki1, dn, nblocks, gblock, lblock, lgid;
magma_int_t n_k_i_1, n_k;
magmaFloatComplex scale;
magma_int_t i;
magmaFloatComplex ei = MAGMA_C_ZERO;
magma_int_t info_data = 0;
magma_int_t *info = &info_data;
if (n < 0) {
*info = -1;
} else if (k < 0 || k >= n) {
*info = -2;
} else if (nb < 1 || nb > n) {
*info = -3;
} else if (lda < max(1,n)) {
*info = -5;
} else if (ldt < nb) {
*info = -8;
} else if (ldy < max(1,n)) {
*info = -10;
}
if (*info != 0) {
magma_xerbla( __func__, -(*info) );
return *info;
}
// adjust from 1-based indexing
k -= 1;
// Function Body
if (n <= 1)
return *info;
magma_device_t orig_dev;
magma_getdevice( &orig_dev );
magma_queue_t orig_stream;
magmablasGetKernelStream( &orig_stream );
// zero out current top block of V on all GPUs
for( d = 0; d < ngpu; ++d ) {
magma_setdevice( d );
magmablasSetKernelStream( data->streams[d] );
magmablas_claset( MagmaFull, nb, nb, c_zero, c_zero, dV(d,k,0), ldv );
}
// set all Y=0
lapackf77_claset( "Full", &n, &nb, &c_zero, &c_zero, Y, &ldy );
for (i = 0; i < nb; ++i) {
n_k_i_1 = n - k - i - 1;
n_k = n - k;
if (i > 0) {
// Finish applying I - V * T * V' on right
tmp = MAGMA_C_NEGATE( tau[i-1] );
blasf77_caxpy( &n_k, &tmp, Y(k,i-1), &ione, A(k,i), &ione );
// Apply I - V * T' * V' to this column (call it b) from the
// left, using the last column of T as workspace, w.
//
// Let V = ( V1 ) and b = ( b1 ) (first i-1 rows)
// ( V2 ) ( b2 )
// where V1 is unit lower triangular
// w := b1 = A(k+1:k+i, i)
blasf77_ccopy( &i,
A(k+1,i), &ione,
T(0,nb-1), &ione );
// w := V1' * b1 = VA(k+1:k+i, 0:i-1)' * w
blasf77_ctrmv( "Lower", "Conj", "Unit", &i,
A(k+1,0), &lda,
T(0,nb-1), &ione );
// w := w + V2'*b2 = w + VA(k+i+1:n-1, 0:i-1)' * A(k+i+1:n-1, i)
blasf77_cgemv( "Conj", &n_k_i_1, &i,
&c_one, A(k+i+1,0), &lda,
A(k+i+1,i), &ione,
&c_one, T(0,nb-1), &ione );
// w := T'*w = T(0:i-1, 0:i-1)' * w
blasf77_ctrmv( "Upper", "Conj", "Non-unit", &i,
T(0,0), &ldt,
T(0,nb-1), &ione );
// b2 := b2 - V2*w = A(k+i+1:n-1, i) - VA(k+i+1:n-1, 0:i-1) * w
blasf77_cgemv( "No trans", &n_k_i_1, &i,
&c_neg_one, A(k+i+1,0), &lda,
T(0,nb-1), &ione,
&c_one, A(k+i+1,i), &ione );
// w := V1*w = VA(k+1:k+i, 0:i-1) * w
blasf77_ctrmv( "Lower", "No trans", "Unit", &i,
A(k+1,0), &lda,
T(0,nb-1), &ione );
// b1 := b1 - w = A(k+1:k+i-1, i) - w
blasf77_caxpy( &i,
&c_neg_one, T(0,nb-1), &ione,
A(k+1,i), &ione );
// Restore diagonal element, saved below during previous iteration
*A(k+i,i-1) = ei;
}
// Generate the elementary reflector H(i) to annihilate A(k+i+1:n-1,i)
lapackf77_clarfg( &n_k_i_1,
A(k+i+1,i),
A(k+i+2,i), &ione, &tau[i] );
// Save diagonal element and set to one, to simplify multiplying by V
ei = *A(k+i+1,i);
*A(k+i+1,i) = c_one;
// compute yi = A vi = sum_g A{d} vi{d}
nblocks = (n-1) / nb / ngpu + 1;
for( d = 0; d < ngpu; ++d ) {
magma_setdevice( d );
magmablasSetKernelStream( data->streams[d] );
// dV(k+i+1:n-1, i) = VA(k+i:n, i)
magma_csetvector_async( n_k_i_1,
A(k+i+1,i), 1,
dV(d, k+i+1, i), 1, data->streams[d] );
// copy column of dV -> dVd, using block cyclic distribution.
// This assumes V and Vd have been padded so that
// a 2D matrix copy doesn't access them out-of-bounds
gblock = k / nb;
lblock = gblock / ngpu;
lgid = gblock % ngpu;
if ( d < lgid ) {
lblock += 1;
}
// treat V as (nb*ngpu) x nblock matrix, and Vd as nb x nblock matrix
magmablas_clacpy( MagmaFull, nb, nblocks-lblock,
dV (d, d*nb + lblock*nb*ngpu, i), nb*ngpu,
dVd(d, 0 + lblock*nb, i), nb );
// convert global indices (k) to local indices (dk)
magma_indices_1D_bcyclic( nb, ngpu, d, k+i+1, n, &dki1, &dn );
// dY(k:n, i) = dA(k:n, k+i+1:n) * dV(k+i+1:n, i)
// skip if matrix is empty
// each GPU copies to different temporary vector in Y,
// which are summed in separate loop below
if ( dn-dki1 > 0 ) {
magma_cgemv( MagmaNoTrans, n-k, dn-dki1,
c_one, dA (d, k, dki1), ldda,
dVd(d, dki1, i), 1,
c_zero, dY (d, k, i), 1 );
// copy vector to host, storing in column nb+d of Y
// as temporary space (Y has >= nb+ngpu columns)
magma_cgetvector_async( n-k,
dY(d, k, i), 1,
Y(k, nb+d), 1, data->streams[d] );
}
}
// while GPU is doing above Ag*v...
// Compute T(0:i,i) = [ -tau T V' vi ]
// [ tau ]
// T(0:i-1, i) = -tau VA(k+i+1:n-1, 0:i-1)' VA(k+i+1:n-1, i)
scale = MAGMA_C_NEGATE( tau[i] );
blasf77_cgemv( "Conj", &n_k_i_1, &i,
&scale, A(k+i+1,0), &lda,
A(k+i+1,i), &ione,
&c_zero, T(0,i), &ione );
// T(0:i-1, i) = T(0:i-1, 0:i-1) * T(0:i-1, i)
blasf77_ctrmv( "Upper", "No trans", "Non-unit", &i,
T(0,0), &ldt,
T(0,i), &ione );
*T(i,i) = tau[i];
// apply reflectors to next column, A(i+1), on right only.
// one axpy will be required to finish this, in the next iteration above
if ( i > 0 && i+1 < nb ) {
// Update next column, A(k:n,i+1), applying Q on right.
// One axpy will be required to finish this, in the next iteration
// above, after yi is computed.
// This updates one more row than LAPACK does (row k),
// making block above panel an even multiple of nb.
// Use last column of T as workspace, w.
magma_int_t i1 = i+1;
// If complex, conjugate row of V, and undo afterwards
#if defined(PRECISION_z) || defined(PRECISION_c)
lapackf77_clacgv( &i1, A(k+i1,0), &lda );
#endif
// w = T(0:i, 0:i+1) * VA(k+i+1, 0:i+1)'
// T is now rectangular, so we use gemv instead of trmv as in lapack.
blasf77_cgemv( "No trans", &i, &i1,
&c_one, T(0,0), &ldt,
A(k+i1,0), &lda,
&c_zero, T(0,nb-1), &ione );
#if defined(PRECISION_z) || defined(PRECISION_c)
lapackf77_clacgv( &i1, A(k+i1,0), &lda );
#endif
// A(k:n, i+1) -= Y(k:n, 0:i) * w
blasf77_cgemv( "No trans", &n_k, &i,
&c_neg_one, Y(k,0), &ldy,
T(0,nb-1), &ione,
&c_one, A(k,i1), &ione );
}
// yi = sum_g yi{d}
for( d = 0; d < ngpu; ++d ) {
magma_setdevice( d );
magma_queue_sync( data->streams[d] );
magma_indices_1D_bcyclic( nb, ngpu, d, k+i+1, n, &dki1, &dn );
if ( dn-dki1 > 0 ) {
// yi = yi + yi{d}
blasf77_caxpy( &n_k, &c_one, Y(k,nb+d), &ione, Y(k,i), &ione );
}
}
}
// Restore diagonal element
*A(k+nb,nb-1) = ei;
// compute Y = Am V = sum_g Am{d} V{d} --- top part, Y(0:k-1,:)
for( d = 0; d < ngpu; ++d ) {
magma_setdevice( d );
magmablasSetKernelStream( data->streams[d] );
// convert global indices (k) to local indices (dk)
magma_indices_1D_bcyclic( nb, ngpu, d, k+1, n, &dki1, &dn );
// dY(0:k, :) = dA(0:k, k+i+1:n-1) * dV(k+i+1:n-1, :)
// skip if matrix is empty
// each GPU copies to different temporary block in Y,
// which are summed in separate loop below
if ( dn-dki1 > 0 ) {
magma_cgemm( MagmaNoTrans, MagmaNoTrans, k, nb, dn-dki1,
c_one, dA (d, 0, dki1), ldda,
dVd(d, dki1, 0), ldvd,
c_zero, dY (d, 0, 0), ldda );
// copy result to host, storing in columns [nb + nb*d : nb + nb*(d+1)] of Y
// as temporary space (Y has nb + nb*ngpu columns)
magma_cgetmatrix_async( k, nb,
dY(d, 0, 0), ldda,
Y(0,nb+nb*d), ldy, data->streams[d] );
}
}
// Y = sum_g Y{d}
for( d = 0; d < ngpu; ++d ) {
magma_setdevice( d );
magma_queue_sync( 0 );
magma_indices_1D_bcyclic( nb, ngpu, d, k+1, n, &dki1, &dn );
if ( dn-dki1 > 0 ) {
// Y = Y + Am V
for( i = 0; i < nb; ++i ) {
blasf77_caxpy( &k, &c_one, Y(0,nb+nb*d+i), &ione, Y(0,i), &ione );
}
}
}
// copy Y and T matrices to GPUs
for( d = 0; d < ngpu; ++d ) {
magma_setdevice( d );
magma_csetmatrix_async( n, nb, Y, ldy, dY(d, 0, 0), ldda, data->streams[d] );
magma_csetmatrix_async( nb, nb, T, nb, dTi(d), nb, data->streams[d] );
}
magma_setdevice( orig_dev );
magmablasSetKernelStream( orig_stream );
return *info;
} /* magma_clahr2 */
extern "C" magma_int_t
magma_clahr2(
magma_int_t n, magma_int_t k, magma_int_t nb,
magmaFloatComplex *dA, magmaFloatComplex *dV,
magmaFloatComplex *A, magma_int_t lda,
magmaFloatComplex *tau,
magmaFloatComplex *T, magma_int_t ldt,
magmaFloatComplex *Y, magma_int_t ldy )
{
/* -- MAGMA (version 1.4.1) --
Univ. of Tennessee, Knoxville
Univ. of California, Berkeley
Univ. of Colorado, Denver
December 2013
Purpose
=======
CLAHR2 reduces the first NB columns of a complex general n-BY-(n-k+1)
matrix A so that elements below the k-th subdiagonal are zero. The
reduction is performed by an orthogonal similarity transformation
Q' * A * Q. The routine returns the matrices V and T which determine
Q as a block reflector I - V*T*V', and also the matrix Y = A * V.
(Note this is different than LAPACK, which computes Y = A * V * T.)
This is an auxiliary routine called by CGEHRD.
Arguments
=========
N (input) INTEGER
The order of the matrix A.
K (input) INTEGER
The offset for the reduction. Elements below the k-th
subdiagonal in the first NB columns are reduced to zero.
K < N.
NB (input) INTEGER
The number of columns to be reduced.
dA (input/output) COMPLEX array on the GPU, dimension (LDA,N-K+1)
On entry, the n-by-(n-k+1) general matrix A.
On exit, the elements in rows K:N of the first NB columns are
overwritten with the matrix Y.
DV (output) COMPLEX array on the GPU, dimension (N, NB)
On exit this contains the Householder vectors of the transformation.
A (input/output) COMPLEX array, dimension (LDA,N-K+1)
On entry, the n-by-(n-k+1) general matrix A.
On exit, the elements on and above the k-th subdiagonal in
the first NB columns are overwritten with the corresponding
elements of the reduced matrix; the elements below the k-th
subdiagonal, with the array TAU, represent the matrix Q as a
product of elementary reflectors. The other columns of A are
unchanged. See Further Details.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,N).
TAU (output) COMPLEX array, dimension (NB)
The scalar factors of the elementary reflectors. See Further
Details.
T (output) COMPLEX array, dimension (LDT,NB)
The upper triangular matrix T.
LDT (input) INTEGER
The leading dimension of the array T. LDT >= NB.
Y (output) COMPLEX array, dimension (LDY,NB)
The n-by-nb matrix Y.
LDY (input) INTEGER
The leading dimension of the array Y. LDY >= N.
Further Details
===============
The matrix Q is represented as a product of nb elementary reflectors
Q = H(1) H(2) . . . H(nb).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a complex scalar, and v is a complex vector with
v(1:i+k-1) = 0, v(i+k) = 1; v(i+k+1:n) is stored on exit in
A(i+k+1:n,i), and tau in TAU(i).
The elements of the vectors v together form the (n-k+1)-by-nb matrix
V which is needed, with T and Y, to apply the transformation to the
unreduced part of the matrix, using an update of the form:
A := (I - V*T*V') * (A - Y*T*V').
The contents of A on exit are illustrated by the following example
with n = 7, k = 3 and nb = 2:
( a a a a a )
( a a a a a )
( a a a a a )
( h h a a a )
( v1 h a a a )
( v1 v2 a a a )
( v1 v2 a a a )
where "a" denotes an element of the original matrix A, h denotes a
modified element of the upper Hessenberg matrix H, and vi denotes an
element of the vector defining H(i).
This implementation follows the hybrid algorithm and notations described in
S. Tomov and J. Dongarra, "Accelerating the reduction to upper Hessenberg
form through hybrid GPU-based computing," University of Tennessee Computer
Science Technical Report, UT-CS-09-642 (also LAPACK Working Note 219),
May 24, 2009.
===================================================================== */
#define A( i, j ) ( A + (i) + (j)*lda)
#define Y( i, j ) ( Y + (i) + (j)*ldy)
#define T( i, j ) ( T + (i) + (j)*ldt)
#define dA( i, j ) (dA + (i) + (j)*ldda)
#define dV( i, j ) (dV + (i) + (j)*ldda)
magmaFloatComplex c_zero = MAGMA_C_ZERO;
magmaFloatComplex c_one = MAGMA_C_ONE;
magmaFloatComplex c_neg_one = MAGMA_C_NEG_ONE;
magma_int_t ldda = lda;
magma_int_t ione = 1;
magma_int_t n_k_i_1, n_k;
magmaFloatComplex scale;
magma_int_t i;
magmaFloatComplex ei = MAGMA_C_ZERO;
// adjust from 1-based indexing
k -= 1;
// Function Body
if (n <= 1)
return 0;
for (i = 0; i < nb; ++i) {
n_k_i_1 = n - k - i - 1;
n_k = n - k;
if (i > 0) {
// Update A(k:n-1,i); Update i-th column of A - Y * T * V'
// This updates one more row than LAPACK does (row k),
// making the block above the panel an even multiple of nb.
// Use last column of T as workspace, w.
// w(0:i-1, nb-1) = VA(k+i, 0:i-1)'
blasf77_ccopy( &i,
A(k+i,0), &lda,
T(0,nb-1), &ione );
#if defined(PRECISION_z) || defined(PRECISION_c)
// If complex, conjugate row of V.
lapackf77_clacgv(&i, T(0,nb-1), &ione);
#endif
// w = T(0:i-1, 0:i-1) * w
blasf77_ctrmv( "Upper", "No trans", "No trans", &i,
T(0,0), &ldt,
T(0,nb-1), &ione );
// A(k:n-1, i) -= Y(k:n-1, 0:i-1) * w
blasf77_cgemv( "No trans", &n_k, &i,
&c_neg_one, Y(k,0), &ldy,
T(0,nb-1), &ione,
&c_one, A(k,i), &ione );
// Apply I - V * T' * V' to this column (call it b) from the
// left, using the last column of T as workspace, w.
//
// Let V = ( V1 ) and b = ( b1 ) (first i-1 rows)
// ( V2 ) ( b2 )
// where V1 is unit lower triangular
// w := b1 = A(k+1:k+i, i)
blasf77_ccopy( &i,
A(k+1,i), &ione,
T(0,nb-1), &ione );
// w := V1' * b1 = VA(k+1:k+i, 0:i-1)' * w
blasf77_ctrmv( "Lower", "Conj", "Unit", &i,
A(k+1,0), &lda,
T(0,nb-1), &ione );
// w := w + V2'*b2 = w + VA(k+i+1:n-1, 0:i-1)' * A(k+i+1:n-1, i)
blasf77_cgemv( "Conj", &n_k_i_1, &i,
&c_one, A(k+i+1,0), &lda,
A(k+i+1,i), &ione,
&c_one, T(0,nb-1), &ione );
// w := T'*w = T(0:i-1, 0:i-1)' * w
blasf77_ctrmv( "Upper", "Conj", "Non-unit", &i,
T(0,0), &ldt,
T(0,nb-1), &ione );
// b2 := b2 - V2*w = A(k+i+1:n-1, i) - VA(k+i+1:n-1, 0:i-1) * w
blasf77_cgemv( "No trans", &n_k_i_1, &i,
&c_neg_one, A(k+i+1,0), &lda,
T(0,nb-1), &ione,
&c_one, A(k+i+1,i), &ione );
// w := V1*w = VA(k+1:k+i, 0:i-1) * w
blasf77_ctrmv( "Lower", "No trans", "Unit", &i,
A(k+1,0), &lda,
T(0,nb-1), &ione );
// b1 := b1 - w = A(k+1:k+i-1, i) - w
blasf77_caxpy( &i,
&c_neg_one, T(0,nb-1), &ione,
A(k+1,i), &ione );
// Restore diagonal element, saved below during previous iteration
*A(k+i,i-1) = ei;
}
// Generate the elementary reflector H(i) to annihilate A(k+i+1:n-1,i)
lapackf77_clarfg( &n_k_i_1,
A(k+i+1,i),
A(k+i+2,i), &ione, &tau[i] );
// Save diagonal element and set to one, to simplify multiplying by V
ei = *A(k+i+1,i);
*A(k+i+1,i) = c_one;
// dV(i+1:n-k-1, i) = VA(k+i+1:n-1, i)
magma_csetvector( n_k_i_1,
A(k+i+1,i), 1,
dV(i+1,i), 1 );
// Compute Y(k+1:n,i) = A vi
// dA(k:n-1, i) = dA(k:n-1, i+1:n-k-1) * dV(i+1:n-k-1, i)
magma_cgemv( MagmaNoTrans, n_k, n_k_i_1,
c_one, dA(k,i+1), ldda,
dV(i+1,i), ione,
c_zero, dA(k,i), ione );
// Compute T(0:i,i) = [ -tau T V' vi ]
// [ tau ]
// T(0:i-1, i) = -tau VA(k+i+1:n-1, 0:i-1)' VA(k+i+1:n-1, i)
scale = MAGMA_C_NEGATE( tau[i]);
blasf77_cgemv( "Conj", &n_k_i_1, &i,
&scale, A(k+i+1,0), &lda,
A(k+i+1,i), &ione,
&c_zero, T(0,i), &ione );
// T(0:i-1, i) = T(0:i-1, 0:i-1) * T(0:i-1, i)
blasf77_ctrmv( "Upper", "No trans", "Non-unit", &i,
T(0,0), &ldt,
T(0,i), &ione );
*T(i,i) = tau[i];
// Y(k:n-1, i) = dA(k:n-1, i)
magma_cgetvector( n-k,
dA(k,i), 1,
Y(k,i), 1 );
}
// Restore diagonal element
*A(k+nb,nb-1) = ei;
return 0;
} // magma_clahr2
