/* ---------------------------------------------------------------------
*
* -- PBLAS auxiliary routine (version 2.0) --
* University of Tennessee, Knoxville, Oak Ridge National Laboratory,
* and University of California, Berkeley.
* April 1, 1998
*
* ---------------------------------------------------------------------
*/
/*
* Include files
*/
#include "../pblas.h"
#include "../PBpblas.h"
#include "../PBtools.h"
#include "../PBblacs.h"
#include "../PBblas.h"
#ifdef __STDC__
void PB_COutV( PBTYP_T * TYPE, char * ROWCOL, char * ZEROIT, int M,
int N, int * DESCA, int K, char * * YAPTR, int * DYA,
int * YAFREE, int * YASUM )
#else
void PB_COutV( TYPE, ROWCOL, ZEROIT, M, N, DESCA, K, YAPTR, DYA,
YAFREE, YASUM )
/*
* .. Scalar Arguments ..
*/
char * ROWCOL, * ZEROIT;
int * YAFREE, K, M, N, * YASUM;
PBTYP_T * TYPE;
/*
* .. Array Arguments ..
*/
int * DESCA, * DYA;
char * * YAPTR;
#endif
{
/*
* Purpose
* =======
*
* PB_COutV returns a pointer to an array that contains a one-dimensio-
* nal ouput zero subvector which is replicated over the rows or columns
* of a submatrix described by DESCA. On return, the subvector is speci-
* fied by a pointer to some data, a descriptor array describing its
* layout, a logical value indicating if this local piece of data has
* been dynamically allocated by this function, a logical value speci-
* fying if sum reduction should occur. This routine is specifically
* designed for traditional Level 2 and 3 PBLAS operations using an out-
* put only vector such as PxTRMV, or PxTRMM.
*
* Notes
* =====
*
* A description vector is associated with each 2D block-cyclicly dis-
* tributed matrix. This vector stores the information required to
* establish the mapping between a matrix entry and its corresponding
* process and memory location.
*
* In the following comments, the character _ should be read as
* "of the distributed matrix". Let A be a generic term for any 2D
* block cyclicly distributed matrix. Its description vector is DESC_A:
*
* NOTATION STORED IN EXPLANATION
* ---------------- --------------- ------------------------------------
* DTYPE_A (global) DESCA[ DTYPE_ ] The descriptor type.
* CTXT_A (global) DESCA[ CTXT_ ] The BLACS context handle, indicating
* the NPROW x NPCOL BLACS process grid
* A is distributed over. The context
* itself is global, but the handle
* (the integer value) may vary.
* M_A (global) DESCA[ M_ ] The number of rows in the distribu-
* ted matrix A, M_A >= 0.
* N_A (global) DESCA[ N_ ] The number of columns in the distri-
* buted matrix A, N_A >= 0.
* IMB_A (global) DESCA[ IMB_ ] The number of rows of the upper left
* block of the matrix A, IMB_A > 0.
* INB_A (global) DESCA[ INB_ ] The number of columns of the upper
* left block of the matrix A,
* INB_A > 0.
* MB_A (global) DESCA[ MB_ ] The blocking factor used to distri-
* bute the last M_A-IMB_A rows of A,
* MB_A > 0.
* NB_A (global) DESCA[ NB_ ] The blocking factor used to distri-
* bute the last N_A-INB_A columns of
* A, NB_A > 0.
* RSRC_A (global) DESCA[ RSRC_ ] The process row over which the first
* row of the matrix A is distributed,
* NPROW > RSRC_A >= 0.
* CSRC_A (global) DESCA[ CSRC_ ] The process column over which the
* first column of A is distributed.
* NPCOL > CSRC_A >= 0.
* LLD_A (local) DESCA[ LLD_ ] The leading dimension of the local
* array storing the local blocks of
* the distributed matrix A,
* IF( Lc( 1, N_A ) > 0 )
* LLD_A >= MAX( 1, Lr( 1, M_A ) )
* ELSE
* LLD_A >= 1.
*
* Let K be the number of rows of a matrix A starting at the global in-
* dex IA,i.e, A( IA:IA+K-1, : ). Lr( IA, K ) denotes the number of rows
* that the process of row coordinate MYROW ( 0 <= MYROW < NPROW ) would
* receive if these K rows were distributed over NPROW processes. If K
* is the number of columns of a matrix A starting at the global index
* JA, i.e, A( :, JA:JA+K-1, : ), Lc( JA, K ) denotes the number of co-
* lumns that the process MYCOL ( 0 <= MYCOL < NPCOL ) would receive if
* these K columns were distributed over NPCOL processes.
*
* The values of Lr() and Lc() may be determined via a call to the func-
* tion PB_Cnumroc:
* Lr( IA, K ) = PB_Cnumroc( K, IA, IMB_A, MB_A, MYROW, RSRC_A, NPROW )
* Lc( JA, K ) = PB_Cnumroc( K, JA, INB_A, NB_A, MYCOL, CSRC_A, NPCOL )
*
* Arguments
* =========
*
* TYPE (local input) pointer to a PBTYP_T structure
* On entry, TYPE is a pointer to a structure of type PBTYP_T,
* that contains type information (See pblas.h).
*
* ROWCOL (global input) pointer to CHAR
* On entry, ROWCOL specifies if this routine should return a
* row or column subvector replicated over the underlying subma-
* trix as follows:
* = 'R' or 'r': A row subvector is returned,
* = 'C' or 'c': A column subvector is returned.
*
* M (global input) INTEGER
* On entry, M specifies the number of rows of the underlying
* submatrix described by DESCA. M must be at least zero.
*
* N (global input) INTEGER
* On entry, N specifies the number of columns of the underlying
* submatrix described by DESCA. N must be at least zero.
*
* DESCA (global and local input) INTEGER array
* On entry, DESCA is an integer array of dimension DLEN_. This
* is the array descriptor for the matrix A.
*
* K (global input) INTEGER
* On entry, K specifies the length of the non-distributed di-
* mension of the subvector sub( Y ). K must be at least zero.
*
* YAPTR (local output) pointer to pointer to CHAR
* On exit, * YAPTR is an array containing the same data as the
* subvector sub( Y ) which is replicated over the rows or co-
* lumns of the underlying matrix as specified by ROWCOL and
* DESCA.
*
* DYA (global and local output) INTEGER array
* On exit, DYA is a descriptor array of dimension DLEN_ descri-
* bing the data layout of the data pointed to by * YAPTR.
*
* YAFREE (local output) INTEGER
* On exit, YAFREE specifies if it was possible to reuse the
* subvector sub( Y ), i.e., if some dynamic memory was alloca-
* ted for the data pointed to by * YAPTR or not. When YAFREE is
* zero, no dynamic memory was allocated. Otherwise, some dyna-
* mic memory was allocated by this function that one MUST re-
* lease as soon as possible.
*
* YASUM (global output) INTEGER
* On exit, YASUM specifies if a global sum reduction should be
* performed to obtain the correct sub( Y ). When YASUM is zero,
* no reduction is to be performed, otherwise reduction should
* occur.
*
* -- Written on April 1, 1998 by
* Antoine Petitet, University of Tennessee, Knoxville 37996, USA.
*
* ---------------------------------------------------------------------
*/
/*
* .. Local Scalars ..
*/
int Acol, Aimb, Ainb, Amb, Amp, Anb, Anq, Arow, Yld, ctxt,
izero=0, nprow, myrow, npcol, mycol;
char * zero;
/* ..
* .. Executable Statements ..
*
*/
/*
* Initialize the output parameters to a default value
*/
*YAFREE = 0;
*YASUM = 0;
*YAPTR = NULL;
/*
* Quick return if possible
*/
if( ( M <= 0 ) || ( N <= 0 ) || ( K <= 0 ) )
{
if( Mupcase( ROWCOL[0] ) == CROW )
{
PB_Cdescset( DYA, K, N, 1, DESCA[INB_], 1, DESCA[NB_], DESCA[RSRC_],
DESCA[CSRC_], DESCA[CTXT_], 1 );
}
else
{
PB_Cdescset( DYA, M, K, DESCA[IMB_], 1, DESCA[MB_], 1, DESCA[RSRC_],
DESCA[CSRC_], DESCA[CTXT_], DESCA[LLD_] );
}
return;
}
/*
* Retrieve process grid information
*/
Cblacs_gridinfo( ( ctxt = DESCA[CTXT_] ), &nprow, &npcol, &myrow, &mycol );
Arow = DESCA[RSRC_]; Acol = DESCA[CSRC_];
if( Mupcase( ROWCOL[0] ) == CROW )
{
/*
* Want a row vector
*/
Ainb = DESCA[INB_]; Anb = DESCA[NB_];
Anq = PB_Cnumroc( N, 0, Ainb, Anb, mycol, Acol, npcol );
Yld = MAX( 1, K );
if( ( Arow < 0 ) || ( nprow == 1 ) ||
( PB_Cspan( M, 0, DESCA[IMB_], DESCA[MB_], Arow, nprow ) ) )
{
/*
* A spans all process rows. Y should be reduced iff A is not replicated and
* there is more than just one process row in the process grid.
*/
*YASUM = ( ( Arow >= 0 ) && ( nprow > 1 ) );
/*
* Allocate the space for Y in the processes owning at least one column of A,
* and initialize it to zero if requested.
*/
if( Anq > 0 )
{
*YAPTR = PB_Cmalloc( K * Anq * TYPE->size );
*YAFREE = 1;
if( Mupcase( ZEROIT[0] ) == CINIT )
{
zero = TYPE->zero;
TYPE->Ftzpad( C2F_CHAR( ALL ), C2F_CHAR( NOCONJG ), &K, &Anq,
&izero, zero, zero, *YAPTR, &Yld );
}
}
/*
* Describe the newly created operand
*/
PB_Cdescset( DYA, K, N, K, Ainb, 1, Anb, -1, Acol, ctxt, Yld );
}
else
{
/*
* A spans only one process row. There is no need to reduce Y or even to
* allocate some space for it outside this process row.
*/
*YASUM = 0;
if( ( myrow == Arow ) && ( Anq > 0 ) )
{
*YAPTR = PB_Cmalloc( K * Anq * TYPE->size );
*YAFREE = 1;
if( Mupcase( ZEROIT[0] ) == CINIT )
{
zero = TYPE->zero;
TYPE->Ftzpad( C2F_CHAR( ALL ), C2F_CHAR( NOCONJG ), &K, &Anq,
&izero, zero, zero, *YAPTR, &Yld );
}
}
/*
* Describe the newly created operand
*/
PB_Cdescset( DYA, K, N, K, Ainb, 1, Anb, Arow, Acol, ctxt, Yld );
}
}
else
{
/*
* Want a column vector
*/
Aimb = DESCA[ IMB_ ]; Amb = DESCA[ MB_ ];
Amp = PB_Cnumroc( M, 0, Aimb, Amb, myrow, Arow, nprow );
Yld = MAX( 1, Amp );
if( ( Acol < 0 ) || ( npcol == 1 ) ||
( PB_Cspan( N, 0, DESCA[INB_], DESCA[NB_], Acol, npcol ) ) )
{
/*
* A spans all process columns. Y should be reduced iff A is not replicated and
* there is more than just one process column in the process grid.
*/
*YASUM = ( ( Acol >= 0 ) && ( npcol > 1 ) );
/*
* Allocate the space for Y in the processes owning at least one row of A, and
* initialize it to zero if requested.
*/
if( Amp > 0 )
{
*YAPTR = PB_Cmalloc( Amp * K * TYPE->size );
*YAFREE = 1;
if( Mupcase( ZEROIT[0] ) == CINIT )
{
zero = TYPE->zero;
TYPE->Ftzpad( C2F_CHAR( ALL ), C2F_CHAR( NOCONJG ), &Amp, &K,
&izero, zero, zero, *YAPTR, &Yld );
}
}
/*
* Describe the newly created operand
*/
PB_Cdescset( DYA, M, K, Aimb, K, Amb, 1, Arow, -1, ctxt, Yld );
}
else
{
/*
* A spans only one process column. There is no need to reduce Y or even to
* allocate some space for it outside this process column.
*/
*YASUM = 0;
if( ( mycol == Acol ) && ( Amp > 0 ) )
{
*YAPTR = PB_Cmalloc( Amp * K * TYPE->size );
*YAFREE = 1;
if( Mupcase( ZEROIT[0] ) == CINIT )
{
zero = TYPE->zero;
TYPE->Ftzpad( C2F_CHAR( ALL ), C2F_CHAR( NOCONJG ), &Amp, &K,
&izero, zero, zero, *YAPTR, &Yld );
}
}
/*
* Describe the newly created operand
*/
PB_Cdescset( DYA, M, K, Aimb, K, Amb, 1, Arow, Acol, ctxt, Yld );
}
}
/*
* End of PB_COutV
*/
}