NAME

SYNOPSIS

void HPL_logsort( const int NPROCS, const int ICURROC, int * IPLEN, int * IPMAP, int * IPMAPM1 );

DESCRIPTION

ARGUMENTS

NPROCS (global input) const int

On entry, NPROCS specifies the number of process rows in the process grid. NPROCS is at least one.

ICURROC (global input) const int

On entry, ICURROC is the source process row.

IPLEN (global input/output) int *

On entry, IPLEN is an array of dimension NPROCS+1, such that IPLEN[0] is 0, and IPLEN[i] contains the number of rows of U, that process i-1 has. On exit, IPLEN[i] is the number of rows of U in the processes before process IPMAP[i] after the sort, with the convention that IPLEN[NPROCS] is the total number of rows of the panel. In other words, IPLEN[i+1] - IPLEN[i] is the number of rows of A that should be moved to the process IPMAP[i]. IPLEN is such that the number of rows of the source process row is IPLEN[1] - IPLEN[0], and the remaining entries of this array are sorted so that the quantities IPLEN[i+1]-IPLEN[i] are logarithmically sorted.

IPMAP (global output) int *

On entry, IPMAP is an array of dimension NPROCS. On exit, array contains the logarithmic mapping of the processes. In other words, IPMAP[myroc] is the corresponding sorted process coordinate.

IPMAPM1 (global output) int *

On entry, IPMAPM1 is an array of dimension NPROCS. On exit, this array contains the inverse of the logarithmic mapping contained in IPMAP: IPMAPM1[ IPMAP[i] ] = i, for all i in [0.. NPROCS)

SEE ALSO