HPL_rollN man page
HPL_rollN — Roll U and forward the column panel.
void HPL_rollN( HPL_T_panel * PBCST, int * IFLAG, HPL_T_panel * PANEL, const int N, double * U, const int LDU, const int * IPLEN, const int * IPMAP, const int * IPMAPM1 );
HPL_rollN rolls the local arrays containing the local pieces of U, so that on exit to this function U is replicated in every process row. In addition, this function probe for the presence of the column panel and forwards it when available.
- PBCST (local input/output) HPL_T_panel *
On entry, PBCST points to the data structure containing the panel (to be broadcast) information.
- IFLAG (local input/output) int *
On entry, IFLAG indicates whether or not the broadcast has already been completed. If not, probing will occur, and the outcome will be contained in IFLAG on exit.
- PANEL (local input/output) HPL_T_panel *
On entry, PANEL points to the data structure containing the panel (to be rolled) information.
- N (local input) const int
On entry, N specifies the number of columns of U. N must be at least zero.
- U (local input/output) double *
On entry, U is an array of dimension (LDU,*) containing the local pieces of U in each process row.
- LDU (local input) const int
On entry, LDU specifies the local leading dimension of U. LDU should be at least MAX(1,IPLEN[NPROW]).
- IPLEN (global input) const int *
On entry, IPLEN is an array of dimension NPROW+1. This array is such that IPLEN[i+1] - IPLEN[i] is the number of rows of U in each process row.
- IPMAP (global input) const int *
On entry, IMAP is an array of dimension NPROW. This array contains the logarithmic mapping of the processes. In other words, IMAP[myrow] is the absolute coordinate of the sorted process.
- IPMAPM1 (global input) const int *
On entry, IMAPM1 is an array of dimension NPROW. This array contains the inverse of the logarithmic mapping contained in IMAP: For i in [0.. NPROW) IMAPM1[IMAP[i]] = i.