Chris@10: /*
Chris@10:  * Copyright (c) 2003, 2007-11 Matteo Frigo
Chris@10:  * Copyright (c) 2003, 2007-11 Massachusetts Institute of Technology
Chris@10:  *
Chris@10:  * This program is free software; you can redistribute it and/or modify
Chris@10:  * it under the terms of the GNU General Public License as published by
Chris@10:  * the Free Software Foundation; either version 2 of the License, or
Chris@10:  * (at your option) any later version.
Chris@10:  *
Chris@10:  * This program is distributed in the hope that it will be useful,
Chris@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
Chris@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
Chris@10:  * GNU General Public License for more details.
Chris@10:  *
Chris@10:  * You should have received a copy of the GNU General Public License
Chris@10:  * along with this program; if not, write to the Free Software
Chris@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
Chris@10:  *
Chris@10:  */
Chris@10: 
Chris@10: #include "ifftw-mpi.h"
Chris@10: 
Chris@10: /* common functions for rearrangements of the data for the *-rank1-bigvec
Chris@10:    solvers */
Chris@10: 
Chris@10: static int div_mult(INT b, INT a) { 
Chris@10:      return (a > b && a % b == 0);
Chris@10: }
Chris@10: static int div_mult2(INT b, INT a, INT n) { 
Chris@10:      return (div_mult(b, a) && div_mult(n, b));
Chris@10: }
Chris@10: 
Chris@10: int XM(rearrange_applicable)(rearrangement rearrange, 
Chris@10: 			     ddim dim0, INT vn, int n_pes)
Chris@10: {
Chris@10:      /* note: it is important that cases other than CONTIG be
Chris@10: 	applicable only when the resulting transpose dimension
Chris@10: 	is divisible by n_pes; otherwise, the allocation size
Chris@10: 	returned by the API will be incorrect */
Chris@10:      return ((rearrange != DISCONTIG || div_mult(n_pes, vn))
Chris@10: 	     && (rearrange != SQUARE_BEFORE 
Chris@10: 		 || div_mult2(dim0.b[IB], vn, n_pes))
Chris@10: 	     && (rearrange != SQUARE_AFTER
Chris@10: 		 || (dim0.b[IB] != dim0.b[OB]
Chris@10: 		     && div_mult2(dim0.b[OB], vn, n_pes)))
Chris@10: 	     && (rearrange != SQUARE_MIDDLE
Chris@10: 		 || div_mult(dim0.n * n_pes, vn)));
Chris@10: }
Chris@10: 
Chris@10: INT XM(rearrange_ny)(rearrangement rearrange, ddim dim0, INT vn, int n_pes)
Chris@10: {
Chris@10:      switch (rearrange) {
Chris@10: 	 case CONTIG:
Chris@10: 	      return vn;
Chris@10: 	 case DISCONTIG:
Chris@10: 	      return n_pes;
Chris@10: 	 case SQUARE_BEFORE:
Chris@10: 	      return dim0.b[IB];
Chris@10: 	 case SQUARE_AFTER:
Chris@10: 	      return dim0.b[OB];
Chris@10: 	 case SQUARE_MIDDLE:
Chris@10: 	      return dim0.n * n_pes;
Chris@10:      }
Chris@10:      return 0;
Chris@10: }