cannam@95: /*
cannam@95:  * Copyright (c) 2003, 2007-11 Matteo Frigo
cannam@95:  * Copyright (c) 2003, 2007-11 Massachusetts Institute of Technology
cannam@95:  *
cannam@95:  * This program is free software; you can redistribute it and/or modify
cannam@95:  * it under the terms of the GNU General Public License as published by
cannam@95:  * the Free Software Foundation; either version 2 of the License, or
cannam@95:  * (at your option) any later version.
cannam@95:  *
cannam@95:  * This program is distributed in the hope that it will be useful,
cannam@95:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
cannam@95:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
cannam@95:  * GNU General Public License for more details.
cannam@95:  *
cannam@95:  * You should have received a copy of the GNU General Public License
cannam@95:  * along with this program; if not, write to the Free Software
cannam@95:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
cannam@95:  *
cannam@95:  */
cannam@95: 
cannam@95: #include "ifftw-mpi.h"
cannam@95: 
cannam@95: /* common functions for rearrangements of the data for the *-rank1-bigvec
cannam@95:    solvers */
cannam@95: 
cannam@95: static int div_mult(INT b, INT a) { 
cannam@95:      return (a > b && a % b == 0);
cannam@95: }
cannam@95: static int div_mult2(INT b, INT a, INT n) { 
cannam@95:      return (div_mult(b, a) && div_mult(n, b));
cannam@95: }
cannam@95: 
cannam@95: int XM(rearrange_applicable)(rearrangement rearrange, 
cannam@95: 			     ddim dim0, INT vn, int n_pes)
cannam@95: {
cannam@95:      /* note: it is important that cases other than CONTIG be
cannam@95: 	applicable only when the resulting transpose dimension
cannam@95: 	is divisible by n_pes; otherwise, the allocation size
cannam@95: 	returned by the API will be incorrect */
cannam@95:      return ((rearrange != DISCONTIG || div_mult(n_pes, vn))
cannam@95: 	     && (rearrange != SQUARE_BEFORE 
cannam@95: 		 || div_mult2(dim0.b[IB], vn, n_pes))
cannam@95: 	     && (rearrange != SQUARE_AFTER
cannam@95: 		 || (dim0.b[IB] != dim0.b[OB]
cannam@95: 		     && div_mult2(dim0.b[OB], vn, n_pes)))
cannam@95: 	     && (rearrange != SQUARE_MIDDLE
cannam@95: 		 || div_mult(dim0.n * n_pes, vn)));
cannam@95: }
cannam@95: 
cannam@95: INT XM(rearrange_ny)(rearrangement rearrange, ddim dim0, INT vn, int n_pes)
cannam@95: {
cannam@95:      switch (rearrange) {
cannam@95: 	 case CONTIG:
cannam@95: 	      return vn;
cannam@95: 	 case DISCONTIG:
cannam@95: 	      return n_pes;
cannam@95: 	 case SQUARE_BEFORE:
cannam@95: 	      return dim0.b[IB];
cannam@95: 	 case SQUARE_AFTER:
cannam@95: 	      return dim0.b[OB];
cannam@95: 	 case SQUARE_MIDDLE:
cannam@95: 	      return dim0.n * n_pes;
cannam@95:      }
cannam@95:      return 0;
cannam@95: }