Chris@42: /*
Chris@42:  * Copyright (c) 2003, 2007-14 Matteo Frigo
Chris@42:  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
Chris@42:  *
Chris@42:  * This program is free software; you can redistribute it and/or modify
Chris@42:  * it under the terms of the GNU General Public License as published by
Chris@42:  * the Free Software Foundation; either version 2 of the License, or
Chris@42:  * (at your option) any later version.
Chris@42:  *
Chris@42:  * This program is distributed in the hope that it will be useful,
Chris@42:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
Chris@42:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
Chris@42:  * GNU General Public License for more details.
Chris@42:  *
Chris@42:  * You should have received a copy of the GNU General Public License
Chris@42:  * along with this program; if not, write to the Free Software
Chris@42:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
Chris@42:  *
Chris@42:  */
Chris@42: 
Chris@42: 
Chris@42: #include "ifftw.h"
Chris@42: 
Chris@42: INT X(tensor_max_index)(const tensor *sz)
Chris@42: {
Chris@42:      int i;
Chris@42:      INT ni = 0, no = 0;
Chris@42: 
Chris@42:      A(FINITE_RNK(sz->rnk));
Chris@42:      for (i = 0; i < sz->rnk; ++i) {
Chris@42:           const iodim *p = sz->dims + i;
Chris@42:           ni += (p->n - 1) * X(iabs)(p->is);
Chris@42:           no += (p->n - 1) * X(iabs)(p->os);
Chris@42:      }
Chris@42:      return X(imax)(ni, no);
Chris@42: }
Chris@42: 
Chris@42: #define tensor_min_xstride(sz, xs) {			\
Chris@42:      A(FINITE_RNK(sz->rnk));				\
Chris@42:      if (sz->rnk == 0) return 0;			\
Chris@42:      else {						\
Chris@42:           int i;					\
Chris@42:           INT s = X(iabs)(sz->dims[0].xs);		\
Chris@42:           for (i = 1; i < sz->rnk; ++i)			\
Chris@42:                s = X(imin)(s, X(iabs)(sz->dims[i].xs));	\
Chris@42:           return s;					\
Chris@42:      }							\
Chris@42: }
Chris@42: 
Chris@42: INT X(tensor_min_istride)(const tensor *sz) tensor_min_xstride(sz, is)
Chris@42: INT X(tensor_min_ostride)(const tensor *sz) tensor_min_xstride(sz, os)
Chris@42: 
Chris@42: INT X(tensor_min_stride)(const tensor *sz)
Chris@42: {
Chris@42:      return X(imin)(X(tensor_min_istride)(sz), X(tensor_min_ostride)(sz));
Chris@42: }
Chris@42: 
Chris@42: int X(tensor_inplace_strides)(const tensor *sz)
Chris@42: {
Chris@42:      int i;
Chris@42:      A(FINITE_RNK(sz->rnk));
Chris@42:      for (i = 0; i < sz->rnk; ++i) {
Chris@42:           const iodim *p = sz->dims + i;
Chris@42:           if (p->is != p->os)
Chris@42:                return 0;
Chris@42:      }
Chris@42:      return 1;
Chris@42: }
Chris@42: 
Chris@42: int X(tensor_inplace_strides2)(const tensor *a, const tensor *b)
Chris@42: {
Chris@42:      return X(tensor_inplace_strides(a)) && X(tensor_inplace_strides(b));
Chris@42: }
Chris@42: 
Chris@42: /* return true (1) iff *any* strides of sz decrease when we
Chris@42:    tensor_inplace_copy(sz, k). */
Chris@42: static int tensor_strides_decrease(const tensor *sz, inplace_kind k)
Chris@42: {
Chris@42:      if (FINITE_RNK(sz->rnk)) {
Chris@42:           int i;
Chris@42:           for (i = 0; i < sz->rnk; ++i)
Chris@42:                if ((sz->dims[i].os - sz->dims[i].is)
Chris@42:                    * (k == INPLACE_OS ? (INT)1 : (INT)-1) < 0)
Chris@42:                     return 1;
Chris@42:      }
Chris@42:      return 0;
Chris@42: }
Chris@42: 
Chris@42: /* Return true (1) iff *any* strides of sz decrease when we
Chris@42:    tensor_inplace_copy(k) *or* if *all* strides of sz are unchanged
Chris@42:    but *any* strides of vecsz decrease.  This is used in indirect.c
Chris@42:    to determine whether to use INPLACE_IS or INPLACE_OS.
Chris@42: 
Chris@42:    Note: X(tensor_strides_decrease)(sz, vecsz, INPLACE_IS)
Chris@42:          || X(tensor_strides_decrease)(sz, vecsz, INPLACE_OS)
Chris@42:          || X(tensor_inplace_strides2)(p->sz, p->vecsz)
Chris@42:    must always be true. */
Chris@42: int X(tensor_strides_decrease)(const tensor *sz, const tensor *vecsz,
Chris@42: 			       inplace_kind k)
Chris@42: {
Chris@42:      return(tensor_strides_decrease(sz, k)
Chris@42: 	    || (X(tensor_inplace_strides)(sz)
Chris@42: 		&& tensor_strides_decrease(vecsz, k)));
Chris@42: }