cannam@127: /*
cannam@127:  * Copyright (c) 2003, 2007-14 Matteo Frigo
cannam@127:  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
cannam@127:  *
cannam@127:  * This program is free software; you can redistribute it and/or modify
cannam@127:  * it under the terms of the GNU General Public License as published by
cannam@127:  * the Free Software Foundation; either version 2 of the License, or
cannam@127:  * (at your option) any later version.
cannam@127:  *
cannam@127:  * This program is distributed in the hope that it will be useful,
cannam@127:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
cannam@127:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
cannam@127:  * GNU General Public License for more details.
cannam@127:  *
cannam@127:  * You should have received a copy of the GNU General Public License
cannam@127:  * along with this program; if not, write to the Free Software
cannam@127:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
cannam@127:  *
cannam@127:  */
cannam@127: 
cannam@127: 
cannam@127: #include "ifftw.h"
cannam@127: 
cannam@127: INT X(tensor_max_index)(const tensor *sz)
cannam@127: {
cannam@127:      int i;
cannam@127:      INT ni = 0, no = 0;
cannam@127: 
cannam@127:      A(FINITE_RNK(sz->rnk));
cannam@127:      for (i = 0; i < sz->rnk; ++i) {
cannam@127:           const iodim *p = sz->dims + i;
cannam@127:           ni += (p->n - 1) * X(iabs)(p->is);
cannam@127:           no += (p->n - 1) * X(iabs)(p->os);
cannam@127:      }
cannam@127:      return X(imax)(ni, no);
cannam@127: }
cannam@127: 
cannam@127: #define tensor_min_xstride(sz, xs) {			\
cannam@127:      A(FINITE_RNK(sz->rnk));				\
cannam@127:      if (sz->rnk == 0) return 0;			\
cannam@127:      else {						\
cannam@127:           int i;					\
cannam@127:           INT s = X(iabs)(sz->dims[0].xs);		\
cannam@127:           for (i = 1; i < sz->rnk; ++i)			\
cannam@127:                s = X(imin)(s, X(iabs)(sz->dims[i].xs));	\
cannam@127:           return s;					\
cannam@127:      }							\
cannam@127: }
cannam@127: 
cannam@127: INT X(tensor_min_istride)(const tensor *sz) tensor_min_xstride(sz, is)
cannam@127: INT X(tensor_min_ostride)(const tensor *sz) tensor_min_xstride(sz, os)
cannam@127: 
cannam@127: INT X(tensor_min_stride)(const tensor *sz)
cannam@127: {
cannam@127:      return X(imin)(X(tensor_min_istride)(sz), X(tensor_min_ostride)(sz));
cannam@127: }
cannam@127: 
cannam@127: int X(tensor_inplace_strides)(const tensor *sz)
cannam@127: {
cannam@127:      int i;
cannam@127:      A(FINITE_RNK(sz->rnk));
cannam@127:      for (i = 0; i < sz->rnk; ++i) {
cannam@127:           const iodim *p = sz->dims + i;
cannam@127:           if (p->is != p->os)
cannam@127:                return 0;
cannam@127:      }
cannam@127:      return 1;
cannam@127: }
cannam@127: 
cannam@127: int X(tensor_inplace_strides2)(const tensor *a, const tensor *b)
cannam@127: {
cannam@127:      return X(tensor_inplace_strides(a)) && X(tensor_inplace_strides(b));
cannam@127: }
cannam@127: 
cannam@127: /* return true (1) iff *any* strides of sz decrease when we
cannam@127:    tensor_inplace_copy(sz, k). */
cannam@127: static int tensor_strides_decrease(const tensor *sz, inplace_kind k)
cannam@127: {
cannam@127:      if (FINITE_RNK(sz->rnk)) {
cannam@127:           int i;
cannam@127:           for (i = 0; i < sz->rnk; ++i)
cannam@127:                if ((sz->dims[i].os - sz->dims[i].is)
cannam@127:                    * (k == INPLACE_OS ? (INT)1 : (INT)-1) < 0)
cannam@127:                     return 1;
cannam@127:      }
cannam@127:      return 0;
cannam@127: }
cannam@127: 
cannam@127: /* Return true (1) iff *any* strides of sz decrease when we
cannam@127:    tensor_inplace_copy(k) *or* if *all* strides of sz are unchanged
cannam@127:    but *any* strides of vecsz decrease.  This is used in indirect.c
cannam@127:    to determine whether to use INPLACE_IS or INPLACE_OS.
cannam@127: 
cannam@127:    Note: X(tensor_strides_decrease)(sz, vecsz, INPLACE_IS)
cannam@127:          || X(tensor_strides_decrease)(sz, vecsz, INPLACE_OS)
cannam@127:          || X(tensor_inplace_strides2)(p->sz, p->vecsz)
cannam@127:    must always be true. */
cannam@127: int X(tensor_strides_decrease)(const tensor *sz, const tensor *vecsz,
cannam@127: 			       inplace_kind k)
cannam@127: {
cannam@127:      return(tensor_strides_decrease(sz, k)
cannam@127: 	    || (X(tensor_inplace_strides)(sz)
cannam@127: 		&& tensor_strides_decrease(vecsz, k)));
cannam@127: }