isl_multi_identity_templ.c

   1 /*
   2  * Copyright 2012      Ecole Normale Superieure
   3  *
   4  * Use of this software is governed by the MIT license
   5  *
   6  * Written by Sven Verdoolaege,
   7  * Ecole Normale Superieure, 45 rue d'Ulm, 75230 Paris, France
   8  */
   9
  10 #include <isl/space.h>
  11 #include <isl/local_space.h>
  12
  13 #include <isl_multi_macro.h>
  14
  15 /* Create a multi expression in the given space that maps each
  16  * input dimension to the corresponding output dimension.
  17  */
  18 __isl_give MULTI(BASE) *FN(MULTI(BASE),identity)(__isl_take isl_space *space)
  19 {
  20         int i, n;
  21         isl_local_space *ls;
  22         MULTI(BASE) *multi;
  23
  24         if (!space)
  25                 return NULL;
  26
  27         if (isl_space_is_set(space))
  28                 isl_die(isl_space_get_ctx(space), isl_error_invalid,
  29                         "expecting map space", goto error);
  30
  31         n = isl_space_dim(space, isl_dim_out);
  32         if (n != isl_space_dim(space, isl_dim_in))
  33                 isl_die(isl_space_get_ctx(space), isl_error_invalid,
  34                         "number of input and output dimensions needs to be "
  35                         "the same", goto error);
  36
  37         multi = FN(MULTI(BASE),alloc)(isl_space_copy(space));
  38
  39         if (!n) {
  40                 isl_space_free(space);
  41                 return multi;
  42         }
  43
  44         space = isl_space_domain(space);
  45         ls = isl_local_space_from_space(space);
  46
  47         for (i = 0; i < n; ++i) {
  48                 EL *el;
  49                 el = FN(EL,var_on_domain)(isl_local_space_copy(ls),
  50                                                 isl_dim_set, i);
  51                 multi = FN(FN(MULTI(BASE),set),BASE)(multi, i, el);
  52         }
  53
  54         isl_local_space_free(ls);
  55
  56         return multi;
  57 error:
  58         isl_space_free(space);
  59         return NULL;
  60 }