Fix pdr accesses order

2016-04-09  Tom de Vries  <tom@codesourcery.com>

	PR tree-optimization/68953
	* graphite-sese-to-poly.c (pdr_add_memory_accesses): Order accesses from
	first to last subscript.

	* gcc.dg/graphite/pr68953.c: New test.

From-SVN: r234851

gcc/ChangeLog

+2016-04-09  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/68953
+	* graphite-sese-to-poly.c (pdr_add_memory_accesses): Order accesses from
+	first to last subscript.
+
 2016-04-09  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/70586

gcc/graphite-sese-to-poly.c

@@ -672,7 +672,7 @@ pdr_add_memory_accesses (isl_map *acc, dr_info &dri)
 
       aff = extract_affine (scop, afn,
 			    isl_space_domain (isl_map_get_space (acc)));
-      acc = set_index (acc, i + 1, aff);
+      acc = set_index (acc, nb_subscripts - i , aff);
     }
 
   return isl_map_coalesce (acc);

gcc/testsuite/ChangeLog

+2016-04-09  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/68953
+	* gcc.dg/graphite/pr68953.c: New test.
+
 2016-04-09  Dominique d'Humieres  <dominiq@lps.ens.fr>
 
 	PR fortran/70592

gcc/testsuite/gcc.dg/graphite/pr68953.c

+/* { dg-do run } */
+/* { dg-options "-O1 -floop-nest-optimize" } */
+
+extern void abort (void);
+
+int yu[4][1] = { { 1 }, { 2 }, { 3 }, { 4 } };
+
+static void __attribute__((noinline,noclone))
+foo (void)
+{
+  int zh, ro;
+
+  for (zh = 0; zh < 2; ++zh)
+    for (ro = 0; ro < 3; ++ro)
+      yu[ro][0] = yu[zh + 1][0];
+}
+
+int
+main (void)
+{
+  foo ();
+
+  if (yu[0][0] != 2
+      || yu[1][0] != 2
+      || yu[2][0] != 2
+      || yu[3][0] != 4)
+    abort ();
+
+  return 0;
+}