PR middle-end/27332

	* tree-loop-linear.c (try_interchange_loops): Test for
	no data dependences.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@113856 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index ca43a0e..4ecc27a 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2006-05-17  Sebastian Pop  <pop@cri.ensmp.fr>
+
+       PR middle-end/27332
+       * tree-loop-linear.c (try_interchange_loops): Test for 
+       no data dependences.
+

 2006-05-17  Zdenek Dvorak <dvorakz@suse.cz>
 
        PR tree-optimization/27548
 2006-05-17  Zdenek Dvorak <dvorakz@suse.cz>
 
        PR tree-optimization/27548

diff --git a/gcc/tree-loop-linear.c b/gcc/tree-loop-linear.c
index bf353e5..c648ef7 100644 (file)
--- a/gcc/tree-loop-linear.c
+++ b/gcc/tree-loop-linear.c
@@ -178,6 +178,9 @@ try_interchange_loops (lambda_trans_matrix trans,
   unsigned int nb_deps_not_carried_by_i, nb_deps_not_carried_by_j;
   struct data_dependence_relation *ddr;
 
   unsigned int nb_deps_not_carried_by_i, nb_deps_not_carried_by_j;
   struct data_dependence_relation *ddr;
 

+  if (VEC_length (ddr_p, dependence_relations) == 0)
+    return trans;
+

   /* When there is an unknown relation in the dependence_relations, we
      know that it is no worth looking at this loop nest: give up.  */
   ddr = VEC_index (ddr_p, dependence_relations, 0);
   /* When there is an unknown relation in the dependence_relations, we
      know that it is no worth looking at this loop nest: give up.  */
   ddr = VEC_index (ddr_p, dependence_relations, 0);