re PR middle-end/37828 ([graphite] ICE in expand_scalar_variables_expr, at…

re PR middle-end/37828 ([graphite] ICE in expand_scalar_variables_expr, at graphite.c:3421 with -floop-block)

2008-10-15  Sebastian Pop  <sebastian.pop@amd.com>
    	    Harsha Jagasia  <harsha.jagasia@amd.com>

	PR tree-optimization/37828
	* testsuite/gcc.dg/graphite/pr37828.c: New.
	* graphite.c (graphite_trans_loop_block): Do not loop block
	single nested loops.


Co-Authored-By: Harsha Jagasia <harsha.jagasia@amd.com>

From-SVN: r141142

gcc/ChangeLog

 2008-10-15  Sebastian Pop  <sebastian.pop@amd.com>
+    	    Harsha Jagasia  <harsha.jagasia@amd.com>
+
+	PR tree-optimization/37828
+	* graphite.c (graphite_trans_loop_block): Do not loop block
+	single nested loops.
+
+2008-10-15  Sebastian Pop  <sebastian.pop@amd.com>
 
 	PR tree-optimization/37686
 	* tree-loop-linear.c (linear_transform_loops): Build a

gcc/graphite.c

@@ -4767,13 +4767,19 @@ graphite_trans_loop_block (VEC (graphite_bb_p, heap) *bbs, int loops)
   /* TODO: - Calculate the stride size automatically.  */
   int stride_size = 64;
 
+  /* It makes no sense to block a single loop.  */
+  for (i = 0; VEC_iterate (graphite_bb_p, bbs, i, gb); i++)
+    if (gbb_nb_loops (gb) < 2)
+      return false;
+
   for (i = 0; VEC_iterate (graphite_bb_p, bbs, i, gb); i++)
     transform_done |= graphite_trans_bb_block (gb, stride_size, loops);
 
   return transform_done;
 }
 
-/* Loop block all basic blocks of SCOP.  */
+/* Loop block all basic blocks of SCOP.  Return false when the
+   transform is not performed.  */
 
 static bool
 graphite_trans_scop_block (scop_p scop)
@@ -4790,10 +4796,10 @@ graphite_trans_scop_block (scop_p scop)
   lambda_vector last_schedule = lambda_vector_new (max_schedule);
 
   if (VEC_length (graphite_bb_p, SCOP_BBS (scop)) == 0)
-    return transform_done;
+    return false;
 
   /* Get the data of the first bb.  */
-  gb = VEC_index (graphite_bb_p, SCOP_BBS (scop), 0); 
+  gb = VEC_index (graphite_bb_p, SCOP_BBS (scop), 0);
   last_nb_loops = gbb_nb_loops (gb);
   lambda_vector_copy (GBB_STATIC_SCHEDULE (gb), last_schedule,
                       last_nb_loops + 1);

gcc/testsuite/ChangeLog

 2008-10-15  Sebastian Pop  <sebastian.pop@amd.com>
+    	    Harsha Jagasia  <harsha.jagasia@amd.com>
+
+	PR tree-optimization/37828
+	* testsuite/gcc.dg/graphite/pr37828.c: New.
+
+2008-10-15  Sebastian Pop  <sebastian.pop@amd.com>
 
 	PR tree-optimization/37686
 	* testsuite/gcc.dg/tree-ssa/pr37686.c: New.

gcc/testsuite/gcc.dg/graphite/pr37828.c

+/* { dg-options "-O2 -floop-block" } */
+
+typedef struct foo
+{
+  struct foo **Node;
+} foo;
+
+static int sort_and_split (foo **Root, foo **Finite, long first)
+{
+  foo *cd;
+  long i;
+  for (i = 0; i < first; i++)
+    cd->Node[i] = Finite[first+i];
+
+  sort_and_split(Root, Finite, first);
+  return (0);
+}
+
+
+void Build_foo(foo **Root, foo **Finite, foo **Infinite)
+{
+  long low, high;
+  while (sort_and_split(Root, Finite, low) == 0);
+}
+