Fix PR43083: Do not handle regions ending with multiple edges on the exit BB.

2010-02-22  Sebastian Pop  <sebastian.pop@amd.com>

	PR middle-end/43083
	* graphite-scop-detection.c (create_single_exit_edge): Move
	the call to find_single_exit_edge to....
	(create_sese_edges): ...here.  Don't handle multiple edges
	exiting the function.
	(build_graphite_scops): Don't handle multiple edges
	exiting the function.

	* gcc.dg/graphite/pr43083.c: New.

From-SVN: r156997

gcc/ChangeLog.graphite

 2010-02-22  Sebastian Pop  <sebastian.pop@amd.com>
 
+	PR middle-end/43083
+	* graphite-scop-detection.c (create_single_exit_edge): Move
+	the call to find_single_exit_edge to....
+	(create_sese_edges): ...here.  Don't handle multiple edges
+	exiting the function.
+	(build_graphite_scops): Don't handle multiple edges
+	exiting the function.
+
+	* gcc.dg/graphite/pr43083.c: New.
+
+2010-02-22  Sebastian Pop  <sebastian.pop@amd.com>
+
 	PR middle-end/43097
 	* sese.c (get_rename): Assert that old_name is an SSA_NAME.
 	(rename_variables_in_stmt): Continue when the use is not an SSA_NAME.

gcc/graphite-scop-detection.c

@@ -935,9 +935,6 @@ create_single_exit_edge (sd_region *region)
   edge forwarder = NULL;
   basic_block exit;
 
-  if (find_single_exit_edge (region))
-    return;
-
   /* We create a forwarder bb (5) for all edges leaving this region
      (3->5, 4->5).  All other edges leading to the same bb, are moved
      to a new bb (6).  If these edges where part of another region (2->5)
@@ -1031,7 +1028,10 @@ create_sese_edges (VEC (sd_region, heap) *regions)
   mark_exit_edges (regions);
 
   for (i = 0; VEC_iterate (sd_region, regions, i, s); i++)
-    create_single_exit_edge (s);
+    /* Don't handle multiple edges exiting the function.  */
+    if (!find_single_exit_edge (s)
+	&& s->exit != EXIT_BLOCK_PTR)
+      create_single_exit_edge (s);
 
   unmark_exit_edges (regions);
 
@@ -1057,7 +1057,12 @@ build_graphite_scops (VEC (sd_region, heap) *regions,
     {
       edge entry = find_single_entry_edge (s);
       edge exit = find_single_exit_edge (s);
-      scop_p scop = new_scop (new_sese (entry, exit));
+      scop_p scop;
+
+      if (!exit)
+	continue;
+
+      scop = new_scop (new_sese (entry, exit));
       VEC_safe_push (scop_p, heap, *scops, scop);
 
       /* Are there overlapping SCoPs?  */
@@ -1323,7 +1328,7 @@ build_scops (VEC (scop_p, heap) **scops)
 
   canonicalize_loop_closed_ssa_form ();
   build_scops_1 (single_succ (ENTRY_BLOCK_PTR), ENTRY_BLOCK_PTR->loop_father,
-			      &regions, loop);
+		 &regions, loop);
   create_sese_edges (regions);
   build_graphite_scops (regions, scops);
 

gcc/testsuite/gcc.dg/graphite/pr43083.c

+/* { dg-options "-O3 -fgraphite-identity" } */
+
+extern void baz(void);
+
+static inline int bar(void)
+{
+  int i;
+  for (i = 0; i < 10; i++) baz();
+}
+
+int foo(void)
+{
+  if (bar() != 0) return 0;
+}