gcc/

	PR tree-optimization/55018
	* basic-block.h (dfs_find_deadend): New prototype.
	* cfganal.c (dfs_find_deadend): No longer static.  Use bitmap
	instead of sbitmap for visited.
	(flow_dfs_compute_reverse_execute): Use dfs_find_deadend here, too.
	* dominance.c (calc_dfs_tree): If saw_unconnected,
	traverse from dfs_find_deadend of unconnected b
	instead of b directly.

testsuite/
	PR tree-optimization/55018
	* gcc.dg/torture/pr55018.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@193047 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 02e0d4e..9bad56c 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2012-10-31  Steven Bosscher  <steven@gcc.gnu.org>
+           Jakub Jelinek  <jakub@redhat.com>
+
+       PR tree-optimization/55018
+       * basic-block.h (dfs_find_deadend): New prototype.
+       * cfganal.c (dfs_find_deadend): No longer static.  Use bitmap
+       instead of sbitmap for visited.
+       (flow_dfs_compute_reverse_execute): Use dfs_find_deadend here, too.
+       * dominance.c (calc_dfs_tree): If saw_unconnected,
+       traverse from dfs_find_deadend of unconnected b
+       instead of b directly.
+
 2012-10-31  Eric Botcazou  <ebotcazou@adacore.com>
 
        * config/i386/i386.c (ix86_expand_prologue): Emit frame info for the

diff --git a/gcc/basic-block.h b/gcc/basic-block.h
index d9bd3b7..b28c443 100644 (file)
--- a/gcc/basic-block.h
+++ b/gcc/basic-block.h
@@ -787,6 +787,7 @@ extern void remove_fake_exit_edges (void);
 extern void add_noreturn_fake_exit_edges (void);
 extern void connect_infinite_loops_to_exit (void);
 extern int post_order_compute (int *, bool, bool);
+extern basic_block dfs_find_deadend (basic_block);
 extern int inverted_post_order_compute (int *);
 extern int pre_and_rev_post_order_compute (int *, int *, bool);
 extern int dfs_enumerate_from (basic_block, int,

diff --git a/gcc/cfganal.c b/gcc/cfganal.c
index 58c763f..4bef629 100644 (file)
--- a/gcc/cfganal.c
+++ b/gcc/cfganal.c
@@ -573,7 +573,9 @@ post_order_compute (int *post_order, bool include_entry_exit,
 }
 
 
-/* Helper routine for inverted_post_order_compute.
+/* Helper routine for inverted_post_order_compute
+   flow_dfs_compute_reverse_execute, and the reverse-CFG
+   deapth first search in dominance.c.
    BB has to belong to a region of CFG
    unreachable by inverted traversal from the exit.
    i.e. there's no control flow path from ENTRY to EXIT
@@ -593,19 +595,17 @@ post_order_compute (int *post_order, bool include_entry_exit,
    that all blocks in the region are reachable
    by starting an inverted traversal from the returned block.  */
 
-static basic_block
+basic_block
 dfs_find_deadend (basic_block bb)
 {
-  sbitmap visited = sbitmap_alloc (last_basic_block);
-  bitmap_clear (visited);
+  bitmap visited = BITMAP_ALLOC (NULL);
 
   for (;;)
     {
-      SET_BIT (visited, bb->index);
       if (EDGE_COUNT (bb->succs) == 0
-          || TEST_BIT (visited, EDGE_SUCC (bb, 0)->dest->index))
+         || ! bitmap_set_bit (visited, bb->index))
         {
-          sbitmap_free (visited);
+          BITMAP_FREE (visited);
           return bb;
         }
 
@@ -958,7 +958,7 @@ flow_dfs_compute_reverse_execute (depth_first_search_ds data,
   /* Determine if there are unvisited basic blocks.  */
   FOR_BB_BETWEEN (bb, last_unvisited, NULL, prev_bb)
     if (!TEST_BIT (data->visited_blocks, bb->index))
-      return bb;
+      return dfs_find_deadend (bb);
 
   return NULL;
 }

diff --git a/gcc/dominance.c b/gcc/dominance.c
index 10a58cd..683f3f5 100644 (file)
--- a/gcc/dominance.c
+++ b/gcc/dominance.c
@@ -377,14 +377,18 @@ calc_dfs_tree (struct dom_info *di, bool reverse)
        {
          FOR_EACH_BB_REVERSE (b)
            {
+             basic_block b2;
              if (di->dfs_order[b->index])
                continue;
-             bitmap_set_bit (di->fake_exit_edge, b->index);
-             di->dfs_order[b->index] = di->dfsnum;
-             di->dfs_to_bb[di->dfsnum] = b;
+             b2 = dfs_find_deadend (b);
+             gcc_checking_assert (di->dfs_order[b2->index] == 0);
+             bitmap_set_bit (di->fake_exit_edge, b2->index);
+             di->dfs_order[b2->index] = di->dfsnum;
+             di->dfs_to_bb[di->dfsnum] = b2;
              di->dfs_parent[di->dfsnum] = di->dfs_order[last_basic_block];
              di->dfsnum++;
-             calc_dfs_tree_nonrec (di, b, reverse);
+             calc_dfs_tree_nonrec (di, b2, reverse);
+             gcc_checking_assert (di->dfs_order[b->index]);
            }
        }
     }

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index b32d9f7..1dc498d 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2012-10-31  Steven Bosscher  <steven@gcc.gnu.org>
+           Jakub Jelinek  <jakub@redhat.com>
+
+       PR tree-optimization/55018
+       * gcc.dg/torture/pr55018.c: New test.
+
 2012-10-31  Paolo Carlini  <paolo.carlini@oracle.com>
 
        PR c++/54583

diff --git a/gcc/testsuite/gcc.dg/torture/pr55018.c b/gcc/testsuite/gcc.dg/torture/pr55018.c
new file mode 100644 (file)
index 0000000..f9f34bc
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr55018.c
@@ -0,0 +1,22 @@
+/* PR tree-optimization/55018 */
+/* { dg-do compile } */
+/* { dg-options "-fdump-tree-optimized" } */
+
+void
+foo (int x)
+{
+  unsigned int a = 0;
+  int b = 3;
+  if (x)
+    b = 0;
+lab:
+  if (x)
+    goto lab;
+  a++;
+  if (b != 2)
+    __builtin_printf ("%u", a);
+  goto lab;
+}
+
+/* { dg-final { scan-tree-dump "printf" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */