2011-10-18 Richard Guenther <rguenther@suse.de>

	PR tree-optimization/50767
	* tree-ssa-pre.c (create_expression_by_pieces): Update the
	folded statement.

	* gcc.dg/torture/pr50767.c: New testcase.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@180134 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2968fb0..d026022 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2011-10-18  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/50767
+       * tree-ssa-pre.c (create_expression_by_pieces): Update the
+       folded statement.
+

 2011-10-18  Julian Brown  <julian@codesourcery.com>
 
        * config/arm/arm.c (arm_block_move_unaligned_straight)
 2011-10-18  Julian Brown  <julian@codesourcery.com>
 
        * config/arm/arm.c (arm_block_move_unaligned_straight)

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 3216bfc..411f63e 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2011-10-18  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/50767
+       * gcc.dg/torture/pr50767.c: New testcase.
+

 2011-10-18  Julian Brown  <julian@codesourcery.com>
 
        * lib/target-supports.exp (check_effective_target_arm_unaligned): New.
 2011-10-18  Julian Brown  <julian@codesourcery.com>
 
        * lib/target-supports.exp (check_effective_target_arm_unaligned): New.

diff --git a/gcc/testsuite/gcc.dg/torture/pr50767.c b/gcc/testsuite/gcc.dg/torture/pr50767.c
new file mode 100644 (file)
index 0000000..96ab72e
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr50767.c
@@ -0,0 +1,21 @@
+/* { dg-do compile } */
+/* { dg-options "-fno-tree-copy-prop -fno-tree-dominator-opts" } */
+
+struct S
+{
+  struct S *s;
+};
+
+static struct S *ss;
+struct S *s;
+
+void bar(void);
+
+void foo(void)
+{
+  for (;;)
+    {
+      s->s = ss;
+      bar ();
+    }
+}

diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c
index a7f6cee..60ae35c 100644 (file)
--- a/gcc/tree-ssa-pre.c
+++ b/gcc/tree-ssa-pre.c
@@ -3188,7 +3188,8 @@ create_expression_by_pieces (basic_block block, pre_expr expr,
 
   /* Fold the last statement.  */
   gsi = gsi_last (*stmts);
 
   /* Fold the last statement.  */
   gsi = gsi_last (*stmts);

-  fold_stmt_inplace (&gsi);
+  if (fold_stmt_inplace (&gsi))
+    update_stmt (gsi_stmt (gsi));

 
   /* Add a value number to the temporary.
      The value may already exist in either NEW_SETS, or AVAIL_OUT, because
 
   /* Add a value number to the temporary.
      The value may already exist in either NEW_SETS, or AVAIL_OUT, because