re PR tree-optimization/69606 (wrong code at -Os and above on x86_64-linux-gnu)

2016-02-02  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/69606
	* tree-ssa-math-opts.c (bswap_replace): Clear flow sensitive
	info on the result before moving a stmt.

	* gcc.dg/torture/pr69606.c: New testcase.

From-SVN: r233069

gcc/ChangeLog

+2016-02-02  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/69606
+	* tree-ssa-math-opts.c (bswap_replace): Clear flow sensitive
+	info on the result before moving a stmt.
+
 2016-02-02  Yuri Rumyantsev  <ysrumyan@gmail.com>
 
 	PR middle-end/68542

gcc/testsuite/ChangeLog

+2016-02-02  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/69606
+	* gcc.dg/torture/pr69606.c: New testcase.
+
 2016-02-02  Yuri Rumyantsev  <ysrumyan@gmail.com>
 
 	PR middle-end/68542

gcc/testsuite/gcc.dg/torture/pr69606.c

+/* { dg-do run } */
+
+char a;
+unsigned short b;
+int c, d;
+unsigned char e;
+
+int
+main ()
+{
+  int f = 1, g = ~a;
+  if (b > f)
+    {
+      e = b; 
+      d = b | e; 
+      g = 0;
+    }
+  c = 1 % g;
+  return 0; 
+}

gcc/tree-ssa-math-opts.c

@@ -2622,6 +2622,8 @@ bswap_replace (gimple *cur_stmt, gimple *src_stmt, tree fndecl,
       /* Move cur_stmt just before  one of the load of the original
 	 to ensure it has the same VUSE.  See PR61517 for what could
 	 go wrong.  */
+      if (gimple_bb (cur_stmt) != gimple_bb (src_stmt))
+	reset_flow_sensitive_info (gimple_assign_lhs (cur_stmt));
       gsi_move_before (&gsi, &gsi_ins);
       gsi = gsi_for_stmt (cur_stmt);