re PR tree-optimization/54494 (Missing store to volatile)

2012-09-06  Andrew Pinski  <apinski@cavium.com>

        PR tree-opt/54494
        * tree-inline.c (remap_gimple_op_r): Copy TREE_SIDE_EFFECTS also.
2012-09-06  Andrew Pinski  <apinski@cavium.com>

        PR tree-opt/54494
        * gcc.dg/tree-ssa/strlen-1.c: New testcase.

From-SVN: r191014

gcc/ChangeLog

+2012-09-06  Andrew Pinski  <apinski@cavium.com>
+
+	PR tree-opt/54494
+	* tree-inline.c (remap_gimple_op_r): Copy TREE_SIDE_EFFECTS also.
+
 2012-09-06  Jakub Jelinek  <jakub@redhat.com>
 
 	PR rtl-optimization/54455

gcc/testsuite/ChangeLog

+2012-09-06  Andrew Pinski  <apinski@cavium.com>
+
+	PR tree-opt/54494
+	* gcc.dg/tree-ssa/strlen-1.c: New testcase.
+
 2012-09-06  Jakub Jelinek  <jakub@redhat.com>
 
 	PR rtl-optimization/54455

gcc/testsuite/gcc.dg/tree-ssa/strlen-1.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+extern const unsigned long base;
+static inline void wreg(unsigned char val, unsigned long addr) __attribute__((always_inline));
+static inline void wreg(unsigned char val, unsigned long addr)
+{
+   *((volatile unsigned char *) (__SIZE_TYPE__) (base + addr)) = val;
+}
+void wreg_twice(void)
+{
+   wreg(0, 42);
+   wreg(0, 42);
+}
+
+/* We should not remove the second null character store to (base+42) address. */
+/* { dg-final { scan-tree-dump-times " ={v} 0;" 2 "optimized" } }  */
+/* { dg-final { cleanup-tree-dump "optimized" } }  */

gcc/tree-inline.c

@@ -848,6 +848,7 @@ remap_gimple_op_r (tree *tp, int *walk_subtrees, void *data)
 			     ptr, TREE_OPERAND (*tp, 1));
 	  TREE_THIS_NOTRAP (*tp) = TREE_THIS_NOTRAP (old);
 	  TREE_THIS_VOLATILE (*tp) = TREE_THIS_VOLATILE (old);
+	  TREE_SIDE_EFFECTS (*tp) = TREE_SIDE_EFFECTS (old);
 	  TREE_NO_WARNING (*tp) = TREE_NO_WARNING (old);
 	  *walk_subtrees = 0;
 	  return NULL;