re PR tree-optimization/53501 (scev introduces signed overflow)

2012-05-30  Richard Guenther  <rguenther@suse.de>

	PR middle-end/53501
	* fold-const.c (fold_binary_loc): Make sure to call
	fold_plusminus_mult_expr with the original sign of operands.

	* gcc.dg/torture/pr53501.c: New testcase.
	* c-c++-common/restrict-2.c: Adjust.

From-SVN: r188009

5 files changed, 41 insertions, 7 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d38383f..df7d3e8 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2012-05-30  Richard Guenther  <rguenther@suse.de>
+
+	PR middle-end/53501
+	* fold-const.c (fold_binary_loc): Make sure to call
+	fold_plusminus_mult_expr with the original sign of operands.
+
 2012-05-30  Steven Bosscher  <steven@gcc.gnu.org>
 
 	* Makefile.in: Fix many dependencies.
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 8a54810..64a0d7f 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -10045,12 +10045,12 @@ fold_binary_loc (location_t loc,
       /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
 	 same or one.  Make sure type is not saturating.
 	 fold_plusminus_mult_expr will re-associate.  */
-      if ((TREE_CODE (arg0) == MULT_EXPR
-	   || TREE_CODE (arg1) == MULT_EXPR)
+      if ((TREE_CODE (op0) == MULT_EXPR
+	   || TREE_CODE (op1) == MULT_EXPR)
 	  && !TYPE_SATURATING (type)
 	  && (!FLOAT_TYPE_P (type) || flag_associative_math))
         {
-	  tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
+	  tree tem = fold_plusminus_mult_expr (loc, code, type, op0, op1);
 	  if (tem)
 	    return tem;
 	}
@@ -10668,12 +10668,12 @@ fold_binary_loc (location_t loc,
       /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
 	 same or one.  Make sure type is not saturating.
 	 fold_plusminus_mult_expr will re-associate.  */
-      if ((TREE_CODE (arg0) == MULT_EXPR
-	   || TREE_CODE (arg1) == MULT_EXPR)
+      if ((TREE_CODE (op0) == MULT_EXPR
+	   || TREE_CODE (op1) == MULT_EXPR)
 	  && !TYPE_SATURATING (type)
 	  && (!FLOAT_TYPE_P (type) || flag_associative_math))
         {
-	  tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
+	  tree tem = fold_plusminus_mult_expr (loc, code, type, op0, op1);
 	  if (tem)
 	    return tem;
 	}
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 4e53d2f..49d88e7 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2012-05-30  Richard Guenther  <rguenther@suse.de>
+
+	PR middle-end/53501
+	* gcc.dg/torture/pr53501.c: New testcase.
+	* c-c++-common/restrict-2.c: Adjust.
+
 2012-05-30  Alan Modra  <amodra@gmail.com>
 
 	* gcc.target/powerpc/powerpc.exp: Load torture-options.exp, call
diff --git a/gcc/testsuite/c-c++-common/restrict-2.c b/gcc/testsuite/c-c++-common/restrict-2.c
index 3f71b77..42ed398 100644
--- a/gcc/testsuite/c-c++-common/restrict-2.c
+++ b/gcc/testsuite/c-c++-common/restrict-2.c
@@ -10,5 +10,5 @@ void foo (float * __restrict__ a, float * __restrict__ b, int n, int j)
 
 /* We should move the RHS of the store out of the loop.  */
 
-/* { dg-final { scan-tree-dump-times "Moving statement" 11 "lim1" } } */
+/* { dg-final { scan-tree-dump-times "Moving statement" 10 "lim1" } } */
 /* { dg-final { cleanup-tree-dump "lim1" } } */
diff --git a/gcc/testsuite/gcc.dg/torture/pr53501.c b/gcc/testsuite/gcc.dg/torture/pr53501.c
new file mode 100644
index 0000000..36e3ae6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr53501.c
@@ -0,0 +1,22 @@
+/* { dg-do run } */
+
+extern void abort (void);
+
+int e[100], n, here;
+
+void __attribute__((noinline))
+foo(void)
+{
+  int i, k = 0;
+  for (i = 0; i < n; ++i) { e[k] = 10; ++k; e[k] = 10; ++k; }
+  for (i = 0; i < k; ++i) here = 1;
+  if (here != 1)
+    abort ();
+}
+
+int main(void)
+{
+  n = 10;
+  foo();
+  return 0;
+}