diff mbox

Fix PR67442

Message ID alpine.LSU.2.11.1509160923010.24931@zhemvz.fhfr.qr
State New
Headers show

Commit Message

Richard Biener Sept. 16, 2015, 7:23 a.m. UTC 
This fixes PR67442, wide_int_to_tree used for type extension from
a different signed value (which doesn't work).

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied on trunk.

Richard.

2015-09-16  Richard Biener  <rguenther@suse.de>

	PR middle-end/67442
	* fold-const.c (extract_muldiv_1): Properly extend multiplication
	result before builting a tree via wide_int_to_tree.

	* gcc.dg/torture/pr67442.c: New testcase.
diff mbox

Patch

Index: gcc/fold-const.c
===================================================================
--- gcc/fold-const.c	(revision 227779)
+++ gcc/fold-const.c	(working copy)
@@ -6166,8 +6173,12 @@  extract_muldiv_1 (tree t, tree c, enum t
 	      && ((sign == UNSIGNED && tcode != MULT_EXPR) || sign == SIGNED))
 	    overflow_p = true;
 	  if (!overflow_p)
-	    return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
-				wide_int_to_tree (ctype, mul));
+	    {
+	      mul = wide_int::from (mul, TYPE_PRECISION (ctype),
+				    TYPE_SIGN (TREE_TYPE (op1)));
+	      return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
+				  wide_int_to_tree (ctype, mul));
+	    }
 	}
 
       /* If these operations "cancel" each other, we have the main
Index: gcc/testsuite/gcc.dg/torture/pr67442.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/pr67442.c	(revision 0)
+++ gcc/testsuite/gcc.dg/torture/pr67442.c	(working copy)
@@ -0,0 +1,12 @@ 
+/* { dg-do run } */
+
+short foo[100];
+
+int main()
+{
+  short* bar = &foo[50];
+  short i = 1;
+  short j = 1;
+  short value = bar[8 - i * 2 * j];
+  return value;
+}