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[PATCH] Fix fold-const.c (operand_equal_p)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: Richard Henderson <rth at redhat dot com>
- Cc: gcc-patches at gcc dot gnu dot org, Joe Orton <jorton at redhat dot com>
- Date: Tue, 31 Aug 2004 17:35:42 -0400
- Subject: [PATCH] Fix fold-const.c (operand_equal_p)
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
The testcase below is miscompiled on the trunk on x86-64 and ia64 at least
and on 3.4 branch on ia64.
The problem is that fold "optimizes" the ?: into
(unsigned long) d
and d is out of range of the unsigned type (it is negative).
The following patch fixes this for me (in this case it is FIX_TRUNC_EXPR,
but I believe for the other FIX_*_EXPR trees the signedness matters as
well).
Ok to commit?
For 3.4 as well?
2004-08-31 Jakub Jelinek <jakub@redhat.com>
* fold-const.c (operand_equal_p): Require equal sign also for
FIX_{CEIL,TRUNC,FLOOR,ROUND}_EXPR.
* gcc.c-torture/execute/20040831-1.c: New test.
--- gcc/fold-const.c.jj 2004-08-31 13:55:58.000000000 +0200
+++ gcc/fold-const.c 2004-08-31 23:20:12.007971792 +0200
@@ -2391,10 +2391,21 @@ operand_equal_p (tree arg0, tree arg1, u
{
case '1':
/* Two conversions are equal only if signedness and modes match. */
- if ((TREE_CODE (arg0) == NOP_EXPR || TREE_CODE (arg0) == CONVERT_EXPR)
- && (TYPE_UNSIGNED (TREE_TYPE (arg0))
- != TYPE_UNSIGNED (TREE_TYPE (arg1))))
- return 0;
+ switch (TREE_CODE (arg0))
+ {
+ case NOP_EXPR:
+ case CONVERT_EXPR:
+ case FIX_CEIL_EXPR:
+ case FIX_TRUNC_EXPR:
+ case FIX_FLOOR_EXPR:
+ case FIX_ROUND_EXPR:
+ if (TYPE_UNSIGNED (TREE_TYPE (arg0))
+ != TYPE_UNSIGNED (TREE_TYPE (arg1)))
+ return 0;
+ break;
+ default:
+ break;
+ }
return operand_equal_p (TREE_OPERAND (arg0, 0),
TREE_OPERAND (arg1, 0), flags);
--- gcc/testsuite/gcc.c-torture/execute/20040831-1.c.jj 2004-08-31 23:23:53.043250724 +0200
+++ gcc/testsuite/gcc.c-torture/execute/20040831-1.c 2004-08-31 23:25:42.558057188 +0200
@@ -0,0 +1,14 @@
+/* This testcase was being miscompiled, because operand_equal_p
+ returned that (unsigned long) d and (long) d are equal. */
+extern void abort (void);
+extern void exit (int);
+
+int
+main (void)
+{
+ double d = -12.0;
+ long l = (d > 10000) ? (unsigned long) d : (long) d;
+ if (l != -12)
+ abort ();
+ exit (0);
+}
Jakub