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[PATCH] Handle VCE in mf_xform_derefs_1 (PR libmudflap/36397)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: gcc-patches at gcc dot gnu dot org
- Date: Mon, 15 Sep 2008 06:55:19 -0400
- Subject: [PATCH] Handle VCE in mf_xform_derefs_1 (PR libmudflap/36397)
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
This patch handles VCE in mf_xform_derefs_1 instead of aborting on it.
If It is a VCE of constant mf_xform_derefs_1 doesn't handle, it won't
be interesting to mudflap anyway, so it just returns immediately instead
of failing assertion in the next iteration. Otherwise it looks through
the VCE.
Tested on x86_64-linux, ok for trunk?
2008-09-15 Jakub Jelinek <jakub@redhat.com>
PR libmudflap/36397
* tree-mudflap.c (mf_xform_derefs_1): Handle VIEW_CONVERT_EXPR.
* testsuite/libmudflap.c/pass64-frag.c: New test.
--- gcc/tree-mudflap.c.jj 2008-09-05 12:56:32.000000000 +0200
+++ gcc/tree-mudflap.c 2008-09-15 11:58:08.000000000 +0200
@@ -773,6 +773,13 @@ mf_xform_derefs_1 (gimple_stmt_iterator
base = TREE_OPERAND (var, 0);
break;
}
+ else if (TREE_CODE (var) == VIEW_CONVERT_EXPR)
+ {
+ var = TREE_OPERAND (var, 0);
+ if (CONSTANT_CLASS_P (var)
+ && TREE_CODE (var) != STRING_CST)
+ return;
+ }
else
{
gcc_assert (TREE_CODE (var) == VAR_DECL
--- libmudflap/testsuite/libmudflap.c/pass64-frag.c.jj 2008-09-15 12:14:28.000000000 +0200
+++ libmudflap/testsuite/libmudflap.c/pass64-frag.c 2008-09-15 12:16:17.000000000 +0200
@@ -0,0 +1,37 @@
+/* PR libmudflap/36397 */
+/* { dg-do run } */
+/* { dg-options "-O -fmudflap -fno-strict-aliasing -lmudflap" } */
+
+struct A
+{
+ int a[2];
+};
+
+long long int x;
+
+int __attribute__ ((noinline))
+baz (long long int *x)
+{
+ return *x;
+}
+
+int __attribute__ ((noinline))
+foo (int i)
+{
+ if (i > 10)
+ return baz (&x);
+ return ((struct A *) &x)->a[i];
+}
+
+int
+main (void)
+{
+ if (sizeof (long long) == 2 * sizeof (int) == sizeof (struct A))
+ {
+ struct A a = { .a[0] = 10, .a[1] = 20 };
+ __builtin_memcpy (&x, &a, sizeof (x));
+ if (foo (0) != 10 || foo (1) != 20)
+ __builtin_abort ();
+ }
+ return 0;
+}
Jakub