This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH] Fix PR66142
- From: Kyrill Tkachov <kyrylo dot tkachov at arm dot com>
- To: Richard Biener <rguenther at suse dot de>, "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Date: Wed, 27 May 2015 17:00:53 +0100
- Subject: Re: [PATCH] Fix PR66142
- Authentication-results: sourceware.org; auth=none
- References: <alpine dot LSU dot 2 dot 11 dot 1505261553270 dot 30088 at zhemvz dot fhfr dot qr>
Hi Richard,
On 26/05/15 14:54, Richard Biener wrote:
The following fixes the testcase in PR66142
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.
Richard.
2015-05-26 Richard Biener <rguenther@suse.de>
PR tree-optimization/66142
* tree-ssa-sccvn.c (vn_reference_lookup_3): Manually compare
MEM_REFs for the same base address.
* gcc.dg/tree-ssa/ssa-fre-44.c: New testcase.
Index: gcc/tree-ssa-sccvn.c
===================================================================
--- gcc/tree-ssa-sccvn.c (revision 223574)
+++ gcc/tree-ssa-sccvn.c (working copy)
@@ -1894,7 +1894,12 @@ vn_reference_lookup_3 (ao_ref *ref, tree
size2 = lhs_ref.size;
maxsize2 = lhs_ref.max_size;
if (maxsize2 == -1
- || (base != base2 && !operand_equal_p (base, base2, 0))
+ || (base != base2
+ && (TREE_CODE (base) != MEM_REF
+ || TREE_CODE (base2) != MEM_REF
+ || TREE_OPERAND (base, 0) != TREE_OPERAND (base2, 0)
+ || !tree_int_cst_equal (TREE_OPERAND (base, 1),
+ TREE_OPERAND (base2, 1))))
|| offset2 > offset
|| offset2 + size2 < offset + maxsize)
return (void *)-1;
Index: gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-44.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-44.c (revision 0)
+++ gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-44.c (working copy)
@@ -0,0 +1,62 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-fre1" } */
+
+struct A { float x, y; };
+struct B { struct A u; };
+void bar (struct A *);
+
+float
+f1 (struct B *x, int y)
+{
+ struct A p;
+ p.x = 1.0f;
+ p.y = 2.0f;
+ struct A *q = &x[y].u;
+ *q = p;
+ float f = x[y].u.x + x[y].u.y;
+ bar (&p);
+ return f;
+}
+
+float
+f2 (struct B *x, int y)
+{
+ struct A p;
+ p.x = 1.0f;
+ p.y = 2.0f;
+ x[y].u = p;
+ float f = x[y].u.x + x[y].u.y;
+ bar (&p);
+ return f;
+}
+
+float
+f3 (struct B *x, int y)
+{
+ struct A p;
+ p.x = 1.0f;
+ p.y = 2.0f;
+ struct A *q = &x[y].u;
+ __builtin_memcpy (&q->x, &p.x, sizeof (float));
+ __builtin_memcpy (&q->y, &p.y, sizeof (float));
+ *q = p;
+ float f = x[y].u.x + x[y].u.y;
+ bar (&p);
+ return f;
+}
+
+float
+f4 (struct B *x, int y)
+{
+ struct A p;
+ p.x = 1.0f;
+ p.y = 2.0f;
+ __builtin_memcpy (&x[y].u.x, &p.x, sizeof (float));
+ __builtin_memcpy (&x[y].u.y, &p.y, sizeof (float));
+ float f = x[y].u.x + x[y].u.y;
+ bar (&p);
+ return f;
+}
I see this test failing on arm-none-eabi. In particular, the f4 dump is the only one
that doesn't contain "return 3.0". Instead it is:
f4 (struct B * x, int y)
{
float f;
struct A p;
unsigned int y.3_5;
unsigned int _6;
struct B * _8;
float * _9;
float * _14;
float _19;
float _23;
<bb 2>:
p.x = 1.0e+0;
p.y = 2.0e+0;
y.3_5 = (unsigned int) y_4(D);
_6 = y.3_5 * 8;
_8 = x_7(D) + _6;
_9 = &_8->u.x;
__builtin_memcpy (_9, &p.x, 4);
_14 = &_8->u.y;
__builtin_memcpy (_14, &p.y, 4);
_19 = _8->u.x;
_23 = _8->u.y;
f_24 = _19 + _23;
bar (&p);
p ={v} {CLOBBER};
return f_24;
}
Thanks,
Kyrill
+
+/* { dg-final { scan-tree-dump-times "return 3.0" 4 "fre1" } } */
+/* { dg-final { cleanup-tree-dump "fre1" } } */