This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
[PATCH] Fix normal_inner_ref expansion (PR middle-end/69909)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: Richard Biener <rguenther at suse dot de>, Jeff Law <law at redhat dot com>, Bernd Schmidt <bschmidt at redhat dot com>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Tue, 23 Feb 2016 16:43:44 +0100
- Subject: [PATCH] Fix normal_inner_ref expansion (PR middle-end/69909)
- Authentication-results: sourceware.org; auth=none
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
When the base of a handled component (BIT_FIELD_REF in the testcase)
is SSA_NAME which happens to be expanded as some MEM (on the testcase
it is SSA_NAME set to VIEW_CONVERT_EXPR of an SSA_NAME that has MEM as
DECL_RTL), expand_expr_real_1 can try to update the MEM attributes from
exp, but that is wrong, it might change the alias set of the MEM, etc.
If the base is SSA_NAME, we should keep the attributes unmodified.
The patch actually also tests for !MEM_P (orig_op0), so that if
the SSA_NAME expanded to non-MEM (e.g. constant or REG), but the
normal_inner_ref expansion forces it for whatever reason in memory,
we still set the attributes of such a MEM, it is a temporary in that
case, rather than the original read.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2016-02-23 Jakub Jelinek <jakub@redhat.com>
Richard Biener <rguenth@suse.de>
PR middle-end/69909
* expr.c (expand_expr_real_1) <normal_inner_ref>: Avoid
set_mem_attributes if tem is SSA_NAME which got expanded
as a MEM.
* gcc.dg/torture/pr69909.c: New test.
--- gcc/expr.c.jj 2016-02-23 13:54:02.000000000 +0100
+++ gcc/expr.c 2016-02-23 14:30:23.810657866 +0100
@@ -10521,7 +10521,11 @@ expand_expr_real_1 (tree exp, rtx target
if (op0 == orig_op0)
op0 = copy_rtx (op0);
- set_mem_attributes (op0, exp, 0);
+ /* Don't set memory attributes if the base expression is
+ SSA_NAME that got expanded as a MEM. In that case, we should
+ just honor its original memory attributes. */
+ if (TREE_CODE (tem) != SSA_NAME || !MEM_P (orig_op0))
+ set_mem_attributes (op0, exp, 0);
if (REG_P (XEXP (op0, 0)))
mark_reg_pointer (XEXP (op0, 0), MEM_ALIGN (op0));
--- gcc/testsuite/gcc.dg/torture/pr69909.c.jj 2016-02-23 14:25:27.819719259 +0100
+++ gcc/testsuite/gcc.dg/torture/pr69909.c 2016-02-23 14:25:27.818719272 +0100
@@ -0,0 +1,35 @@
+/* PR middle-end/69909 */
+/* { dg-do run { target int128 } } */
+/* { dg-additional-options "-w" } */
+
+typedef unsigned V __attribute__ ((vector_size (32)));
+typedef __int128 T;
+typedef __int128 U __attribute__ ((vector_size (32)));
+
+__attribute__((noinline, noclone)) T
+foo (T a, V b, V c, V d, V e, U f)
+{
+ d[6] ^= 0x10;
+ f -= (U) d;
+ f[1] |= f[1] << (a & 127);
+ c ^= d;
+ return b[7] + c[2] + c[2] + d[6] + e[2] + f[1];
+}
+
+int
+main ()
+{
+ if (__CHAR_BIT__ != 8 || sizeof (unsigned) != 4 || sizeof (T) != 16)
+ return 0;
+
+ T x = foo (1, (V) { 9, 2, 5, 8, 1, 2, 9, 3 },
+ (V) { 1, 2, 3, 4, 5, 6, 7, 8 },
+ (V) { 4, 1, 2, 9, 8, 3, 5, 2 },
+ (V) { 3, 6, 1, 3, 2, 9, 4, 8 }, (U) { 3, 5 });
+ if (((unsigned long long) (x >> 64) != 0xffffffffffffffffULL
+ || (unsigned long long) x != 0xfffffffe0000001aULL)
+ && ((unsigned long long) (x >> 64) != 0xfffffffffffffffdULL
+ || (unsigned long long) x != 0xffffffff00000022ULL))
+ __builtin_abort ();
+ return 0;
+}
Jakub