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[PATCH] PR86844: Fix for store merging
- From: Andreas Krebbel <krebbel at linux dot ibm dot com>
- To: gcc-patches at gcc dot gnu dot org
- Cc: Andreas Krebbel <krebbel at linux dot vnet dot ibm dot com>
- Date: Tue, 7 Aug 2018 13:35:26 +0200
- Subject: [PATCH] PR86844: Fix for store merging
From: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Bootstrapped and regtested on s390x and x86_64.
gcc/ChangeLog:
2018-08-07 Andreas Krebbel <krebbel@linux.ibm.com>
PR tree-optimization/86844
* gimple-ssa-store-merging.c (check_no_overlap): Add a check to
reject overlaps if it has seen a non-constant store in between.
gcc/testsuite/ChangeLog:
2018-08-07 Andreas Krebbel <krebbel@linux.ibm.com>
PR tree-optimization/86844
* gcc.dg/pr86844.c: New test.
---
gcc/gimple-ssa-store-merging.c | 8 +++++++-
gcc/testsuite/gcc.dg/pr86844.c | 42 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 49 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/pr86844.c
diff --git a/gcc/gimple-ssa-store-merging.c b/gcc/gimple-ssa-store-merging.c
index 0ae4581..2abef2e 100644
--- a/gcc/gimple-ssa-store-merging.c
+++ b/gcc/gimple-ssa-store-merging.c
@@ -2401,13 +2401,19 @@ check_no_overlap (vec<store_immediate_info *> m_store_info, unsigned int i,
unsigned HOST_WIDE_INT end)
{
unsigned int len = m_store_info.length ();
+ bool seen_group_end_store_p = false;
+
for (++i; i < len; ++i)
{
store_immediate_info *info = m_store_info[i];
if (info->bitpos >= end)
break;
+ if (info->rhs_code != INTEGER_CST)
+ seen_group_end_store_p = true;
if (info->order < last_order
- && (rhs_code != INTEGER_CST || info->rhs_code != INTEGER_CST))
+ && (rhs_code != INTEGER_CST
+ || info->rhs_code != INTEGER_CST
+ || seen_group_end_store_p))
return false;
}
return true;
diff --git a/gcc/testsuite/gcc.dg/pr86844.c b/gcc/testsuite/gcc.dg/pr86844.c
new file mode 100644
index 0000000..9ef08e9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr86844.c
@@ -0,0 +1,42 @@
+/* { dg-do run } */
+/* { dg-require-effective-target stdint_types } */
+/* { dg-options "-O1 -fstore-merging" } */
+
+#include <stdint.h>
+
+struct foo
+{
+ union
+ {
+ uint32_t u4i;
+
+ struct
+ {
+ uint8_t x;
+ uint8_t y;
+ uint8_t z;
+ uint8_t w;
+ } s;
+ } u;
+ uint8_t v;
+};
+
+void __attribute__((noinline,noclone))
+f (struct foo *a)
+{
+ a->u.u4i = 0;
+ a->u.s.w = 222;
+ a->u.s.y = 129;
+ a->u.s.z = a->v;
+}
+
+int
+main ()
+{
+ struct foo s;
+
+ f (&s);
+
+ if (s.u.s.w != 222)
+ __builtin_abort ();
+}
--
2.9.1