From: Richard Biener <rguenther@suse.de>
To: gcc-patches@gcc.gnu.org
Subject: [PATCH] middle-end/107115 - avoid bogus redundant store removal during RTL expansion
Date: Thu, 6 Oct 2022 12:19:53 +0000 (UTC) [thread overview]
Message-ID: <20221006121953.lV9xAlAB5PyR-m3G9jszS7nGoRO09JeR65QI3O6NBBk@z> (raw)
The following preserves the (premature) redundant store removal
done in store_expr by appropriately guarding it with
mems_same_for_tbaa_p. The testcase added needs scheduling disabled
for now since there's a similar bug there still present.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
PR middle-end/107115
* expr.cc (store_expr): Check mems_same_for_tbaa_p before
eliding a seemingly redundant store.
* gcc.dg/torture/pr107115.c: New testcase.
---
gcc/expr.cc | 4 ++-
gcc/testsuite/gcc.dg/torture/pr107115.c | 37 +++++++++++++++++++++++++
2 files changed, 40 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/torture/pr107115.c
diff --git a/gcc/expr.cc b/gcc/expr.cc
index 80bb1b8a4c5..ba627f176a7 100644
--- a/gcc/expr.cc
+++ b/gcc/expr.cc
@@ -6207,7 +6207,9 @@ store_expr (tree exp, rtx target, int call_param_p,
if ((! rtx_equal_p (temp, target)
|| (temp != target && (side_effects_p (temp)
- || side_effects_p (target))))
+ || side_effects_p (target)
+ || (MEM_P (temp)
+ && !mems_same_for_tbaa_p (temp, target)))))
&& TREE_CODE (exp) != ERROR_MARK
/* If store_expr stores a DECL whose DECL_RTL(exp) == TARGET,
but TARGET is not valid memory reference, TEMP will differ
diff --git a/gcc/testsuite/gcc.dg/torture/pr107115.c b/gcc/testsuite/gcc.dg/torture/pr107115.c
new file mode 100644
index 00000000000..5f7b6ff01e1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr107115.c
@@ -0,0 +1,37 @@
+/* { dg-do run } */
+/* PR/107115 */
+/* { dg-additional-options "-fno-schedule-insns -fno-schedule-insns2" } */
+
+#include <stdlib.h>
+
+void test1(long *p1)
+{
+ p1[0] = 1;
+}
+long test2(long long *p2, int index1, int index2)
+{
+ p2[index1] = 2;
+ return p2[index2];
+}
+long test3(long *p3, int index2, long value)
+{
+ p3[index2] = 3;
+ p3[index2] = value;
+ return p3[0];
+}
+long test4(void *p4, int index1, int index2)
+{
+ test1(p4);
+ long temp = test2(p4, index1, index2);
+ return test3(p4, index2, temp);
+}
+long (*volatile vtest)(void *, int, int) = test4;
+int main(void)
+{
+ void *pp = malloc(sizeof (long) + sizeof(long long));
+ if (!pp) abort();
+ long result = vtest(pp, 0, 0);
+ if (*(long *)pp != 2 || result != 2)
+ __builtin_abort ();
+ return 0;
+}
--
2.35.3
reply other threads:[~2022-10-06 12:19 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20221006121953.lV9xAlAB5PyR-m3G9jszS7nGoRO09JeR65QI3O6NBBk@z \
--to=rguenther@suse.de \
--cc=gcc-patches@gcc.gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).