From: Richard Biener <rguenther@suse.de>
To: gcc-patches@gcc.gnu.org
Subject: [PATCH] tree-optimization/107301 - check if we can duplicate block before doing so
Date: Tue, 18 Oct 2022 10:30:21 +0200 (CEST) [thread overview]
Message-ID: <20221018083022.2B11F139D2@imap2.suse-dmz.suse.de> (raw)
Path isolation failed to do that.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
PR tree-optimization/107301
* gimple-ssa-isolate-paths.cc (handle_return_addr_local_phi_arg):
Check whether we can duplicate the block.
(find_implicit_erroneous_behavior): Likewise.
* gcc.dg/torture/pr107301.c: New testcase.
---
gcc/gimple-ssa-isolate-paths.cc | 6 ++++--
gcc/testsuite/gcc.dg/torture/pr107301.c | 15 +++++++++++++++
2 files changed, 19 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/torture/pr107301.c
diff --git a/gcc/gimple-ssa-isolate-paths.cc b/gcc/gimple-ssa-isolate-paths.cc
index 87ecd19ef4a..e4a4e08f549 100644
--- a/gcc/gimple-ssa-isolate-paths.cc
+++ b/gcc/gimple-ssa-isolate-paths.cc
@@ -647,7 +647,8 @@ handle_return_addr_local_phi_arg (basic_block bb, basic_block duplicate,
if (!maybe
&& (flag_isolate_erroneous_paths_dereference
|| flag_isolate_erroneous_paths_attribute)
- && gimple_bb (use_stmt) == bb)
+ && gimple_bb (use_stmt) == bb
+ && (duplicate || can_duplicate_block_p (bb)))
{
duplicate = isolate_path (bb, duplicate, e,
use_stmt, lhs, true);
@@ -765,7 +766,8 @@ find_implicit_erroneous_behavior (void)
? gimple_location (use_stmt)
: phi_arg_loc;
- if (stmt_uses_name_in_undefined_way (use_stmt, lhs, loc))
+ if (stmt_uses_name_in_undefined_way (use_stmt, lhs, loc)
+ && (duplicate || can_duplicate_block_p (bb)))
{
duplicate = isolate_path (bb, duplicate, e,
use_stmt, lhs, false);
diff --git a/gcc/testsuite/gcc.dg/torture/pr107301.c b/gcc/testsuite/gcc.dg/torture/pr107301.c
new file mode 100644
index 00000000000..5f0afcc0d10
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr107301.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+
+__attribute__ ((pure, returns_twice)) int
+foo (int x)
+{
+ int a;
+
+ a = x ? 3 : 0;
+ x /= a;
+ a = foo (x);
+ if (x == a)
+ __builtin_unreachable ();
+
+ return 0;
+}
--
2.35.3
reply other threads:[~2022-10-18 8:30 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=20221018083022.2B11F139D2@imap2.suse-dmz.suse.de \
--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).