From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id AC0913858D28; Fri, 22 Mar 2024 08:07:22 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org AC0913858D28 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1711094842; bh=BflbV2RR5NwReXc5cXKmU9jN0MFlcqebZYV6AQYS2Ok=; h=From:To:Subject:Date:In-Reply-To:References:From; b=OlsqzdYJHj/0pj1GMwe0p1SceJUNut26BXkwDlmO1jl8fAb9sr1uRYOBBVN8OEn2N 4/PobdRtyNAQbJwzfTHq3BLKQoqiuY+kKpAVQaEKCkgiDCPmI+yRNJGWQOeY81a4tW Dd5USnPyc2lWzbZUmmD4u6QHh3sW/6db9z1FXs+4= From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/101523] Huge number of combine attempts Date: Fri, 22 Mar 2024 08:07:16 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Version: 12.0 X-Bugzilla-Keywords: compile-time-hog, memory-hog X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: segher at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cf_known_to_fail everconfirmed cf_reconfirmed_on bug_status Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101523 Richard Biener changed: What |Removed |Added ---------------------------------------------------------------------------- Known to fail| |14.0 Ever confirmed|0 |1 Last reconfirmed| |2024-03-22 Status|UNCONFIRMED |NEW --- Comment #42 from Richard Biener --- I checked with a cross btw, and with -O1 we use 10s and 900MB memory for the testcase for comment #22. With -O2 it's 160s and 11GB as reported. It might of course that with -O1 we simply do not confront combine with the opportunity to blow up. So IMHO this is a non-issue and the reporter should use -O1 for such a TU. Still confirmed as a s390x specific problem and confirmed on trunk. Statistics with the -O2 combines: 305 combine "successes" 9425=20 305 combine "three-insn combine" 1 305 combine "four-insn combine" 1 305 combine "merges" 40418007=20 305 combine "extras" 9110287 305 combine "two-insn combine" 9423 305 combine "attempts" 40440004 With -O1: 305 combine "successes" 1861 305 combine "three-insn combine" 1732 305 combine "merges" 191051 305 combine "extras" 9274 305 combine "two-insn combine" 129 305 combine "attempts" 192434=