From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 524C13858D28; Wed, 18 Jan 2023 15:47:58 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 524C13858D28 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1674056878; bh=HCVUnpO2cibB3uvID+IZFdl7MAQYtdA3C5JHLDjHPBo=; h=From:To:Subject:Date:In-Reply-To:References:From; b=eBqFxzx7H54gHFWga665RgPi0Eib6T/qOBBHCiZD3FSZQpiz45zq+N14Svv3nvh9i VvzshFcQyKqbLrAf9+CqIdEa7HLNw8/yjeMlmwqaGh+8+kO3r/CyCBo/PeJaqX7Dub ypUh4bixgoyCvomVKuZLRAoYtYfkYCf1/pSVjZG4= From: "hubicka at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug ipa/94360] 6% run-time regression of 502.gcc_r against GCC 9 when compiled with -O2 and both PGO and LTO Date: Wed, 18 Jan 2023 15:47:57 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: ipa X-Bugzilla-Version: 10.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: hubicka at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_status cf_reconfirmed_on everconfirmed 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=3D94360 Jan Hubicka changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2023-01-18 Ever confirmed|0 |1 --- Comment #4 from Jan Hubicka --- With -O2 -fprofile-use we now use -O2 inliner limits while previously we switched to effectively -O3 inlining. In a way it makes sense to have -O2 -fprofile-use to produce smaller and bit slower code than -O3 -fprofile-use but it seems that current limits are way= too low. I.e. the code size savings does not seem to justify the performance l= oss. >From maintenance perspective it kind of sucks to have 3 sets of values (-O2, -O3 and -O2 + -fprofile-use) but maybe we can get cheaply out by simply mak= ing "known hot" hint to be taken seriously with FDO. FDO inlining is kind of e= asy since hot calls are known well. I will take a look.=