From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 84E853858D28; Wed, 12 Apr 2023 15:43:47 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 84E853858D28 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1681314227; bh=QvX55vr1cyZcviCxgY3IqwURQHcKhSKbxMJko/oyo6w=; h=From:To:Subject:Date:In-Reply-To:References:From; b=mwUgDMUvNzfmg2kSw60Ie3uj1NQC+19FyXkt0s/Mkzld4G/3324ZSWCfZTMxeuvkT wZ8eP7UoS2EMtxvkBS4l/jTYt5pensgEUQ6QQeR4Rr/wrSqPMKpvwx0V2OTUTVUABD swj+aUOYpeD62BLeLzxLRF4SWeZhBWMALVZWHTDQ= From: "segher at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/109476] Missing optimization for 8bit/8bit multiplication / regression Date: Wed, 12 Apr 2023 15:43:47 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: rtl-optimization X-Bugzilla-Version: 12.2.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: segher 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: 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=3D109476 --- Comment #5 from Segher Boessenkool --- Correct, this certainly can not be done by combine, it see two independent pseudos here. For hard registers it *can* do many tricks, but not for pseudos like this.=