From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 56ED6385840F; Mon, 24 Jun 2024 17:04:52 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 56ED6385840F DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1719248692; bh=+kYoLUYpo+wLuEuI7sJ5NGy1buVlOwtJ/wxoHCAv3XE=; h=From:To:Subject:Date:In-Reply-To:References:From; b=tnGptNd617I/dtPq9Z8SEjLifqRqdY6P7fUOiXPAgf6spPTB7hNLUhihS8I1HZlHt T2oC+54e0SdlYCM/LHewhkbab3chpJyUoxQS0gDfW8cFXXAH+0ZvbiF7K7vdKMX+OO k/z1h7At6zW1LdItCPYDjQfCtQy9UxhEWc8giD6w= From: "andi-gcc at firstfloor dot org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/115344] Missing loop counter reversal Date: Mon, 24 Jun 2024 17:04:51 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: tree-optimization X-Bugzilla-Version: 15.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: enhancement X-Bugzilla-Who: andi-gcc at firstfloor dot 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=3D115344 --- Comment #4 from Andi Kleen --- Pedantry aside the basic problem is that doloop optimization depends on the target supporting doloop, but the loop reversal would be useful everywhere. So there are two options: add doloop to every target of interest or make the reversal optimization independent.=