From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id DC4AE3858C50; Thu, 1 Dec 2022 12:02:59 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org DC4AE3858C50 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1669896179; bh=iMIw+f3Eor+J/tU5DIrNMbYGPjOa60ijeyD/Vn7IgpU=; h=From:To:Subject:Date:In-Reply-To:References:From; b=FJM6a/X6H/RMVKIpea7rBVL0u5SqvO27VxKvfdcVWLGoRexq0P8apHOTW+WFiuwEA XtHqXb5hLSRZZ87gAgw7eHL+MT/inknxZqZsFhentlLueeX5RzzdaI4AaQRSu/1PQJ o1UeAREco/76jeEoXDANbMJuSm1eOlwKWWFV+fTM= From: "jakub at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug debug/106746] [13 Regression] '-fcompare-debug' failure (length) with -O2 -fsched2-use-superblocks since r13-2041-g6624ad73064de241 Date: Thu, 01 Dec 2022 12:02:58 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: debug X-Bugzilla-Version: 13.0 X-Bugzilla-Keywords: compare-debug-failure X-Bugzilla-Severity: normal X-Bugzilla-Who: jakub at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 13.0 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=3D106746 --- Comment #12 from Jakub Jelinek --- Alex, please correct me if I'm wrong, but I think the scheduling DEBUG_INSN decision was that DEBUG_INSNs are somehow taken into account during schedul= ing, not completely ignored, so that they actually move together with scheduling changes. I know H.J. has posted a patch to ignore for scheduling purposes everything inside of CONCAT{,N}, but the scheduler itself doesn't specifically check f= or those 2 rtxes anywhere, so I don't find anything special on them. And as h= as been tried, ignoring DEBUG_INSNs for all scheduler decisions regresses a lot (not unsuprisingly), they should be scheduled after insns which produce/sto= re what they depend on and before later insns that modify the registers/memroy used in them if possible (or reset if that would affect how non-DEBUG_INSNs are scheduled relative to each other). Though, I think DEBUG_INSNs should be treated as needing no computing resources, with 0 latencies.=