From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id DC8CA3858C5F; Tue, 6 Jun 2023 12:17:34 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org DC8CA3858C5F DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1686053854; bh=7IwKEV412U0XMH2hZhZS2hVhCUNmBYEYrqK+uEG6raw=; h=From:To:Subject:Date:In-Reply-To:References:From; b=fX/qF8HbwSEcn93Zv/WS5te9u+Cy/ABYQ61Jf0LH6nlHrOmBHW9SkfsMLmHOQmh9i e7gjLUJEVcNRv4J/vHgGvIgrcIw7CVCtT5YjVskJZ7WrydRc/BlBKATi2VGLUcw7EZ XXPDJeB3Dgst3v00BumfW47wg9PaIIJ6q5GLygAU= From: "klepikov.alex+bugs at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/54089] [SH] Refactor shift patterns Date: Tue, 06 Jun 2023 12:17:32 +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: 4.8.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: enhancement X-Bugzilla-Who: klepikov.alex+bugs at gmail dot com X-Bugzilla-Status: ASSIGNED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: olegendo 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=3D54089 --- Comment #62 from Alexander Klepikov --- > I'm a bit concerned about the increased compile time. Have you observed > anything (negative) in this regard? My project is small and it compiles in under 1 second on both clean and pat= ched GCC. sh.exp test suite mean run time is 117s on clean and 119s on patched. I did 1 warm-up run and then 3 main one-threaded runs for each task. I'm thin= king of something else. >=20 > Loop, hoist, constant propagation etc (+ all the good stuff) optimizations > are done before insn combine / split1. We could add a simple SH specific > pass that goes over the RTL and does stuff to shifts before those other > optimizations. That's a good idea!=20 > However, it might miss insn combine opportunities later on.=20 Implementing features not supported by hardware will always be a tradeoff.=