From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id B861F3858D39; Wed, 13 Sep 2023 13:03:35 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B861F3858D39 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1694610215; bh=GZGtSfL25spE5QzQAkIKsB4jPxMGiAzCOtwU1saqW7Q=; h=From:To:Subject:Date:In-Reply-To:References:From; b=VQNoAqZfd2YXAn3N8yWbtM0ae7VWEPDaf2KiNrkDO5PQ1356sAYXBrMu4qxezvwPD 9B2JtqoczXxfmG2liYJmbuUvITVXWZw8qfvKA7oY4TXd6W1YcSvjn3n4vgkTkUNoiy +XfgWekOsm80UNfjLg6NYOUfrlgdt/q5f4KiT45s= From: "rdapp at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/111153] RISC-V: Incorrect Vector cost model for reduction Date: Wed, 13 Sep 2023 13:03:35 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Version: 14.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: rdapp at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED 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=3D111153 --- Comment #4 from Robin Dapp --- Yes, with VLS reduction this will improve. On aarch64 + sve I see loop inside costs: 2 This is similar to our VLS costs. And their loop is indeed short: ld1w z30.s, p7/z, [x0, x2, lsl 2] add x2, x2, x3 add z31.s, p7/m, z31.s, z30.s whilelo p7.s, w2, w1 b.any .L3 Not much to be squeezed out with a VLS approach. I guess that's why.=