From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 7888) id A5B0B3858D1E; Wed, 22 May 2024 02:27:15 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org A5B0B3858D1E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1716344835; bh=iMZozypVVbFv7zjnFvbLSSg0ikq/zG9F3214C0NRvlY=; h=From:To:Subject:Date:From; b=RhrCl69x0E3HQs7q6oeVtDC4cbRp4kK3pNZYz9vdMnUrDPkzyo8R/YjK6vktSlnHr 1GWBHhGmuVgUbIdZWwcU4S3L+5tWKczXdvyA74009STNLv+nIG5ltYrTSyFy2n6/5U 3Y1yIgSH9GllJF/Iyyh3g0WvXYZ5mKgp1AoL0I1A= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Haochen Jiang To: gcc-cvs@gcc.gnu.org Subject: [gcc r14-10229] i386: Disable ix86_expand_vecop_qihi2 when !TARGET_AVX512BW X-Act-Checkin: gcc X-Git-Author: Haochen Jiang X-Git-Refname: refs/heads/releases/gcc-14 X-Git-Oldrev: d2f427951679d4a8b2d1ed73fa89bff7ced66bf9 X-Git-Newrev: 1ad5c9d524d8fa99773045e75da04ae958012085 Message-Id: <20240522022715.A5B0B3858D1E@sourceware.org> Date: Wed, 22 May 2024 02:27:15 +0000 (GMT) List-Id: https://gcc.gnu.org/g:1ad5c9d524d8fa99773045e75da04ae958012085 commit r14-10229-g1ad5c9d524d8fa99773045e75da04ae958012085 Author: Haochen Jiang Date: Tue May 21 14:10:43 2024 +0800 i386: Disable ix86_expand_vecop_qihi2 when !TARGET_AVX512BW Since vpermq is really slow, we should avoid using it for permutation when vpmovwb is not available (needs AVX512BW) for ix86_expand_vecop_qihi2 and fall back to ix86_expand_vecop_qihi. gcc/ChangeLog: PR target/115069 * config/i386/i386-expand.cc (ix86_expand_vecop_qihi2): Do not enable the optimization when AVX512BW is not enabled. gcc/testsuite/ChangeLog: PR target/115069 * gcc.target/i386/pr115069.c: New. Diff: --- gcc/config/i386/i386-expand.cc | 7 +++++++ gcc/testsuite/gcc.target/i386/pr115069.c | 9 +++++++++ 2 files changed, 16 insertions(+) diff --git a/gcc/config/i386/i386-expand.cc b/gcc/config/i386/i386-expand.cc index 8bb8f21e686..51efe6fdd7d 100644 --- a/gcc/config/i386/i386-expand.cc +++ b/gcc/config/i386/i386-expand.cc @@ -23963,6 +23963,13 @@ ix86_expand_vecop_qihi2 (enum rtx_code code, rtx dest, rtx op1, rtx op2) bool op2vec = GET_MODE_CLASS (GET_MODE (op2)) == MODE_VECTOR_INT; bool uns_p = code != ASHIFTRT; + /* Without VPMOVWB (provided by AVX512BW ISA), the expansion uses the + generic permutation to merge the data back into the right place. This + permutation results in VPERMQ, which is slow, so better fall back to + ix86_expand_vecop_qihi. */ + if (!TARGET_AVX512BW) + return false; + if ((qimode == V16QImode && !TARGET_AVX2) || (qimode == V32QImode && (!TARGET_AVX512BW || !TARGET_EVEX512)) /* There are no V64HImode instructions. */ diff --git a/gcc/testsuite/gcc.target/i386/pr115069.c b/gcc/testsuite/gcc.target/i386/pr115069.c new file mode 100644 index 00000000000..50a3e033079 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr115069.c @@ -0,0 +1,9 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mavx2" } */ +/* { dg-final { scan-assembler-not "vpermq" } } */ + +typedef char v16qi __attribute__((vector_size(16))); + +v16qi foo (v16qi a, v16qi b) { + return a * b; +}