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From: "liuhongt at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/114514] New: v16qi >> 7 can be optimized with vpcmpgtb
Date: Thu, 28 Mar 2024 09:38:00 +0000	[thread overview]
Message-ID: <bug-114514-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114514

            Bug ID: 114514
           Summary: v16qi >> 7 can be optimized with vpcmpgtb
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: liuhongt at gcc dot gnu.org
  Target Milestone: ---

v16qi
foo2 (v16qi a, v16qi b)
{
    return a >> 7;
}

it can be optimized with
        vpxor   xmm1, xmm1, xmm1
        vpcmpgtb        xmm0, xmm1, xmm0
        ret

currently we generate(emulated with v16hi)

        movl    $16843009, %eax
        vpsraw  $7, %xmm0, %xmm0
        vmovd   %eax, %xmm1
        vpbroadcastd    %xmm1, %xmm1
        vpandn  %xmm1, %xmm0, %xmm0
        vpsubb  %xmm1, %xmm0, %xmm0

             reply	other threads:[~2024-03-28  9:38 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-28  9:38 liuhongt at gcc dot gnu.org [this message]
2024-03-28 23:09 ` [Bug target/114514] " pinskia at gcc dot gnu.org
2024-03-28 23:14 ` pinskia at gcc dot gnu.org
2024-03-29  1:03 ` liuhongt at gcc dot gnu.org

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