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From: "crazylht at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/110921] Relax _tzcnt_u32 support x86, all x86 arch
 support for this instrunction
Date: Mon, 07 Aug 2023 01:52:00 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110921

--- Comment #5 from Hongtao.liu <crazylht at gmail dot com> ---
Maybe source code can be changed as
 int f(int a, int b)
{
    #ifdef __BMI__
        return _tzcnt_u32   (a);
    #else
        return _bit_scan_forward (a);
    #endif
}

But looks like clang/MSVC doesn't support _bit_scan_forward, should be a bug
for them since it's in the intrinsics guide.=