[Bug target/122018] x86 doesn't use BTS bitmanip instruction to both set and test bit

[uis9936 at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122018

uis <uis9936 at gmail dot com> changed:

           What    |Removed                     |Added
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  Attachment #65242|0                           |1
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--- Comment #17 from uis <uis9936 at gmail dot com> ---
Created attachment 65301
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=65301&action=edit
i386: include bit test patterns in bts, btc and btr to remove redundant bt

Works on small example code.

void g();
int f(int a, int b) {
    bool t = false;
    t = (a >> b) & 1;
    a = a | (1 << b);
    if(!t) {
        g();
    }
    return a;
}