https://gcc.gnu.org/bugzilla/show_bug.cgi?id=36503

Eric Gallager <egallager at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |egallager at gcc dot gnu.org

--- Comment #10 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to UroŇ° Bizjak from comment #7)
> Created attachment 21972 [details]
> Patch that implements suggested optimization
> 
> Attached patch compiles the test from comment #0 to the proposed code:
> 
> int test (int a, int b)
> {
>   return a >> (32 - b);
> }
> 
> -O2 -m32:
> 
>       movl    8(%esp), %ecx
>       movl    4(%esp), %eax
>       negl    %ecx
>       sarl    %cl, %eax
>       ret
> 
> -O2 -m64:
> 
>       negl    %esi
>       movl    %edi, %eax
>       movl    %esi, %ecx
>       sarl    %cl, %eax
>       ret

Please send the patch to the gcc-patches mailing list if it still applies and
works. And change the status to ASSIGNED if you're still working on it.

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