[Bug rtl-optimization/58195] Missed optimization opportunity when returning a conditional

bisqwit at iki dot fi gcc-bugzilla@gcc.gnu.org
Tue Mar 11 13:28:00 GMT 2014


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58195

Joel Yliluoma <bisqwit at iki dot fi> changed:

           What    |Removed                     |Added
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                 CC|                            |bisqwit at iki dot fi

--- Comment #1 from Joel Yliluoma <bisqwit at iki dot fi> ---
Problem confirmed on "gcc (GCC) 4.9.0 20140303 (experimental)" (SVN version) in
both 32-bit and 64-bit mode using -Ofast.

For comparison, Clang++ produces this instead (even on -O1): 

        negl    %edi
        movl    %edi, %eax
        ret

GCC misses an optimization opportunity here.



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