http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56999



--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-04-18 
16:42:34 UTC ---

BTW, of course much lower priority, this also shows another spot where I think

reload code is better.



In the same ebb as the wrong-code, reload has code like:

        movl    %eax, %ecx

        shrb    $3, %cl

        andl    $1, %ecx

...

        movb    %cl, 23(%esp)

while LRA generates:

        movl    %eax, %ecx

        shrb    $3, %cl

        movb    %cl, 31(%esp)

...

        andb    $1, 31(%esp)



I'd think anding the value while we still have it in a register ought to be

better, though I admit I haven't benchmarked it.

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