Re: kernel + gcc 4.1 = several problems

[Segher Boessenkool <segher@kernel.crashing.org>]

> I want this:
>
> char v[4];
> ...
> 	memcmp(v, "abcd", 4) == 0
>
> compile to single cmpl on i386. This (gcc 4.1.1) is ridiculous:

>         call    memcmp

i686-linux-gcc (GCC) 4.2.0 20060410 (experimental)

        movl    $4, %ecx        #, tmp65
        cld
        movl    $v, %esi        #, tmp63
        movl    $.LC0, %edi     #, tmp64
        repz
        cmpsb
        sete    %al     #, tmp68

Still not perfect, but better already.  If you have any
specific examples that you'd like to have compiled to
better code, please report them in GCC bugzilla (with a
self-contained testcase, please).


Segher

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