Suboptimal code on x86

Suboptimal code on x86

[Remi Guyomarch]

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This is with snapshot 19980530 :

void foo (int) __attribute__ ((__regparm__(1)));

void foo (int bar) {
    int baz = bar*2;    
    printf ("%d %d", bar, baz);
}

with -O9 -fomit-frame-pointer give me this code :

foo:
        movl %eax,%edx	##
        movl %edx,%eax	## huh ?
        addl %edx,%eax
        pushl %eax
        pushl %edx
        pushl $.LC0
        call printf
        addl $12,%esp
        ret

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Re: Suboptimal code on x86

[Martin Kahlert]

Quoting Remi Guyomarch (rguyom@mail.dotcom.fr):
> This is with snapshot 19980530 :
> 
> void foo (int) __attribute__ ((__regparm__(1)));
> 
> void foo (int bar) {
>     int baz = bar*2;    
>     printf ("%d %d", bar, baz);
> }
> 
> with -O9 -fomit-frame-pointer give me this code :
> 
> foo:
>         movl %eax,%edx	##
>         movl %edx,%eax	## huh ?
>         addl %edx,%eax
>         pushl %eax
>         pushl %edx
>         pushl $.LC0
>         call printf
>         addl $12,%esp
>         ret

With this newer one (gcc -v):
Reading specs from /sw/egcs/lib/gcc-lib/i686-pc-linux-gnulibc1/egcs-2.91.42/specs
gcc version egcs-2.91.42 19980621 (gcc2 ss-980502 experimental)

I get:
foo:
     movl %eax,%edx
     addl %eax,%edx
     pushl %edx
     pushl %eax
     pushl $.LC0
     call printf
     addl $12,%esp
     ret

So it seems to be corrected, yet.
Martin.


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