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__sync_bool_compare_and_swap


I got so happy when __sync_bool_compare_and_swap showed up in 4.1 but
now HEAD have changed the behaviour for me.

Earlier I got (gcc version 4.1.2 20061028 (prerelease) (Debian
4.1.1-19)) (Yes, vendor version, but gcc.gnu.org versions did the same)

        lock
        cmpxchgl        %edx, (%ecx)

but now I get (gcc version 4.3.0 20070105 (experimental)) (rev 120486
(this would be interesting in the output of gcc -v, is there a way to
put the revision there?))

        call    __sync_bool_compare_and_swap_4

Now, reading the manual suggests that if I use the wrong architecture I
should get a call of this form but since the code I used was

int main()
{
        int a;
        return __sync_bool_compare_and_swap(&a, 0, 1);
}

I think it should generate the cmpxchgl.

/MF


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