"atomic" 64-bit math on 32-bit ppc's?

Segher Boessenkool segher at kernel.crashing.org
Thu Sep 6 23:21:36 EST 2007


>> That's wrong if lock is assigned to r0, you should use
>> a "b" constraint to avoid this. Same for atomic_dec below.
>
> GCC should really have removed r0 from the "r" class (it isn't truly a
> general-purpose register), and had a different class meaning 
> "r"-plus-r0.

Nah, GPR0 _is_ a general purpose register, you just cannot use all
general purpose registers as base registers ;-)

Either way, it's a bit late to change this, no?


Segher




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