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    SubjectRe: [PATCH 7/10] local_t : powerpc
    * Paul Mackerras (paulus@samba.org) wrote:
    > Mathieu Desnoyers writes:
    >
    > > +static __inline__ int local_dec_if_positive(local_t *l)
    > > +{
    > > + int t;
    > > +
    > > + __asm__ __volatile__(
    > > +"1: lwarx %0,0,%1 # local_dec_if_positive\n\
    > > + addic. %0,%0,-1\n\
    > > + blt- 2f\n"
    > > + PPC405_ERR77(0,%1)
    > > +" stwcx. %0,0,%1\n\
    > > + bne- 1b"
    >
    > This has the same bugs that we fixed recently in atomic_dec_if_positive;
    > first, on 64-bit machines, the lwarx will zero-extend the word loaded
    > from memory, and so the result of the addic will be negative only if
    > the word was originally 0. Secondly, even on 32-bit machines,
    > 0x80000000 will be considered positive since decrementing it gives
    > 0x7fffffff, which is positive.
    >
    Hi Paul,

    Thanks, will fix.

    Mathieu

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