On Sat, Aug 11, 2007 at 02:38:40AM +0200, Segher Boessenkool wrote:
> >>That means GCC cannot compile Linux; it already optimises
> >>some accesses to scalars to smaller accesses when it knows
> >>it is allowed to. Not often though, since it hardly ever
> >>helps in the cost model it employs.
> >
> >Please give an example code snippet + gcc version + arch
> >to back this up.
>
> unsigned char f(unsigned long *p)
> {
> return *p & 1;
> }
This doesn't really matter since we only care about the LSB.
Do you have an example where gcc reads it non-atmoically and
we care about all parts?
Cheers,
--
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