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Re: s390: Avoid CAS boolean output inefficiency


On 08/07/2012 10:02 AM, Ulrich Weigand wrote:
> The following patch changes the builtin expander to pass a MEM oldval
> as-is to the back-end expander, so that the back-end can move the
> store to before the CC operation.  With that patch I'm also seeing
> all the IPMs disappear.
...
> What do you think about this solution?  It has the advantage that
> we still get the same xor code if we actually do need the ipm ...

I'm ok with that patch.


r~


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