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Re: rs6000 fused multiply-add patch [+ patchlet]


    I don't think that anyone is objecting to the concept and the benefit.
    If I understand correctly, the patch violates the semantics of the
    combiner algorithm which requires a declining cost calculated as the
    number of instructions.  Allowing combinations that do not decrease
    the cost would make the algorithm non-deterministic and possibly not
    converge, right?

That's what I'm saying, yes.  I'm out of the country right now with poor
email access and will have more to say on this when I et bck in a few days.


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