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Re: Should -fcross-jumping be part of -O1?
Robert Dewar wrote:
We are not talking minor slow downs here, but slow downs by a
significant factor (which can easily be 2 or 3). Many users of fpt
cannot even consider this level of inefficiency.
We would consider it, and then choose the alternative that's faster.
One of the most interesting quotes I read from Kahan is that
(paraphrased): Users of Cray hardware don't care - their software is
robust even against the cavalier approach of Cray floating point arithmetic.
Of course, this is the wrong way around: Cray flourished with its
five-ulp off division because the crowd that could effort a Cray had
codes that didn't _need_ the foregone exactness.
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