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Re: [PATCH] v11 Improves __ieee754_exp() performance by greater than 5x on sparc/x86.
On Tue, 13 Feb 2018, Patrick McGehearty wrote:
> Any thoughts on general principles on how to decide which patch
> to accept, given both seem much more better than the existing code?
My understanding would be that Szabolcs intends (as per
<https://sourceware.org/ml/libc-alpha/2018-02/msg00065.html> and
<https://sourceware.org/ml/libc-alpha/2018-02/msg00061.html>) to eliminate
rounding mode changes from the present exp, and possibly make other
speedups there. Then the final result of such speedups would need
comparing with a version of your patch that also eliminates rounding mode
changes (and updates libm-test-ulps expectations for other functions in
non-default rounding modes as needed to avoid introducing failures). It
would be best to have a precise statement of what "both my throughput and
latency benchmarks" are in
<https://sourceware.org/ml/libc-alpha/2018-02/msg00061.html>, to make sure
there is a common basis of comparison so we can see if it's really the
case that one version is faster on some architectures and another on other
architectures, or whether different people are measuring different things.
--
Joseph S. Myers
joseph@codesourcery.com