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Re: [PATCH] improves exp() and expf() performance on Sparc.


You're defining ifuncs for exp and expf (rather than __ieee754_exp, 
__exp_finite etc. as on x86_64).  But you're not doing anything to stop 
the w_exp_compat / w_expf_compat wrappers from being built that also 
define exp and expf, so I don't see how that can work without ending up 
with multiple definitions of exp and expf; I'd expect you to need to 
override the wrappers with empty files in such a case of a function 
implementation with all the error handling integrated.

I'm also concerned that you have local matherr handling which is not 
compatible with all the cases in __kernel_standard (which are not well 
tested).  If you need to have your own integrated error handling for 
performance reasons, matherr handling should be bug-compatible with the 
existing code, for both overflow and underflow.  (Or define a new symbol 
version, make the existing exp and expf into compat symbols for SPARC and 
then your new version only needs to handle errno setting, not matherr.)

-- 
Joseph S. Myers
joseph@codesourcery.com


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