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Re: [PATCH] Perform constant folding of math builtins
> From: Gabriel Dos Reis <gdr@integrable-solutions.net>
>
> "Kaveh R. Ghazi" <ghazi@caip.rutgers.edu> writes:
>
> | Assuming I remembered everything correctly, these are mathematical
> | identities. But I'm not sure which if any are valid/invalid in the
> | presence of NaNs, etc.
>
> Well, I'm not sure we want to restart the discussion about what
> -funsafe-transformations should mean, but if we were to consider all
> those mentioned transformations (which are valid under appropriate
> conditions) I think we ought to clearly state what we want
> -funsae-transformation to do.
> -- Gaby
The descriptions of the various fast math flags in invoke.texi
(including -funsafe-math-optimizations if that's what you meant) are
all pretty explicit and clear IMHO.
What remains seems to be to decide under which of these flags (or
always/never) are each of the pow optimizations valid, not what the
flags mean. If an FP expert would comment on that, I'd be grateful.
Thanks,
--Kaveh
--
Kaveh R. Ghazi Director of Systems Architecture
ghazi@caip.rutgers.edu Qwest Solutions