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Re: Changing the default i387 precision

On Sat, May 04, 2013 at 07:14:00AM -0400, Greg Troxel wrote:
> So are you proposing then
>   1) Make gcc and clang use larger storage (maybe already true) and avoid
>   SSE instructions for variables declared as long double?

That's already the case. long double computations always use the i387.
The point is that I want them to get the extended precision.

>   2) Add functions in libm so that instead of float/double versions we
>   will have float/double/long double versions of each function?

That is also somewhat independent and necessary for full C++11 support,
but with the current way it is almost useless as the only benefit is a
wider exponent range.


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