Fix hypotf overflow/underflow (bug 13840)

[Joseph S. Myers]

On Tue, 13 Mar 2012, David Miller wrote:

> From: David Miller <davem@davemloft.net>
> Date: Tue, 13 Mar 2012 17:36:40 -0700 (PDT)
> 
> > From: David Miller <davem@davemloft.net>
> > Date: Tue, 13 Mar 2012 15:43:25 -0700 (PDT)
> > 
> >> By using a cast to double all the scaling code can be removed, and all
> >> that's left are the checks against 0x7f800000 and zero.
> > 
> > Something like this.  It passes all the existing math tests at
> > least on sparc.  I'll try with the new tests from your patch
> > Joseph.
> 
> Joseph, it passes your new tests as well.
> 
> So, feel free to check in my version if you want.

I suggest you check in your patch - it looks fine to me.  I'll then (check 
in the tests and) retest my csqrt patch with it.

-- 
Joseph S. Myers
joseph@codesourcery.com