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From: Nate Williams <nate@yogotech.com>
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Date: Mon, 7 Jan 2002 14:51:24 -0700
To: John Baldwin <jhb@FreeBSD.ORG>
Cc: Nate Williams <nate@yogotech.com>, arch@FreeBSD.ORG,
	Dan Eischen <eischen@vigrid.com>
Subject: Re: Request for review: getcontext, setcontext, etc
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> >> > Also, forgive my ignorance, but why are we using fnsave instead of
> >> > fsave?  From my reading of the x86 manuals, it would seem that there is
> >> > the possibility of getting bogus FPU results with fnsave (vs. fsave)
> >> > since by using fsave, we give the FPU a chance to finish up the current
> >> > FPU operations before we save the state?  I could see where they might
> >> > be a race where we might end up storing intermediate results of the FPU
> >> > in some instances.
> >> > 
> >> > Or, is there something else I'm missing?  (The reason I ask is that the
> >> > JDK uses fsave to be 'safe', but maybe it's not buying us anything other
> >> > than warm fuzzies. :)
> >> 
> >> I don't know :-)  That's what it was using when John Birrell was
> >> maintaining libc_r.  I can always change it...
> > 
> > How about it John?  Why the use of 'fnsave' when storing FPU context
> > vs. using fsave?
> 
> Hmm, wrong John.  You want jb@ I believe. :)

Right, sorry John.


Nate

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