Date: Mon, 07 Jan 2002 13:48:17 -0800 (PST) From: John Baldwin <jhb@FreeBSD.org> To: Nate Williams <nate@yogotech.com> Cc: arch@freebsd.org, Dan Eischen <eischen@vigrid.com> Subject: Re: Request for review: getcontext, setcontext, etc Message-ID: <XFMail.020107134817.jhb@FreeBSD.org> In-Reply-To: <15418.5641.919327.356015@caddis.yogotech.com>
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On 07-Jan-02 Nate Williams wrote: >> > 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. :) > Nate -- John Baldwin <jhb@FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message
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