From owner-freebsd-arch  Sat Jan 12 16: 0:34 2002
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Date: Sat, 12 Jan 2002 15:59:50 -0800 (PST)
From: John Baldwin <jhb@FreeBSD.org>
To: Peter Wemm <peter@wemm.org>
Subject: Re: Request for review: getcontext, setcontext, etc
Cc: arch@FreeBSD.ORG, Archie Cobbs <archie@dellroad.org>,
	Dan Eischen <eischen@vigrid.com>,
	Daniel Eischen <eischen@pcnet1.pcnet.com>,
	Nate Williams <nate@yogotech.com>, Kelly Yancey <kbyanc@posi.net>,
	Alfred Perlstein <bright@mu.org>,
	Terry Lambert <tlambert2@mindspring.com>,
	Bruce Evans <bde@zeta.org.au>
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On 12-Jan-02 Peter Wemm wrote:
>> The Xdna trap to do load the state if we guessed wrong about the
>> next timeslice not using the FPU takes about 200 instructions
>> including several slow ones like iret, so we don't get near 38
>> instructions in all cases although we could (Xdna can be written
>> in about 10 instructions if it doesn't go through trap() and
>> other general routines).
> 
> Hmm, that is good to know too.

And worth implementing at some point. :)

-- 

John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/

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