*BSD News Article 5116


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Path: sserve!manuel!munnari.oz.au!uunet!mcsun!Germany.EU.net!bs
From: bs@Germany.EU.net (Bernard Steiner)
Newsgroups: comp.unix.bsd
Subject: Re: 386bsd Xfree
Date: 16 Sep 1992 15:02:17 GMT
Organization: EUnet Backbone, Dortmund, Germany
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References: <1949s2INNrmp@disaster.Germany.EU.net> <JTSILLA.92Sep15125721@damon.ccs.northeastern.edu>
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In article <JTSILLA.92Sep15125721@damon.ccs.northeastern.edu>, jtsilla@damon.ccs.northeastern.edu (James Tsillas) writes:
> There's no need to recompile since the math emulation is done through
> software traps when FPU instructions are found. If you have a 486 or a
> 387 then you never get an FPU trap and the FPU instruction is handled by
> the hardware.

Excusez-moi, I beg to differ.
Programs compiled with the standard libm.a emulate all the fsqrt,fgsin,fcos
and what have you by fmul, fdiv, fadd and fsub. Those are the only instructions
emulated by the emulator in the kernel.
Re-linking with a math library that actually uses fsin etc would probably
improve performance; except when the only stuff actually used by X11 was
the four above-mentioned basic instructions.

Greetings,
	Bernard
-- 
Bernard Steiner, FB Informatik/IRB, Uni Dortmund,    vox +49 231 755 2444
Postfach 500500, D-W-4600 Dortmund 50, Germany       fax +49 231 755 2386
bs@Germany.EU.net          ...!uunet!unido!bs

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