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Mail Archives: djgpp/1998/09/30/21:47:27

Message-Id: <199810010147.VAA27904@delorie.com>
Comments: Authenticated sender is <mert0407 AT sable DOT ox DOT ac DOT uk>
From: "George Foot" <george DOT foot AT merton DOT ox DOT ac DOT uk>
To: Bradley Walker <bwalker AT boofoo DOT Eng DOT Sun DOT COM>
Date: Thu, 1 Oct 1998 02:44:59 +0000
MIME-Version: 1.0
Subject: Re: question about libm
Reply-to: mert0407 AT sable DOT ox DOT ac DOT uk
CC: djgpp AT delorie DOT com
X-mailer: Pegasus Mail for Win32 (v2.42a)

On 30 Sep 98 at 14:46, Bradley Walker wrote:

> When I use the libm.a that is included with djgcc, is this a software
> implementation of the the transcendental functions or is there any inlining
> to take advantage of a math coprocessor?

It uses the coprocessor, as does all floating point code 
compiled with gcc.  The software emulation is done by a DXE 
(emu387.dxe) and IIRC some trapping of exceptions generated 
when you try to do FP operations with no FPU.

libm.a contains more advanced and more accurate maths functions 
than those which are already present in libc.a (which in case 
you didn't know is normally linked into all your programs).

I may have misunderstood your question though; I don't know 
what you mean by mentioning "transcendental".  Transcendental 
numbers cannot be stored using floating point.

-- 
george DOT foot AT merton DOT oxford DOT ac DOT uk

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