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Message-ID: <4319E40B.F2219D3@dessent.net>
Date: Sat, 03 Sep 2005 10:57:31 -0700
From: Brian Dessent <brian AT dessent DOT net>
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To: cygwin AT cygwin DOT com
Subject: Re: [patch] lrint/lrintf oddity
References: <20050903185145 DOT 5bb6c57e DOT cygwin-erikd AT mega-nerd DOT com> 	<4319C016 DOT 2958BC77 AT dessent DOT net> <20050904023143 DOT 48fed0c5 DOT cygwin-erikd AT mega-nerd DOT com>
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Erik de Castro Lopo wrote:

> Err, what??????????????
> 
> On Linux, the lrintf() function is an inline function that reduces to
> a single asm instruction.

Linux uses glibc, Cygwin uses newlib.  They're not the same thing. 
Glibc is highly optimized and tweaked, newlib is designed as a small and
portable libc for embedded systems.  It does not have inline versions of
these functions.

> I'm using lrintf() to convert huge arrays of floats to ints. I'd like
> that to be reasonably quick :-). Any chance of replacing all that code
> you've got with a single inline asm instruction like Linux has?

<http://cygwin.com/acronyms/#PTC>.  The newlib mailing list is right
over there -->

Be aware that newlib supports a wide variety of platforms, some with no
FPU, so you can't just go yanking stuff out.

If you don't care about portability you could probably #define the
inline asm versions of the functions.

Brian

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