From:	"Andrew Crabtree" <andrewc AT rosemail DOT rose DOT hp DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: DJGPP division optimisations
Date:	Mon, 13 Jul 1998 16:17:42 -0700
Organization:	Hewlett-Packard, Roseville
Lines:	13
Message-ID:	<6oe4in$1m7$1@rosenews.rose.hp.com>
References:	<35AA8994 DOT 3FC1 AT virgin DOT net>
NNTP-Posting-Host:	ros51675cra.rose.hp.com
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

>on long integers. In the source code I used x /= 2; y /=2; for clarity,
>on the assumption that the compiler would replace these operations with
>shifts.However, it seems this isn't a valid assumption. Replacing the code
with
>x >>= 1; y >>= 1; made a large speed up.

Just a guess, but maybe GCC only does that optimization on unisignd
integers, not signed integers.

Andy

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