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
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>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