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From: tbray@mprvaxa.UUCP (Tim Bray)
Newsgroups: net.unix-wizards
Subject: movc3 is NOT always faster!
Message-ID: <490@mprvaxa.UUCP>
Date: Tue, 13-Mar-84 12:04:30 EST
Article-I.D.: mprvaxa.490
Posted: Tue Mar 13 12:04:30 1984
Date-Received: Thu, 15-Mar-84 00:29:50 EST
References: <17425@sri-arpa.UUCP>
Organization: Microtel Pacific Research, Burnaby BC
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x <-- USENET insecticide

When you gaily issue a movc3, there's a LOT of microcode that
starts swishing around, and also if you're assembler hacking,
you might have to push all the registers that movc* steps on.

An internal DEC benchmark I saw once suggested that movc3 becomes
a win at about 100 bytes - fewer bytes than that and a tight
mov, aobleq loop is better.

Tim Bray ...decvax!microsoft!ubc-vision!mprvaxa!tbray
         ...ihnp4!alberta!ubc-vision!mprvaxa!tbray