Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!purdue!ames!oliveb!apple!landon
From: landon@Apple.COM (Landon Dyer)
Newsgroups: comp.sys.atari.st
Subject: Re: assemblers
Message-ID: <30327@apple.Apple.COM>
Date: 9 May 89 02:49:05 GMT
Organization: Apple Computer Inc., Cupertino, CA
Lines: 23


In article <1480@atari.UUCP> apratt@atari.UUCP (Allan Pratt) writes:
>Lastly, AS68 makes at least one illegal optimization.  Assuming that a
>missing size modifier means the same as .w, the optimization
>
>	move #1,d0	-->	moveq.l #1,d0
>
>which AS68 does is illegal.  MadMac does moveq, addq, and subq
>optimization correctly.

Not true (unless you've fixed it recently, Allan).  Take a look at the Bios
and XBios macros in "atari.s" -- they have some pretty icky conditional
assembly to optimize an ADD #n,SP to an ADDQ #n,SP.  Mistakes Were Made.

But [get closer to the campfire, kids -- this is scary] AS68 "optimizes"
MOVE.W #0,D0 (note the explicit .W) to MOVEQ #0,D0.  WUPS!  Erring on the
side of caution is not always a bad thing...

--
Landon Dyer, Apple Computer, Inc.
Development Systems Group (MPW)
Everything I said here is utter nonsense.		Give a little bit.