From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Subject: Re: [9fans] 8a/8l bug
In-Reply-To: Your message of "Wed, 17 Dec 2003 14:26:36 EST."
             <20031217192636.GA7069@ionkov.net>
From: "Russ Cox" <rsc@swtch.com>
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Date: Wed, 17 Dec 2003 17:54:19 -0500
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> Also
> 	ADDL	$-1, AX
>
> is not equivalent to
>
> 	SUBL	$1, AX
>
> The CF flag is different.

The linker is doing the "optimizations" as part of
instruction selection.  (The split of work between
compiler and loader is different than it is with gcc.)

In uchar yaddl[] = { ..., delete the two lines beginning
with Yi1.

Then you have to edit all the table entries in optab[]
that reference yaddl to remove the offending inc/dec
instructions.  But I can't remember how to decode
that table.

Russ