From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <985de6bd0d7ab132a2c3708e4d8d3963@plan9.bell-labs.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] how to avoid a memset() optimization
From: "Russ Cox" <rsc@plan9.bell-labs.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Date: Thu, 14 Nov 2002 12:28:10 -0500
Topicbox-Message-UUID: 200f7794-eacb-11e9-9e20-41e7f4b1d025

> Do you really want the compiler to always generate code
> 	MOV	R1,#0
> 	MOV	R2,#0
> 	AND	R2,R1
> 	MOV	R2,X(SP)
> ?  Almost any modern compiler will peform the AND at
> compiler time (constant folding), and most customers want
> that.  Anyway, I don't see why you need to AND in this
> context.  Are you talking about the C and V bits?  If some
> other process can inspect those for your process I'd think
> it could inspect a whole lot more..

i _said_ it was a stupid argument.  my point was more
that volatile addresses memory optimizations but not
necessarily other things which might matter just as much.