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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] qemu-arm: wrong execution of post-indexed loads when
	Rm and Rd are the same register
Date: Thu, 15 Mar 2007 20:03:20 +0000
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To: qemu-devel@nongnu.org
Cc: Lauro Ramos Venancio <lauro.venancio@indt.org.br>

On Thursday 15 March 2007 19:35, Lauro Ramos Venancio wrote:
> Qemu-arm is wrongly executing post-indexed loads when Rm and Rd are
> the same register. For example:
>
> ldr r0, [r1], +r0
>
> Current behavior:
> r0 <- [r1]
> r1 <- r1 + r0
>
> Expected behavior:
> addr <- r1
> r1 <- r1 + r0
> r0 <- [addr]

This is still wrong. The writeback must happen after the load. Your 
implementation will give incorrect results if the load faults.

Paul