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Message-ID: <48583306.8090600@bellard.org>
Date: Tue, 17 Jun 2008 23:56:22 +0200
From: Fabrice Bellard <fabrice@bellard.org>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] Wanted: A better way to implement MIPS unaligned
	instructions
References: <20080617121251.GB23435@networkno.de>
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To: qemu-devel@nongnu.org

Thiemo Seufer wrote:
> Hello All,
> 
> I am currently trying to implement TCG versions of the MIPS [ls][dw][lr]
> set of instructions. I believe I can't use a helper function for
> load/store type instructions. The appended patch uses TCG directly, but
> the resulting translation is excessively complicated. Is there a better
> way to do this?

A simpler solution is to use the same code as before in an helper.
Helpers are perfectly usable in this case provided the cpu state is
saved before calling them.

When the helper solution will work, it will be possible to optimize it
by directly accessing the QEMU TLB cache to do word accesses and to
generate the correct exception.

Fabrice.