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From: Richard Henderson <rth@twiddle.net>
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Date: Mon, 31 Aug 2015 22:43:17 -0700
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Subject: Re: [Qemu-devel] [PATCH v14 27/33] target-tilegx: Handle mask
 instructions
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: "walt@tilera.com" <walt@tilera.com>, Chris Metcalf <cmetcalf@ezchip.com>, QEMU Developers <qemu-devel@nongnu.org>, Chen Gang <xili_gchen_5257@hotmail.com>

On 08/30/2015 06:52 AM, Peter Maydell wrote:
> I *think* this code is correct, but the ISA manual perplexes me
> entirely. Why on earth would you describe anything as "compute
> the boolean AND of something with a value of all ones", when that's
> just a no-op? I can't see what I'm missing that means they
> didn't just describe 'mz' as "dest = srcA ? srcB : 0".

Clearly someone who decided that was the best way to implement a conditional 
move in hardware.  The language just propagated back to the manual.


r~