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Subject: Re: [Qemu-devel] [PATCH 05/18] target-ppc: Add ISA 2.06 divwe[u][o]
 Instructions
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To: Tom Musta <tommusta@gmail.com>, qemu-devel@nongnu.org
Cc: qemu-ppc@nongnu.org

On 12/10/2013 09:58 AM, Tom Musta wrote:
>> > The second test can never be true, since ra has 32 zero bits.
>> > Thus the first test is also pointless.
> Hmm.  Consider the case where GPR[RA] = 0xUUUUUUUU_80000000 (U=don't care) and
> GPR[RB] = 0xUUUUUUUU_FFFFFFFF.  Without these checks, I do not believe overflow
> will be properly detected.
> 

Hmm.  I'm not sure what I was thinking here.  Ignore all that.


r~