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From: Tom Musta <tommusta@gmail.com>
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Subject: Re: [Qemu-devel] [PATCH 12/14] VSX Stage 4: Add Scalar SP Fused
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To: Richard Henderson <rth@twiddle.net>, qemu-devel@nongnu.org
Cc: qemu-ppc@nongnu.org

On 11/13/2013 5:14 PM, Richard Henderson wrote:
> On 11/14/2013 06:49 AM, Tom Musta wrote:
>> I have also done quite a bit of random and targeted random testing using Power
>> hardware to produce expected results.  The targeted random tests followed your
>> suggestion above: generate AxB + C where abs(exp(A) - exp(B)) = 23 and
>> abs(exp(A) - exp(C)) = 46.  Several million test patterns have been generated
>> and played back through QEMU without any miscompares in the numerical results.
> 
> Here's an example that produces wrong results when rounding to double first.
> Replace the portable math.h calls with ppc asm as necessary.
> 
> <snip>
> r~
> 

Thanks, Richard.  You have convinced me.