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From: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
In-Reply-To: <ec117ce3-81f6-c719-73bf-f65602183c56@twiddle.net>
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Date: Mon, 25 Jul 2016 22:01:26 +0530
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Message-Id: <8760rt7k81.fsf@abhimanyu.i-did-not-set--mail-host-address--so-tickle-me>
Subject: Re: [Qemu-devel] [RFC v2 05/13] target-ppc: add modulo word
 operations
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To: Richard Henderson <rth@twiddle.net>, qemu-ppc@nongnu.org, david@gibson.dropbear.id.au
Cc: qemu-devel@nongnu.org, bharata@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com

Richard Henderson <rth@twiddle.net> writes:
> On 07/23/2016 02:14 PM, Nikunj A Dadhania wrote:
[...]
> Basically, we check for the offending cases and modify the divisor prior to the 
> division.  For unsigned:
>
> 	a / (b == 0 ? 1 : b)
>
> For signed:
>
> 	a / ((a == INT_MAX & b == -1) | (b == 0) ? : b)

So when we change the divisor to 1, undefined result is set as "a". Hope
that should be fine and doesnt break anything :-)

Regards,
Nikunj