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From: Richard Henderson <richard.henderson@linaro.org>
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Date: Sun, 24 Jun 2018 11:30:36 -0700
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Subject: Re: [Qemu-devel] [PATCH] fix fdiv instruction
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To: Programmingkid <programmingkidx@gmail.com>
Cc: david@gibson.dropbear.id.au, qemu-devel@nongnu.org, qemu-ppc@nongnu.org

On 06/24/2018 06:46 AM, Programmingkid wrote:
>> Even in your referenced PDF, table 3-13, it says that frD is unmodified.
> 
> Actually it says when FPSCR[ZE] is set is when frD is unmodified. When FPSCR[ZE] is not set it frD's sign is determined by an XOR of the signs of the operands. I have verified that this is what happens on real PowerPC 750 and 950 CPUs. 


Of course.  When ZE is not set, 1 / 0 -> inf (and -1 / 0 -> -inf, etc).
But ZE not set is not the topic of discussion, or the subject of your patch.


> I was just wondering are you able to run a PowerPC operating system in QEMU
> in KVM mode on this Power7 computer?

Sadly not.  KVM is not enabled in this setup.


r~