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Subject: Re: [Qemu-devel] [PATCH 15/19] Add VSX xmax/xmin Instructions
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To: Tom Musta <tommusta@gmail.com>, QEMU Developers <qemu-devel@nongnu.org>
Cc: "qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>

On 10/24/2013 09:26 AM, Tom Musta wrote:
> Because of the Power ISA definitions of maximum and minimum
> on various boundary cases, the standard softfloat comparison
> routines (e.g. float64_lt) do not work as well as one might
> think.  Therefore specific routines for comparing 64 and 32
> bit floating point numbers are implemented in the PowerPC
> helper code.

Really?  All I see in the document is ">fp", used both here
in the minmax insn and in the cmp insn.

If the softfloat compare isn't good enough for minmax, how
can it be good enough for cmp?


r~