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Re: [Qemu-ppc] [PATCH for-3.1 0/7] target/ppc fp cleanups

From: Programmingkid
Subject: Re: [Qemu-ppc] [PATCH for-3.1 0/7] target/ppc fp cleanups
Date: Wed, 4 Jul 2018 09:42:16 -0400

> On Jul 3, 2018, at 11:31 PM, David Gibson <address@hidden> wrote:
> On Tue, Jul 03, 2018 at 08:17:25AM -0700, Richard Henderson wrote:
>> Beginning with John Arbuckle's fdiv test case, clean up some
>> of the fp helpers.  As with fdiv, fre and fresqrt are missing
>> divide-by-zero exceptions.
>> I've also noticed that load/store were using arithmetic conversions
>> to/from float32.  These should be using the non-arithmetic algorithms
>> listed in the manual.
>> Aside from cleaning up all of the rest of the helpers, I believe that
>> the implementation of the single-precision operations are incorrect.
>> They are currently implemented with the double-precision operation
>> followed by a round-to-single.  This causes incorrect results via
>> double rounding.  I believe better results could be had by using
>> these non-arithmetic converters to produce float32 operands, use the
>> proper float32 softfloat operations, and then convert back.
>> Anyway, all of this has been broken long enough that it'll need to
>> wait til next devel cycle before anything further gets done.
> Applied to ppc-for-3.1 (newly created)

Could I have the address for your ppc-for-3.1 repo please? Would you like 
future floating point patches to be based on this repo?

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