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

[David Gibson <david@gibson.dropbear.id.au>]

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On Wed, Jul 04, 2018 at 09:42:16AM -0400, Programmingkid wrote:
> 
> > On Jul 3, 2018, at 11:31 PM, David Gibson <david@gibson.dropbear.id.au> 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?

See https://github.com/dgibson/qemu/tree/ppc-for-3.1

Same repo as my existing ppc-for-3.0 tree, different branch.

And yes, patches should be based on this tree, unless they're
important bugfixes that are aimed at 3.0.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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