[llvm-dev] EuroLLVM Numerics issues

[David Greene via llvm-dev]

"Kaylor, Andrew via llvm-dev" <llvm-dev at lists.llvm.org> writes:

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> Masked vector FP operations
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> We’ve resisted adding explicitly predicated operations other than load
> and store in the past, but I think for vector FP operations we’re
> going to need this in order to maintain strict FP semantics.

Yep, we definitely will.  This is one of the reasons Simon Moll's
predication work (D57504) is so important.

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> Complex types
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> There, I said it.

I'll echo my colleague's response.

Oh hell yes!  OH HELL YES!  :)

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> Accuracy controls
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> We have a fast math flag that lets us substitute approximations for
> some math library functions. It would be nice to have a mechanism to
> control the accuracy of the approximations.

Indeed.  "Fast or not" is too coarse.

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> Per function controls
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> Similarly, it would be nice to explicitly list which math library functions could be replaced.

> I’d also like to suggest the formation of a floating point working
> group to try to get more organized about driving some of these things
> (particularly the constrained intrinsics) toward completion.

That's a great idea.

                         -David