[PATCH] D139481: NVPTX: Cleanup check for denormal mode

[Artem Belevich via Phabricator via llvm-commits]

tra added inline comments.


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Comment at: llvm/lib/Target/NVPTX/NVPTXTargetTransformInfo.cpp:149-151
     // Denormal handling is guarded by different attributes depending on the
     // type (denormal-fp-math vs denormal-fp-math-f32), take note of halfs.
     bool IsHalfTy = false;
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Huh. I wonder why are we using isHalfTy for figuring out denormal mode.

Considering that it seems to be FP32 that is the special case with an attribute of its own, it should've been `IsSingleTy`. Knowing whether it's fp16 or not only allows us to get correct mode for fp16, but not for the other types.


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Comment at: llvm/lib/Target/NVPTX/NVPTXTargetTransformInfo.cpp:374
+        Action.IsHalfTy ? APFloat::IEEEhalf() : APFloat::IEEEsingle());
+    bool FtzEnabled = Mode.Output == DenormalMode::PreserveSign;
 
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arsenm wrote:
> Looks broken for double to me but I don't know what the options are

Indeed. I do not understand why getDenormalMode appears to single out fp32 as a special case.




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  https://reviews.llvm.org/D139481/new/

https://reviews.llvm.org/D139481