[PATCH] D67981: [NFC][PowerPC] Adding FeatureFPU in the definition of FeatureISA3_0

Fri Sep 27 14:08:36 PDT 2019

jsji added inline comments.

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Comment at: llvm/lib/Target/PowerPC/PPC.td:193
+                                     "Enable instructions added in ISA 3.0.",
+                                     [FeatureFPU]>;
 def FeatureP9Altivec : SubtargetFeature<"power9-altivec", "HasP9Altivec", "true",
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Looks like there is some misunderstanding of what `FeatureISA3_0` is for?

As in the description, `FeatureISA3_0` is for new instruction added in ISA 3.0, not all the instructions in ISA 3.0.
Why it need to depend on FeatureFPU?

In other words, with the new patch `-mattr=-fpu` will also remove `isa-v30-instructions` effectively.
So that means, if you add -mattr=-fpu, you can't use any of the new instruction added for P8? 
Is that what you intended?

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D67981/new/

https://reviews.llvm.org/D67981