[PATCH] D121768: [tablgen][X86] Auto-generate fields & interfaces for target features

[Kan Shengchen via Phabricator via llvm-commits]

skan added inline comments.


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Comment at: llvm/lib/Target/X86/X86.td:22
 
-def Mode64Bit : SubtargetFeature<"64bit-mode", "In64BitMode", "true",
                                   "64-bit mode (x86_64)">;
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pengfei wrote:
> I think `In64BitMode` is more readable, we usually generate 32 bit instructions under 64 bit mode.
It's meaningless to have different name for inteface and the member. We already use the interface `is64Bit`.


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Comment at: llvm/lib/Target/X86/X86.td:33
 
 def FeatureX87     : SubtargetFeature<"x87","HasX87", "true",
                                       "Enable X87 float instructions">;
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pengfei wrote:
> How about define a new class like `TrivalSubtargetFeature` so that we don't need to add `, [], 0` to the old one?
If so, then we have to replace most of `SubtargetFeature` with `TrivalSubtargetFeature`.  Now we only need to add `, [], 0` for CMOV, so I think `TrivalSubtargetFeature` is 
not worthy.


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  https://reviews.llvm.org/D121768/new/

https://reviews.llvm.org/D121768