[llvm] [AMDGPU][Attributor] Infer `inreg` attribute in `AMDGPUAttributor` (PR #101609)

[Sameer Sahasrabuddhe via llvm-commits]

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@@ -1014,6 +1015,100 @@ struct AAAMDGPUNoAGPR
 
 const char AAAMDGPUNoAGPR::ID = 0;
 
+struct AAAMDGPUInreg
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ssahasra wrote:

I am also in favour calling it Uniform. It's an interesting choice. The attribute itself may be called ``inreg``, but it is merely an implementation of what is actually uniformity. But then, later if we want to infer ``inreg`` for some other reason Foo, I am not sure if that should be a yet another AAFoo, or it should be unified with AAUniform under a single AAInreg.

https://github.com/llvm/llvm-project/pull/101609