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

[Johannes Doerfert via llvm-commits]

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

AAUniform will determine/propagate uniformity itself at some point (see the other comment). So it actually derives uniformity, and manifests it for arguments with inreg. As you derive uniformity, other positions will require different manifestations. Still, the base property here is uniformity. 

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