[clang] [llvm] [AMDGPU] Make cluster a target feature (PR #162040)

[Matt Arsenault via cfe-commits]

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@@ -1837,7 +1839,7 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
   }
 
   /// \returns true if the subtarget supports clusters of workgroups.
-  bool hasClusters() const { return GFX1250Insts; }
+  bool hasClusters() const { return HasCluster; }
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arsenm wrote:

These should have generated names from tablegen, we just didn't define the macro for it and ended up reinventing all of these getters 

https://github.com/llvm/llvm-project/pull/162040