[clang] [Clang][OpenCL] Mark scalar loads from constant address space invariant (PR #218356)

[Keshav Vinayak Jha via cfe-commits]

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@@ -1085,6 +1085,14 @@ class CodeGenModule : public CodeGenTypeCache {
   /// space, target-specific global or constant address space may be returned.
   LangAS GetGlobalVarAddressSpace(const VarDecl *D);
 
+  /// Return whether loads from an address space are invariant.
+  bool isInvariantAddressSpace(LangAS AS) const {
+    return AS == LangAS::opencl_constant || AS == LangAS::cuda_constant;
+  }
+
+  /// Return whether loads from a global variable are invariant.
+  bool isGlobalVarInvariant(const VarDecl *D);
+
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keshavvinayak01 wrote:

@arsenm `isGlobalVarInvariant` keeps address-space recovery and classification out of the CodeGen call site.

https://github.com/llvm/llvm-project/pull/218356