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

[Matt Arsenault via cfe-commits]

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@@ -2248,6 +2248,9 @@ llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
       Addr.withElementType(convertTypeForLoadStore(Ty, Addr.getElementType()));
 
   llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
+  if (Ty.getAddressSpace() == LangAS::opencl_constant)
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arsenm wrote:

There probably should be a more general check function for this. This would also apply to Cuda __constant__ 

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