[clang] [llvm] [HLSL] Add support for user semantics (PR #153424)

[Steven Perron via llvm-commits]

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@@ -562,6 +572,69 @@ static llvm::Value *createSPIRVBuiltinLoad(IRBuilder<> &B, llvm::Module &M,
   return B.CreateLoad(Ty, GV);
 }
 
+static llvm::Value *createSPIRVLocationLoad(IRBuilder<> &B, llvm::Module &M,
+                                            llvm::Type *Ty, unsigned Location,
+                                            StringRef Name = "") {
+  auto *GV = new llvm::GlobalVariable(
+      M, Ty, /* isConstant= */ true, llvm::GlobalValue::ExternalLinkage,
+      /* Initializer= */ nullptr, /* Name= */ Name, /* insertBefore= */ nullptr,
+      llvm::GlobalVariable::GeneralDynamicTLSModel,
+      /* AddressSpace */ 7, /* isExternallyInitialized= */ true);
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s-perron wrote:

Should we be trying to find an existing global variable? This assumes that can be just one load, which may be true for now, but I'm not sure it will always be true.

https://github.com/llvm/llvm-project/pull/153424