[clang] [HLSL] Implement `SpirvType` and `SpirvOpaqueType` (PR #134034)

[Chris B via cfe-commits]

================
@@ -369,14 +369,102 @@ llvm::Type *CommonSPIRTargetCodeGenInfo::getOpenCLType(CodeGenModule &CGM,
   return nullptr;
 }
 
+// Gets a spirv.IntegralConstant or spirv.Literal. If IntegralType is present,
+// returns an IntegralConstant, otherwise returns a Literal.
+static llvm::Type *getInlineSpirvConstant(CodeGenModule &CGM,
+                                          llvm::Type *IntegralType,
+                                          llvm::APInt Value) {
+  llvm::LLVMContext &Ctx = CGM.getLLVMContext();
+
+  // Convert the APInt value to an array of uint32_t words
+  llvm::SmallVector<uint32_t> Words;
+
+  while (Value.ugt(0)) {
+    uint32_t Word = Value.trunc(32).getZExtValue();
+    Value.lshrInPlace(32);
+
+    Words.push_back(Word);
+  }
+  if (Words.size() == 0)
+    Words.push_back(0);
+
+  if (IntegralType) {
+    return llvm::TargetExtType::get(Ctx, "spirv.IntegralConstant",
+                                    {IntegralType}, Words);
+  } else {
+    return llvm::TargetExtType::get(Ctx, "spirv.Literal", {}, Words);
+  }
----------------
llvm-beanz wrote:

nit: [braces](https://llvm.org/docs/CodingStandards.html#don-t-use-braces-on-simple-single-statement-bodies-of-if-else-loop-statements) & [else](https://llvm.org/docs/CodingStandards.html#don-t-use-else-after-a-return)
```suggestion
  if (IntegralType)
    return llvm::TargetExtType::get(Ctx, "spirv.IntegralConstant",
                                    {IntegralType}, Words);
  return llvm::TargetExtType::get(Ctx, "spirv.Literal", {}, Words);
```

https://github.com/llvm/llvm-project/pull/134034