[clang] [llvm] [DirectX] Add DirectXTargetCodeGenInfo (PR #104856)

[Justin Bogner via llvm-commits]

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@@ -0,0 +1,52 @@
+//===- DirectX.cpp---------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "ABIInfoImpl.h"
+#include "TargetInfo.h"
+#include "llvm/IR/DerivedTypes.h"
+
+using namespace clang;
+using namespace clang::CodeGen;
+
+//===----------------------------------------------------------------------===//
+// Target codegen info implementation for DirectX.
+//===----------------------------------------------------------------------===//
+
+namespace {
+
+class DirectXTargetCodeGenInfo : public TargetCodeGenInfo {
+public:
+  DirectXTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
+      : TargetCodeGenInfo(std::make_unique<DefaultABIInfo>(CGT)) {}
+
+  llvm::Type *getHLSLType(CodeGenModule &CGM, const Type *T) const override;
+};
+
+llvm::Type *DirectXTargetCodeGenInfo::getHLSLType(CodeGenModule &CGM,
+                                                  const Type *Ty) const {
+  auto *BuiltinTy = dyn_cast<BuiltinType>(Ty);
+  if (!BuiltinTy || BuiltinTy->getKind() != BuiltinType::HLSLResource)
+    return nullptr;
+
+  llvm::LLVMContext &Ctx = CGM.getLLVMContext();
+  // FIXME: translate __hlsl_resource_t to target("dx.TypedBuffer", <4 x float>,
+  // 1, 0, 1) only for now (RWBuffer<float4>); more work us needed to determine
+  // the target ext type and its parameters based on the handle type
+  // attributes (not yet implemented)
+  llvm::FixedVectorType *ElemType =
+      llvm::FixedVectorType::get(llvm::Type::getFloatTy(Ctx), 4);
+  unsigned Flags[] = {/*IsWriteable*/ 1, /*IsROV*/ 0, /*IsSigned*/ 1};
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bogner wrote:

`IsSigned` is ignored for floats, but we should probably set it to zero rather than one to avoid confusion.

https://github.com/llvm/llvm-project/pull/104856