[clang] [llvm] [WIP] ABI Lowering Library (PR #140112)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,76 @@
+//===---- ABITypeMapper.h - Maps LLVM ABI Types to LLVM IR Types --------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Maps LLVM ABI type representations back to corresponding LLVM IR types.
+/// This reverse mapper translates low-level ABI-specific types back into
+/// LLVM IR types suitable for code generation and optimization passes.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_ABITYPEMAPPER_H
+#define LLVM_CODEGEN_ABITYPEMAPPER_H
+
+#include "llvm/ABI/Types.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Type.h"
+#include "llvm/Support/TypeSize.h"
+
+namespace llvm {
+
+class ABITypeMapper {
+public:
+  explicit ABITypeMapper(LLVMContext &Ctx, const DataLayout &DataLayout)
+      : Context(Ctx), DL(DataLayout) {}
+
+  Type *convertType(const abi::Type *ABIType);
+
+  void clearCache() { TypeCache.clear(); }
+
+private:
+  LLVMContext &Context;
+  const DataLayout &DL;
+
+  DenseMap<const abi::Type *, Type *> TypeCache;
+
+  Type *convertIntegerType(const abi::IntegerType *IT);
+
+  Type *convertFieldType(const abi::Type *FieldType);
+
+  Type *convertFloatType(const abi::FloatType *FT);
+
+  Type *convertPointerType(const abi::PointerType *PT);
+
+  Type *convertArrayType(const abi::ArrayType *AT);
+
+  Type *convertMatrixType(const abi::ArrayType *MT);
+
+  Type *convertVectorType(const abi::VectorType *VT);
+
+  Type *convertStructType(const abi::StructType *ST);
+
+  Type *convertVoidType(const abi::VoidType *VT);
+
+  Type *getFloatTypeForSemantics(const fltSemantics &Semantics);
+
+  StructType *createStructFromFields(ArrayRef<abi::FieldInfo> Fields,
+                                     uint32_t NumFields, TypeSize Size,
----------------
nikic wrote:

Shouldn't need NumFields, implied by ArrayRef?

https://github.com/llvm/llvm-project/pull/140112