1 //===----- ABIInfo.h - ABI information access & encapsulation ---*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_CLANG_LIB_CODEGEN_ABIINFO_H 10 #define LLVM_CLANG_LIB_CODEGEN_ABIINFO_H 11 12 #include "clang/AST/CharUnits.h" 13 #include "clang/AST/Type.h" 14 #include "llvm/IR/CallingConv.h" 15 #include "llvm/IR/Type.h" 16 17 namespace llvm { 18 class Value; 19 class LLVMContext; 20 class DataLayout; 21 class Type; 22 } 23 24 namespace clang { 25 class ASTContext; 26 class CodeGenOptions; 27 class TargetInfo; 28 29 namespace CodeGen { 30 class ABIArgInfo; 31 class Address; 32 class CGCXXABI; 33 class CGFunctionInfo; 34 class CodeGenFunction; 35 class CodeGenTypes; 36 class SwiftABIInfo; 37 38 namespace swiftcall { 39 class SwiftAggLowering; 40 } 41 42 // FIXME: All of this stuff should be part of the target interface 43 // somehow. It is currently here because it is not clear how to factor 44 // the targets to support this, since the Targets currently live in a 45 // layer below types n'stuff. 46 47 48 /// ABIInfo - Target specific hooks for defining how a type should be 49 /// passed or returned from functions. 50 class ABIInfo { 51 public: 52 CodeGen::CodeGenTypes &CGT; 53 protected: 54 llvm::CallingConv::ID RuntimeCC; 55 public: 56 ABIInfo(CodeGen::CodeGenTypes &cgt) 57 : CGT(cgt), RuntimeCC(llvm::CallingConv::C) {} 58 59 virtual ~ABIInfo(); 60 61 virtual bool supportsSwift() const { return false; } 62 63 virtual bool allowBFloatArgsAndRet() const { return false; } 64 65 CodeGen::CGCXXABI &getCXXABI() const; 66 ASTContext &getContext() const; 67 llvm::LLVMContext &getVMContext() const; 68 const llvm::DataLayout &getDataLayout() const; 69 const TargetInfo &getTarget() const; 70 const CodeGenOptions &getCodeGenOpts() const; 71 72 /// Return the calling convention to use for system runtime 73 /// functions. 74 llvm::CallingConv::ID getRuntimeCC() const { 75 return RuntimeCC; 76 } 77 78 virtual void computeInfo(CodeGen::CGFunctionInfo &FI) const = 0; 79 80 /// EmitVAArg - Emit the target dependent code to load a value of 81 /// \arg Ty from the va_list pointed to by \arg VAListAddr. 82 83 // FIXME: This is a gaping layering violation if we wanted to drop 84 // the ABI information any lower than CodeGen. Of course, for 85 // VAArg handling it has to be at this level; there is no way to 86 // abstract this out. 87 virtual CodeGen::Address EmitVAArg(CodeGen::CodeGenFunction &CGF, 88 CodeGen::Address VAListAddr, 89 QualType Ty) const = 0; 90 91 bool isAndroid() const; 92 93 /// Emit the target dependent code to load a value of 94 /// \arg Ty from the \c __builtin_ms_va_list pointed to by \arg VAListAddr. 95 virtual CodeGen::Address EmitMSVAArg(CodeGen::CodeGenFunction &CGF, 96 CodeGen::Address VAListAddr, 97 QualType Ty) const; 98 99 virtual bool isHomogeneousAggregateBaseType(QualType Ty) const; 100 101 virtual bool isHomogeneousAggregateSmallEnough(const Type *Base, 102 uint64_t Members) const; 103 104 bool isHomogeneousAggregate(QualType Ty, const Type *&Base, 105 uint64_t &Members) const; 106 107 // Implement the Type::IsPromotableIntegerType for ABI specific needs. The 108 // only difference is that this considers _ExtInt as well. 109 bool isPromotableIntegerTypeForABI(QualType Ty) const; 110 111 /// A convenience method to return an indirect ABIArgInfo with an 112 /// expected alignment equal to the ABI alignment of the given type. 113 CodeGen::ABIArgInfo 114 getNaturalAlignIndirect(QualType Ty, bool ByVal = true, 115 bool Realign = false, 116 llvm::Type *Padding = nullptr) const; 117 118 CodeGen::ABIArgInfo 119 getNaturalAlignIndirectInReg(QualType Ty, bool Realign = false) const; 120 121 122 }; 123 124 /// A refining implementation of ABIInfo for targets that support swiftcall. 125 /// 126 /// If we find ourselves wanting multiple such refinements, they'll probably 127 /// be independent refinements, and we should probably find another way 128 /// to do it than simple inheritance. 129 class SwiftABIInfo : public ABIInfo { 130 public: 131 SwiftABIInfo(CodeGen::CodeGenTypes &cgt) : ABIInfo(cgt) {} 132 133 bool supportsSwift() const final override { return true; } 134 135 virtual bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> types, 136 bool asReturnValue) const = 0; 137 138 virtual bool isLegalVectorTypeForSwift(CharUnits totalSize, 139 llvm::Type *eltTy, 140 unsigned elts) const; 141 142 virtual bool isSwiftErrorInRegister() const = 0; 143 144 static bool classof(const ABIInfo *info) { 145 return info->supportsSwift(); 146 } 147 }; 148 } // end namespace CodeGen 149 } // end namespace clang 150 151 #endif 152