1 //===--- CodeGenTypes.h - Type translation for LLVM CodeGen -----*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This is the code that handles AST -> LLVM type lowering. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef CLANG_CODEGEN_CODEGENTYPES_H 15 #define CLANG_CODEGEN_CODEGENTYPES_H 16 17 #include "CGCall.h" 18 #include "clang/AST/GlobalDecl.h" 19 #include "clang/CodeGen/CGFunctionInfo.h" 20 #include "llvm/ADT/DenseMap.h" 21 #include "llvm/IR/Module.h" 22 #include <vector> 23 24 namespace llvm { 25 class FunctionType; 26 class Module; 27 class DataLayout; 28 class Type; 29 class LLVMContext; 30 class StructType; 31 } 32 33 namespace clang { 34 class ABIInfo; 35 class ASTContext; 36 template <typename> class CanQual; 37 class CXXConstructorDecl; 38 class CXXDestructorDecl; 39 class CXXMethodDecl; 40 class CodeGenOptions; 41 class FieldDecl; 42 class FunctionProtoType; 43 class ObjCInterfaceDecl; 44 class ObjCIvarDecl; 45 class PointerType; 46 class QualType; 47 class RecordDecl; 48 class TagDecl; 49 class TargetInfo; 50 class Type; 51 typedef CanQual<Type> CanQualType; 52 53 namespace CodeGen { 54 class CGCXXABI; 55 class CGRecordLayout; 56 class CodeGenModule; 57 class RequiredArgs; 58 59 /// CodeGenTypes - This class organizes the cross-module state that is used 60 /// while lowering AST types to LLVM types. 61 class CodeGenTypes { 62 CodeGenModule &CGM; 63 // Some of this stuff should probably be left on the CGM. 64 ASTContext &Context; 65 llvm::Module &TheModule; 66 const llvm::DataLayout &TheDataLayout; 67 const TargetInfo &Target; 68 CGCXXABI &TheCXXABI; 69 70 // This should not be moved earlier, since its initialization depends on some 71 // of the previous reference members being already initialized 72 const ABIInfo &TheABIInfo; 73 74 /// The opaque type map for Objective-C interfaces. All direct 75 /// manipulation is done by the runtime interfaces, which are 76 /// responsible for coercing to the appropriate type; these opaque 77 /// types are never refined. 78 llvm::DenseMap<const ObjCInterfaceType*, llvm::Type *> InterfaceTypes; 79 80 /// CGRecordLayouts - This maps llvm struct type with corresponding 81 /// record layout info. 82 llvm::DenseMap<const Type*, CGRecordLayout *> CGRecordLayouts; 83 84 /// RecordDeclTypes - This contains the LLVM IR type for any converted 85 /// RecordDecl. 86 llvm::DenseMap<const Type*, llvm::StructType *> RecordDeclTypes; 87 88 /// FunctionInfos - Hold memoized CGFunctionInfo results. 89 llvm::FoldingSet<CGFunctionInfo> FunctionInfos; 90 91 /// RecordsBeingLaidOut - This set keeps track of records that we're currently 92 /// converting to an IR type. For example, when converting: 93 /// struct A { struct B { int x; } } when processing 'x', the 'A' and 'B' 94 /// types will be in this set. 95 llvm::SmallPtrSet<const Type*, 4> RecordsBeingLaidOut; 96 97 llvm::SmallPtrSet<const CGFunctionInfo*, 4> FunctionsBeingProcessed; 98 99 /// SkippedLayout - True if we didn't layout a function due to a being inside 100 /// a recursive struct conversion, set this to true. 101 bool SkippedLayout; 102 103 SmallVector<const RecordDecl *, 8> DeferredRecords; 104 105 private: 106 /// TypeCache - This map keeps cache of llvm::Types 107 /// and maps clang::Type to corresponding llvm::Type. 108 llvm::DenseMap<const Type *, llvm::Type *> TypeCache; 109 110 public: 111 CodeGenTypes(CodeGenModule &cgm); 112 ~CodeGenTypes(); 113 114 const llvm::DataLayout &getDataLayout() const { return TheDataLayout; } 115 ASTContext &getContext() const { return Context; } 116 const ABIInfo &getABIInfo() const { return TheABIInfo; } 117 const TargetInfo &getTarget() const { return Target; } 118 CGCXXABI &getCXXABI() const { return TheCXXABI; } 119 llvm::LLVMContext &getLLVMContext() { return TheModule.getContext(); } 120 121 /// ConvertType - Convert type T into a llvm::Type. 122 llvm::Type *ConvertType(QualType T); 123 124 /// ConvertTypeForMem - Convert type T into a llvm::Type. This differs from 125 /// ConvertType in that it is used to convert to the memory representation for 126 /// a type. For example, the scalar representation for _Bool is i1, but the 127 /// memory representation is usually i8 or i32, depending on the target. 128 llvm::Type *ConvertTypeForMem(QualType T); 129 130 /// GetFunctionType - Get the LLVM function type for \arg Info. 131 llvm::FunctionType *GetFunctionType(const CGFunctionInfo &Info); 132 133 llvm::FunctionType *GetFunctionType(GlobalDecl GD); 134 135 /// isFuncTypeConvertible - Utility to check whether a function type can 136 /// be converted to an LLVM type (i.e. doesn't depend on an incomplete tag 137 /// type). 138 bool isFuncTypeConvertible(const FunctionType *FT); 139 bool isFuncParamTypeConvertible(QualType Ty); 140 141 /// GetFunctionTypeForVTable - Get the LLVM function type for use in a vtable, 142 /// given a CXXMethodDecl. If the method to has an incomplete return type, 143 /// and/or incomplete argument types, this will return the opaque type. 144 llvm::Type *GetFunctionTypeForVTable(GlobalDecl GD); 145 146 const CGRecordLayout &getCGRecordLayout(const RecordDecl*); 147 148 /// UpdateCompletedType - When we find the full definition for a TagDecl, 149 /// replace the 'opaque' type we previously made for it if applicable. 150 void UpdateCompletedType(const TagDecl *TD); 151 152 /// getNullaryFunctionInfo - Get the function info for a void() 153 /// function with standard CC. 154 const CGFunctionInfo &arrangeNullaryFunction(); 155 156 // The arrangement methods are split into three families: 157 // - those meant to drive the signature and prologue/epilogue 158 // of a function declaration or definition, 159 // - those meant for the computation of the LLVM type for an abstract 160 // appearance of a function, and 161 // - those meant for performing the IR-generation of a call. 162 // They differ mainly in how they deal with optional (i.e. variadic) 163 // arguments, as well as unprototyped functions. 164 // 165 // Key points: 166 // - The CGFunctionInfo for emitting a specific call site must include 167 // entries for the optional arguments. 168 // - The function type used at the call site must reflect the formal 169 // signature of the declaration being called, or else the call will 170 // go awry. 171 // - For the most part, unprototyped functions are called by casting to 172 // a formal signature inferred from the specific argument types used 173 // at the call-site. However, some targets (e.g. x86-64) screw with 174 // this for compatibility reasons. 175 176 const CGFunctionInfo &arrangeGlobalDeclaration(GlobalDecl GD); 177 const CGFunctionInfo &arrangeFunctionDeclaration(const FunctionDecl *FD); 178 const CGFunctionInfo & 179 arrangeFreeFunctionDeclaration(QualType ResTy, const FunctionArgList &Args, 180 const FunctionType::ExtInfo &Info, 181 bool isVariadic); 182 183 const CGFunctionInfo &arrangeObjCMethodDeclaration(const ObjCMethodDecl *MD); 184 const CGFunctionInfo &arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD, 185 QualType receiverType); 186 187 const CGFunctionInfo &arrangeCXXMethodDeclaration(const CXXMethodDecl *MD); 188 const CGFunctionInfo &arrangeCXXConstructorDeclaration( 189 const CXXConstructorDecl *D, 190 CXXCtorType Type); 191 const CGFunctionInfo &arrangeCXXConstructorCall(const CallArgList &Args, 192 const CXXConstructorDecl *D, 193 CXXCtorType CtorKind, 194 unsigned ExtraArgs); 195 const CGFunctionInfo &arrangeCXXDestructor(const CXXDestructorDecl *D, 196 CXXDtorType Type); 197 198 const CGFunctionInfo &arrangeFreeFunctionCall(const CallArgList &Args, 199 const FunctionType *Ty); 200 const CGFunctionInfo &arrangeFreeFunctionCall(QualType ResTy, 201 const CallArgList &args, 202 FunctionType::ExtInfo info, 203 RequiredArgs required); 204 const CGFunctionInfo &arrangeBlockFunctionCall(const CallArgList &args, 205 const FunctionType *type); 206 207 const CGFunctionInfo &arrangeCXXMethodCall(const CallArgList &args, 208 const FunctionProtoType *type, 209 RequiredArgs required); 210 211 const CGFunctionInfo &arrangeFreeFunctionType(CanQual<FunctionProtoType> Ty); 212 const CGFunctionInfo &arrangeFreeFunctionType(CanQual<FunctionNoProtoType> Ty); 213 const CGFunctionInfo &arrangeCXXMethodType(const CXXRecordDecl *RD, 214 const FunctionProtoType *FTP); 215 216 /// "Arrange" the LLVM information for a call or type with the given 217 /// signature. This is largely an internal method; other clients 218 /// should use one of the above routines, which ultimately defer to 219 /// this. 220 /// 221 /// \param argTypes - must all actually be canonical as params 222 const CGFunctionInfo &arrangeLLVMFunctionInfo(CanQualType returnType, 223 bool IsInstanceMethod, 224 ArrayRef<CanQualType> argTypes, 225 FunctionType::ExtInfo info, 226 RequiredArgs args); 227 228 /// \brief Compute a new LLVM record layout object for the given record. 229 CGRecordLayout *ComputeRecordLayout(const RecordDecl *D, 230 llvm::StructType *Ty); 231 232 /// addRecordTypeName - Compute a name from the given record decl with an 233 /// optional suffix and name the given LLVM type using it. 234 void addRecordTypeName(const RecordDecl *RD, llvm::StructType *Ty, 235 StringRef suffix); 236 237 238 public: // These are internal details of CGT that shouldn't be used externally. 239 /// ConvertRecordDeclType - Lay out a tagged decl type like struct or union. 240 llvm::StructType *ConvertRecordDeclType(const RecordDecl *TD); 241 242 /// GetExpandedTypes - Expand the type \arg Ty into the LLVM 243 /// argument types it would be passed as on the provided vector \arg 244 /// ArgTys. See ABIArgInfo::Expand. 245 void GetExpandedTypes(QualType type, 246 SmallVectorImpl<llvm::Type*> &expanded); 247 248 /// IsZeroInitializable - Return whether a type can be 249 /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer. 250 bool isZeroInitializable(QualType T); 251 252 /// IsZeroInitializable - Return whether a record type can be 253 /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer. 254 bool isZeroInitializable(const CXXRecordDecl *RD); 255 256 bool isRecordLayoutComplete(const Type *Ty) const; 257 bool noRecordsBeingLaidOut() const { 258 return RecordsBeingLaidOut.empty(); 259 } 260 bool isRecordBeingLaidOut(const Type *Ty) const { 261 return RecordsBeingLaidOut.count(Ty); 262 } 263 264 }; 265 266 } // end namespace CodeGen 267 } // end namespace clang 268 269 #endif 270
