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