//===--- CGDebugInfo.cpp - Emit Debug Information for a Module ------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This coordinates the debug information generation while generating code. // //===----------------------------------------------------------------------===// #include "CGDebugInfo.h" #include "CodeGenModule.h" #include "clang/AST/ASTContext.h" #include "clang/AST/Decl.h" #include "clang/AST/Expr.h" #include "clang/AST/RecordLayout.h" #include "clang/Basic/SourceManager.h" #include "clang/Basic/FileManager.h" #include "llvm/Constants.h" #include "llvm/DerivedTypes.h" #include "llvm/Instructions.h" #include "llvm/Intrinsics.h" #include "llvm/Module.h" #include "llvm/ADT/StringExtras.h" #include "llvm/ADT/SmallVector.h" #include "llvm/Support/Dwarf.h" #include "llvm/Target/TargetMachine.h" using namespace clang; using namespace clang::CodeGen; CGDebugInfo::CGDebugInfo(CodeGenModule *m) : M(m), DebugFactory(M->getModule()) { } CGDebugInfo::~CGDebugInfo() { assert(RegionStack.empty() && "Region stack mismatch, stack not empty!"); } void CGDebugInfo::setLocation(SourceLocation Loc) { if (Loc.isValid()) CurLoc = M->getContext().getSourceManager().getInstantiationLoc(Loc); } /// getOrCreateCompileUnit - Get the compile unit from the cache or create a new /// one if necessary. This returns null for invalid source locations. llvm::DICompileUnit CGDebugInfo::getOrCreateCompileUnit(SourceLocation Loc) { // FIXME: Until we do a complete job of emitting debug information, // we need to support making dummy compile units so that we generate // "well formed" debug info. const FileEntry *FE = 0; if (Loc.isValid()) { SourceManager &SM = M->getContext().getSourceManager(); Loc = SM.getInstantiationLoc(Loc); FE = SM.getFileEntryForID(SM.getFileID(Loc)); } // See if this compile unit has been used before. llvm::DICompileUnit &Unit = CompileUnitCache[FE]; if (!Unit.isNull()) return Unit; // Get source file information. const char *FileName = FE ? FE->getName() : ""; const char *DirName = FE ? FE->getDir()->getName() : ""; // Create new compile unit. // FIXME: Handle other language IDs as well. // FIXME: Do not know how to get clang version yet. return Unit = DebugFactory.CreateCompileUnit(llvm::dwarf::DW_LANG_C89, FileName, DirName, "clang"); } /// getOrCreateBuiltinType - Get the Basic type from the cache or create a new /// one if necessary. llvm::DIType CGDebugInfo::CreateType(const BuiltinType *BT, llvm::DICompileUnit Unit){ unsigned Encoding = 0; switch (BT->getKind()) { default: case BuiltinType::Void: return llvm::DIType(); case BuiltinType::UChar: case BuiltinType::Char_U: Encoding = llvm::dwarf::DW_ATE_unsigned_char; break; case BuiltinType::Char_S: case BuiltinType::SChar: Encoding = llvm::dwarf::DW_ATE_signed_char; break; case BuiltinType::UShort: case BuiltinType::UInt: case BuiltinType::ULong: case BuiltinType::ULongLong: Encoding = llvm::dwarf::DW_ATE_unsigned; break; case BuiltinType::Short: case BuiltinType::Int: case BuiltinType::Long: case BuiltinType::LongLong: Encoding = llvm::dwarf::DW_ATE_signed; break; case BuiltinType::Bool: Encoding = llvm::dwarf::DW_ATE_boolean; break; case BuiltinType::Float: case BuiltinType::Double: Encoding = llvm::dwarf::DW_ATE_float; break; } // Bit size, align and offset of the type. uint64_t Size = M->getContext().getTypeSize(BT); uint64_t Align = M->getContext().getTypeAlign(BT); uint64_t Offset = 0; return DebugFactory.CreateBasicType(Unit, BT->getName(), Unit, 0, Size, Align, Offset, /*flags*/ 0, Encoding); } /// getOrCreateCVRType - Get the CVR qualified type from the cache or create /// a new one if necessary. llvm::DIType CGDebugInfo::CreateCVRType(QualType Ty, llvm::DICompileUnit Unit) { // We will create one Derived type for one qualifier and recurse to handle any // additional ones. llvm::DIType FromTy; unsigned Tag; if (Ty.isConstQualified()) { Tag = llvm::dwarf::DW_TAG_const_type; Ty.removeConst(); FromTy = getOrCreateType(Ty, Unit); } else if (Ty.isVolatileQualified()) { Tag = llvm::dwarf::DW_TAG_volatile_type; Ty.removeVolatile(); FromTy = getOrCreateType(Ty, Unit); } else { assert(Ty.isRestrictQualified() && "Unknown type qualifier for debug info"); Tag = llvm::dwarf::DW_TAG_restrict_type; Ty.removeRestrict(); FromTy = getOrCreateType(Ty, Unit); } // No need to fill in the Name, Line, Size, Alignment, Offset in case of // CVR derived types. return DebugFactory.CreateDerivedType(Tag, Unit, "", llvm::DICompileUnit(), 0, 0, 0, 0, 0, FromTy); } llvm::DIType CGDebugInfo::CreateType(const PointerType *Ty, llvm::DICompileUnit Unit) { llvm::DIType EltTy = getOrCreateType(Ty->getPointeeType(), Unit); // Bit size, align and offset of the type. uint64_t Size = M->getContext().getTypeSize(Ty); uint64_t Align = M->getContext().getTypeAlign(Ty); return DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_pointer_type, Unit, "", llvm::DICompileUnit(), 0, Size, Align, 0, 0, EltTy); } llvm::DIType CGDebugInfo::CreateType(const TypedefType *Ty, llvm::DICompileUnit Unit) { // Typedefs are derived from some other type. If we have a typedef of a // typedef, make sure to emit the whole chain. llvm::DIType Src = getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit); // We don't set size information, but do specify where the typedef was // declared. std::string TyName = Ty->getDecl()->getNameAsString(); SourceLocation DefLoc = Ty->getDecl()->getLocation(); llvm::DICompileUnit DefUnit = getOrCreateCompileUnit(DefLoc); SourceManager &SM = M->getContext().getSourceManager(); uint64_t Line = SM.getInstantiationLineNumber(DefLoc); return DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_typedef, Unit, TyName, DefUnit, Line, 0, 0, 0, 0, Src); } llvm::DIType CGDebugInfo::CreateType(const FunctionType *Ty, llvm::DICompileUnit Unit) { llvm::SmallVector EltTys; // Add the result type at least. EltTys.push_back(getOrCreateType(Ty->getResultType(), Unit)); // Set up remainder of arguments if there is a prototype. // FIXME: IF NOT, HOW IS THIS REPRESENTED? llvm-gcc doesn't represent '...'! if (const FunctionTypeProto *FTP = dyn_cast(Ty)) { for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i) EltTys.push_back(getOrCreateType(FTP->getArgType(i), Unit)); } else { // FIXME: Handle () case in C. llvm-gcc doesn't do it either. } llvm::DIArray EltTypeArray = DebugFactory.GetOrCreateArray(&EltTys[0], EltTys.size()); return DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_subroutine_type, Unit, "", llvm::DICompileUnit(), 0, 0, 0, 0, 0, llvm::DIType(), EltTypeArray); } /// getOrCreateRecordType - get structure or union type. llvm::DIType CGDebugInfo::CreateType(const RecordType *Ty, llvm::DICompileUnit Unit) { RecordDecl *Decl = Ty->getDecl(); unsigned Tag; if (Decl->isStruct()) Tag = llvm::dwarf::DW_TAG_structure_type; else if (Decl->isUnion()) Tag = llvm::dwarf::DW_TAG_union_type; else { assert(Decl->isClass() && "Unknown RecordType!"); Tag = llvm::dwarf::DW_TAG_class_type; } SourceManager &SM = M->getContext().getSourceManager(); // Get overall information about the record type for the debug info. std::string Name = Decl->getNameAsString(); llvm::DICompileUnit DefUnit = getOrCreateCompileUnit(Decl->getLocation()); unsigned Line = SM.getInstantiationLineNumber(Decl->getLocation()); // Records and classes and unions can all be recursive. To handle them, we // first generate a debug descriptor for the struct as a forward declaration. // Then (if it is a definition) we go through and get debug info for all of // its members. Finally, we create a descriptor for the complete type (which // may refer to the forward decl if the struct is recursive) and replace all // uses of the forward declaration with the final definition. llvm::DIType FwdDecl = DebugFactory.CreateCompositeType(Tag, Unit, Name, DefUnit, Line, 0, 0, 0, 0, llvm::DIType(), llvm::DIArray()); // If this is just a forward declaration, return it. if (!Decl->getDefinition(M->getContext())) return FwdDecl; // Otherwise, insert it into the TypeCache so that recursive uses will find // it. TypeCache[QualType(Ty, 0).getAsOpaquePtr()] = FwdDecl; // Convert all the elements. llvm::SmallVector EltTys; const ASTRecordLayout &RL = M->getContext().getASTRecordLayout(Decl); unsigned FieldNo = 0; for (RecordDecl::field_iterator I = Decl->field_begin(), E = Decl->field_end(); I != E; ++I, ++FieldNo) { FieldDecl *Field = *I; llvm::DIType FieldTy = getOrCreateType(Field->getType(), Unit); std::string FieldName = Field->getNameAsString(); // Get the location for the field. SourceLocation FieldDefLoc = Field->getLocation(); llvm::DICompileUnit FieldDefUnit = getOrCreateCompileUnit(FieldDefLoc); unsigned FieldLine = SM.getInstantiationLineNumber(FieldDefLoc); // Bit size, align and offset of the type. uint64_t FieldSize = M->getContext().getTypeSize(Ty); unsigned FieldAlign = M->getContext().getTypeAlign(Ty); uint64_t FieldOffset = RL.getFieldOffset(FieldNo); // Create a DW_TAG_member node to remember the offset of this field in the // struct. FIXME: This is an absolutely insane way to capture this // information. When we gut debug info, this should be fixed. FieldTy = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, Unit, FieldName, FieldDefUnit, FieldLine, FieldSize, FieldAlign, FieldOffset, 0, FieldTy); EltTys.push_back(FieldTy); } llvm::DIArray Elements = DebugFactory.GetOrCreateArray(&EltTys[0], EltTys.size()); // Bit size, align and offset of the type. uint64_t Size = M->getContext().getTypeSize(Ty); uint64_t Align = M->getContext().getTypeAlign(Ty); llvm::DIType RealDecl = DebugFactory.CreateCompositeType(Tag, Unit, Name, DefUnit, Line, Size, Align, 0, 0, llvm::DIType(), Elements); // Now that we have a real decl for the struct, replace anything using the // old decl with the new one. This will recursively update the debug info. FwdDecl.getGV()->replaceAllUsesWith(RealDecl.getGV()); FwdDecl.getGV()->eraseFromParent(); return RealDecl; } llvm::DIType CGDebugInfo::CreateType(const EnumType *Ty, llvm::DICompileUnit Unit) { EnumDecl *Decl = Ty->getDecl(); llvm::SmallVector Enumerators; // Create DIEnumerator elements for each enumerator. for (EnumDecl::enumerator_iterator Enum = Decl->enumerator_begin(), EnumEnd = Decl->enumerator_end(); Enum != EnumEnd; ++Enum) { Enumerators.push_back(DebugFactory.CreateEnumerator(Enum->getNameAsString(), Enum->getInitVal().getZExtValue())); } // Return a CompositeType for the enum itself. llvm::DIArray EltArray = DebugFactory.GetOrCreateArray(&Enumerators[0], Enumerators.size()); std::string EnumName = Decl->getNameAsString(); SourceLocation DefLoc = Decl->getLocation(); llvm::DICompileUnit DefUnit = getOrCreateCompileUnit(DefLoc); SourceManager &SM = M->getContext().getSourceManager(); unsigned Line = SM.getInstantiationLineNumber(DefLoc); // Size and align of the type. uint64_t Size = M->getContext().getTypeSize(Ty); unsigned Align = M->getContext().getTypeAlign(Ty); return DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_enumeration_type, Unit, EnumName, DefUnit, Line, Size, Align, 0, 0, llvm::DIType(), EltArray); } llvm::DIType CGDebugInfo::CreateType(const TagType *Ty, llvm::DICompileUnit Unit) { if (const RecordType *RT = dyn_cast(Ty)) return CreateType(RT, Unit); else if (const EnumType *ET = dyn_cast(Ty)) return CreateType(ET, Unit); return llvm::DIType(); } llvm::DIType CGDebugInfo::CreateType(const ArrayType *Ty, llvm::DICompileUnit Unit) { uint64_t Size; uint64_t Align; // FIXME: make getTypeAlign() aware of VLAs and incomplete array types if (const VariableArrayType *VAT = dyn_cast(Ty)) { Size = 0; Align = M->getContext().getTypeAlign(M->getContext().getBaseElementType(VAT)); } else if (Ty->isIncompleteArrayType()) { Size = 0; Align = M->getContext().getTypeAlign(Ty->getElementType()); } else { // Size and align of the whole array, not the element type. Size = M->getContext().getTypeSize(Ty); Align = M->getContext().getTypeAlign(Ty); } // Add the dimensions of the array. FIXME: This loses CV qualifiers from // interior arrays, do we care? Why aren't nested arrays represented the // obvious/recursive way? llvm::SmallVector Subscripts; QualType EltTy(Ty, 0); while ((Ty = dyn_cast(EltTy))) { uint64_t Upper = 0; if (const ConstantArrayType *CAT = dyn_cast(Ty)) Upper = CAT->getSize().getZExtValue() - 1; // FIXME: Verify this is right for VLAs. Subscripts.push_back(DebugFactory.GetOrCreateSubrange(0, Upper)); EltTy = Ty->getElementType(); } llvm::DIArray SubscriptArray = DebugFactory.GetOrCreateArray(&Subscripts[0], Subscripts.size()); return DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_array_type, Unit, "", llvm::DICompileUnit(), 0, Size, Align, 0, 0, getOrCreateType(EltTy, Unit), SubscriptArray); } /// getOrCreateType - Get the type from the cache or create a new /// one if necessary. llvm::DIType CGDebugInfo::getOrCreateType(QualType Ty, llvm::DICompileUnit Unit) { if (Ty.isNull()) return llvm::DIType(); // Check to see if the compile unit already has created this type. llvm::DIType &Slot = TypeCache[Ty.getAsOpaquePtr()]; if (!Slot.isNull()) return Slot; // Handle CVR qualifiers, which recursively handles what they refer to. if (Ty.getCVRQualifiers()) return Slot = CreateCVRType(Ty, Unit); // Work out details of type. switch (Ty->getTypeClass()) { case Type::Complex: case Type::Reference: case Type::Vector: case Type::ExtVector: case Type::ExtQual: case Type::ObjCInterface: case Type::ObjCQualifiedInterface: case Type::ObjCQualifiedId: default: return llvm::DIType(); case Type::Builtin: Slot = CreateType(cast(Ty), Unit); break; case Type::Pointer: Slot = CreateType(cast(Ty), Unit); break; case Type::TypeName: Slot = CreateType(cast(Ty), Unit); break; case Type::Tagged: Slot = CreateType(cast(Ty), Unit); break; case Type::FunctionProto: case Type::FunctionNoProto: return Slot = CreateType(cast(Ty), Unit); case Type::ConstantArray: case Type::VariableArray: case Type::IncompleteArray: return Slot = CreateType(cast(Ty), Unit); case Type::TypeOfExp: return Slot = getOrCreateType(cast(Ty)->getUnderlyingExpr() ->getType(), Unit); case Type::TypeOfTyp: return Slot = getOrCreateType(cast(Ty)->getUnderlyingType(), Unit); } return Slot; } /// EmitFunctionStart - Constructs the debug code for entering a function - /// "llvm.dbg.func.start.". void CGDebugInfo::EmitFunctionStart(const char *Name, QualType ReturnType, llvm::Function *Fn, CGBuilderTy &Builder) { // FIXME: Why is this using CurLoc??? llvm::DICompileUnit Unit = getOrCreateCompileUnit(CurLoc); SourceManager &SM = M->getContext().getSourceManager(); unsigned LineNo = SM.getInstantiationLineNumber(CurLoc); llvm::DISubprogram SP = DebugFactory.CreateSubprogram(Unit, Name, Name, "", Unit, LineNo, getOrCreateType(ReturnType, Unit), Fn->hasInternalLinkage(), true/*definition*/); DebugFactory.InsertSubprogramStart(SP, Builder.GetInsertBlock()); // Push function on region stack. RegionStack.push_back(SP); } void CGDebugInfo::EmitStopPoint(llvm::Function *Fn, CGBuilderTy &Builder) { if (CurLoc.isInvalid() || CurLoc.isMacroID()) return; // Don't bother if things are the same as last time. SourceManager &SM = M->getContext().getSourceManager(); if (CurLoc == PrevLoc || (SM.getInstantiationLineNumber(CurLoc) == SM.getInstantiationLineNumber(PrevLoc) && SM.isFromSameFile(CurLoc, PrevLoc))) return; // Update last state. PrevLoc = CurLoc; // Get the appropriate compile unit. llvm::DICompileUnit Unit = getOrCreateCompileUnit(CurLoc); DebugFactory.InsertStopPoint(Unit, SM.getInstantiationLineNumber(CurLoc), SM.getInstantiationColumnNumber(CurLoc), Builder.GetInsertBlock()); } /// EmitRegionStart- Constructs the debug code for entering a declarative /// region - "llvm.dbg.region.start.". void CGDebugInfo::EmitRegionStart(llvm::Function *Fn, CGBuilderTy &Builder) { llvm::DIDescriptor D; if (!RegionStack.empty()) D = RegionStack.back(); D = DebugFactory.CreateBlock(D); RegionStack.push_back(D); DebugFactory.InsertRegionStart(D, Builder.GetInsertBlock()); } /// EmitRegionEnd - Constructs the debug code for exiting a declarative /// region - "llvm.dbg.region.end." void CGDebugInfo::EmitRegionEnd(llvm::Function *Fn, CGBuilderTy &Builder) { assert(!RegionStack.empty() && "Region stack mismatch, stack empty!"); // Provide an region stop point. EmitStopPoint(Fn, Builder); DebugFactory.InsertRegionEnd(RegionStack.back(), Builder.GetInsertBlock()); RegionStack.pop_back(); } /// EmitDeclare - Emit local variable declaration debug info. void CGDebugInfo::EmitDeclare(const VarDecl *Decl, unsigned Tag, llvm::Value *Storage, CGBuilderTy &Builder) { assert(!RegionStack.empty() && "Region stack mismatch, stack empty!"); // Get location information. SourceManager &SM = M->getContext().getSourceManager(); unsigned Line = SM.getInstantiationLineNumber(Decl->getLocation()); llvm::DICompileUnit Unit = getOrCreateCompileUnit(Decl->getLocation()); // Create the descriptor for the variable. llvm::DIVariable D = DebugFactory.CreateVariable(Tag, RegionStack.back(),Decl->getNameAsString(), Unit, Line, getOrCreateType(Decl->getType(), Unit)); // Insert an llvm.dbg.declare into the current block. DebugFactory.InsertDeclare(Storage, D, Builder.GetInsertBlock()); } void CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *Decl, llvm::Value *Storage, CGBuilderTy &Builder) { EmitDeclare(Decl, llvm::dwarf::DW_TAG_auto_variable, Storage, Builder); } /// EmitDeclareOfArgVariable - Emit call to llvm.dbg.declare for an argument /// variable declaration. void CGDebugInfo::EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI, CGBuilderTy &Builder) { EmitDeclare(Decl, llvm::dwarf::DW_TAG_arg_variable, AI, Builder); } /// EmitGlobalVariable - Emit information about a global variable. void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var, const VarDecl *Decl) { // Create global variable debug descriptor. llvm::DICompileUnit Unit = getOrCreateCompileUnit(Decl->getLocation()); SourceManager &SM = M->getContext().getSourceManager(); unsigned LineNo = SM.getInstantiationLineNumber(Decl->getLocation()); std::string Name = Decl->getNameAsString(); QualType T = Decl->getType(); if (T->isIncompleteArrayType()) { // CodeGen turns int[] into int[1] so we'll do the same here. llvm::APSInt ConstVal(32); ConstVal = 1; QualType ET = M->getContext().getAsArrayType(T)->getElementType(); T = M->getContext().getConstantArrayType(ET, ConstVal, ArrayType::Normal, 0); } DebugFactory.CreateGlobalVariable(Unit, Name, Name, "", Unit, LineNo, getOrCreateType(T, Unit), Var->hasInternalLinkage(), true/*definition*/, Var); }