//===--- DebugInfo.cpp - Debug Information Helper Classes -----------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements the helper classes used to build and interpret debug // information in LLVM IR form. // //===----------------------------------------------------------------------===// #include "llvm/Analysis/DebugInfo.h" #include "llvm/Constants.h" #include "llvm/DerivedTypes.h" #include "llvm/Intrinsics.h" #include "llvm/Instructions.h" #include "llvm/Module.h" #include "llvm/Analysis/ValueTracking.h" #include "llvm/Support/Dwarf.h" using namespace llvm; //===----------------------------------------------------------------------===// // DIDescriptor //===----------------------------------------------------------------------===// DIDescriptor::DIDescriptor(GlobalVariable *gv, unsigned RequiredTag) { GV = gv; // If this is non-null, check to see if the Tag matches. If not, set to null. if (GV && getTag() != RequiredTag) GV = 0; } std::string DIDescriptor::getStringField(unsigned Elt) const { if (GV == 0) return ""; Constant *C = GV->getInitializer(); if (C == 0 || Elt >= C->getNumOperands()) return ""; std::string Result; // Fills in the string if it succeeds if (!GetConstantStringInfo(C->getOperand(Elt), Result)) Result.clear(); return Result; } uint64_t DIDescriptor::getUInt64Field(unsigned Elt) const { if (GV == 0) return 0; Constant *C = GV->getInitializer(); if (C == 0 || Elt >= C->getNumOperands()) return 0; if (ConstantInt *CI = dyn_cast(C->getOperand(Elt))) return CI->getZExtValue(); return 0; } DIDescriptor DIDescriptor::getDescriptorField(unsigned Elt) const { if (GV == 0) return DIDescriptor(); Constant *C = GV->getInitializer(); if (C == 0 || Elt >= C->getNumOperands()) return DIDescriptor(); C = C->getOperand(Elt); return DIDescriptor(dyn_cast(C->stripPointerCasts())); } GlobalVariable *DIDescriptor::getGlobalVariableField(unsigned Elt) const { if (GV == 0) return 0; Constant *C = GV->getInitializer(); if (C == 0 || Elt >= C->getNumOperands()) return 0; C = C->getOperand(Elt); return dyn_cast(C->stripPointerCasts()); } //===----------------------------------------------------------------------===// // Simple Descriptor Constructors and other Methods //===----------------------------------------------------------------------===// DIAnchor::DIAnchor(GlobalVariable *GV) : DIDescriptor(GV, dwarf::DW_TAG_anchor) {} DIEnumerator::DIEnumerator(GlobalVariable *GV) : DIDescriptor(GV, dwarf::DW_TAG_enumerator) {} DISubrange::DISubrange(GlobalVariable *GV) : DIDescriptor(GV, dwarf::DW_TAG_subrange_type) {} DICompileUnit::DICompileUnit(GlobalVariable *GV) : DIDescriptor(GV, dwarf::DW_TAG_compile_unit) {} DIBasicType::DIBasicType(GlobalVariable *GV) : DIType(GV, dwarf::DW_TAG_base_type) {} DISubprogram::DISubprogram(GlobalVariable *GV) : DIGlobal(GV, dwarf::DW_TAG_subprogram) {} DIGlobalVariable::DIGlobalVariable(GlobalVariable *GV) : DIGlobal(GV, dwarf::DW_TAG_variable) {} DIBlock::DIBlock(GlobalVariable *GV) : DIDescriptor(GV, dwarf::DW_TAG_lexical_block) {} /// isDerivedType - Return true if the specified tag is legal for /// DIDerivedType. bool DIDerivedType::isDerivedType(unsigned Tag) { switch (Tag) { case dwarf::DW_TAG_typedef: case dwarf::DW_TAG_pointer_type: case dwarf::DW_TAG_reference_type: case dwarf::DW_TAG_const_type: case dwarf::DW_TAG_volatile_type: case dwarf::DW_TAG_restrict_type: case dwarf::DW_TAG_member: case dwarf::DW_TAG_inheritance: return true; default: // FIXME: Even though it doesn't make sense, CompositeTypes are current // modelled as DerivedTypes, this should return true for them as well. return false; } } DIDerivedType::DIDerivedType(GlobalVariable *GV) : DIType(GV, true, true) { if (GV && !isDerivedType(getTag())) GV = 0; } /// isCompositeType - Return true if the specified tag is legal for /// DICompositeType. bool DICompositeType::isCompositeType(unsigned TAG) { switch (TAG) { case dwarf::DW_TAG_array_type: case dwarf::DW_TAG_structure_type: case dwarf::DW_TAG_union_type: case dwarf::DW_TAG_enumeration_type: case dwarf::DW_TAG_vector_type: case dwarf::DW_TAG_subroutine_type: return true; default: return false; } } DICompositeType::DICompositeType(GlobalVariable *GV) : DIDerivedType(GV, true, true) { if (GV && !isCompositeType(getTag())) GV = 0; } /// isVariable - Return true if the specified tag is legal for DIVariable. bool DIVariable::isVariable(unsigned Tag) { switch (Tag) { case dwarf::DW_TAG_auto_variable: case dwarf::DW_TAG_arg_variable: case dwarf::DW_TAG_return_variable: return true; default: return false; } } DIVariable::DIVariable(GlobalVariable *GV) : DIDescriptor(GV) { if (GV && !isVariable(getTag())) GV = 0; } //===----------------------------------------------------------------------===// // DIFactory: Basic Helpers //===----------------------------------------------------------------------===// DIFactory::DIFactory(Module &m) : M(m) { StopPointFn = FuncStartFn = RegionStartFn = RegionEndFn = DeclareFn = 0; EmptyStructPtr = PointerType::getUnqual(StructType::get(NULL, NULL)); } /// getCastToEmpty - Return this descriptor as a Constant* with type '{}*'. /// This is only valid when the descriptor is non-null. Constant *DIFactory::getCastToEmpty(DIDescriptor D) { if (D.isNull()) return Constant::getNullValue(EmptyStructPtr); return ConstantExpr::getBitCast(D.getGV(), EmptyStructPtr); } Constant *DIFactory::GetTagConstant(unsigned TAG) { assert((TAG & DIDescriptor::VersionMask) == 0 && "Tag too large for debug encoding!"); return ConstantInt::get(Type::Int32Ty, TAG | DIDescriptor::Version6); } Constant *DIFactory::GetStringConstant(const std::string &String) { // Check string cache for previous edition. Constant *&Slot = StringCache[String]; // Return Constant if previously defined. if (Slot) return Slot; const PointerType *DestTy = PointerType::getUnqual(Type::Int8Ty); // If empty string then use a sbyte* null instead. if (String.empty()) return Slot = ConstantPointerNull::get(DestTy); // Construct string as an llvm constant. Constant *ConstStr = ConstantArray::get(String); // Otherwise create and return a new string global. GlobalVariable *StrGV = new GlobalVariable(ConstStr->getType(), true, GlobalVariable::InternalLinkage, ConstStr, ".str", &M); StrGV->setSection("llvm.metadata"); return Slot = ConstantExpr::getBitCast(StrGV, DestTy); } /// GetOrCreateAnchor - Look up an anchor for the specified tag and name. If it /// already exists, return it. If not, create a new one and return it. DIAnchor DIFactory::GetOrCreateAnchor(unsigned TAG, const char *Name) { const Type *EltTy = StructType::get(Type::Int32Ty, Type::Int32Ty, NULL); // Otherwise, create the global or return it if already in the module. Constant *C = M.getOrInsertGlobal(Name, EltTy); assert(isa(C) && "Incorrectly typed anchor?"); GlobalVariable *GV = cast(C); // If it has an initializer, it is already in the module. if (GV->hasInitializer()) return SubProgramAnchor = DIAnchor(GV); GV->setLinkage(GlobalValue::LinkOnceLinkage); GV->setSection("llvm.metadata"); GV->setConstant(true); M.addTypeName("llvm.dbg.anchor.type", EltTy); // Otherwise, set the initializer. Constant *Elts[] = { GetTagConstant(dwarf::DW_TAG_anchor), ConstantInt::get(Type::Int32Ty, TAG) }; GV->setInitializer(ConstantStruct::get(Elts, 2)); return DIAnchor(GV); } //===----------------------------------------------------------------------===// // DIFactory: Primary Constructors //===----------------------------------------------------------------------===// /// GetOrCreateCompileUnitAnchor - Return the anchor for compile units, /// creating a new one if there isn't already one in the module. DIAnchor DIFactory::GetOrCreateCompileUnitAnchor() { // If we already created one, just return it. if (!CompileUnitAnchor.isNull()) return CompileUnitAnchor; return CompileUnitAnchor = GetOrCreateAnchor(dwarf::DW_TAG_compile_unit, "llvm.dbg.compile_units"); } /// GetOrCreateSubprogramAnchor - Return the anchor for subprograms, /// creating a new one if there isn't already one in the module. DIAnchor DIFactory::GetOrCreateSubprogramAnchor() { // If we already created one, just return it. if (!SubProgramAnchor.isNull()) return SubProgramAnchor; return SubProgramAnchor = GetOrCreateAnchor(dwarf::DW_TAG_subprogram, "llvm.dbg.subprograms"); } /// GetOrCreateGlobalVariableAnchor - Return the anchor for globals, /// creating a new one if there isn't already one in the module. DIAnchor DIFactory::GetOrCreateGlobalVariableAnchor() { // If we already created one, just return it. if (!GlobalVariableAnchor.isNull()) return GlobalVariableAnchor; return GlobalVariableAnchor = GetOrCreateAnchor(dwarf::DW_TAG_variable, "llvm.dbg.global_variables"); } /// GetOrCreateArray - Create an descriptor for an array of descriptors. /// This implicitly uniques the arrays created. DIArray DIFactory::GetOrCreateArray(DIDescriptor *Tys, unsigned NumTys) { SmallVector Elts; for (unsigned i = 0; i != NumTys; ++i) Elts.push_back(getCastToEmpty(Tys[i])); Constant *Init = ConstantArray::get(ArrayType::get(EmptyStructPtr, Elts.size()), &Elts[0], Elts.size()); // If we already have this array, just return the uniqued version. DIDescriptor &Entry = SimpleConstantCache[Init]; if (!Entry.isNull()) return DIArray(Entry.getGV()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.array", &M); GV->setSection("llvm.metadata"); Entry = DIDescriptor(GV); return DIArray(GV); } /// GetOrCreateSubrange - Create a descriptor for a value range. This /// implicitly uniques the values returned. DISubrange DIFactory::GetOrCreateSubrange(int64_t Lo, int64_t Hi) { Constant *Elts[] = { GetTagConstant(dwarf::DW_TAG_subrange_type), ConstantInt::get(Type::Int64Ty, Lo), ConstantInt::get(Type::Int64Ty, Hi) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); // If we already have this range, just return the uniqued version. DIDescriptor &Entry = SimpleConstantCache[Init]; if (!Entry.isNull()) return DISubrange(Entry.getGV()); M.addTypeName("llvm.dbg.subrange.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.subrange", &M); GV->setSection("llvm.metadata"); Entry = DIDescriptor(GV); return DISubrange(GV); } /// CreateCompileUnit - Create a new descriptor for the specified compile /// unit. Note that this does not unique compile units within the module. DICompileUnit DIFactory::CreateCompileUnit(unsigned LangID, const std::string &Filename, const std::string &Directory, const std::string &Producer) { Constant *Elts[] = { GetTagConstant(dwarf::DW_TAG_compile_unit), getCastToEmpty(GetOrCreateCompileUnitAnchor()), ConstantInt::get(Type::Int32Ty, LangID), GetStringConstant(Filename), GetStringConstant(Directory), GetStringConstant(Producer) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.compile_unit.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.compile_unit", &M); GV->setSection("llvm.metadata"); return DICompileUnit(GV); } /// CreateEnumerator - Create a single enumerator value. DIEnumerator DIFactory::CreateEnumerator(const std::string &Name, uint64_t Val){ Constant *Elts[] = { GetTagConstant(dwarf::DW_TAG_enumerator), GetStringConstant(Name), ConstantInt::get(Type::Int64Ty, Val) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.enumerator.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.enumerator", &M); GV->setSection("llvm.metadata"); return DIEnumerator(GV); } /// CreateBasicType - Create a basic type like int, float, etc. DIBasicType DIFactory::CreateBasicType(DIDescriptor Context, const std::string &Name, DICompileUnit CompileUnit, unsigned LineNumber, uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits, unsigned Flags, unsigned Encoding) { Constant *Elts[] = { GetTagConstant(dwarf::DW_TAG_base_type), getCastToEmpty(Context), GetStringConstant(Name), getCastToEmpty(CompileUnit), ConstantInt::get(Type::Int32Ty, LineNumber), ConstantInt::get(Type::Int64Ty, SizeInBits), ConstantInt::get(Type::Int64Ty, AlignInBits), ConstantInt::get(Type::Int64Ty, OffsetInBits), ConstantInt::get(Type::Int32Ty, Flags), ConstantInt::get(Type::Int32Ty, Encoding) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.basictype.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.basictype", &M); GV->setSection("llvm.metadata"); return DIBasicType(GV); } /// CreateDerivedType - Create a derived type like const qualified type, /// pointer, typedef, etc. DIDerivedType DIFactory::CreateDerivedType(unsigned Tag, DIDescriptor Context, const std::string &Name, DICompileUnit CompileUnit, unsigned LineNumber, uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits, unsigned Flags, DIType DerivedFrom) { Constant *Elts[] = { GetTagConstant(Tag), getCastToEmpty(Context), GetStringConstant(Name), getCastToEmpty(CompileUnit), ConstantInt::get(Type::Int32Ty, LineNumber), ConstantInt::get(Type::Int64Ty, SizeInBits), ConstantInt::get(Type::Int64Ty, AlignInBits), ConstantInt::get(Type::Int64Ty, OffsetInBits), ConstantInt::get(Type::Int32Ty, Flags), getCastToEmpty(DerivedFrom) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.derivedtype.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.derivedtype", &M); GV->setSection("llvm.metadata"); return DIDerivedType(GV); } /// CreateCompositeType - Create a composite type like array, struct, etc. DICompositeType DIFactory::CreateCompositeType(unsigned Tag, DIDescriptor Context, const std::string &Name, DICompileUnit CompileUnit, unsigned LineNumber, uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits, unsigned Flags, DIType DerivedFrom, DIArray Elements) { Constant *Elts[] = { GetTagConstant(Tag), getCastToEmpty(Context), GetStringConstant(Name), getCastToEmpty(CompileUnit), ConstantInt::get(Type::Int32Ty, LineNumber), ConstantInt::get(Type::Int64Ty, SizeInBits), ConstantInt::get(Type::Int64Ty, AlignInBits), ConstantInt::get(Type::Int64Ty, OffsetInBits), ConstantInt::get(Type::Int32Ty, Flags), getCastToEmpty(DerivedFrom), getCastToEmpty(Elements) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.composite.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.composite", &M); GV->setSection("llvm.metadata"); return DICompositeType(GV); } /// CreateSubprogram - Create a new descriptor for the specified subprogram. /// See comments in DISubprogram for descriptions of these fields. This /// method does not unique the generated descriptors. DISubprogram DIFactory::CreateSubprogram(DIDescriptor Context, const std::string &Name, const std::string &DisplayName, const std::string &LinkageName, DICompileUnit CompileUnit, unsigned LineNo, DIType Type, bool isLocalToUnit, bool isDefinition) { Constant *Elts[] = { GetTagConstant(dwarf::DW_TAG_subprogram), getCastToEmpty(GetOrCreateSubprogramAnchor()), getCastToEmpty(Context), GetStringConstant(Name), GetStringConstant(DisplayName), GetStringConstant(LinkageName), getCastToEmpty(CompileUnit), ConstantInt::get(Type::Int32Ty, LineNo), getCastToEmpty(Type), ConstantInt::get(Type::Int1Ty, isLocalToUnit), ConstantInt::get(Type::Int1Ty, isDefinition) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.subprogram.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.subprogram", &M); GV->setSection("llvm.metadata"); return DISubprogram(GV); } /// CreateGlobalVariable - Create a new descriptor for the specified global. DIGlobalVariable DIFactory::CreateGlobalVariable(DIDescriptor Context, const std::string &Name, const std::string &DisplayName, const std::string &LinkageName, DICompileUnit CompileUnit, unsigned LineNo, DIType Type,bool isLocalToUnit, bool isDefinition, llvm::GlobalVariable *Val) { Constant *Elts[] = { GetTagConstant(dwarf::DW_TAG_variable), getCastToEmpty(GetOrCreateGlobalVariableAnchor()), getCastToEmpty(Context), GetStringConstant(Name), GetStringConstant(DisplayName), GetStringConstant(LinkageName), getCastToEmpty(CompileUnit), ConstantInt::get(Type::Int32Ty, LineNo), getCastToEmpty(Type), ConstantInt::get(Type::Int1Ty, isLocalToUnit), ConstantInt::get(Type::Int1Ty, isDefinition), ConstantExpr::getBitCast(Val, EmptyStructPtr) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.global_variable.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.global_variable", &M); GV->setSection("llvm.metadata"); return DIGlobalVariable(GV); } /// CreateVariable - Create a new descriptor for the specified variable. DIVariable DIFactory::CreateVariable(unsigned Tag, DIDescriptor Context, const std::string &Name, DICompileUnit CompileUnit, unsigned LineNo, DIType Type) { Constant *Elts[] = { GetTagConstant(Tag), getCastToEmpty(Context), GetStringConstant(Name), getCastToEmpty(CompileUnit), ConstantInt::get(Type::Int32Ty, LineNo), getCastToEmpty(Type), }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.variable.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.variable", &M); GV->setSection("llvm.metadata"); return DIVariable(GV); } /// CreateBlock - This creates a descriptor for a lexical block with the /// specified parent context. DIBlock DIFactory::CreateBlock(DIDescriptor Context) { Constant *Elts[] = { GetTagConstant(dwarf::DW_TAG_lexical_block), getCastToEmpty(Context) }; Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0])); M.addTypeName("llvm.dbg.block.type", Init->getType()); GlobalVariable *GV = new GlobalVariable(Init->getType(), true, GlobalValue::InternalLinkage, Init, "llvm.dbg.block", &M); GV->setSection("llvm.metadata"); return DIBlock(GV); } //===----------------------------------------------------------------------===// // DIFactory: Routines for inserting code into a function //===----------------------------------------------------------------------===// /// InsertStopPoint - Create a new llvm.dbg.stoppoint intrinsic invocation, /// inserting it at the end of the specified basic block. void DIFactory::InsertStopPoint(DICompileUnit CU, unsigned LineNo, unsigned ColNo, BasicBlock *BB) { // Lazily construct llvm.dbg.stoppoint function. if (!StopPointFn) StopPointFn = llvm::Intrinsic::getDeclaration(&M, llvm::Intrinsic::dbg_stoppoint); // Invoke llvm.dbg.stoppoint Value *Args[] = { llvm::ConstantInt::get(llvm::Type::Int32Ty, LineNo), llvm::ConstantInt::get(llvm::Type::Int32Ty, ColNo), getCastToEmpty(CU) }; CallInst::Create(StopPointFn, Args, Args+3, "", BB); } /// InsertSubprogramStart - Create a new llvm.dbg.func.start intrinsic to /// mark the start of the specified subprogram. void DIFactory::InsertSubprogramStart(DISubprogram SP, BasicBlock *BB) { // Lazily construct llvm.dbg.func.start. if (!FuncStartFn) FuncStartFn = llvm::Intrinsic::getDeclaration(&M, llvm::Intrinsic::dbg_func_start); // Call llvm.dbg.func.start which also implicitly sets a stoppoint. CallInst::Create(FuncStartFn, getCastToEmpty(SP), "", BB); } /// InsertRegionStart - Insert a new llvm.dbg.region.start intrinsic call to /// mark the start of a region for the specified scoping descriptor. void DIFactory::InsertRegionStart(DIDescriptor D, BasicBlock *BB) { // Lazily construct llvm.dbg.region.start function. if (!RegionStartFn) RegionStartFn = llvm::Intrinsic::getDeclaration(&M, llvm::Intrinsic::dbg_region_start); // Call llvm.dbg.func.start. CallInst::Create(RegionStartFn, getCastToEmpty(D), "", BB); } /// InsertRegionEnd - Insert a new llvm.dbg.region.end intrinsic call to /// mark the end of a region for the specified scoping descriptor. void DIFactory::InsertRegionEnd(DIDescriptor D, BasicBlock *BB) { // Lazily construct llvm.dbg.region.end function. if (!RegionEndFn) RegionEndFn = llvm::Intrinsic::getDeclaration(&M, llvm::Intrinsic::dbg_region_end); CallInst::Create(RegionEndFn, getCastToEmpty(D), "", BB); } /// InsertDeclare - Insert a new llvm.dbg.declare intrinsic call. void DIFactory::InsertDeclare(llvm::Value *Storage, DIVariable D, BasicBlock *BB) { // Cast the storage to a {}* for the call to llvm.dbg.declare. Storage = new llvm::BitCastInst(Storage, EmptyStructPtr, "", BB); if (!DeclareFn) DeclareFn = llvm::Intrinsic::getDeclaration(&M, llvm::Intrinsic::dbg_declare); Value *Args[] = { Storage, getCastToEmpty(D) }; CallInst::Create(DeclareFn, Args, Args+2, "", BB); }