1 //===- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h --------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains support for writing Microsoft CodeView debug info.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
15 #define LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
17 #include "DbgValueHistoryCalculator.h"
18 #include "DebugHandlerBase.h"
19 #include "llvm/ADT/ArrayRef.h"
20 #include "llvm/ADT/DenseMap.h"
21 #include "llvm/ADT/DenseSet.h"
22 #include "llvm/ADT/MapVector.h"
23 #include "llvm/ADT/SetVector.h"
24 #include "llvm/ADT/SmallVector.h"
25 #include "llvm/DebugInfo/CodeView/CodeView.h"
26 #include "llvm/DebugInfo/CodeView/GlobalTypeTableBuilder.h"
27 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
28 #include "llvm/IR/DebugLoc.h"
29 #include "llvm/Support/Allocator.h"
30 #include "llvm/Support/Compiler.h"
35 #include <unordered_map>
49 class MachineFunction;
51 /// \brief Collects and handles line tables information in a CodeView format.
52 class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
54 BumpPtrAllocator Allocator;
55 codeview::GlobalTypeTableBuilder TypeTable;
57 /// Represents the most general definition range.
58 struct LocalVarDefRange {
59 /// Indicates that variable data is stored in memory relative to the
60 /// specified register.
63 /// Offset of variable data in memory.
66 /// Non-zero if this is a piece of an aggregate.
67 uint16_t IsSubfield : 1;
69 /// Offset into aggregate.
70 uint16_t StructOffset : 15;
72 /// Register containing the data or the register base of the memory
73 /// location containing the data.
76 /// Compares all location fields. This includes all fields except the label
78 bool isDifferentLocation(LocalVarDefRange &O) {
79 return InMemory != O.InMemory || DataOffset != O.DataOffset ||
80 IsSubfield != O.IsSubfield || StructOffset != O.StructOffset ||
81 CVRegister != O.CVRegister;
84 SmallVector<std::pair<const MCSymbol *, const MCSymbol *>, 1> Ranges;
87 static LocalVarDefRange createDefRangeMem(uint16_t CVRegister, int Offset);
88 static LocalVarDefRange createDefRangeGeneral(uint16_t CVRegister,
89 bool InMemory, int Offset,
91 uint16_t StructOffset);
93 /// Similar to DbgVariable in DwarfDebug, but not dwarf-specific.
94 struct LocalVariable {
95 const DILocalVariable *DIVar = nullptr;
96 SmallVector<LocalVarDefRange, 1> DefRanges;
97 bool UseReferenceType = false;
101 SmallVector<LocalVariable, 1> InlinedLocals;
102 SmallVector<const DILocation *, 1> ChildSites;
103 const DISubprogram *Inlinee = nullptr;
105 /// The ID of the inline site or function used with .cv_loc. Not a type
107 unsigned SiteFuncId = 0;
110 // For each function, store a vector of labels to its instructions, as well as
111 // to the end of the function.
112 struct FunctionInfo {
113 /// Map from inlined call site to inlined instructions and child inlined
114 /// call sites. Listed in program order.
115 std::unordered_map<const DILocation *, InlineSite> InlineSites;
117 /// Ordered list of top-level inlined call sites.
118 SmallVector<const DILocation *, 1> ChildSites;
120 SmallVector<LocalVariable, 1> Locals;
122 std::vector<std::pair<MCSymbol *, MDNode *>> Annotations;
124 const MCSymbol *Begin = nullptr;
125 const MCSymbol *End = nullptr;
127 unsigned LastFileId = 0;
128 bool HaveLineInfo = false;
130 FunctionInfo *CurFn = nullptr;
132 /// The set of comdat .debug$S sections that we've seen so far. Each section
133 /// must start with a magic version number that must only be emitted once.
134 /// This set tracks which sections we've already opened.
135 DenseSet<MCSectionCOFF *> ComdatDebugSections;
137 /// Switch to the appropriate .debug$S section for GVSym. If GVSym, the symbol
138 /// of an emitted global value, is in a comdat COFF section, this will switch
139 /// to a new .debug$S section in that comdat. This method ensures that the
140 /// section starts with the magic version number on first use. If GVSym is
141 /// null, uses the main .debug$S section.
142 void switchToDebugSectionForSymbol(const MCSymbol *GVSym);
144 /// The next available function index for use with our .cv_* directives. Not
145 /// to be confused with type indices for LF_FUNC_ID records.
146 unsigned NextFuncId = 0;
148 InlineSite &getInlineSite(const DILocation *InlinedAt,
149 const DISubprogram *Inlinee);
151 codeview::TypeIndex getFuncIdForSubprogram(const DISubprogram *SP);
153 void calculateRanges(LocalVariable &Var,
154 const DbgValueHistoryMap::InstrRanges &Ranges);
156 static void collectInlineSiteChildren(SmallVectorImpl<unsigned> &Children,
157 const FunctionInfo &FI,
158 const InlineSite &Site);
160 /// Remember some debug info about each function. Keep it in a stable order to
161 /// emit at the end of the TU.
162 MapVector<const Function *, FunctionInfo> FnDebugInfo;
164 /// Map from full file path to .cv_file id. Full paths are built from DIFiles
165 /// and are stored in FileToFilepathMap;
166 DenseMap<StringRef, unsigned> FileIdMap;
168 /// All inlined subprograms in the order they should be emitted.
169 SmallSetVector<const DISubprogram *, 4> InlinedSubprograms;
171 /// Map from a pair of DI metadata nodes and its DI type (or scope) that can
172 /// be nullptr, to CodeView type indices. Primarily indexed by
173 /// {DIType*, DIType*} and {DISubprogram*, DIType*}.
175 /// The second entry in the key is needed for methods as DISubroutineType
176 /// representing static method type are shared with non-method function type.
177 DenseMap<std::pair<const DINode *, const DIType *>, codeview::TypeIndex>
180 /// Map from DICompositeType* to complete type index. Non-record types are
181 /// always looked up in the normal TypeIndices map.
182 DenseMap<const DICompositeType *, codeview::TypeIndex> CompleteTypeIndices;
184 /// Complete record types to emit after all active type lowerings are
186 SmallVector<const DICompositeType *, 4> DeferredCompleteTypes;
188 /// Number of type lowering frames active on the stack.
189 unsigned TypeEmissionLevel = 0;
191 codeview::TypeIndex VBPType;
193 const DISubprogram *CurrentSubprogram = nullptr;
195 // The UDTs we have seen while processing types; each entry is a pair of type
196 // index and type name.
197 std::vector<std::pair<std::string, const DIType *>> LocalUDTs;
198 std::vector<std::pair<std::string, const DIType *>> GlobalUDTs;
200 using FileToFilepathMapTy = std::map<const DIFile *, std::string>;
201 FileToFilepathMapTy FileToFilepathMap;
203 StringRef getFullFilepath(const DIFile *S);
205 unsigned maybeRecordFile(const DIFile *F);
207 void maybeRecordLocation(const DebugLoc &DL, const MachineFunction *MF);
211 void setCurrentSubprogram(const DISubprogram *SP) {
212 CurrentSubprogram = SP;
216 /// Emit the magic version number at the start of a CodeView type or symbol
217 /// section. Appears at the front of every .debug$S or .debug$T section.
218 void emitCodeViewMagicVersion();
220 void emitTypeInformation();
222 void emitTypeGlobalHashes();
224 void emitCompilerInformation();
226 void emitInlineeLinesSubsection();
228 void emitDebugInfoForFunction(const Function *GV, FunctionInfo &FI);
230 void emitDebugInfoForGlobals();
232 void emitDebugInfoForRetainedTypes();
235 emitDebugInfoForUDTs(ArrayRef<std::pair<std::string, const DIType *>> UDTs);
237 void emitDebugInfoForGlobal(const DIGlobalVariable *DIGV,
238 const GlobalVariable *GV, MCSymbol *GVSym);
240 /// Opens a subsection of the given kind in a .debug$S codeview section.
241 /// Returns an end label for use with endCVSubsection when the subsection is
243 MCSymbol *beginCVSubsection(codeview::DebugSubsectionKind Kind);
245 void endCVSubsection(MCSymbol *EndLabel);
247 void emitInlinedCallSite(const FunctionInfo &FI, const DILocation *InlinedAt,
248 const InlineSite &Site);
250 using InlinedVariable = DbgValueHistoryMap::InlinedVariable;
252 void collectVariableInfo(const DISubprogram *SP);
254 void collectVariableInfoFromMFTable(DenseSet<InlinedVariable> &Processed);
256 /// Records information about a local variable in the appropriate scope. In
257 /// particular, locals from inlined code live inside the inlining site.
258 void recordLocalVariable(LocalVariable &&Var, const DILocation *Loc);
260 /// Emits local variables in the appropriate order.
261 void emitLocalVariableList(ArrayRef<LocalVariable> Locals);
263 /// Emits an S_LOCAL record and its associated defined ranges.
264 void emitLocalVariable(const LocalVariable &Var);
266 /// Translates the DIType to codeview if necessary and returns a type index
268 codeview::TypeIndex getTypeIndex(DITypeRef TypeRef,
269 DITypeRef ClassTyRef = DITypeRef());
271 codeview::TypeIndex getTypeIndexForReferenceTo(DITypeRef TypeRef);
273 codeview::TypeIndex getMemberFunctionType(const DISubprogram *SP,
274 const DICompositeType *Class);
276 codeview::TypeIndex getScopeIndex(const DIScope *Scope);
278 codeview::TypeIndex getVBPTypeIndex();
280 void addToUDTs(const DIType *Ty);
282 codeview::TypeIndex lowerType(const DIType *Ty, const DIType *ClassTy);
283 codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty);
284 codeview::TypeIndex lowerTypeArray(const DICompositeType *Ty);
285 codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty);
286 codeview::TypeIndex lowerTypePointer(const DIDerivedType *Ty);
287 codeview::TypeIndex lowerTypeMemberPointer(const DIDerivedType *Ty);
288 codeview::TypeIndex lowerTypeModifier(const DIDerivedType *Ty);
289 codeview::TypeIndex lowerTypeFunction(const DISubroutineType *Ty);
290 codeview::TypeIndex lowerTypeVFTableShape(const DIDerivedType *Ty);
291 codeview::TypeIndex lowerTypeMemberFunction(const DISubroutineType *Ty,
292 const DIType *ClassTy,
294 bool IsStaticMethod);
295 codeview::TypeIndex lowerTypeEnum(const DICompositeType *Ty);
296 codeview::TypeIndex lowerTypeClass(const DICompositeType *Ty);
297 codeview::TypeIndex lowerTypeUnion(const DICompositeType *Ty);
299 /// Symbol records should point to complete types, but type records should
300 /// always point to incomplete types to avoid cycles in the type graph. Only
301 /// use this entry point when generating symbol records. The complete and
302 /// incomplete type indices only differ for record types. All other types use
304 codeview::TypeIndex getCompleteTypeIndex(DITypeRef TypeRef);
306 codeview::TypeIndex lowerCompleteTypeClass(const DICompositeType *Ty);
307 codeview::TypeIndex lowerCompleteTypeUnion(const DICompositeType *Ty);
309 struct TypeLoweringScope;
311 void emitDeferredCompleteTypes();
313 void collectMemberInfo(ClassInfo &Info, const DIDerivedType *DDTy);
314 ClassInfo collectClassInfo(const DICompositeType *Ty);
316 /// Common record member lowering functionality for record types, which are
317 /// structs, classes, and unions. Returns the field list index and the member
319 std::tuple<codeview::TypeIndex, codeview::TypeIndex, unsigned, bool>
320 lowerRecordFieldList(const DICompositeType *Ty);
322 /// Inserts {{Node, ClassTy}, TI} into TypeIndices and checks for duplicates.
323 codeview::TypeIndex recordTypeIndexForDINode(const DINode *Node,
324 codeview::TypeIndex TI,
325 const DIType *ClassTy = nullptr);
327 unsigned getPointerSizeInBytes();
330 /// \brief Gather pre-function debug information.
331 void beginFunctionImpl(const MachineFunction *MF) override;
333 /// \brief Gather post-function debug information.
334 void endFunctionImpl(const MachineFunction *) override;
337 CodeViewDebug(AsmPrinter *Asm);
339 void setSymbolSize(const MCSymbol *, uint64_t) override {}
341 /// \brief Emit the COFF section that holds the line table information.
342 void endModule() override;
344 /// \brief Process beginning of an instruction.
345 void beginInstruction(const MachineInstr *MI) override;
348 } // end namespace llvm
350 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H