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 /// 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 // Combines information from DILexicalBlock and LexicalScope.
111 struct LexicalBlock {
112 SmallVector<LocalVariable, 1> Locals;
113 SmallVector<LexicalBlock *, 1> Children;
114 const MCSymbol *Begin;
119 // For each function, store a vector of labels to its instructions, as well as
120 // to the end of the function.
121 struct FunctionInfo {
122 FunctionInfo() = default;
125 FunctionInfo(const FunctionInfo &FI) = delete;
127 /// Map from inlined call site to inlined instructions and child inlined
128 /// call sites. Listed in program order.
129 std::unordered_map<const DILocation *, InlineSite> InlineSites;
131 /// Ordered list of top-level inlined call sites.
132 SmallVector<const DILocation *, 1> ChildSites;
134 SmallVector<LocalVariable, 1> Locals;
136 std::unordered_map<const DILexicalBlockBase*, LexicalBlock> LexicalBlocks;
138 // Lexical blocks containing local variables.
139 SmallVector<LexicalBlock *, 1> ChildBlocks;
141 std::vector<std::pair<MCSymbol *, MDNode *>> Annotations;
143 const MCSymbol *Begin = nullptr;
144 const MCSymbol *End = nullptr;
146 unsigned LastFileId = 0;
147 bool HaveLineInfo = false;
149 FunctionInfo *CurFn = nullptr;
151 // Map used to seperate variables according to the lexical scope they belong
152 // in. This is populated by recordLocalVariable() before
153 // collectLexicalBlocks() separates the variables between the FunctionInfo
154 // and LexicalBlocks.
155 DenseMap<const LexicalScope *, SmallVector<LocalVariable, 1>> ScopeVariables;
157 /// The set of comdat .debug$S sections that we've seen so far. Each section
158 /// must start with a magic version number that must only be emitted once.
159 /// This set tracks which sections we've already opened.
160 DenseSet<MCSectionCOFF *> ComdatDebugSections;
162 /// Switch to the appropriate .debug$S section for GVSym. If GVSym, the symbol
163 /// of an emitted global value, is in a comdat COFF section, this will switch
164 /// to a new .debug$S section in that comdat. This method ensures that the
165 /// section starts with the magic version number on first use. If GVSym is
166 /// null, uses the main .debug$S section.
167 void switchToDebugSectionForSymbol(const MCSymbol *GVSym);
169 /// The next available function index for use with our .cv_* directives. Not
170 /// to be confused with type indices for LF_FUNC_ID records.
171 unsigned NextFuncId = 0;
173 InlineSite &getInlineSite(const DILocation *InlinedAt,
174 const DISubprogram *Inlinee);
176 codeview::TypeIndex getFuncIdForSubprogram(const DISubprogram *SP);
178 void calculateRanges(LocalVariable &Var,
179 const DbgValueHistoryMap::InstrRanges &Ranges);
181 static void collectInlineSiteChildren(SmallVectorImpl<unsigned> &Children,
182 const FunctionInfo &FI,
183 const InlineSite &Site);
185 /// Remember some debug info about each function. Keep it in a stable order to
186 /// emit at the end of the TU.
187 MapVector<const Function *, std::unique_ptr<FunctionInfo>> FnDebugInfo;
189 /// Map from full file path to .cv_file id. Full paths are built from DIFiles
190 /// and are stored in FileToFilepathMap;
191 DenseMap<StringRef, unsigned> FileIdMap;
193 /// All inlined subprograms in the order they should be emitted.
194 SmallSetVector<const DISubprogram *, 4> InlinedSubprograms;
196 /// Map from a pair of DI metadata nodes and its DI type (or scope) that can
197 /// be nullptr, to CodeView type indices. Primarily indexed by
198 /// {DIType*, DIType*} and {DISubprogram*, DIType*}.
200 /// The second entry in the key is needed for methods as DISubroutineType
201 /// representing static method type are shared with non-method function type.
202 DenseMap<std::pair<const DINode *, const DIType *>, codeview::TypeIndex>
205 /// Map from DICompositeType* to complete type index. Non-record types are
206 /// always looked up in the normal TypeIndices map.
207 DenseMap<const DICompositeType *, codeview::TypeIndex> CompleteTypeIndices;
209 /// Complete record types to emit after all active type lowerings are
211 SmallVector<const DICompositeType *, 4> DeferredCompleteTypes;
213 /// Number of type lowering frames active on the stack.
214 unsigned TypeEmissionLevel = 0;
216 codeview::TypeIndex VBPType;
218 const DISubprogram *CurrentSubprogram = nullptr;
220 // The UDTs we have seen while processing types; each entry is a pair of type
221 // index and type name.
222 std::vector<std::pair<std::string, const DIType *>> LocalUDTs;
223 std::vector<std::pair<std::string, const DIType *>> GlobalUDTs;
225 using FileToFilepathMapTy = std::map<const DIFile *, std::string>;
226 FileToFilepathMapTy FileToFilepathMap;
228 StringRef getFullFilepath(const DIFile *File);
230 unsigned maybeRecordFile(const DIFile *F);
232 void maybeRecordLocation(const DebugLoc &DL, const MachineFunction *MF);
236 void setCurrentSubprogram(const DISubprogram *SP) {
237 CurrentSubprogram = SP;
241 /// Emit the magic version number at the start of a CodeView type or symbol
242 /// section. Appears at the front of every .debug$S or .debug$T or .debug$P
244 void emitCodeViewMagicVersion();
246 void emitTypeInformation();
248 void emitTypeGlobalHashes();
250 void emitCompilerInformation();
252 void emitInlineeLinesSubsection();
254 void emitDebugInfoForThunk(const Function *GV,
258 void emitDebugInfoForFunction(const Function *GV, FunctionInfo &FI);
260 void emitDebugInfoForGlobals();
262 void emitDebugInfoForRetainedTypes();
265 emitDebugInfoForUDTs(ArrayRef<std::pair<std::string, const DIType *>> UDTs);
267 void emitDebugInfoForGlobal(const DIGlobalVariable *DIGV,
268 const GlobalVariable *GV, MCSymbol *GVSym);
270 /// Opens a subsection of the given kind in a .debug$S codeview section.
271 /// Returns an end label for use with endCVSubsection when the subsection is
273 MCSymbol *beginCVSubsection(codeview::DebugSubsectionKind Kind);
275 void endCVSubsection(MCSymbol *EndLabel);
277 void emitInlinedCallSite(const FunctionInfo &FI, const DILocation *InlinedAt,
278 const InlineSite &Site);
280 using InlinedVariable = DbgValueHistoryMap::InlinedVariable;
282 void collectVariableInfo(const DISubprogram *SP);
284 void collectVariableInfoFromMFTable(DenseSet<InlinedVariable> &Processed);
286 // Construct the lexical block tree for a routine, pruning emptpy lexical
287 // scopes, and populate it with local variables.
288 void collectLexicalBlockInfo(SmallVectorImpl<LexicalScope *> &Scopes,
289 SmallVectorImpl<LexicalBlock *> &Blocks,
290 SmallVectorImpl<LocalVariable> &Locals);
291 void collectLexicalBlockInfo(LexicalScope &Scope,
292 SmallVectorImpl<LexicalBlock *> &ParentBlocks,
293 SmallVectorImpl<LocalVariable> &ParentLocals);
295 /// Records information about a local variable in the appropriate scope. In
296 /// particular, locals from inlined code live inside the inlining site.
297 void recordLocalVariable(LocalVariable &&Var, const LexicalScope *LS);
299 /// Emits local variables in the appropriate order.
300 void emitLocalVariableList(ArrayRef<LocalVariable> Locals);
302 /// Emits an S_LOCAL record and its associated defined ranges.
303 void emitLocalVariable(const LocalVariable &Var);
305 /// Emits a sequence of lexical block scopes and their children.
306 void emitLexicalBlockList(ArrayRef<LexicalBlock *> Blocks,
307 const FunctionInfo& FI);
309 /// Emit a lexical block scope and its children.
310 void emitLexicalBlock(const LexicalBlock &Block, const FunctionInfo& FI);
312 /// Translates the DIType to codeview if necessary and returns a type index
314 codeview::TypeIndex getTypeIndex(DITypeRef TypeRef,
315 DITypeRef ClassTyRef = DITypeRef());
317 codeview::TypeIndex getTypeIndexForReferenceTo(DITypeRef TypeRef);
319 codeview::TypeIndex getMemberFunctionType(const DISubprogram *SP,
320 const DICompositeType *Class);
322 codeview::TypeIndex getScopeIndex(const DIScope *Scope);
324 codeview::TypeIndex getVBPTypeIndex();
326 void addToUDTs(const DIType *Ty);
328 void addUDTSrcLine(const DIType *Ty, codeview::TypeIndex TI);
330 codeview::TypeIndex lowerType(const DIType *Ty, const DIType *ClassTy);
331 codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty);
332 codeview::TypeIndex lowerTypeArray(const DICompositeType *Ty);
333 codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty);
334 codeview::TypeIndex lowerTypePointer(
335 const DIDerivedType *Ty,
336 codeview::PointerOptions PO = codeview::PointerOptions::None);
337 codeview::TypeIndex lowerTypeMemberPointer(
338 const DIDerivedType *Ty,
339 codeview::PointerOptions PO = codeview::PointerOptions::None);
340 codeview::TypeIndex lowerTypeModifier(const DIDerivedType *Ty);
341 codeview::TypeIndex lowerTypeFunction(const DISubroutineType *Ty);
342 codeview::TypeIndex lowerTypeVFTableShape(const DIDerivedType *Ty);
343 codeview::TypeIndex lowerTypeMemberFunction(const DISubroutineType *Ty,
344 const DIType *ClassTy,
346 bool IsStaticMethod);
347 codeview::TypeIndex lowerTypeEnum(const DICompositeType *Ty);
348 codeview::TypeIndex lowerTypeClass(const DICompositeType *Ty);
349 codeview::TypeIndex lowerTypeUnion(const DICompositeType *Ty);
351 /// Symbol records should point to complete types, but type records should
352 /// always point to incomplete types to avoid cycles in the type graph. Only
353 /// use this entry point when generating symbol records. The complete and
354 /// incomplete type indices only differ for record types. All other types use
356 codeview::TypeIndex getCompleteTypeIndex(DITypeRef TypeRef);
358 codeview::TypeIndex lowerCompleteTypeClass(const DICompositeType *Ty);
359 codeview::TypeIndex lowerCompleteTypeUnion(const DICompositeType *Ty);
361 struct TypeLoweringScope;
363 void emitDeferredCompleteTypes();
365 void collectMemberInfo(ClassInfo &Info, const DIDerivedType *DDTy);
366 ClassInfo collectClassInfo(const DICompositeType *Ty);
368 /// Common record member lowering functionality for record types, which are
369 /// structs, classes, and unions. Returns the field list index and the member
371 std::tuple<codeview::TypeIndex, codeview::TypeIndex, unsigned, bool>
372 lowerRecordFieldList(const DICompositeType *Ty);
374 /// Inserts {{Node, ClassTy}, TI} into TypeIndices and checks for duplicates.
375 codeview::TypeIndex recordTypeIndexForDINode(const DINode *Node,
376 codeview::TypeIndex TI,
377 const DIType *ClassTy = nullptr);
379 unsigned getPointerSizeInBytes();
382 /// Gather pre-function debug information.
383 void beginFunctionImpl(const MachineFunction *MF) override;
385 /// Gather post-function debug information.
386 void endFunctionImpl(const MachineFunction *) override;
389 CodeViewDebug(AsmPrinter *AP);
391 void setSymbolSize(const MCSymbol *, uint64_t) override {}
393 /// Emit the COFF section that holds the line table information.
394 void endModule() override;
396 /// Process beginning of an instruction.
397 void beginInstruction(const MachineInstr *MI) override;
400 } // end namespace llvm
402 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H