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/TypeIndex.h"
27 #include "llvm/DebugInfo/CodeView/TypeTableBuilder.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::TypeTableBuilder 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;
100 SmallVector<LocalVariable, 1> InlinedLocals;
101 SmallVector<const DILocation *, 1> ChildSites;
102 const DISubprogram *Inlinee = nullptr;
104 /// The ID of the inline site or function used with .cv_loc. Not a type
106 unsigned SiteFuncId = 0;
109 // For each function, store a vector of labels to its instructions, as well as
110 // to the end of the function.
111 struct FunctionInfo {
112 /// Map from inlined call site to inlined instructions and child inlined
113 /// call sites. Listed in program order.
114 std::unordered_map<const DILocation *, InlineSite> InlineSites;
116 /// Ordered list of top-level inlined call sites.
117 SmallVector<const DILocation *, 1> ChildSites;
119 SmallVector<LocalVariable, 1> Locals;
121 const MCSymbol *Begin = nullptr;
122 const MCSymbol *End = nullptr;
124 unsigned LastFileId = 0;
125 bool HaveLineInfo = false;
127 FunctionInfo *CurFn = nullptr;
129 /// The set of comdat .debug$S sections that we've seen so far. Each section
130 /// must start with a magic version number that must only be emitted once.
131 /// This set tracks which sections we've already opened.
132 DenseSet<MCSectionCOFF *> ComdatDebugSections;
134 /// Switch to the appropriate .debug$S section for GVSym. If GVSym, the symbol
135 /// of an emitted global value, is in a comdat COFF section, this will switch
136 /// to a new .debug$S section in that comdat. This method ensures that the
137 /// section starts with the magic version number on first use. If GVSym is
138 /// null, uses the main .debug$S section.
139 void switchToDebugSectionForSymbol(const MCSymbol *GVSym);
141 /// The next available function index for use with our .cv_* directives. Not
142 /// to be confused with type indices for LF_FUNC_ID records.
143 unsigned NextFuncId = 0;
145 InlineSite &getInlineSite(const DILocation *InlinedAt,
146 const DISubprogram *Inlinee);
148 codeview::TypeIndex getFuncIdForSubprogram(const DISubprogram *SP);
150 static void collectInlineSiteChildren(SmallVectorImpl<unsigned> &Children,
151 const FunctionInfo &FI,
152 const InlineSite &Site);
154 /// Remember some debug info about each function. Keep it in a stable order to
155 /// emit at the end of the TU.
156 MapVector<const Function *, FunctionInfo> FnDebugInfo;
158 /// Map from DIFile to .cv_file id.
159 DenseMap<const DIFile *, unsigned> FileIdMap;
161 /// All inlined subprograms in the order they should be emitted.
162 SmallSetVector<const DISubprogram *, 4> InlinedSubprograms;
164 /// Map from a pair of DI metadata nodes and its DI type (or scope) that can
165 /// be nullptr, to CodeView type indices. Primarily indexed by
166 /// {DIType*, DIType*} and {DISubprogram*, DIType*}.
168 /// The second entry in the key is needed for methods as DISubroutineType
169 /// representing static method type are shared with non-method function type.
170 DenseMap<std::pair<const DINode *, const DIType *>, codeview::TypeIndex>
173 /// Map from DICompositeType* to complete type index. Non-record types are
174 /// always looked up in the normal TypeIndices map.
175 DenseMap<const DICompositeType *, codeview::TypeIndex> CompleteTypeIndices;
177 /// Complete record types to emit after all active type lowerings are
179 SmallVector<const DICompositeType *, 4> DeferredCompleteTypes;
181 /// Number of type lowering frames active on the stack.
182 unsigned TypeEmissionLevel = 0;
184 codeview::TypeIndex VBPType;
186 const DISubprogram *CurrentSubprogram = nullptr;
188 // The UDTs we have seen while processing types; each entry is a pair of type
189 // index and type name.
190 std::vector<std::pair<std::string, codeview::TypeIndex>> LocalUDTs,
193 using FileToFilepathMapTy = std::map<const DIFile *, std::string>;
194 FileToFilepathMapTy FileToFilepathMap;
196 StringRef getFullFilepath(const DIFile *S);
198 unsigned maybeRecordFile(const DIFile *F);
200 void maybeRecordLocation(const DebugLoc &DL, const MachineFunction *MF);
204 void setCurrentSubprogram(const DISubprogram *SP) {
205 CurrentSubprogram = SP;
209 /// Emit the magic version number at the start of a CodeView type or symbol
210 /// section. Appears at the front of every .debug$S or .debug$T section.
211 void emitCodeViewMagicVersion();
213 void emitTypeInformation();
215 void emitCompilerInformation();
217 void emitInlineeLinesSubsection();
219 void emitDebugInfoForFunction(const Function *GV, FunctionInfo &FI);
221 void emitDebugInfoForGlobals();
223 void emitDebugInfoForRetainedTypes();
225 void emitDebugInfoForUDTs(
226 ArrayRef<std::pair<std::string, codeview::TypeIndex>> UDTs);
228 void emitDebugInfoForGlobal(const DIGlobalVariable *DIGV,
229 const GlobalVariable *GV, MCSymbol *GVSym);
231 /// Opens a subsection of the given kind in a .debug$S codeview section.
232 /// Returns an end label for use with endCVSubsection when the subsection is
234 MCSymbol *beginCVSubsection(codeview::DebugSubsectionKind Kind);
236 void endCVSubsection(MCSymbol *EndLabel);
238 void emitInlinedCallSite(const FunctionInfo &FI, const DILocation *InlinedAt,
239 const InlineSite &Site);
241 using InlinedVariable = DbgValueHistoryMap::InlinedVariable;
243 void collectVariableInfo(const DISubprogram *SP);
245 void collectVariableInfoFromMFTable(DenseSet<InlinedVariable> &Processed);
247 /// Records information about a local variable in the appropriate scope. In
248 /// particular, locals from inlined code live inside the inlining site.
249 void recordLocalVariable(LocalVariable &&Var, const DILocation *Loc);
251 /// Emits local variables in the appropriate order.
252 void emitLocalVariableList(ArrayRef<LocalVariable> Locals);
254 /// Emits an S_LOCAL record and its associated defined ranges.
255 void emitLocalVariable(const LocalVariable &Var);
257 /// Translates the DIType to codeview if necessary and returns a type index
259 codeview::TypeIndex getTypeIndex(DITypeRef TypeRef,
260 DITypeRef ClassTyRef = DITypeRef());
262 codeview::TypeIndex getMemberFunctionType(const DISubprogram *SP,
263 const DICompositeType *Class);
265 codeview::TypeIndex getScopeIndex(const DIScope *Scope);
267 codeview::TypeIndex getVBPTypeIndex();
269 void addToUDTs(const DIType *Ty, codeview::TypeIndex TI);
271 codeview::TypeIndex lowerType(const DIType *Ty, const DIType *ClassTy);
272 codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty);
273 codeview::TypeIndex lowerTypeArray(const DICompositeType *Ty);
274 codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty);
275 codeview::TypeIndex lowerTypePointer(const DIDerivedType *Ty);
276 codeview::TypeIndex lowerTypeMemberPointer(const DIDerivedType *Ty);
277 codeview::TypeIndex lowerTypeModifier(const DIDerivedType *Ty);
278 codeview::TypeIndex lowerTypeFunction(const DISubroutineType *Ty);
279 codeview::TypeIndex lowerTypeVFTableShape(const DIDerivedType *Ty);
280 codeview::TypeIndex lowerTypeMemberFunction(const DISubroutineType *Ty,
281 const DIType *ClassTy,
283 codeview::TypeIndex lowerTypeEnum(const DICompositeType *Ty);
284 codeview::TypeIndex lowerTypeClass(const DICompositeType *Ty);
285 codeview::TypeIndex lowerTypeUnion(const DICompositeType *Ty);
287 /// Symbol records should point to complete types, but type records should
288 /// always point to incomplete types to avoid cycles in the type graph. Only
289 /// use this entry point when generating symbol records. The complete and
290 /// incomplete type indices only differ for record types. All other types use
292 codeview::TypeIndex getCompleteTypeIndex(DITypeRef TypeRef);
294 codeview::TypeIndex lowerCompleteTypeClass(const DICompositeType *Ty);
295 codeview::TypeIndex lowerCompleteTypeUnion(const DICompositeType *Ty);
297 struct TypeLoweringScope;
299 void emitDeferredCompleteTypes();
301 void collectMemberInfo(ClassInfo &Info, const DIDerivedType *DDTy);
302 ClassInfo collectClassInfo(const DICompositeType *Ty);
304 /// Common record member lowering functionality for record types, which are
305 /// structs, classes, and unions. Returns the field list index and the member
307 std::tuple<codeview::TypeIndex, codeview::TypeIndex, unsigned, bool>
308 lowerRecordFieldList(const DICompositeType *Ty);
310 /// Inserts {{Node, ClassTy}, TI} into TypeIndices and checks for duplicates.
311 codeview::TypeIndex recordTypeIndexForDINode(const DINode *Node,
312 codeview::TypeIndex TI,
313 const DIType *ClassTy = nullptr);
315 unsigned getPointerSizeInBytes();
318 /// \brief Gather pre-function debug information.
319 void beginFunctionImpl(const MachineFunction *MF) override;
321 /// \brief Gather post-function debug information.
322 void endFunctionImpl(const MachineFunction *) override;
325 CodeViewDebug(AsmPrinter *Asm);
327 void setSymbolSize(const MCSymbol *, uint64_t) override {}
329 /// \brief Emit the COFF section that holds the line table information.
330 void endModule() override;
332 /// \brief Process beginning of an instruction.
333 void beginInstruction(const MachineInstr *MI) override;
336 } // end namespace llvm
338 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H