1 //===-- llvm/CodeGen/DwarfUnit.h - Dwarf Compile Unit ---*- 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 dwarf compile unit.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DWARFUNIT_H
15 #define LLVM_LIB_CODEGEN_ASMPRINTER_DWARFUNIT_H
17 #include "DwarfDebug.h"
18 #include "llvm/ADT/DenseMap.h"
19 #include "llvm/ADT/Optional.h"
20 #include "llvm/ADT/StringMap.h"
21 #include "llvm/CodeGen/AsmPrinter.h"
22 #include "llvm/CodeGen/DIE.h"
23 #include "llvm/IR/DIBuilder.h"
24 #include "llvm/IR/DebugInfo.h"
25 #include "llvm/MC/MCDwarf.h"
26 #include "llvm/MC/MCExpr.h"
27 #include "llvm/MC/MCSection.h"
31 class MachineLocation;
36 class DwarfCompileUnit;
38 // Data structure to hold a range for range lists.
41 RangeSpan(MCSymbol *S, MCSymbol *E) : Start(S), End(E) {}
42 const MCSymbol *getStart() const { return Start; }
43 const MCSymbol *getEnd() const { return End; }
44 void setEnd(const MCSymbol *E) { End = E; }
47 const MCSymbol *Start, *End;
52 // Index for locating within the debug_range section this particular span.
55 SmallVector<RangeSpan, 2> Ranges;
58 RangeSpanList(MCSymbol *Sym, SmallVector<RangeSpan, 2> Ranges)
59 : RangeSym(Sym), Ranges(std::move(Ranges)) {}
60 MCSymbol *getSym() const { return RangeSym; }
61 const SmallVectorImpl<RangeSpan> &getRanges() const { return Ranges; }
62 void addRange(RangeSpan Range) { Ranges.push_back(Range); }
65 //===----------------------------------------------------------------------===//
66 /// This dwarf writer support class manages information associated with a
70 /// A numeric ID unique among all CUs in the module
73 /// MDNode for the compile unit.
74 const DICompileUnit *CUNode;
76 // All DIEValues are allocated through this allocator.
77 BumpPtrAllocator DIEValueAllocator;
79 /// Unit debug information entry.
82 /// Offset of the UnitDie from beginning of debug info section.
83 unsigned DebugInfoOffset;
85 /// Target of Dwarf emission.
88 // Holders for some common dwarf information.
92 /// An anonymous type for index type. Owned by UnitDie.
95 /// Tracks the mapping of unit level debug information variables to debug
96 /// information entries.
97 DenseMap<const MDNode *, DIE *> MDNodeToDieMap;
99 /// A list of all the DIEBlocks in use.
100 std::vector<DIEBlock *> DIEBlocks;
102 /// A list of all the DIELocs in use.
103 std::vector<DIELoc *> DIELocs;
105 /// This map is used to keep track of subprogram DIEs that need
106 /// DW_AT_containing_type attribute. This attribute points to a DIE that
107 /// corresponds to the MDNode mapped with the subprogram DIE.
108 DenseMap<DIE *, const DINode *> ContainingTypeMap;
110 /// The section this unit will be emitted in.
113 DwarfUnit(unsigned UID, dwarf::Tag, const DICompileUnit *CU, AsmPrinter *A,
114 DwarfDebug *DW, DwarfFile *DWU);
116 bool applySubprogramDefinitionAttributes(const DISubprogram *SP, DIE &SPDie);
119 virtual ~DwarfUnit();
121 void initSection(MCSection *Section);
123 MCSection *getSection() const {
129 AsmPrinter* getAsmPrinter() const { return Asm; }
130 unsigned getUniqueID() const { return UniqueID; }
131 uint16_t getLanguage() const { return CUNode->getSourceLanguage(); }
132 const DICompileUnit *getCUNode() const { return CUNode; }
133 DIE &getUnitDie() { return UnitDie; }
135 unsigned getDebugInfoOffset() const { return DebugInfoOffset; }
136 void setDebugInfoOffset(unsigned DbgInfoOff) { DebugInfoOffset = DbgInfoOff; }
138 /// Return true if this compile unit has something to write out.
139 bool hasContent() const { return UnitDie.hasChildren(); }
141 /// Get string containing language specific context for a global name.
143 /// Walks the metadata parent chain in a language specific manner (using the
144 /// compile unit language) and returns it as a string. This is done at the
145 /// metadata level because DIEs may not currently have been added to the
146 /// parent context and walking the DIEs looking for names is more expensive
147 /// than walking the metadata.
148 std::string getParentContextString(const DIScope *Context) const;
150 /// Add a new global name to the compile unit.
151 virtual void addGlobalName(StringRef Name, DIE &Die, const DIScope *Context) {
154 /// Add a new global type to the compile unit.
155 virtual void addGlobalType(const DIType *Ty, const DIE &Die,
156 const DIScope *Context) {}
158 /// Returns the DIE map slot for the specified debug variable.
160 /// We delegate the request to DwarfDebug when the MDNode can be part of the
161 /// type system, since DIEs for the type system can be shared across CUs and
162 /// the mappings are kept in DwarfDebug.
163 DIE *getDIE(const DINode *D) const;
165 /// Returns a fresh newly allocated DIELoc.
166 DIELoc *getDIELoc() { return new (DIEValueAllocator) DIELoc; }
168 /// Insert DIE into the map.
170 /// We delegate the request to DwarfDebug when the MDNode can be part of the
171 /// type system, since DIEs for the type system can be shared across CUs and
172 /// the mappings are kept in DwarfDebug.
173 void insertDIE(const DINode *Desc, DIE *D);
175 /// Add a flag that is true to the DIE.
176 void addFlag(DIE &Die, dwarf::Attribute Attribute);
178 /// Add an unsigned integer attribute data and value.
179 void addUInt(DIEValueList &Die, dwarf::Attribute Attribute,
180 Optional<dwarf::Form> Form, uint64_t Integer);
182 void addUInt(DIEValueList &Block, dwarf::Form Form, uint64_t Integer);
184 /// Add an signed integer attribute data and value.
185 void addSInt(DIEValueList &Die, dwarf::Attribute Attribute,
186 Optional<dwarf::Form> Form, int64_t Integer);
188 void addSInt(DIELoc &Die, Optional<dwarf::Form> Form, int64_t Integer);
190 /// Add a string attribute data and value.
192 /// We always emit a reference to the string pool instead of immediate
193 /// strings so that DIEs have more predictable sizes. In the case of split
194 /// dwarf we emit an index into another table which gets us the static offset
195 /// into the string table.
196 void addString(DIE &Die, dwarf::Attribute Attribute, StringRef Str);
198 /// Add a Dwarf label attribute data and value.
199 DIEValueList::value_iterator addLabel(DIEValueList &Die,
200 dwarf::Attribute Attribute,
202 const MCSymbol *Label);
204 void addLabel(DIELoc &Die, dwarf::Form Form, const MCSymbol *Label);
206 /// Add an offset into a section attribute data and value.
207 void addSectionOffset(DIE &Die, dwarf::Attribute Attribute, uint64_t Integer);
209 /// Add a dwarf op address data and value using the form given and an
210 /// op of either DW_FORM_addr or DW_FORM_GNU_addr_index.
211 void addOpAddress(DIELoc &Die, const MCSymbol *Label);
213 /// Add a label delta attribute data and value.
214 void addLabelDelta(DIE &Die, dwarf::Attribute Attribute, const MCSymbol *Hi,
217 /// Add a DIE attribute data and value.
218 void addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIE &Entry);
220 /// Add a DIE attribute data and value.
221 void addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIEEntry Entry);
223 /// Add a type's DW_AT_signature and set the declaration flag.
224 void addDIETypeSignature(DIE &Die, const DwarfTypeUnit &Type);
225 /// Add an attribute containing the type signature for a unique identifier.
226 void addDIETypeSignature(DIE &Die, dwarf::Attribute Attribute,
227 StringRef Identifier);
230 void addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Block);
233 void addBlock(DIE &Die, dwarf::Attribute Attribute, DIEBlock *Block);
235 /// Add location information to specified debug information entry.
236 void addSourceLine(DIE &Die, unsigned Line, StringRef File,
237 StringRef Directory);
238 void addSourceLine(DIE &Die, const DILocalVariable *V);
239 void addSourceLine(DIE &Die, const DIGlobalVariable *G);
240 void addSourceLine(DIE &Die, const DISubprogram *SP);
241 void addSourceLine(DIE &Die, const DIType *Ty);
242 void addSourceLine(DIE &Die, const DINamespace *NS);
243 void addSourceLine(DIE &Die, const DIObjCProperty *Ty);
245 /// Add constant value entry in variable DIE.
246 void addConstantValue(DIE &Die, const MachineOperand &MO, const DIType *Ty);
247 void addConstantValue(DIE &Die, const ConstantInt *CI, const DIType *Ty);
248 void addConstantValue(DIE &Die, const APInt &Val, const DIType *Ty);
249 void addConstantValue(DIE &Die, const APInt &Val, bool Unsigned);
250 void addConstantValue(DIE &Die, bool Unsigned, uint64_t Val);
252 /// Add constant value entry in variable DIE.
253 void addConstantFPValue(DIE &Die, const MachineOperand &MO);
254 void addConstantFPValue(DIE &Die, const ConstantFP *CFP);
256 /// Add a linkage name, if it isn't empty.
257 void addLinkageName(DIE &Die, StringRef LinkageName);
259 /// Add template parameters in buffer.
260 void addTemplateParams(DIE &Buffer, DINodeArray TParams);
262 /// Add register operand.
263 /// \returns false if the register does not exist, e.g., because it was never
265 bool addRegisterOpPiece(DIELoc &TheDie, unsigned Reg,
266 unsigned SizeInBits = 0, unsigned OffsetInBits = 0);
268 /// Add register offset.
269 /// \returns false if the register does not exist, e.g., because it was never
271 bool addRegisterOffset(DIELoc &TheDie, unsigned Reg, int64_t Offset);
273 // FIXME: Should be reformulated in terms of addComplexAddress.
274 /// Start with the address based on the location provided, and generate the
275 /// DWARF information necessary to find the actual Block variable (navigating
276 /// the Block struct) based on the starting location. Add the DWARF
277 /// information to the die. Obsolete, please use addComplexAddress instead.
278 void addBlockByrefAddress(const DbgVariable &DV, DIE &Die,
279 dwarf::Attribute Attribute,
280 const MachineLocation &Location);
282 /// Add a new type attribute to the specified entity.
284 /// This takes and attribute parameter because DW_AT_friend attributes are
285 /// also type references.
286 void addType(DIE &Entity, const DIType *Ty,
287 dwarf::Attribute Attribute = dwarf::DW_AT_type);
289 DIE *getOrCreateNameSpace(const DINamespace *NS);
290 DIE *getOrCreateModule(const DIModule *M);
291 DIE *getOrCreateSubprogramDIE(const DISubprogram *SP, bool Minimal = false);
293 void applySubprogramAttributes(const DISubprogram *SP, DIE &SPDie,
294 bool Minimal = false);
296 /// Find existing DIE or create new DIE for the given type.
297 DIE *getOrCreateTypeDIE(const MDNode *N);
299 /// Get context owner's DIE.
300 DIE *createTypeDIE(const DICompositeType *Ty);
302 /// Get context owner's DIE.
303 DIE *getOrCreateContextDIE(const DIScope *Context);
305 /// Construct DIEs for types that contain vtables.
306 void constructContainingTypeDIEs();
308 /// Construct function argument DIEs.
309 void constructSubprogramArguments(DIE &Buffer, DITypeRefArray Args);
311 /// Create a DIE with the given Tag, add the DIE to its parent, and
312 /// call insertDIE if MD is not null.
313 DIE &createAndAddDIE(unsigned Tag, DIE &Parent, const DINode *N = nullptr);
315 /// Compute the size of a header for this unit, not including the initial
317 virtual unsigned getHeaderSize() const {
318 return sizeof(int16_t) + // DWARF version number
319 sizeof(int32_t) + // Offset Into Abbrev. Section
320 sizeof(int8_t); // Pointer Size (in bytes)
323 /// Emit the header for this unit, not including the initial length field.
324 virtual void emitHeader(bool UseOffsets);
326 virtual DwarfCompileUnit &getCU() = 0;
328 void constructTypeDIE(DIE &Buffer, const DICompositeType *CTy);
331 /// Create new static data member DIE.
332 DIE *getOrCreateStaticMemberDIE(const DIDerivedType *DT);
334 /// Look up the source ID with the given directory and source file names. If
335 /// none currently exists, create a new ID and insert it in the line table.
336 virtual unsigned getOrCreateSourceID(StringRef File, StringRef Directory) = 0;
338 /// Look in the DwarfDebug map for the MDNode that corresponds to the
340 template <typename T> T *resolve(TypedDINodeRef<T> Ref) const {
341 return DD->resolve(Ref);
345 void constructTypeDIE(DIE &Buffer, const DIBasicType *BTy);
346 void constructTypeDIE(DIE &Buffer, const DIDerivedType *DTy);
347 void constructTypeDIE(DIE &Buffer, const DISubroutineType *DTy);
348 void constructSubrangeDIE(DIE &Buffer, const DISubrange *SR, DIE *IndexTy);
349 void constructArrayTypeDIE(DIE &Buffer, const DICompositeType *CTy);
350 void constructEnumTypeDIE(DIE &Buffer, const DICompositeType *CTy);
351 void constructMemberDIE(DIE &Buffer, const DIDerivedType *DT);
352 void constructTemplateTypeParameterDIE(DIE &Buffer,
353 const DITemplateTypeParameter *TP);
354 void constructTemplateValueParameterDIE(DIE &Buffer,
355 const DITemplateValueParameter *TVP);
357 /// Return the default lower bound for an array.
359 /// If the DWARF version doesn't handle the language, return -1.
360 int64_t getDefaultLowerBound() const;
362 /// Get an anonymous type for index type.
363 DIE *getIndexTyDie();
365 /// Set D as anonymous type for index which can be reused later.
366 void setIndexTyDie(DIE *D) { IndexTyDie = D; }
368 /// If this is a named finished type then include it in the list of types for
369 /// the accelerator tables.
370 void updateAcceleratorTables(const DIScope *Context, const DIType *Ty,
373 virtual bool isDwoUnit() const = 0;
376 class DwarfTypeUnit : public DwarfUnit {
377 uint64_t TypeSignature;
379 DwarfCompileUnit &CU;
380 MCDwarfDwoLineTable *SplitLineTable;
382 unsigned getOrCreateSourceID(StringRef File, StringRef Directory) override;
383 bool isDwoUnit() const override;
386 DwarfTypeUnit(unsigned UID, DwarfCompileUnit &CU, AsmPrinter *A,
387 DwarfDebug *DW, DwarfFile *DWU,
388 MCDwarfDwoLineTable *SplitLineTable = nullptr);
390 void setTypeSignature(uint64_t Signature) { TypeSignature = Signature; }
391 uint64_t getTypeSignature() const { return TypeSignature; }
392 void setType(const DIE *Ty) { this->Ty = Ty; }
394 /// Emit the header for this unit, not including the initial length field.
395 void emitHeader(bool UseOffsets) override;
396 unsigned getHeaderSize() const override {
397 return DwarfUnit::getHeaderSize() + sizeof(uint64_t) + // Type Signature
398 sizeof(uint32_t); // Type DIE Offset
400 DwarfCompileUnit &getCU() override { return CU; }
402 } // end llvm namespace