1 //===- DWARFUnit.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 #ifndef LLVM_DEBUGINFO_DWARF_DWARFUNIT_H
11 #define LLVM_DEBUGINFO_DWARF_DWARFUNIT_H
13 #include "llvm/ADT/Optional.h"
14 #include "llvm/ADT/STLExtras.h"
15 #include "llvm/ADT/SmallVector.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/ADT/iterator_range.h"
18 #include "llvm/BinaryFormat/Dwarf.h"
19 #include "llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h"
20 #include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
21 #include "llvm/DebugInfo/DWARF/DWARFDebugRnglists.h"
22 #include "llvm/DebugInfo/DWARF/DWARFDie.h"
23 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
24 #include "llvm/DebugInfo/DWARF/DWARFRelocMap.h"
25 #include "llvm/DebugInfo/DWARF/DWARFSection.h"
26 #include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
27 #include "llvm/Support/DataExtractor.h"
39 class DWARFAbbreviationDeclarationSet;
41 class DWARFDebugAbbrev;
44 /// Base class describing the header of any kind of "unit." Some information
45 /// is specific to certain unit types. We separate this class out so we can
46 /// parse the header before deciding what specific kind of unit to construct.
47 class DWARFUnitHeader {
48 // Offset within section.
50 // Version, address size, and DWARF format.
51 dwarf::FormParams FormParams;
53 uint64_t AbbrOffset = 0;
55 // For DWO units only.
56 const DWARFUnitIndex::Entry *IndexEntry = nullptr;
58 // For type units only.
59 uint64_t TypeHash = 0;
60 uint32_t TypeOffset = 0;
62 // For v5 split or skeleton compile units only.
63 Optional<uint64_t> DWOId;
65 // Unit type as parsed, or derived from the section kind.
68 // Size as parsed. uint8_t for compactness.
72 /// Parse a unit header from \p debug_info starting at \p offset_ptr.
73 bool extract(DWARFContext &Context, const DWARFDataExtractor &debug_info,
74 uint32_t *offset_ptr, DWARFSectionKind Kind = DW_SECT_INFO,
75 const DWARFUnitIndex *Index = nullptr);
76 uint32_t getOffset() const { return Offset; }
77 const dwarf::FormParams &getFormParams() const { return FormParams; }
78 uint16_t getVersion() const { return FormParams.Version; }
79 dwarf::DwarfFormat getFormat() const { return FormParams.Format; }
80 uint8_t getAddressByteSize() const { return FormParams.AddrSize; }
81 uint8_t getRefAddrByteSize() const { return FormParams.getRefAddrByteSize(); }
82 uint8_t getDwarfOffsetByteSize() const {
83 return FormParams.getDwarfOffsetByteSize();
85 uint32_t getLength() const { return Length; }
86 uint64_t getAbbrOffset() const { return AbbrOffset; }
87 Optional<uint64_t> getDWOId() const { return DWOId; }
88 void setDWOId(uint64_t Id) {
89 assert((!DWOId || *DWOId == Id) && "setting DWOId to a different value");
92 const DWARFUnitIndex::Entry *getIndexEntry() const { return IndexEntry; }
93 uint64_t getTypeHash() const { return TypeHash; }
94 uint32_t getTypeOffset() const { return TypeOffset; }
95 uint8_t getUnitType() const { return UnitType; }
96 bool isTypeUnit() const {
97 return UnitType == dwarf::DW_UT_type || UnitType == dwarf::DW_UT_split_type;
99 uint8_t getSize() const { return Size; }
100 // FIXME: Support DWARF64.
101 uint32_t getNextUnitOffset() const { return Offset + Length + 4; }
104 const DWARFUnitIndex &getDWARFUnitIndex(DWARFContext &Context,
105 DWARFSectionKind Kind);
107 /// Describe a collection of units. Intended to hold all units either from
108 /// .debug_info and .debug_types, or from .debug_info.dwo and .debug_types.dwo.
109 class DWARFUnitVector final : public SmallVector<std::unique_ptr<DWARFUnit>, 1> {
110 std::function<std::unique_ptr<DWARFUnit>(uint32_t, DWARFSectionKind,
111 const DWARFSection *)>
113 int NumInfoUnits = -1;
116 using UnitVector = SmallVectorImpl<std::unique_ptr<DWARFUnit>>;
117 using iterator = typename UnitVector::iterator;
118 using iterator_range = llvm::iterator_range<typename UnitVector::iterator>;
120 DWARFUnit *getUnitForOffset(uint32_t Offset) const;
121 DWARFUnit *getUnitForIndexEntry(const DWARFUnitIndex::Entry &E);
123 /// Read units from a .debug_info or .debug_types section. Calls made
124 /// before finishedInfoUnits() are assumed to be for .debug_info sections,
125 /// calls after finishedInfoUnits() are for .debug_types sections. Caller
126 /// must not mix calls to addUnitsForSection and addUnitsForDWOSection.
127 void addUnitsForSection(DWARFContext &C, const DWARFSection &Section,
128 DWARFSectionKind SectionKind);
129 /// Read units from a .debug_info.dwo or .debug_types.dwo section. Calls
130 /// made before finishedInfoUnits() are assumed to be for .debug_info.dwo
131 /// sections, calls after finishedInfoUnits() are for .debug_types.dwo
132 /// sections. Caller must not mix calls to addUnitsForSection and
133 /// addUnitsForDWOSection.
134 void addUnitsForDWOSection(DWARFContext &C, const DWARFSection &DWOSection,
135 DWARFSectionKind SectionKind, bool Lazy = false);
137 /// Add an existing DWARFUnit to this UnitVector. This is used by the DWARF
138 /// verifier to process unit separately.
139 DWARFUnit *addUnit(std::unique_ptr<DWARFUnit> Unit);
141 /// Returns number of all units held by this instance.
142 unsigned getNumUnits() const { return size(); }
143 /// Returns number of units from all .debug_info[.dwo] sections.
144 unsigned getNumInfoUnits() const {
145 return NumInfoUnits == -1 ? size() : NumInfoUnits;
147 /// Returns number of units from all .debug_types[.dwo] sections.
148 unsigned getNumTypesUnits() const { return size() - NumInfoUnits; }
149 /// Indicate that parsing .debug_info[.dwo] is done, and remaining units
150 /// will be from .debug_types[.dwo].
151 void finishedInfoUnits() { NumInfoUnits = size(); }
154 void addUnitsImpl(DWARFContext &Context, const DWARFObject &Obj,
155 const DWARFSection &Section, const DWARFDebugAbbrev *DA,
156 const DWARFSection *RS, const DWARFSection *LocSection,
157 StringRef SS, const DWARFSection &SOS,
158 const DWARFSection *AOS, const DWARFSection &LS, bool LE,
159 bool IsDWO, bool Lazy, DWARFSectionKind SectionKind);
162 /// Represents base address of the CU.
163 /// Represents a unit's contribution to the string offsets table.
164 struct StrOffsetsContributionDescriptor {
166 /// The contribution size not including the header.
168 /// Format and version.
169 dwarf::FormParams FormParams = {0, 0, dwarf::DwarfFormat::DWARF32};
171 StrOffsetsContributionDescriptor(uint64_t Base, uint64_t Size,
172 uint8_t Version, dwarf::DwarfFormat Format)
173 : Base(Base), Size(Size), FormParams({Version, 0, Format}) {}
175 uint8_t getVersion() const { return FormParams.Version; }
176 dwarf::DwarfFormat getFormat() const { return FormParams.Format; }
177 uint8_t getDwarfOffsetByteSize() const {
178 return FormParams.getDwarfOffsetByteSize();
180 /// Determine whether a contribution to the string offsets table is
181 /// consistent with the relevant section size and that its length is
182 /// a multiple of the size of one of its entries.
183 Optional<StrOffsetsContributionDescriptor>
184 validateContributionSize(DWARFDataExtractor &DA);
188 DWARFContext &Context;
189 /// Section containing this DWARFUnit.
190 const DWARFSection &InfoSection;
192 DWARFUnitHeader Header;
193 const DWARFDebugAbbrev *Abbrev;
194 const DWARFSection *RangeSection;
195 uint32_t RangeSectionBase;
196 /// We either keep track of the location list section or its data, depending
197 /// on whether we are handling a split DWARF section or not.
199 const DWARFSection *LocSection;
200 StringRef LocSectionData;
202 const DWARFSection &LineSection;
203 StringRef StringSection;
204 const DWARFSection &StringOffsetSection;
205 const DWARFSection *AddrOffsetSection;
206 uint32_t AddrOffsetSectionBase = 0;
209 const DWARFUnitVector &UnitVector;
211 /// Start, length, and DWARF format of the unit's contribution to the string
212 /// offsets table (DWARF v5).
213 Optional<StrOffsetsContributionDescriptor> StringOffsetsTableContribution;
215 /// A table of range lists (DWARF v5 and later).
216 Optional<DWARFDebugRnglistTable> RngListTable;
218 mutable const DWARFAbbreviationDeclarationSet *Abbrevs;
219 llvm::Optional<SectionedAddress> BaseAddr;
220 /// The compile unit debug information entry items.
221 std::vector<DWARFDebugInfoEntry> DieArray;
223 /// Map from range's start address to end address and corresponding DIE.
224 /// IntervalMap does not support range removal, as a result, we use the
225 /// std::map::upper_bound for address range lookup.
226 std::map<uint64_t, std::pair<uint64_t, DWARFDie>> AddrDieMap;
228 using die_iterator_range =
229 iterator_range<std::vector<DWARFDebugInfoEntry>::iterator>;
231 std::shared_ptr<DWARFUnit> DWO;
233 uint32_t getDIEIndex(const DWARFDebugInfoEntry *Die) {
234 auto First = DieArray.data();
235 assert(Die >= First && Die < First + DieArray.size());
240 const DWARFUnitHeader &getHeader() const { return Header; }
242 /// Size in bytes of the parsed unit header.
243 uint32_t getHeaderSize() const { return Header.getSize(); }
245 /// Find the unit's contribution to the string offsets table and determine its
246 /// length and form. The given offset is expected to be derived from the unit
247 /// DIE's DW_AT_str_offsets_base attribute.
248 Optional<StrOffsetsContributionDescriptor>
249 determineStringOffsetsTableContribution(DWARFDataExtractor &DA);
251 /// Find the unit's contribution to the string offsets table and determine its
252 /// length and form. The given offset is expected to be 0 in a dwo file or,
253 /// in a dwp file, the start of the unit's contribution to the string offsets
254 /// table section (as determined by the index table).
255 Optional<StrOffsetsContributionDescriptor>
256 determineStringOffsetsTableContributionDWO(DWARFDataExtractor &DA);
259 DWARFUnit(DWARFContext &Context, const DWARFSection &Section,
260 const DWARFUnitHeader &Header, const DWARFDebugAbbrev *DA,
261 const DWARFSection *RS, const DWARFSection *LocSection,
262 StringRef SS, const DWARFSection &SOS, const DWARFSection *AOS,
263 const DWARFSection &LS, bool LE, bool IsDWO,
264 const DWARFUnitVector &UnitVector);
266 virtual ~DWARFUnit();
268 bool isDWOUnit() const { return IsDWO; }
269 DWARFContext& getContext() const { return Context; }
270 const DWARFSection &getInfoSection() const { return InfoSection; }
271 const DWARFSection *getLocSection() const { return LocSection; }
272 StringRef getLocSectionData() const { return LocSectionData; }
273 uint32_t getOffset() const { return Header.getOffset(); }
274 const dwarf::FormParams &getFormParams() const {
275 return Header.getFormParams();
277 uint16_t getVersion() const { return Header.getVersion(); }
278 uint8_t getAddressByteSize() const { return Header.getAddressByteSize(); }
279 uint8_t getRefAddrByteSize() const { return Header.getRefAddrByteSize(); }
280 uint8_t getDwarfOffsetByteSize() const {
281 return Header.getDwarfOffsetByteSize();
283 uint32_t getLength() const { return Header.getLength(); }
284 uint8_t getUnitType() const { return Header.getUnitType(); }
285 bool isTypeUnit() const { return Header.isTypeUnit(); }
286 uint32_t getNextUnitOffset() const { return Header.getNextUnitOffset(); }
287 const DWARFSection &getLineSection() const { return LineSection; }
288 StringRef getStringSection() const { return StringSection; }
289 const DWARFSection &getStringOffsetSection() const {
290 return StringOffsetSection;
293 void setAddrOffsetSection(const DWARFSection *AOS, uint32_t Base) {
294 AddrOffsetSection = AOS;
295 AddrOffsetSectionBase = Base;
298 /// Recursively update address to Die map.
299 void updateAddressDieMap(DWARFDie Die);
301 void setRangesSection(const DWARFSection *RS, uint32_t Base) {
303 RangeSectionBase = Base;
306 Optional<SectionedAddress> getAddrOffsetSectionItem(uint32_t Index) const;
307 Optional<uint64_t> getStringOffsetSectionItem(uint32_t Index) const;
309 DWARFDataExtractor getDebugInfoExtractor() const;
311 DataExtractor getStringExtractor() const {
312 return DataExtractor(StringSection, false, 0);
315 /// Extract the range list referenced by this compile unit from the
316 /// .debug_ranges section. If the extraction is unsuccessful, an error
317 /// is returned. Successful extraction requires that the compile unit
318 /// has already been extracted.
319 Error extractRangeList(uint32_t RangeListOffset,
320 DWARFDebugRangeList &RangeList) const;
323 const Optional<StrOffsetsContributionDescriptor> &
324 getStringOffsetsTableContribution() const {
325 return StringOffsetsTableContribution;
328 uint8_t getDwarfStringOffsetsByteSize() const {
329 assert(StringOffsetsTableContribution);
330 return StringOffsetsTableContribution->getDwarfOffsetByteSize();
333 uint64_t getStringOffsetsBase() const {
334 assert(StringOffsetsTableContribution);
335 return StringOffsetsTableContribution->Base;
338 const DWARFAbbreviationDeclarationSet *getAbbreviations() const;
340 static bool isMatchingUnitTypeAndTag(uint8_t UnitType, dwarf::Tag Tag) {
342 case dwarf::DW_UT_compile:
343 return Tag == dwarf::DW_TAG_compile_unit;
344 case dwarf::DW_UT_type:
345 return Tag == dwarf::DW_TAG_type_unit;
346 case dwarf::DW_UT_partial:
347 return Tag == dwarf::DW_TAG_partial_unit;
348 case dwarf::DW_UT_skeleton:
349 return Tag == dwarf::DW_TAG_skeleton_unit;
350 case dwarf::DW_UT_split_compile:
351 case dwarf::DW_UT_split_type:
352 return dwarf::isUnitType(Tag);
357 /// Return the number of bytes for the header of a unit of
360 /// This function must be called with a valid unit type which in
361 /// DWARF5 is defined as one of the following six types.
362 static uint32_t getDWARF5HeaderSize(uint8_t UnitType) {
364 case dwarf::DW_UT_compile:
365 case dwarf::DW_UT_partial:
367 case dwarf::DW_UT_skeleton:
368 case dwarf::DW_UT_split_compile:
370 case dwarf::DW_UT_type:
371 case dwarf::DW_UT_split_type:
374 llvm_unreachable("Invalid UnitType.");
377 llvm::Optional<SectionedAddress> getBaseAddress();
379 DWARFDie getUnitDIE(bool ExtractUnitDIEOnly = true) {
380 extractDIEsIfNeeded(ExtractUnitDIEOnly);
381 if (DieArray.empty())
383 return DWARFDie(this, &DieArray[0]);
386 const char *getCompilationDir();
387 Optional<uint64_t> getDWOId() {
388 extractDIEsIfNeeded(/*CUDieOnly*/ true);
389 return getHeader().getDWOId();
391 void setDWOId(uint64_t NewID) { Header.setDWOId(NewID); }
393 /// Return a vector of address ranges resulting from a (possibly encoded)
394 /// range list starting at a given offset in the appropriate ranges section.
395 Expected<DWARFAddressRangesVector> findRnglistFromOffset(uint32_t Offset);
397 /// Return a vector of address ranges retrieved from an encoded range
398 /// list whose offset is found via a table lookup given an index (DWARF v5
400 Expected<DWARFAddressRangesVector> findRnglistFromIndex(uint32_t Index);
402 /// Return a rangelist's offset based on an index. The index designates
403 /// an entry in the rangelist table's offset array and is supplied by
404 /// DW_FORM_rnglistx.
405 Optional<uint32_t> getRnglistOffset(uint32_t Index) {
407 return RngListTable->getOffsetEntry(Index);
411 void collectAddressRanges(DWARFAddressRangesVector &CURanges);
413 /// Returns subprogram DIE with address range encompassing the provided
414 /// address. The pointer is alive as long as parsed compile unit DIEs are not
416 DWARFDie getSubroutineForAddress(uint64_t Address);
418 /// getInlinedChainForAddress - fetches inlined chain for a given address.
419 /// Returns empty chain if there is no subprogram containing address. The
420 /// chain is valid as long as parsed compile unit DIEs are not cleared.
421 void getInlinedChainForAddress(uint64_t Address,
422 SmallVectorImpl<DWARFDie> &InlinedChain);
424 /// Return the DWARFUnitVector containing this unit.
425 const DWARFUnitVector &getUnitVector() const { return UnitVector; }
427 /// Returns the number of DIEs in the unit. Parses the unit
429 unsigned getNumDIEs() {
430 extractDIEsIfNeeded(false);
431 return DieArray.size();
434 /// Return the index of a DIE inside the unit's DIE vector.
436 /// It is illegal to call this method with a DIE that hasn't be
437 /// created by this unit. In other word, it's illegal to call this
438 /// method on a DIE that isn't accessible by following
439 /// children/sibling links starting from this unit's getUnitDIE().
440 uint32_t getDIEIndex(const DWARFDie &D) {
441 return getDIEIndex(D.getDebugInfoEntry());
444 /// Return the DIE object at the given index.
445 DWARFDie getDIEAtIndex(unsigned Index) {
446 assert(Index < DieArray.size());
447 return DWARFDie(this, &DieArray[Index]);
450 DWARFDie getParent(const DWARFDebugInfoEntry *Die);
451 DWARFDie getSibling(const DWARFDebugInfoEntry *Die);
452 DWARFDie getPreviousSibling(const DWARFDebugInfoEntry *Die);
453 DWARFDie getFirstChild(const DWARFDebugInfoEntry *Die);
454 DWARFDie getLastChild(const DWARFDebugInfoEntry *Die);
456 /// Return the DIE object for a given offset inside the
457 /// unit's DIE vector.
459 /// The unit needs to have its DIEs extracted for this method to work.
460 DWARFDie getDIEForOffset(uint32_t Offset) {
461 extractDIEsIfNeeded(false);
462 assert(!DieArray.empty());
463 auto it = std::lower_bound(
464 DieArray.begin(), DieArray.end(), Offset,
465 [](const DWARFDebugInfoEntry &LHS, uint32_t Offset) {
466 return LHS.getOffset() < Offset;
468 if (it != DieArray.end() && it->getOffset() == Offset)
469 return DWARFDie(this, &*it);
473 uint32_t getLineTableOffset() const {
474 if (auto IndexEntry = Header.getIndexEntry())
475 if (const auto *Contrib = IndexEntry->getOffset(DW_SECT_LINE))
476 return Contrib->Offset;
480 die_iterator_range dies() {
481 extractDIEsIfNeeded(false);
482 return die_iterator_range(DieArray.begin(), DieArray.end());
485 virtual void dump(raw_ostream &OS, DIDumpOptions DumpOpts) = 0;
487 /// Size in bytes of the .debug_info data associated with this compile unit.
488 size_t getDebugInfoSize() const {
489 return Header.getLength() + 4 - getHeaderSize();
492 /// extractDIEsIfNeeded - Parses a compile unit and indexes its DIEs if it
493 /// hasn't already been done. Returns the number of DIEs parsed at this call.
494 size_t extractDIEsIfNeeded(bool CUDieOnly);
496 /// extractDIEsToVector - Appends all parsed DIEs to a vector.
497 void extractDIEsToVector(bool AppendCUDie, bool AppendNonCUDIEs,
498 std::vector<DWARFDebugInfoEntry> &DIEs) const;
500 /// clearDIEs - Clear parsed DIEs to keep memory usage low.
501 void clearDIEs(bool KeepCUDie);
503 /// parseDWO - Parses .dwo file for current compile unit. Returns true if
504 /// it was actually constructed.
508 } // end namespace llvm
510 #endif // LLVM_DEBUGINFO_DWARF_DWARFUNIT_H