1 //===- DWARFDebugLine.h -----------------------------------------*- C++ -*-===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 #ifndef LLVM_DEBUGINFO_DWARFDEBUGLINE_H
10 #define LLVM_DEBUGINFO_DWARFDEBUGLINE_H
12 #include "llvm/ADT/Optional.h"
13 #include "llvm/ADT/StringRef.h"
14 #include "llvm/DebugInfo/DIContext.h"
15 #include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
16 #include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
17 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
18 #include "llvm/DebugInfo/DWARF/DWARFRelocMap.h"
19 #include "llvm/DebugInfo/DWARF/DWARFTypeUnit.h"
20 #include "llvm/Support/MD5.h"
31 class DWARFDebugLine {
33 struct FileNameEntry {
34 FileNameEntry() = default;
40 MD5::MD5Result Checksum;
41 DWARFFormValue Source;
44 /// Tracks which optional content types are present in a DWARF file name
46 struct ContentTypeTracker {
47 ContentTypeTracker() = default;
49 /// Whether filename entries provide a modification timestamp.
50 bool HasModTime = false;
51 /// Whether filename entries provide a file size.
52 bool HasLength = false;
53 /// For v5, whether filename entries provide an MD5 checksum.
55 /// For v5, whether filename entries provide source text.
56 bool HasSource = false;
58 /// Update tracked content types with \p ContentType.
59 void trackContentType(dwarf::LineNumberEntryFormat ContentType);
65 /// The size in bytes of the statement information for this compilation unit
66 /// (not including the total_length field itself).
68 /// Version, address size (starting in v5), and DWARF32/64 format; these
69 /// parameters affect interpretation of forms (used in the directory and
70 /// file tables starting with v5).
71 dwarf::FormParams FormParams;
72 /// The number of bytes following the prologue_length field to the beginning
73 /// of the first byte of the statement program itself.
74 uint64_t PrologueLength;
75 /// In v5, size in bytes of a segment selector.
76 uint8_t SegSelectorSize;
77 /// The size in bytes of the smallest target machine instruction. Statement
78 /// program opcodes that alter the address register first multiply their
79 /// operands by this value.
80 uint8_t MinInstLength;
81 /// The maximum number of individual operations that may be encoded in an
83 uint8_t MaxOpsPerInst;
84 /// The initial value of theis_stmtregister.
85 uint8_t DefaultIsStmt;
86 /// This parameter affects the meaning of the special opcodes. See below.
88 /// This parameter affects the meaning of the special opcodes. See below.
90 /// The number assigned to the first special opcode.
92 /// This tracks which optional file format content types are present.
93 ContentTypeTracker ContentTypes;
94 std::vector<uint8_t> StandardOpcodeLengths;
95 std::vector<DWARFFormValue> IncludeDirectories;
96 std::vector<FileNameEntry> FileNames;
98 const dwarf::FormParams getFormParams() const { return FormParams; }
99 uint16_t getVersion() const { return FormParams.Version; }
100 uint8_t getAddressSize() const { return FormParams.AddrSize; }
101 bool isDWARF64() const { return FormParams.Format == dwarf::DWARF64; }
103 uint32_t sizeofTotalLength() const { return isDWARF64() ? 12 : 4; }
105 uint32_t sizeofPrologueLength() const { return isDWARF64() ? 8 : 4; }
107 bool totalLengthIsValid() const;
109 /// Length of the prologue in bytes.
110 uint32_t getLength() const {
111 return PrologueLength + sizeofTotalLength() + sizeof(getVersion()) +
112 sizeofPrologueLength();
115 /// Length of the line table data in bytes (not including the prologue).
116 uint32_t getStatementTableLength() const {
117 return TotalLength + sizeofTotalLength() - getLength();
120 int32_t getMaxLineIncrementForSpecialOpcode() const {
121 return LineBase + (int8_t)LineRange - 1;
124 /// Get DWARF-version aware access to the file name entry at the provided
126 const llvm::DWARFDebugLine::FileNameEntry &
127 getFileNameEntry(uint64_t Index) const;
129 bool hasFileAtIndex(uint64_t FileIndex) const;
131 bool getFileNameByIndex(uint64_t FileIndex, StringRef CompDir,
132 DILineInfoSpecifier::FileLineInfoKind Kind,
133 std::string &Result) const;
136 void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
137 Error parse(const DWARFDataExtractor &DebugLineData, uint32_t *OffsetPtr,
138 const DWARFContext &Ctx, const DWARFUnit *U = nullptr);
141 /// Standard .debug_line state machine structure.
143 explicit Row(bool DefaultIsStmt = false);
145 /// Called after a row is appended to the matrix.
147 void reset(bool DefaultIsStmt);
148 void dump(raw_ostream &OS) const;
150 static void dumpTableHeader(raw_ostream &OS);
152 static bool orderByAddress(const Row &LHS, const Row &RHS) {
153 return std::tie(LHS.Address.SectionIndex, LHS.Address.Address) <
154 std::tie(RHS.Address.SectionIndex, RHS.Address.Address);
157 /// The program-counter value corresponding to a machine instruction
158 /// generated by the compiler and section index pointing to the section
159 /// containg this PC. If relocation information is present then section
160 /// index is the index of the section which contains above address.
161 /// Otherwise this is object::SectionedAddress::Undef value.
162 object::SectionedAddress Address;
163 /// An unsigned integer indicating a source line number. Lines are numbered
164 /// beginning at 1. The compiler may emit the value 0 in cases where an
165 /// instruction cannot be attributed to any source line.
167 /// An unsigned integer indicating a column number within a source line.
168 /// Columns are numbered beginning at 1. The value 0 is reserved to indicate
169 /// that a statement begins at the 'left edge' of the line.
171 /// An unsigned integer indicating the identity of the source file
172 /// corresponding to a machine instruction.
174 /// An unsigned integer representing the DWARF path discriminator value
175 /// for this location.
176 uint32_t Discriminator;
177 /// An unsigned integer whose value encodes the applicable instruction set
178 /// architecture for the current instruction.
180 /// A boolean indicating that the current instruction is the beginning of a
183 /// A boolean indicating that the current instruction is the
184 /// beginning of a basic block.
186 /// A boolean indicating that the current address is that of the
187 /// first byte after the end of a sequence of target machine
190 /// A boolean indicating that the current address is one (of possibly
191 /// many) where execution should be suspended for an entry breakpoint
194 /// A boolean indicating that the current address is one (of possibly
195 /// many) where execution should be suspended for an exit breakpoint
200 /// Represents a series of contiguous machine instructions. Line table for
201 /// each compilation unit may consist of multiple sequences, which are not
202 /// guaranteed to be in the order of ascending instruction address.
206 /// Sequence describes instructions at address range [LowPC, HighPC)
207 /// and is described by line table rows [FirstRowIndex, LastRowIndex).
210 /// If relocation information is present then this is the index of the
211 /// section which contains above addresses. Otherwise this is
212 /// object::SectionedAddress::Undef value.
213 uint64_t SectionIndex;
214 unsigned FirstRowIndex;
215 unsigned LastRowIndex;
220 static bool orderByHighPC(const Sequence &LHS, const Sequence &RHS) {
221 return std::tie(LHS.SectionIndex, LHS.HighPC) <
222 std::tie(RHS.SectionIndex, RHS.HighPC);
225 bool isValid() const {
226 return !Empty && (LowPC < HighPC) && (FirstRowIndex < LastRowIndex);
229 bool containsPC(object::SectionedAddress PC) const {
230 return SectionIndex == PC.SectionIndex &&
231 (LowPC <= PC.Address && PC.Address < HighPC);
238 /// Represents an invalid row
239 const uint32_t UnknownRowIndex = UINT32_MAX;
241 void appendRow(const DWARFDebugLine::Row &R) { Rows.push_back(R); }
243 void appendSequence(const DWARFDebugLine::Sequence &S) {
244 Sequences.push_back(S);
247 /// Returns the index of the row with file/line info for a given address,
248 /// or UnknownRowIndex if there is no such row.
249 uint32_t lookupAddress(object::SectionedAddress Address) const;
251 bool lookupAddressRange(object::SectionedAddress Address, uint64_t Size,
252 std::vector<uint32_t> &Result) const;
254 bool hasFileAtIndex(uint64_t FileIndex) const {
255 return Prologue.hasFileAtIndex(FileIndex);
258 /// Extracts filename by its index in filename table in prologue.
259 /// In Dwarf 4, the files are 1-indexed and the current compilation file
260 /// name is not represented in the list. In DWARF v5, the files are
261 /// 0-indexed and the primary source file has the index 0.
262 /// Returns true on success.
263 bool getFileNameByIndex(uint64_t FileIndex, StringRef CompDir,
264 DILineInfoSpecifier::FileLineInfoKind Kind,
265 std::string &Result) const {
266 return Prologue.getFileNameByIndex(FileIndex, CompDir, Kind, Result);
269 /// Fills the Result argument with the file and line information
270 /// corresponding to Address. Returns true on success.
271 bool getFileLineInfoForAddress(object::SectionedAddress Address,
273 DILineInfoSpecifier::FileLineInfoKind Kind,
274 DILineInfo &Result) const;
276 void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
279 /// Parse prologue and all rows.
281 DWARFDataExtractor &DebugLineData, uint32_t *OffsetPtr,
282 const DWARFContext &Ctx, const DWARFUnit *U,
283 std::function<void(Error)> RecoverableErrorCallback,
284 raw_ostream *OS = nullptr);
286 using RowVector = std::vector<Row>;
287 using RowIter = RowVector::const_iterator;
288 using SequenceVector = std::vector<Sequence>;
289 using SequenceIter = SequenceVector::const_iterator;
291 struct Prologue Prologue;
293 SequenceVector Sequences;
296 uint32_t findRowInSeq(const DWARFDebugLine::Sequence &Seq,
297 object::SectionedAddress Address) const;
299 getSourceByIndex(uint64_t FileIndex,
300 DILineInfoSpecifier::FileLineInfoKind Kind) const;
302 uint32_t lookupAddressImpl(object::SectionedAddress Address) const;
304 bool lookupAddressRangeImpl(object::SectionedAddress Address, uint64_t Size,
305 std::vector<uint32_t> &Result) const;
308 const LineTable *getLineTable(uint32_t Offset) const;
309 Expected<const LineTable *> getOrParseLineTable(
310 DWARFDataExtractor &DebugLineData, uint32_t Offset,
311 const DWARFContext &Ctx, const DWARFUnit *U,
312 std::function<void(Error)> RecoverableErrorCallback);
314 /// Helper to allow for parsing of an entire .debug_line section in sequence.
315 class SectionParser {
317 using cu_range = DWARFUnitVector::iterator_range;
318 using tu_range = DWARFUnitVector::iterator_range;
319 using LineToUnitMap = std::map<uint64_t, DWARFUnit *>;
321 SectionParser(DWARFDataExtractor &Data, const DWARFContext &C, cu_range CUs,
324 /// Get the next line table from the section. Report any issues via the
327 /// \param RecoverableErrorCallback - any issues that don't prevent further
328 /// parsing of the table will be reported through this callback.
329 /// \param UnrecoverableErrorCallback - any issues that prevent further
330 /// parsing of the table will be reported through this callback.
331 /// \param OS - if not null, the parser will print information about the
332 /// table as it parses it.
335 function_ref<void(Error)> RecoverableErrorCallback,
336 function_ref<void(Error)> UnrecoverableErrorCallback,
337 raw_ostream *OS = nullptr);
339 /// Skip the current line table and go to the following line table (if
340 /// present) immediately.
342 /// \param ErrorCallback - report any prologue parsing issues via this
344 void skip(function_ref<void(Error)> ErrorCallback);
346 /// Indicates if the parser has parsed as much as possible.
348 /// \note Certain problems with the line table structure might mean that
349 /// parsing stops before the end of the section is reached.
350 bool done() const { return Done; }
352 /// Get the offset the parser has reached.
353 uint32_t getOffset() const { return Offset; }
356 DWARFUnit *prepareToParse(uint32_t Offset);
357 void moveToNextTable(uint32_t OldOffset, const Prologue &P);
359 LineToUnitMap LineToUnit;
361 DWARFDataExtractor &DebugLineData;
362 const DWARFContext &Context;
368 struct ParsingState {
369 ParsingState(struct LineTable *LT);
371 void resetRowAndSequence();
372 void appendRowToMatrix();
374 /// Line table we're currently parsing.
375 struct LineTable *LineTable;
377 struct Sequence Sequence;
380 using LineTableMapTy = std::map<uint32_t, LineTable>;
381 using LineTableIter = LineTableMapTy::iterator;
382 using LineTableConstIter = LineTableMapTy::const_iterator;
384 LineTableMapTy LineTableMap;
387 } // end namespace llvm
389 #endif // LLVM_DEBUGINFO_DWARFDEBUGLINE_H