LLVM 19.0.0git
DWARFDebugLine.h
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1//===- DWARFDebugLine.h -----------------------------------------*- C++ -*-===//
2//
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
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef LLVM_DEBUGINFO_DWARF_DWARFDEBUGLINE_H
10#define LLVM_DEBUGINFO_DWARF_DWARFDEBUGLINE_H
11
12#include "llvm/ADT/StringRef.h"
17#include "llvm/Support/MD5.h"
18#include "llvm/Support/Path.h"
19#include <cstdint>
20#include <map>
21#include <string>
22#include <vector>
23
24namespace llvm {
25
26class raw_ostream;
27
29public:
31 FileNameEntry() = default;
32
39 };
40
41 /// Tracks which optional content types are present in a DWARF file name
42 /// entry format.
44 ContentTypeTracker() = default;
45
46 /// Whether filename entries provide a modification timestamp.
47 bool HasModTime = false;
48 /// Whether filename entries provide a file size.
49 bool HasLength = false;
50 /// For v5, whether filename entries provide an MD5 checksum.
51 bool HasMD5 = false;
52 /// For v5, whether filename entries provide source text.
53 bool HasSource = false;
54
55 /// Update tracked content types with \p ContentType.
57 };
58
59 struct Prologue {
60 Prologue();
61
62 /// The size in bytes of the statement information for this compilation unit
63 /// (not including the total_length field itself).
65 /// Version, address size (starting in v5), and DWARF32/64 format; these
66 /// parameters affect interpretation of forms (used in the directory and
67 /// file tables starting with v5).
69 /// The number of bytes following the prologue_length field to the beginning
70 /// of the first byte of the statement program itself.
72 /// In v5, size in bytes of a segment selector.
74 /// The size in bytes of the smallest target machine instruction. Statement
75 /// program opcodes that alter the address register first multiply their
76 /// operands by this value.
78 /// The maximum number of individual operations that may be encoded in an
79 /// instruction.
81 /// The initial value of theis_stmtregister.
83 /// This parameter affects the meaning of the special opcodes. See below.
84 int8_t LineBase;
85 /// This parameter affects the meaning of the special opcodes. See below.
86 uint8_t LineRange;
87 /// The number assigned to the first special opcode.
88 uint8_t OpcodeBase;
89 /// This tracks which optional file format content types are present.
91 std::vector<uint8_t> StandardOpcodeLengths;
92 std::vector<DWARFFormValue> IncludeDirectories;
93 std::vector<FileNameEntry> FileNames;
94
95 const dwarf::FormParams getFormParams() const { return FormParams; }
97 uint8_t getAddressSize() const { return FormParams.AddrSize; }
98 bool isDWARF64() const { return FormParams.Format == dwarf::DWARF64; }
99
100 uint32_t sizeofTotalLength() const { return isDWARF64() ? 12 : 4; }
101
102 uint32_t sizeofPrologueLength() const { return isDWARF64() ? 8 : 4; }
103
104 bool totalLengthIsValid() const;
105
106 /// Length of the prologue in bytes.
107 uint64_t getLength() const;
108
109 /// Get DWARF-version aware access to the file name entry at the provided
110 /// index.
113
114 bool hasFileAtIndex(uint64_t FileIndex) const;
115
116 std::optional<uint64_t> getLastValidFileIndex() const;
117
118 bool
119 getFileNameByIndex(uint64_t FileIndex, StringRef CompDir,
121 std::string &Result,
123
124 void clear();
125 void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
127 function_ref<void(Error)> RecoverableErrorHandler,
128 const DWARFContext &Ctx, const DWARFUnit *U = nullptr);
129 };
130
131 /// Standard .debug_line state machine structure.
132 struct Row {
133 explicit Row(bool DefaultIsStmt = false);
134
135 /// Called after a row is appended to the matrix.
136 void postAppend();
137 void reset(bool DefaultIsStmt);
138 void dump(raw_ostream &OS) const;
139
140 static void dumpTableHeader(raw_ostream &OS, unsigned Indent);
141
142 static bool orderByAddress(const Row &LHS, const Row &RHS) {
143 return std::tie(LHS.Address.SectionIndex, LHS.Address.Address) <
144 std::tie(RHS.Address.SectionIndex, RHS.Address.Address);
145 }
146
147 /// The program-counter value corresponding to a machine instruction
148 /// generated by the compiler and section index pointing to the section
149 /// containg this PC. If relocation information is present then section
150 /// index is the index of the section which contains above address.
151 /// Otherwise this is object::SectionedAddress::Undef value.
153 /// An unsigned integer indicating a source line number. Lines are numbered
154 /// beginning at 1. The compiler may emit the value 0 in cases where an
155 /// instruction cannot be attributed to any source line.
157 /// An unsigned integer indicating a column number within a source line.
158 /// Columns are numbered beginning at 1. The value 0 is reserved to indicate
159 /// that a statement begins at the 'left edge' of the line.
161 /// An unsigned integer indicating the identity of the source file
162 /// corresponding to a machine instruction.
164 /// An unsigned integer representing the DWARF path discriminator value
165 /// for this location.
167 /// An unsigned integer whose value encodes the applicable instruction set
168 /// architecture for the current instruction.
169 uint8_t Isa;
170 /// An unsigned integer representing the index of an operation within a
171 /// VLIW instruction. The index of the first operation is 0.
172 /// For non-VLIW architectures, this register will always be 0.
173 uint8_t OpIndex;
174 /// A boolean indicating that the current instruction is the beginning of a
175 /// statement.
176 uint8_t IsStmt : 1,
177 /// A boolean indicating that the current instruction is the
178 /// beginning of a basic block.
180 /// A boolean indicating that the current address is that of the
181 /// first byte after the end of a sequence of target machine
182 /// instructions.
184 /// A boolean indicating that the current address is one (of possibly
185 /// many) where execution should be suspended for an entry breakpoint
186 /// of a function.
188 /// A boolean indicating that the current address is one (of possibly
189 /// many) where execution should be suspended for an exit breakpoint
190 /// of a function.
192 };
193
194 /// Represents a series of contiguous machine instructions. Line table for
195 /// each compilation unit may consist of multiple sequences, which are not
196 /// guaranteed to be in the order of ascending instruction address.
197 struct Sequence {
198 Sequence();
199
200 /// Sequence describes instructions at address range [LowPC, HighPC)
201 /// and is described by line table rows [FirstRowIndex, LastRowIndex).
204 /// If relocation information is present then this is the index of the
205 /// section which contains above addresses. Otherwise this is
206 /// object::SectionedAddress::Undef value.
209 unsigned LastRowIndex;
210 bool Empty;
211
212 void reset();
213
214 static bool orderByHighPC(const Sequence &LHS, const Sequence &RHS) {
215 return std::tie(LHS.SectionIndex, LHS.HighPC) <
216 std::tie(RHS.SectionIndex, RHS.HighPC);
217 }
218
219 bool isValid() const {
220 return !Empty && (LowPC < HighPC) && (FirstRowIndex < LastRowIndex);
221 }
222
224 return SectionIndex == PC.SectionIndex &&
225 (LowPC <= PC.Address && PC.Address < HighPC);
226 }
227 };
228
229 struct LineTable {
230 LineTable();
231
232 /// Represents an invalid row
233 const uint32_t UnknownRowIndex = UINT32_MAX;
234
235 void appendRow(const DWARFDebugLine::Row &R) { Rows.push_back(R); }
236
238 Sequences.push_back(S);
239 }
240
241 /// Returns the index of the row with file/line info for a given address,
242 /// or UnknownRowIndex if there is no such row.
244
246 std::vector<uint32_t> &Result) const;
247
248 bool hasFileAtIndex(uint64_t FileIndex) const {
249 return Prologue.hasFileAtIndex(FileIndex);
250 }
251
252 std::optional<uint64_t> getLastValidFileIndex() const {
254 }
255
256 /// Extracts filename by its index in filename table in prologue.
257 /// In Dwarf 4, the files are 1-indexed and the current compilation file
258 /// name is not represented in the list. In DWARF v5, the files are
259 /// 0-indexed and the primary source file has the index 0.
260 /// Returns true on success.
261 bool getFileNameByIndex(uint64_t FileIndex, StringRef CompDir,
263 std::string &Result) const {
264 return Prologue.getFileNameByIndex(FileIndex, CompDir, Kind, Result);
265 }
266
267 /// Fills the Result argument with the file and line information
268 /// corresponding to Address. Returns true on success.
270 const char *CompDir,
272 DILineInfo &Result) const;
273
274 /// Extracts directory name by its Entry in include directories table
275 /// in prologue. Returns true on success.
276 bool getDirectoryForEntry(const FileNameEntry &Entry,
277 std::string &Directory) const;
278
279 void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
280 void clear();
281
282 /// Parse prologue and all rows.
283 Error parse(DWARFDataExtractor &DebugLineData, uint64_t *OffsetPtr,
284 const DWARFContext &Ctx, const DWARFUnit *U,
285 function_ref<void(Error)> RecoverableErrorHandler,
286 raw_ostream *OS = nullptr, bool Verbose = false);
287
288 using RowVector = std::vector<Row>;
289 using RowIter = RowVector::const_iterator;
290 using SequenceVector = std::vector<Sequence>;
291 using SequenceIter = SequenceVector::const_iterator;
292
296
297 private:
298 uint32_t findRowInSeq(const DWARFDebugLine::Sequence &Seq,
300 std::optional<StringRef>
301 getSourceByIndex(uint64_t FileIndex,
303
304 uint32_t lookupAddressImpl(object::SectionedAddress Address) const;
305
306 bool lookupAddressRangeImpl(object::SectionedAddress Address, uint64_t Size,
307 std::vector<uint32_t> &Result) const;
308 };
309
313 const DWARFContext &Ctx, const DWARFUnit *U,
314 function_ref<void(Error)> RecoverableErrorHandler);
316
317 /// Helper to allow for parsing of an entire .debug_line section in sequence.
319 public:
320 using LineToUnitMap = std::map<uint64_t, DWARFUnit *>;
321
324
325 /// Get the next line table from the section. Report any issues via the
326 /// handlers.
327 ///
328 /// \param RecoverableErrorHandler - any issues that don't prevent further
329 /// parsing of the table will be reported through this handler.
330 /// \param UnrecoverableErrorHandler - any issues that prevent further
331 /// parsing of the table will be reported through this handler.
332 /// \param OS - if not null, the parser will print information about the
333 /// table as it parses it.
334 /// \param Verbose - if true, the parser will print verbose information when
335 /// printing to the output.
336 LineTable parseNext(function_ref<void(Error)> RecoverableErrorHandler,
337 function_ref<void(Error)> UnrecoverableErrorHandler,
338 raw_ostream *OS = nullptr, bool Verbose = false);
339
340 /// Skip the current line table and go to the following line table (if
341 /// present) immediately.
342 ///
343 /// \param RecoverableErrorHandler - report any recoverable prologue
344 /// parsing issues via this handler.
345 /// \param UnrecoverableErrorHandler - report any unrecoverable prologue
346 /// parsing issues via this handler.
347 void skip(function_ref<void(Error)> RecoverableErrorHandler,
348 function_ref<void(Error)> UnrecoverableErrorHandler);
349
350 /// Indicates if the parser has parsed as much as possible.
351 ///
352 /// \note Certain problems with the line table structure might mean that
353 /// parsing stops before the end of the section is reached.
354 bool done() const { return Done; }
355
356 /// Get the offset the parser has reached.
357 uint64_t getOffset() const { return Offset; }
358
359 private:
360 DWARFUnit *prepareToParse(uint64_t Offset);
361 void moveToNextTable(uint64_t OldOffset, const Prologue &P);
362 bool hasValidVersion(uint64_t Offset);
363
364 LineToUnitMap LineToUnit;
365
366 DWARFDataExtractor &DebugLineData;
367 const DWARFContext &Context;
368 uint64_t Offset = 0;
369 bool Done = false;
370 };
371
372private:
373 struct ParsingState {
374 ParsingState(struct LineTable *LT, uint64_t TableOffset,
375 function_ref<void(Error)> ErrorHandler);
376
377 void resetRowAndSequence();
378 void appendRowToMatrix();
379
383 };
384
385 /// Advance the address and op-index by the \p OperationAdvance value.
386 /// \returns the amount advanced by.
387 AddrOpIndexDelta advanceAddrOpIndex(uint64_t OperationAdvance,
388 uint8_t Opcode, uint64_t OpcodeOffset);
389
394 };
395
396 /// Advance the address and op-index as required by the specified \p Opcode.
397 /// \returns the amount advanced by and the calculated adjusted opcode.
398 OpcodeAdvanceResults advanceForOpcode(uint8_t Opcode,
399 uint64_t OpcodeOffset);
400
403 int32_t Line;
404 int16_t OpIndex;
405 };
406
407 /// Advance the line, address and op-index as required by the specified
408 /// special \p Opcode. \returns the address, op-index and line delta.
409 SpecialOpcodeDelta handleSpecialOpcode(uint8_t Opcode,
410 uint64_t OpcodeOffset);
411
412 /// Line table we're currently parsing.
413 struct LineTable *LineTable;
414 struct Row Row;
415 struct Sequence Sequence;
416
417 private:
418 uint64_t LineTableOffset;
419
420 bool ReportAdvanceAddrProblem = true;
421 bool ReportBadLineRange = true;
423 };
424
425 using LineTableMapTy = std::map<uint64_t, LineTable>;
426 using LineTableIter = LineTableMapTy::iterator;
427 using LineTableConstIter = LineTableMapTy::const_iterator;
428
429 LineTableMapTy LineTableMap;
430};
431
432} // end namespace llvm
433
434#endif // LLVM_DEBUGINFO_DWARF_DWARFDEBUGLINE_H
This file contains constants used for implementing Dwarf debug support.
uint64_t Size
static fatal_error_handler_t ErrorHandler
#define P(N)
raw_pwrite_stream & OS
Value * RHS
Value * LHS
DWARFContext This data structure is the top level entity that deals with dwarf debug information pars...
Definition: DWARFContext.h:48
A DataExtractor (typically for an in-memory copy of an object-file section) plus a relocation map for...
Helper to allow for parsing of an entire .debug_line section in sequence.
void skip(function_ref< void(Error)> RecoverableErrorHandler, function_ref< void(Error)> UnrecoverableErrorHandler)
Skip the current line table and go to the following line table (if present) immediately.
uint64_t getOffset() const
Get the offset the parser has reached.
std::map< uint64_t, DWARFUnit * > LineToUnitMap
LineTable parseNext(function_ref< void(Error)> RecoverableErrorHandler, function_ref< void(Error)> UnrecoverableErrorHandler, raw_ostream *OS=nullptr, bool Verbose=false)
Get the next line table from the section.
bool done() const
Indicates if the parser has parsed as much as possible.
void clearLineTable(uint64_t Offset)
Expected< const LineTable * > getOrParseLineTable(DWARFDataExtractor &DebugLineData, uint64_t Offset, const DWARFContext &Ctx, const DWARFUnit *U, function_ref< void(Error)> RecoverableErrorHandler)
const LineTable * getLineTable(uint64_t Offset) const
Lightweight error class with error context and mandatory checking.
Definition: Error.h:160
Tagged union holding either a T or a Error.
Definition: Error.h:481
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
An efficient, type-erasing, non-owning reference to a callable.
A range adaptor for a pair of iterators.
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
@ C
The default llvm calling convention, compatible with C.
Definition: CallingConv.h:34
LineNumberEntryFormat
Definition: Dwarf.h:780
@ DWARF64
Definition: Dwarf.h:91
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:456
Container for dump options that control which debug information will be dumped.
Definition: DIContext.h:193
A format-neutral container for source line information.
Definition: DIContext.h:32
Tracks which optional content types are present in a DWARF file name entry format.
bool HasLength
Whether filename entries provide a file size.
bool HasSource
For v5, whether filename entries provide source text.
bool HasModTime
Whether filename entries provide a modification timestamp.
bool HasMD5
For v5, whether filename entries provide an MD5 checksum.
void trackContentType(dwarf::LineNumberEntryFormat ContentType)
Update tracked content types with ContentType.
bool getDirectoryForEntry(const FileNameEntry &Entry, std::string &Directory) const
Extracts directory name by its Entry in include directories table in prologue.
const uint32_t UnknownRowIndex
Represents an invalid row.
std::optional< uint64_t > getLastValidFileIndex() const
bool hasFileAtIndex(uint64_t FileIndex) const
uint32_t lookupAddress(object::SectionedAddress Address) const
Returns the index of the row with file/line info for a given address, or UnknownRowIndex if there is ...
bool getFileLineInfoForAddress(object::SectionedAddress Address, const char *CompDir, DILineInfoSpecifier::FileLineInfoKind Kind, DILineInfo &Result) const
Fills the Result argument with the file and line information corresponding to Address.
bool getFileNameByIndex(uint64_t FileIndex, StringRef CompDir, DILineInfoSpecifier::FileLineInfoKind Kind, std::string &Result) const
Extracts filename by its index in filename table in prologue.
RowVector::const_iterator RowIter
bool lookupAddressRange(object::SectionedAddress Address, uint64_t Size, std::vector< uint32_t > &Result) const
SequenceVector::const_iterator SequenceIter
std::vector< Sequence > SequenceVector
void appendSequence(const DWARFDebugLine::Sequence &S)
void appendRow(const DWARFDebugLine::Row &R)
void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const
uint8_t MaxOpsPerInst
The maximum number of individual operations that may be encoded in an instruction.
uint8_t MinInstLength
The size in bytes of the smallest target machine instruction.
bool hasFileAtIndex(uint64_t FileIndex) const
uint64_t PrologueLength
The number of bytes following the prologue_length field to the beginning of the first byte of the sta...
void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const
uint32_t sizeofTotalLength() const
uint8_t SegSelectorSize
In v5, size in bytes of a segment selector.
int8_t LineBase
This parameter affects the meaning of the special opcodes. See below.
std::optional< uint64_t > getLastValidFileIndex() const
uint32_t sizeofPrologueLength() const
uint8_t LineRange
This parameter affects the meaning of the special opcodes. See below.
const dwarf::FormParams getFormParams() const
std::vector< DWARFFormValue > IncludeDirectories
uint8_t OpcodeBase
The number assigned to the first special opcode.
std::vector< uint8_t > StandardOpcodeLengths
const llvm::DWARFDebugLine::FileNameEntry & getFileNameEntry(uint64_t Index) const
Get DWARF-version aware access to the file name entry at the provided index.
bool getFileNameByIndex(uint64_t FileIndex, StringRef CompDir, DILineInfoSpecifier::FileLineInfoKind Kind, std::string &Result, sys::path::Style Style=sys::path::Style::native) const
uint8_t DefaultIsStmt
The initial value of theis_stmtregister.
uint64_t TotalLength
The size in bytes of the statement information for this compilation unit (not including the total_len...
dwarf::FormParams FormParams
Version, address size (starting in v5), and DWARF32/64 format; these parameters affect interpretation...
uint64_t getLength() const
Length of the prologue in bytes.
ContentTypeTracker ContentTypes
This tracks which optional file format content types are present.
std::vector< FileNameEntry > FileNames
Standard .debug_line state machine structure.
uint8_t BasicBlock
A boolean indicating that the current instruction is the beginning of a basic block.
static bool orderByAddress(const Row &LHS, const Row &RHS)
uint32_t Line
An unsigned integer indicating a source line number.
uint16_t File
An unsigned integer indicating the identity of the source file corresponding to a machine instruction...
uint32_t Discriminator
An unsigned integer representing the DWARF path discriminator value for this location.
uint8_t EpilogueBegin
A boolean indicating that the current address is one (of possibly many) where execution should be sus...
object::SectionedAddress Address
The program-counter value corresponding to a machine instruction generated by the compiler and sectio...
void postAppend()
Called after a row is appended to the matrix.
uint8_t PrologueEnd
A boolean indicating that the current address is one (of possibly many) where execution should be sus...
uint16_t Column
An unsigned integer indicating a column number within a source line.
uint8_t EndSequence
A boolean indicating that the current address is that of the first byte after the end of a sequence o...
static void dumpTableHeader(raw_ostream &OS, unsigned Indent)
uint8_t IsStmt
A boolean indicating that the current instruction is the beginning of a statement.
void reset(bool DefaultIsStmt)
uint8_t Isa
An unsigned integer whose value encodes the applicable instruction set architecture for the current i...
void dump(raw_ostream &OS) const
uint8_t OpIndex
An unsigned integer representing the index of an operation within a VLIW instruction.
Represents a series of contiguous machine instructions.
uint64_t LowPC
Sequence describes instructions at address range [LowPC, HighPC) and is described by line table rows ...
static bool orderByHighPC(const Sequence &LHS, const Sequence &RHS)
bool containsPC(object::SectionedAddress PC) const
uint64_t SectionIndex
If relocation information is present then this is the index of the section which contains above addre...
A helper struct providing information about the byte size of DW_FORM values that vary in size dependi...
Definition: Dwarf.h:1077
DwarfFormat Format
Definition: Dwarf.h:1080
Definition: regcomp.c:192