LLVM  12.0.0git
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_DWARFDEBUGLINE_H
10 #define LLVM_DEBUGINFO_DWARFDEBUGLINE_H
11 
12 #include "llvm/ADT/Optional.h"
13 #include "llvm/ADT/StringRef.h"
20 #include "llvm/Support/MD5.h"
21 #include "llvm/Support/Path.h"
22 #include <cstdint>
23 #include <map>
24 #include <string>
25 #include <vector>
26 
27 namespace llvm {
28 
29 class DWARFUnit;
30 class raw_ostream;
31 
33 public:
34  struct FileNameEntry {
35  FileNameEntry() = default;
36 
38  uint64_t DirIdx = 0;
39  uint64_t ModTime = 0;
40  uint64_t Length = 0;
43  };
44 
45  /// Tracks which optional content types are present in a DWARF file name
46  /// entry format.
48  ContentTypeTracker() = default;
49 
50  /// Whether filename entries provide a modification timestamp.
51  bool HasModTime = false;
52  /// Whether filename entries provide a file size.
53  bool HasLength = false;
54  /// For v5, whether filename entries provide an MD5 checksum.
55  bool HasMD5 = false;
56  /// For v5, whether filename entries provide source text.
57  bool HasSource = false;
58 
59  /// Update tracked content types with \p ContentType.
60  void trackContentType(dwarf::LineNumberEntryFormat ContentType);
61  };
62 
63  struct Prologue {
64  Prologue();
65 
66  /// The size in bytes of the statement information for this compilation unit
67  /// (not including the total_length field itself).
68  uint64_t TotalLength;
69  /// Version, address size (starting in v5), and DWARF32/64 format; these
70  /// parameters affect interpretation of forms (used in the directory and
71  /// file tables starting with v5).
73  /// The number of bytes following the prologue_length field to the beginning
74  /// of the first byte of the statement program itself.
75  uint64_t PrologueLength;
76  /// In v5, size in bytes of a segment selector.
77  uint8_t SegSelectorSize;
78  /// The size in bytes of the smallest target machine instruction. Statement
79  /// program opcodes that alter the address register first multiply their
80  /// operands by this value.
81  uint8_t MinInstLength;
82  /// The maximum number of individual operations that may be encoded in an
83  /// instruction.
84  uint8_t MaxOpsPerInst;
85  /// The initial value of theis_stmtregister.
86  uint8_t DefaultIsStmt;
87  /// This parameter affects the meaning of the special opcodes. See below.
88  int8_t LineBase;
89  /// This parameter affects the meaning of the special opcodes. See below.
90  uint8_t LineRange;
91  /// The number assigned to the first special opcode.
92  uint8_t OpcodeBase;
93  /// This tracks which optional file format content types are present.
95  std::vector<uint8_t> StandardOpcodeLengths;
96  std::vector<DWARFFormValue> IncludeDirectories;
97  std::vector<FileNameEntry> FileNames;
98 
99  const dwarf::FormParams getFormParams() const { return FormParams; }
100  uint16_t getVersion() const { return FormParams.Version; }
101  uint8_t getAddressSize() const { return FormParams.AddrSize; }
102  bool isDWARF64() const { return FormParams.Format == dwarf::DWARF64; }
103 
104  uint32_t sizeofTotalLength() const { return isDWARF64() ? 12 : 4; }
105 
106  uint32_t sizeofPrologueLength() const { return isDWARF64() ? 8 : 4; }
107 
108  bool totalLengthIsValid() const;
109 
110  /// Length of the prologue in bytes.
111  uint64_t getLength() const;
112 
114  return LineBase + (int8_t)LineRange - 1;
115  }
116 
117  /// Get DWARF-version aware access to the file name entry at the provided
118  /// index.
120  getFileNameEntry(uint64_t Index) const;
121 
122  bool hasFileAtIndex(uint64_t FileIndex) const;
123 
124  bool
125  getFileNameByIndex(uint64_t FileIndex, StringRef CompDir,
127  std::string &Result,
129 
130  void clear();
131  void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
132  Error parse(DWARFDataExtractor Data, uint64_t *OffsetPtr,
133  function_ref<void(Error)> RecoverableErrorHandler,
134  const DWARFContext &Ctx, const DWARFUnit *U = nullptr);
135  };
136 
137  /// Standard .debug_line state machine structure.
138  struct Row {
139  explicit Row(bool DefaultIsStmt = false);
140 
141  /// Called after a row is appended to the matrix.
142  void postAppend();
143  void reset(bool DefaultIsStmt);
144  void dump(raw_ostream &OS) const;
145 
146  static void dumpTableHeader(raw_ostream &OS, unsigned Indent);
147 
148  static bool orderByAddress(const Row &LHS, const Row &RHS) {
149  return std::tie(LHS.Address.SectionIndex, LHS.Address.Address) <
150  std::tie(RHS.Address.SectionIndex, RHS.Address.Address);
151  }
152 
153  /// The program-counter value corresponding to a machine instruction
154  /// generated by the compiler and section index pointing to the section
155  /// containg this PC. If relocation information is present then section
156  /// index is the index of the section which contains above address.
157  /// Otherwise this is object::SectionedAddress::Undef value.
159  /// An unsigned integer indicating a source line number. Lines are numbered
160  /// beginning at 1. The compiler may emit the value 0 in cases where an
161  /// instruction cannot be attributed to any source line.
163  /// An unsigned integer indicating a column number within a source line.
164  /// Columns are numbered beginning at 1. The value 0 is reserved to indicate
165  /// that a statement begins at the 'left edge' of the line.
167  /// An unsigned integer indicating the identity of the source file
168  /// corresponding to a machine instruction.
170  /// An unsigned integer representing the DWARF path discriminator value
171  /// for this location.
173  /// An unsigned integer whose value encodes the applicable instruction set
174  /// architecture for the current instruction.
175  uint8_t Isa;
176  /// A boolean indicating that the current instruction is the beginning of a
177  /// statement.
178  uint8_t IsStmt : 1,
179  /// A boolean indicating that the current instruction is the
180  /// beginning of a basic block.
181  BasicBlock : 1,
182  /// A boolean indicating that the current address is that of the
183  /// first byte after the end of a sequence of target machine
184  /// instructions.
185  EndSequence : 1,
186  /// A boolean indicating that the current address is one (of possibly
187  /// many) where execution should be suspended for an entry breakpoint
188  /// of a function.
189  PrologueEnd : 1,
190  /// A boolean indicating that the current address is one (of possibly
191  /// many) where execution should be suspended for an exit breakpoint
192  /// of a function.
193  EpilogueBegin : 1;
194  };
195 
196  /// Represents a series of contiguous machine instructions. Line table for
197  /// each compilation unit may consist of multiple sequences, which are not
198  /// guaranteed to be in the order of ascending instruction address.
199  struct Sequence {
200  Sequence();
201 
202  /// Sequence describes instructions at address range [LowPC, HighPC)
203  /// and is described by line table rows [FirstRowIndex, LastRowIndex).
204  uint64_t LowPC;
205  uint64_t HighPC;
206  /// If relocation information is present then this is the index of the
207  /// section which contains above addresses. Otherwise this is
208  /// object::SectionedAddress::Undef value.
209  uint64_t SectionIndex;
210  unsigned FirstRowIndex;
211  unsigned LastRowIndex;
212  bool Empty;
213 
214  void reset();
215 
216  static bool orderByHighPC(const Sequence &LHS, const Sequence &RHS) {
217  return std::tie(LHS.SectionIndex, LHS.HighPC) <
218  std::tie(RHS.SectionIndex, RHS.HighPC);
219  }
220 
221  bool isValid() const {
222  return !Empty && (LowPC < HighPC) && (FirstRowIndex < LastRowIndex);
223  }
224 
226  return SectionIndex == PC.SectionIndex &&
227  (LowPC <= PC.Address && PC.Address < HighPC);
228  }
229  };
230 
231  struct LineTable {
232  LineTable();
233 
234  /// Represents an invalid row
235  const uint32_t UnknownRowIndex = UINT32_MAX;
236 
237  void appendRow(const DWARFDebugLine::Row &R) { Rows.push_back(R); }
238 
240  Sequences.push_back(S);
241  }
242 
243  /// Returns the index of the row with file/line info for a given address,
244  /// or UnknownRowIndex if there is no such row.
245  uint32_t lookupAddress(object::SectionedAddress Address) const;
246 
247  bool lookupAddressRange(object::SectionedAddress Address, uint64_t Size,
248  std::vector<uint32_t> &Result) const;
249 
250  bool hasFileAtIndex(uint64_t FileIndex) const {
251  return Prologue.hasFileAtIndex(FileIndex);
252  }
253 
254  /// Extracts filename by its index in filename table in prologue.
255  /// In Dwarf 4, the files are 1-indexed and the current compilation file
256  /// name is not represented in the list. In DWARF v5, the files are
257  /// 0-indexed and the primary source file has the index 0.
258  /// Returns true on success.
259  bool getFileNameByIndex(uint64_t FileIndex, StringRef CompDir,
261  std::string &Result) const {
262  return Prologue.getFileNameByIndex(FileIndex, CompDir, Kind, Result);
263  }
264 
265  /// Fills the Result argument with the file and line information
266  /// corresponding to Address. Returns true on success.
267  bool getFileLineInfoForAddress(object::SectionedAddress Address,
268  const char *CompDir,
270  DILineInfo &Result) const;
271 
272  void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
273  void clear();
274 
275  /// Parse prologue and all rows.
276  Error parse(DWARFDataExtractor &DebugLineData, uint64_t *OffsetPtr,
277  const DWARFContext &Ctx, const DWARFUnit *U,
278  function_ref<void(Error)> RecoverableErrorHandler,
279  raw_ostream *OS = nullptr, bool Verbose = false);
280 
281  using RowVector = std::vector<Row>;
282  using RowIter = RowVector::const_iterator;
283  using SequenceVector = std::vector<Sequence>;
284  using SequenceIter = SequenceVector::const_iterator;
285 
289 
290  private:
291  uint32_t findRowInSeq(const DWARFDebugLine::Sequence &Seq,
292  object::SectionedAddress Address) const;
294  getSourceByIndex(uint64_t FileIndex,
296 
297  uint32_t lookupAddressImpl(object::SectionedAddress Address) const;
298 
299  bool lookupAddressRangeImpl(object::SectionedAddress Address, uint64_t Size,
300  std::vector<uint32_t> &Result) const;
301  };
302 
303  const LineTable *getLineTable(uint64_t Offset) const;
305  getOrParseLineTable(DWARFDataExtractor &DebugLineData, uint64_t Offset,
306  const DWARFContext &Ctx, const DWARFUnit *U,
307  function_ref<void(Error)> RecoverableErrorHandler);
308 
309  /// Helper to allow for parsing of an entire .debug_line section in sequence.
311  public:
314  using LineToUnitMap = std::map<uint64_t, DWARFUnit *>;
315 
317  tu_range TUs);
318 
319  /// Get the next line table from the section. Report any issues via the
320  /// handlers.
321  ///
322  /// \param RecoverableErrorHandler - any issues that don't prevent further
323  /// parsing of the table will be reported through this handler.
324  /// \param UnrecoverableErrorHandler - any issues that prevent further
325  /// parsing of the table will be reported through this handler.
326  /// \param OS - if not null, the parser will print information about the
327  /// table as it parses it.
328  /// \param Verbose - if true, the parser will print verbose information when
329  /// printing to the output.
330  LineTable parseNext(function_ref<void(Error)> RecoverableErrorHandler,
331  function_ref<void(Error)> UnrecoverableErrorHandler,
332  raw_ostream *OS = nullptr, bool Verbose = false);
333 
334  /// Skip the current line table and go to the following line table (if
335  /// present) immediately.
336  ///
337  /// \param RecoverableErrorHandler - report any recoverable prologue
338  /// parsing issues via this handler.
339  /// \param UnrecoverableErrorHandler - report any unrecoverable prologue
340  /// parsing issues via this handler.
341  void skip(function_ref<void(Error)> RecoverableErrorHandler,
342  function_ref<void(Error)> UnrecoverableErrorHandler);
343 
344  /// Indicates if the parser has parsed as much as possible.
345  ///
346  /// \note Certain problems with the line table structure might mean that
347  /// parsing stops before the end of the section is reached.
348  bool done() const { return Done; }
349 
350  /// Get the offset the parser has reached.
351  uint64_t getOffset() const { return Offset; }
352 
353  private:
354  DWARFUnit *prepareToParse(uint64_t Offset);
355  void moveToNextTable(uint64_t OldOffset, const Prologue &P);
356 
357  LineToUnitMap LineToUnit;
358 
359  DWARFDataExtractor &DebugLineData;
360  const DWARFContext &Context;
361  uint64_t Offset = 0;
362  bool Done = false;
363  };
364 
365 private:
366  struct ParsingState {
367  ParsingState(struct LineTable *LT, uint64_t TableOffset,
369 
370  void resetRowAndSequence();
371  void appendRowToMatrix();
372 
373  /// Advance the address by the \p OperationAdvance value. \returns the
374  /// amount advanced by.
375  uint64_t advanceAddr(uint64_t OperationAdvance, uint8_t Opcode,
376  uint64_t OpcodeOffset);
377 
379  uint64_t AddrDelta;
380  uint8_t AdjustedOpcode;
381  };
382 
383  /// Advance the address as required by the specified \p Opcode.
384  /// \returns the amount advanced by and the calculated adjusted opcode.
385  AddrAndAdjustedOpcode advanceAddrForOpcode(uint8_t Opcode,
386  uint64_t OpcodeOffset);
387 
389  uint64_t Address;
390  int32_t Line;
391  };
392 
393  /// Advance the line and address as required by the specified special \p
394  /// Opcode. \returns the address and line delta.
395  AddrAndLineDelta handleSpecialOpcode(uint8_t Opcode, uint64_t OpcodeOffset);
396 
397  /// Line table we're currently parsing.
398  struct LineTable *LineTable;
399  struct Row Row;
400  struct Sequence Sequence;
401 
402  private:
403  uint64_t LineTableOffset;
404 
405  bool ReportAdvanceAddrProblem = true;
406  bool ReportBadLineRange = true;
408  };
409 
410  using LineTableMapTy = std::map<uint64_t, LineTable>;
411  using LineTableIter = LineTableMapTy::iterator;
412  using LineTableConstIter = LineTableMapTy::const_iterator;
413 
414  LineTableMapTy LineTableMap;
415 };
416 
417 } // end namespace llvm
418 
419 #endif // LLVM_DEBUGINFO_DWARFDEBUGLINE_H
SequenceVector::const_iterator SequenceIter
uint64_t CallInst * C
A helper struct providing information about the byte size of DW_FORM values that vary in size dependi...
Definition: Dwarf.h:554
uint64_t LowPC
Sequence describes instructions at address range [LowPC, HighPC) and is described by line table rows ...
LLVMContext & Context
This class represents lattice values for constants.
Definition: AllocatorList.h:23
Various leaf nodes.
Definition: ISDOpcodes.h:64
std::vector< Sequence > SequenceVector
uint32_t sizeofTotalLength() const
static bool orderByAddress(const Row &LHS, const Row &RHS)
static bool skip(DataExtractor &Data, uint64_t &Offset, bool SkippedRanges)
Skip an InlineInfo object in the specified data at the specified offset.
Definition: InlineInfo.cpp:76
uint8_t MinInstLength
The size in bytes of the smallest target machine instruction.
An efficient, type-erasing, non-owning reference to a callable.
Definition: STLExtras.h:176
uint32_t Line
An unsigned integer indicating a source line number.
bool getFileNameByIndex(uint64_t FileIndex, StringRef CompDir, DILineInfoSpecifier::FileLineInfoKind Kind, std::string &Result) const
Extracts filename by its index in filename table in prologue.
const dwarf::FormParams getFormParams() const
std::vector< DWARFFormValue > IncludeDirectories
uint64_t getOffset() const
Get the offset the parser has reached.
A format-neutral container for source line information.
Definition: DIContext.h:31
bool hasFileAtIndex(uint64_t FileIndex) const
object::SectionedAddress Address
The program-counter value corresponding to a machine instruction generated by the compiler and sectio...
uint8_t Isa
An unsigned integer whose value encodes the applicable instruction set architecture for the current i...
uint8_t MaxOpsPerInst
The maximum number of individual operations that may be encoded in an instruction.
uint64_t SectionIndex
If relocation information is present then this is the index of the section which contains above addre...
dwarf::FormParams FormParams
Version, address size (starting in v5), and DWARF32/64 format; these parameters affect interpretation...
ContentTypeTracker ContentTypes
This tracks which optional file format content types are present.
Represents a series of contiguous machine instructions.
uint32_t sizeofPrologueLength() const
Tagged union holding either a T or a Error.
Definition: APFloat.h:42
uint8_t LineRange
This parameter affects the meaning of the special opcodes. See below.
static fatal_error_handler_t ErrorHandler
uint8_t OpcodeBase
The number assigned to the first special opcode.
llvm::iterator_range< typename UnitVector::iterator > iterator_range
Definition: DWARFUnit.h:128
uint64_t TotalLength
The size in bytes of the statement information for this compilation unit (not including the total_len...
Container for dump options that control which debug information will be dumped.
Definition: DIContext.h:181
bool getFileNameByIndex(uint64_t FileIndex, StringRef CompDir, DILineInfoSpecifier::FileLineInfoKind Kind, std::string &Result, sys::path::Style Style=sys::path::Style::native) const
#define P(N)
void dump(const SparseBitVector< ElementSize > &LHS, raw_ostream &out)
uint8_t SegSelectorSize
In v5, size in bytes of a segment selector.
Expected< const LineTable * > getOrParseLineTable(DWARFDataExtractor &DebugLineData, uint64_t Offset, const DWARFContext &Ctx, const DWARFUnit *U, function_ref< void(Error)> RecoverableErrorHandler)
uint16_t File
An unsigned integer indicating the identity of the source file corresponding to a machine instruction...
uint64_t PrologueLength
The number of bytes following the prologue_length field to the beginning of the first byte of the sta...
bool hasFileAtIndex(uint64_t FileIndex) const
static bool orderByHighPC(const Sequence &LHS, const Sequence &RHS)
int32_t getMaxLineIncrementForSpecialOpcode() const
void appendSequence(const DWARFDebugLine::Sequence &S)
Standard .debug_line state machine structure.
A DataExtractor (typically for an in-memory copy of an object-file section) plus a relocation map for...
uint16_t Column
An unsigned integer indicating a column number within a source line.
std::map< uint64_t, DWARFUnit * > LineToUnitMap
End of the line table.
Definition: LineTable.cpp:17
void appendRow(const DWARFDebugLine::Row &R)
DWARFContext This data structure is the top level entity that deals with dwarf debug information pars...
Definition: DWARFContext.h:53
uint8_t PrologueEnd
A boolean indicating that the current address is one (of possibly many) where execution should be sus...
std::vector< uint8_t > StandardOpcodeLengths
A range adaptor for a pair of iterators.
const LineTable * getLineTable(uint64_t Offset) const
static void clear(coro::Shape &Shape)
Definition: Coroutines.cpp:225
Tracks which optional content types are present in a DWARF file name entry format.
std::vector< FileNameEntry > FileNames
uint32_t Discriminator
An unsigned integer representing the DWARF path discriminator value for this location.
RowVector::const_iterator RowIter
Sequence
A sequence of states that a pointer may go through in which an objc_retain and objc_release are actua...
Definition: PtrState.h:40
uint32_t Size
Definition: Profile.cpp:46
uint8_t DefaultIsStmt
The initial value of theis_stmtregister.
DwarfFormat Format
Definition: Dwarf.h:557
bool containsPC(object::SectionedAddress PC) const
int8_t LineBase
This parameter affects the meaning of the special opcodes. See below.
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:46
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:57
static llvm::Error parse(DataExtractor &Data, uint64_t BaseAddr, LineEntryCallback const &Callback)
Definition: LineTable.cpp:54
LineNumberEntryFormat
Definition: Dwarf.h:288
Helper to allow for parsing of an entire .debug_line section in sequence.
bool done() const
Indicates if the parser has parsed as much as possible.