LLVM  8.0.0svn
DWARFDebugLine.h
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1 //===- DWARFDebugLine.h -----------------------------------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef LLVM_DEBUGINFO_DWARFDEBUGLINE_H
11 #define LLVM_DEBUGINFO_DWARFDEBUGLINE_H
12 
13 #include "llvm/ADT/Optional.h"
14 #include "llvm/ADT/StringRef.h"
21 #include "llvm/Support/MD5.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  uint32_t getLength() const {
112  return PrologueLength + sizeofTotalLength() + sizeof(getVersion()) +
113  sizeofPrologueLength();
114  }
115 
116  /// Length of the line table data in bytes (not including the prologue).
118  return TotalLength + sizeofTotalLength() - getLength();
119  }
120 
122  return LineBase + (int8_t)LineRange - 1;
123  }
124 
125  void clear();
126  void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
127  Error parse(const DWARFDataExtractor &DebugLineData, uint32_t *OffsetPtr,
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);
141 
142  static bool orderByAddress(const Row &LHS, const Row &RHS) {
143  return LHS.Address < RHS.Address;
144  }
145 
146  /// The program-counter value corresponding to a machine instruction
147  /// generated by the compiler.
148  uint64_t Address;
149  /// An unsigned integer indicating a source line number. Lines are numbered
150  /// beginning at 1. The compiler may emit the value 0 in cases where an
151  /// instruction cannot be attributed to any source line.
153  /// An unsigned integer indicating a column number within a source line.
154  /// Columns are numbered beginning at 1. The value 0 is reserved to indicate
155  /// that a statement begins at the 'left edge' of the line.
156  uint16_t Column;
157  /// An unsigned integer indicating the identity of the source file
158  /// corresponding to a machine instruction.
159  uint16_t File;
160  /// An unsigned integer representing the DWARF path discriminator value
161  /// for this location.
163  /// An unsigned integer whose value encodes the applicable instruction set
164  /// architecture for the current instruction.
165  uint8_t Isa;
166  /// A boolean indicating that the current instruction is the beginning of a
167  /// statement.
168  uint8_t IsStmt : 1,
169  /// A boolean indicating that the current instruction is the
170  /// beginning of a basic block.
171  BasicBlock : 1,
172  /// A boolean indicating that the current address is that of the
173  /// first byte after the end of a sequence of target machine
174  /// instructions.
175  EndSequence : 1,
176  /// A boolean indicating that the current address is one (of possibly
177  /// many) where execution should be suspended for an entry breakpoint
178  /// of a function.
179  PrologueEnd : 1,
180  /// A boolean indicating that the current address is one (of possibly
181  /// many) where execution should be suspended for an exit breakpoint
182  /// of a function.
183  EpilogueBegin : 1;
184  };
185 
186  /// Represents a series of contiguous machine instructions. Line table for
187  /// each compilation unit may consist of multiple sequences, which are not
188  /// guaranteed to be in the order of ascending instruction address.
189  struct Sequence {
190  Sequence();
191 
192  /// Sequence describes instructions at address range [LowPC, HighPC)
193  /// and is described by line table rows [FirstRowIndex, LastRowIndex).
194  uint64_t LowPC;
195  uint64_t HighPC;
196  unsigned FirstRowIndex;
197  unsigned LastRowIndex;
198  bool Empty;
199 
200  void reset();
201 
202  static bool orderByLowPC(const Sequence &LHS, const Sequence &RHS) {
203  return LHS.LowPC < RHS.LowPC;
204  }
205 
206  bool isValid() const {
207  return !Empty && (LowPC < HighPC) && (FirstRowIndex < LastRowIndex);
208  }
209 
210  bool containsPC(uint64_t PC) const { return (LowPC <= PC && PC < HighPC); }
211  };
212 
213  struct LineTable {
214  LineTable();
215 
216  /// Represents an invalid row
217  const uint32_t UnknownRowIndex = UINT32_MAX;
218 
219  void appendRow(const DWARFDebugLine::Row &R) { Rows.push_back(R); }
220 
222  Sequences.push_back(S);
223  }
224 
225  /// Returns the index of the row with file/line info for a given address,
226  /// or UnknownRowIndex if there is no such row.
227  uint32_t lookupAddress(uint64_t Address) const;
228 
229  bool lookupAddressRange(uint64_t Address, uint64_t Size,
230  std::vector<uint32_t> &Result) const;
231 
232  bool hasFileAtIndex(uint64_t FileIndex) const;
233 
234  /// Extracts filename by its index in filename table in prologue.
235  /// Returns true on success.
236  bool getFileNameByIndex(uint64_t FileIndex, const char *CompDir,
238  std::string &Result) const;
239 
240  /// Fills the Result argument with the file and line information
241  /// corresponding to Address. Returns true on success.
242  bool getFileLineInfoForAddress(uint64_t Address, const char *CompDir,
244  DILineInfo &Result) const;
245 
246  void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
247  void clear();
248 
249  /// Parse prologue and all rows.
250  Error parse(
251  DWARFDataExtractor &DebugLineData, uint32_t *OffsetPtr,
252  const DWARFContext &Ctx, const DWARFUnit *U,
253  std::function<void(Error)> RecoverableErrorCallback,
254  raw_ostream *OS = nullptr);
255 
256  using RowVector = std::vector<Row>;
257  using RowIter = RowVector::const_iterator;
258  using SequenceVector = std::vector<Sequence>;
259  using SequenceIter = SequenceVector::const_iterator;
260 
264 
265  private:
266  uint32_t findRowInSeq(const DWARFDebugLine::Sequence &Seq,
267  uint64_t Address) const;
269  getSourceByIndex(uint64_t FileIndex,
271  };
272 
273  const LineTable *getLineTable(uint32_t Offset) const;
275  DWARFDataExtractor &DebugLineData, uint32_t Offset,
276  const DWARFContext &Ctx, const DWARFUnit *U,
277  std::function<void(Error)> RecoverableErrorCallback);
278 
279  /// Helper to allow for parsing of an entire .debug_line section in sequence.
281  public:
284  using LineToUnitMap = std::map<uint64_t, DWARFUnit *>;
285 
287  tu_range TUs);
288 
289  /// Get the next line table from the section. Report any issues via the
290  /// callbacks.
291  ///
292  /// \param RecoverableErrorCallback - any issues that don't prevent further
293  /// parsing of the table will be reported through this callback.
294  /// \param UnrecoverableErrorCallback - any issues that prevent further
295  /// parsing of the table will be reported through this callback.
296  /// \param OS - if not null, the parser will print information about the
297  /// table as it parses it.
298  LineTable
299  parseNext(
300  function_ref<void(Error)> RecoverableErrorCallback,
301  function_ref<void(Error)> UnrecoverableErrorCallback,
302  raw_ostream *OS = nullptr);
303 
304  /// Skip the current line table and go to the following line table (if
305  /// present) immediately.
306  ///
307  /// \param ErrorCallback - report any prologue parsing issues via this
308  /// callback.
309  void skip(function_ref<void(Error)> ErrorCallback);
310 
311  /// Indicates if the parser has parsed as much as possible.
312  ///
313  /// \note Certain problems with the line table structure might mean that
314  /// parsing stops before the end of the section is reached.
315  bool done() const { return Done; }
316 
317  /// Get the offset the parser has reached.
318  uint32_t getOffset() const { return Offset; }
319 
320  private:
321  DWARFUnit *prepareToParse(uint32_t Offset);
322  void moveToNextTable(uint32_t OldOffset, const Prologue &P);
323 
324  LineToUnitMap LineToUnit;
325 
326  DWARFDataExtractor &DebugLineData;
327  const DWARFContext &Context;
328  uint32_t Offset = 0;
329  bool Done = false;
330  };
331 
332 private:
333  struct ParsingState {
334  ParsingState(struct LineTable *LT);
335 
336  void resetRowAndSequence();
337  void appendRowToMatrix(uint32_t Offset);
338 
339  /// Line table we're currently parsing.
340  struct LineTable *LineTable;
341  /// The row number that starts at zero for the prologue, and increases for
342  /// each row added to the matrix.
343  unsigned RowNumber = 0;
344  struct Row Row;
345  struct Sequence Sequence;
346  };
347 
348  using LineTableMapTy = std::map<uint32_t, LineTable>;
349  using LineTableIter = LineTableMapTy::iterator;
350  using LineTableConstIter = LineTableMapTy::const_iterator;
351 
352  LineTableMapTy LineTableMap;
353 };
354 
355 } // end namespace llvm
356 
357 #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:494
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:24
Various leaf nodes.
Definition: ISDOpcodes.h:60
std::vector< Sequence > SequenceVector
uint32_t sizeofTotalLength() const
static bool orderByAddress(const Row &LHS, const Row &RHS)
uint32_t getLength() const
Length of the prologue in bytes.
uint32_t getStatementTableLength() const
Length of the line table data in bytes (not including the prologue).
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:111
uint32_t Line
An unsigned integer indicating a source line number.
void skip(CollectionType &C)
Definition: YAMLParser.h:389
const dwarf::FormParams getFormParams() const
std::vector< DWARFFormValue > IncludeDirectories
A format-neutral container for source line information.
Definition: DIContext.h:31
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.
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
uint64_t Address
The program-counter value corresponding to a machine instruction generated by the compiler...
Tagged union holding either a T or a Error.
Definition: CachePruning.h:23
uint8_t LineRange
This parameter affects the meaning of the special opcodes. See below.
uint8_t OpcodeBase
The number assigned to the first special opcode.
llvm::iterator_range< typename UnitVector::iterator > iterator_range
Definition: DWARFUnit.h:120
uint64_t TotalLength
The size in bytes of the statement information for this compilation unit (not including the total_len...
Expected< const LineTable * > getOrParseLineTable(DWARFDataExtractor &DebugLineData, uint32_t Offset, const DWARFContext &Ctx, const DWARFUnit *U, std::function< void(Error)> RecoverableErrorCallback)
Container for dump options that control which debug information will be dumped.
Definition: DIContext.h:154
#define P(N)
void dump(const SparseBitVector< ElementSize > &LHS, raw_ostream &out)
uint8_t SegSelectorSize
In v5, size in bytes of a segment selector.
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...
llvm::Expected< Value > parse(llvm::StringRef JSON)
Parses the provided JSON source, or returns a ParseError.
Definition: JSON.cpp:505
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...
bool containsPC(uint64_t PC) const
uint16_t Column
An unsigned integer indicating a column number within a source line.
std::map< uint64_t, DWARFUnit * > LineToUnitMap
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:59
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.
static void clear(coro::Shape &Shape)
Definition: Coroutines.cpp:212
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
static bool orderByLowPC(const Sequence &LHS, const Sequence &RHS)
Sequence
A sequence of states that a pointer may go through in which an objc_retain and objc_release are actua...
Definition: PtrState.h:41
uint32_t Size
Definition: Profile.cpp:47
uint8_t DefaultIsStmt
The initial value of theis_stmtregister.
const unsigned Kind
DwarfFormat Format
Definition: Dwarf.h:497
int8_t LineBase
This parameter affects the meaning of the special opcodes. See below.
const LineTable * getLineTable(uint32_t Offset) const
Lightweight error class with error context and mandatory checking.
Definition: Error.h:158
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:46
print Print MemDeps of function
LineNumberEntryFormat
Definition: Dwarf.h:242
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.
uint32_t getOffset() const
Get the offset the parser has reached.