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_LIB_DEBUGINFO_DWARFDEBUGLINE_H 11 #define LLVM_LIB_DEBUGINFO_DWARFDEBUGLINE_H 12 13 #include "llvm/DebugInfo/DIContext.h" 14 #include "llvm/DebugInfo/DWARF/DWARFRelocMap.h" 15 #include "llvm/Support/DataExtractor.h" 16 #include <map> 17 #include <string> 18 #include <vector> 19 20 namespace llvm { 21 22 class raw_ostream; 23 24 class DWARFDebugLine { 25 public: 26 DWARFDebugLine(const RelocAddrMap* LineInfoRelocMap) : RelocMap(LineInfoRelocMap) {} 27 struct FileNameEntry { 28 FileNameEntry() : Name(nullptr), DirIdx(0), ModTime(0), Length(0) {} 29 30 const char *Name; 31 uint64_t DirIdx; 32 uint64_t ModTime; 33 uint64_t Length; 34 }; 35 36 struct Prologue { 37 Prologue(); 38 39 // The size in bytes of the statement information for this compilation unit 40 // (not including the total_length field itself). 41 uint64_t TotalLength; 42 // Version identifier for the statement information format. 43 uint16_t Version; 44 // The number of bytes following the prologue_length field to the beginning 45 // of the first byte of the statement program itself. 46 uint64_t PrologueLength; 47 // The size in bytes of the smallest target machine instruction. Statement 48 // program opcodes that alter the address register first multiply their 49 // operands by this value. 50 uint8_t MinInstLength; 51 // The maximum number of individual operations that may be encoded in an 52 // instruction. 53 uint8_t MaxOpsPerInst; 54 // The initial value of theis_stmtregister. 55 uint8_t DefaultIsStmt; 56 // This parameter affects the meaning of the special opcodes. See below. 57 int8_t LineBase; 58 // This parameter affects the meaning of the special opcodes. See below. 59 uint8_t LineRange; 60 // The number assigned to the first special opcode. 61 uint8_t OpcodeBase; 62 std::vector<uint8_t> StandardOpcodeLengths; 63 std::vector<const char*> IncludeDirectories; 64 std::vector<FileNameEntry> FileNames; 65 66 bool IsDWARF64; 67 uint32_t sizeofTotalLength() const { 68 return IsDWARF64 ? 12 : 4; 69 } 70 uint32_t sizeofPrologueLength() const { 71 return IsDWARF64 ? 8 : 4; 72 } 73 74 // Length of the prologue in bytes. 75 uint32_t getLength() const { 76 return PrologueLength + sizeofTotalLength() + sizeof(Version) + 77 sizeofPrologueLength(); 78 } 79 // Length of the line table data in bytes (not including the prologue). 80 uint32_t getStatementTableLength() const { 81 return TotalLength + sizeofTotalLength() - getLength(); 82 } 83 int32_t getMaxLineIncrementForSpecialOpcode() const { 84 return LineBase + (int8_t)LineRange - 1; 85 } 86 87 void clear(); 88 void dump(raw_ostream &OS) const; 89 bool parse(DataExtractor debug_line_data, uint32_t *offset_ptr); 90 }; 91 92 // Standard .debug_line state machine structure. 93 struct Row { 94 explicit Row(bool default_is_stmt = false); 95 96 /// Called after a row is appended to the matrix. 97 void postAppend(); 98 void reset(bool default_is_stmt); 99 void dump(raw_ostream &OS) const; 100 101 static bool orderByAddress(const Row& LHS, const Row& RHS) { 102 return LHS.Address < RHS.Address; 103 } 104 105 // The program-counter value corresponding to a machine instruction 106 // generated by the compiler. 107 uint64_t Address; 108 // An unsigned integer indicating a source line number. Lines are numbered 109 // beginning at 1. The compiler may emit the value 0 in cases where an 110 // instruction cannot be attributed to any source line. 111 uint32_t Line; 112 // An unsigned integer indicating a column number within a source line. 113 // Columns are numbered beginning at 1. The value 0 is reserved to indicate 114 // that a statement begins at the 'left edge' of the line. 115 uint16_t Column; 116 // An unsigned integer indicating the identity of the source file 117 // corresponding to a machine instruction. 118 uint16_t File; 119 // An unsigned integer whose value encodes the applicable instruction set 120 // architecture for the current instruction. 121 uint8_t Isa; 122 // An unsigned integer representing the DWARF path discriminator value 123 // for this location. 124 uint32_t Discriminator; 125 // A boolean indicating that the current instruction is the beginning of a 126 // statement. 127 uint8_t IsStmt:1, 128 // A boolean indicating that the current instruction is the 129 // beginning of a basic block. 130 BasicBlock:1, 131 // A boolean indicating that the current address is that of the 132 // first byte after the end of a sequence of target machine 133 // instructions. 134 EndSequence:1, 135 // A boolean indicating that the current address is one (of possibly 136 // many) where execution should be suspended for an entry breakpoint 137 // of a function. 138 PrologueEnd:1, 139 // A boolean indicating that the current address is one (of possibly 140 // many) where execution should be suspended for an exit breakpoint 141 // of a function. 142 EpilogueBegin:1; 143 }; 144 145 // Represents a series of contiguous machine instructions. Line table for each 146 // compilation unit may consist of multiple sequences, which are not 147 // guaranteed to be in the order of ascending instruction address. 148 struct Sequence { 149 // Sequence describes instructions at address range [LowPC, HighPC) 150 // and is described by line table rows [FirstRowIndex, LastRowIndex). 151 uint64_t LowPC; 152 uint64_t HighPC; 153 unsigned FirstRowIndex; 154 unsigned LastRowIndex; 155 bool Empty; 156 157 Sequence(); 158 void reset(); 159 160 static bool orderByLowPC(const Sequence& LHS, const Sequence& RHS) { 161 return LHS.LowPC < RHS.LowPC; 162 } 163 bool isValid() const { 164 return !Empty && (LowPC < HighPC) && (FirstRowIndex < LastRowIndex); 165 } 166 bool containsPC(uint64_t pc) const { 167 return (LowPC <= pc && pc < HighPC); 168 } 169 }; 170 171 struct LineTable { 172 LineTable(); 173 174 // Represents an invalid row 175 const uint32_t UnknownRowIndex = UINT32_MAX; 176 177 void appendRow(const DWARFDebugLine::Row &R) { 178 Rows.push_back(R); 179 } 180 void appendSequence(const DWARFDebugLine::Sequence &S) { 181 Sequences.push_back(S); 182 } 183 184 // Returns the index of the row with file/line info for a given address, 185 // or UnknownRowIndex if there is no such row. 186 uint32_t lookupAddress(uint64_t address) const; 187 188 bool lookupAddressRange(uint64_t address, uint64_t size, 189 std::vector<uint32_t> &result) const; 190 191 // Extracts filename by its index in filename table in prologue. 192 // Returns true on success. 193 bool getFileNameByIndex(uint64_t FileIndex, const char *CompDir, 194 DILineInfoSpecifier::FileLineInfoKind Kind, 195 std::string &Result) const; 196 197 // Fills the Result argument with the file and line information 198 // corresponding to Address. Returns true on success. 199 bool getFileLineInfoForAddress(uint64_t Address, const char *CompDir, 200 DILineInfoSpecifier::FileLineInfoKind Kind, 201 DILineInfo &Result) const; 202 203 void dump(raw_ostream &OS) const; 204 void clear(); 205 206 /// Parse prologue and all rows. 207 bool parse(DataExtractor debug_line_data, const RelocAddrMap *RMap, 208 uint32_t *offset_ptr); 209 210 struct Prologue Prologue; 211 typedef std::vector<Row> RowVector; 212 typedef RowVector::const_iterator RowIter; 213 typedef std::vector<Sequence> SequenceVector; 214 typedef SequenceVector::const_iterator SequenceIter; 215 RowVector Rows; 216 SequenceVector Sequences; 217 218 private: 219 uint32_t findRowInSeq(const DWARFDebugLine::Sequence &seq, 220 uint64_t address) const; 221 }; 222 223 const LineTable *getLineTable(uint32_t offset) const; 224 const LineTable *getOrParseLineTable(DataExtractor debug_line_data, 225 uint32_t offset); 226 227 private: 228 struct ParsingState { 229 ParsingState(struct LineTable *LT); 230 231 void resetRowAndSequence(); 232 void appendRowToMatrix(uint32_t offset); 233 234 // Line table we're currently parsing. 235 struct LineTable *LineTable; 236 // The row number that starts at zero for the prologue, and increases for 237 // each row added to the matrix. 238 unsigned RowNumber; 239 struct Row Row; 240 struct Sequence Sequence; 241 }; 242 243 typedef std::map<uint32_t, LineTable> LineTableMapTy; 244 typedef LineTableMapTy::iterator LineTableIter; 245 typedef LineTableMapTy::const_iterator LineTableConstIter; 246 247 const RelocAddrMap *RelocMap; 248 LineTableMapTy LineTableMap; 249 }; 250 } 251 252 #endif 253
