From 1ea858937c0a2513b1d042c4baf83fd879beebba Mon Sep 17 00:00:00 2001 From: Alexey Samsonov Date: Wed, 30 Apr 2014 00:09:19 +0000 Subject: [DWARF parser] Cleanup code in DWARFDebugLine. Streamline parsing and dumping line tables: Prefer composition to multiple inheritance in DWARFDebugLine::ParsingState. Get rid of the weird concept of "DumpingState" structure. was: DWARFDebugLine::DumpingState state(OS); DWARFDebugLine::parseStatementTable(..., state); now: DWARFDebugLine::LineTable LineTable; LineTable.parse(...); LineTable.dump(OS); No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207599 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/DebugInfo/DWARFDebugLine.cpp | 173 +++++++++++++++++++-------------------- 1 file changed, 85 insertions(+), 88 deletions(-) (limited to 'lib/DebugInfo/DWARFDebugLine.cpp') diff --git a/lib/DebugInfo/DWARFDebugLine.cpp b/lib/DebugInfo/DWARFDebugLine.cpp index 8ca7ec18d2..a5261d7644 100644 --- a/lib/DebugInfo/DWARFDebugLine.cpp +++ b/lib/DebugInfo/DWARFDebugLine.cpp @@ -192,50 +192,34 @@ void DWARFDebugLine::LineTable::clear() { Sequences.clear(); } -DWARFDebugLine::State::~State() {} +DWARFDebugLine::ParsingState::ParsingState(struct LineTable *LT) + : LineTable(LT), RowNumber(0) { + resetRowAndSequence(); +} -void DWARFDebugLine::State::appendRowToMatrix(uint32_t offset) { - if (Sequence::Empty) { - // Record the beginning of instruction sequence. - Sequence::Empty = false; - Sequence::LowPC = Address; - Sequence::FirstRowIndex = row; - } - ++row; // Increase the row number. - LineTable::appendRow(*this); - if (EndSequence) { - // Record the end of instruction sequence. - Sequence::HighPC = Address; - Sequence::LastRowIndex = row; - if (Sequence::isValid()) - LineTable::appendSequence(*this); - Sequence::reset(); - } - Row::postAppend(); +void DWARFDebugLine::ParsingState::resetRowAndSequence() { + Row.reset(LineTable->Prologue.DefaultIsStmt); + Sequence.reset(); } -void DWARFDebugLine::State::finalize() { - row = DoneParsingLineTable; - if (!Sequence::Empty) { - fprintf(stderr, "warning: last sequence in debug line table is not" - "terminated!\n"); +void DWARFDebugLine::ParsingState::appendRowToMatrix(uint32_t offset) { + if (Sequence.Empty) { + // Record the beginning of instruction sequence. + Sequence.Empty = false; + Sequence.LowPC = Row.Address; + Sequence.FirstRowIndex = RowNumber; } - // Sort all sequences so that address lookup will work faster. - if (!Sequences.empty()) { - std::sort(Sequences.begin(), Sequences.end(), Sequence::orderByLowPC); - // Note: actually, instruction address ranges of sequences should not - // overlap (in shared objects and executables). If they do, the address - // lookup would still work, though, but result would be ambiguous. - // We don't report warning in this case. For example, - // sometimes .so compiled from multiple object files contains a few - // rudimentary sequences for address ranges [0x0, 0xsomething). + ++RowNumber; + LineTable->appendRow(Row); + if (Row.EndSequence) { + // Record the end of instruction sequence. + Sequence.HighPC = Row.Address; + Sequence.LastRowIndex = RowNumber; + if (Sequence.isValid()) + LineTable->appendSequence(Sequence); + Sequence.reset(); } -} - -DWARFDebugLine::DumpingState::~DumpingState() {} - -void DWARFDebugLine::DumpingState::finalize() { - LineTable::dump(OS); + Row.postAppend(); } const DWARFDebugLine::LineTable * @@ -251,33 +235,31 @@ DWARFDebugLine::getOrParseLineTable(DataExtractor debug_line_data, uint32_t offset) { std::pair pos = LineTableMap.insert(LineTableMapTy::value_type(offset, LineTable())); + LineTable *LT = &pos.first->second; if (pos.second) { - // Parse and cache the line table for at this offset. - State state; - if (!parseStatementTable(debug_line_data, RelocMap, &offset, state)) + if (!LT->parse(debug_line_data, RelocMap, &offset)) return nullptr; - pos.first->second = state; } - return &pos.first->second; + return LT; } -bool DWARFDebugLine::parseStatementTable(DataExtractor debug_line_data, - const RelocAddrMap *RMap, - uint32_t *offset_ptr, State &state) { +bool DWARFDebugLine::LineTable::parse(DataExtractor debug_line_data, + const RelocAddrMap *RMap, + uint32_t *offset_ptr) { const uint32_t debug_line_offset = *offset_ptr; - Prologue *prologue = &state.Prologue; + clear(); - if (!prologue->parse(debug_line_data, offset_ptr)) { + if (!Prologue.parse(debug_line_data, offset_ptr)) { // Restore our offset and return false to indicate failure! *offset_ptr = debug_line_offset; return false; } - const uint32_t end_offset = debug_line_offset + prologue->TotalLength + - sizeof(prologue->TotalLength); + const uint32_t end_offset = debug_line_offset + Prologue.TotalLength + + sizeof(Prologue.TotalLength); - state.reset(); + ParsingState State(this); while (*offset_ptr < end_offset) { uint8_t opcode = debug_line_data.getU8(offset_ptr); @@ -299,9 +281,9 @@ bool DWARFDebugLine::parseStatementTable(DataExtractor debug_line_data, // with a DW_LNE_end_sequence instruction which creates a row whose // address is that of the byte after the last target machine instruction // of the sequence. - state.EndSequence = true; - state.appendRowToMatrix(*offset_ptr); - state.reset(); + State.Row.EndSequence = true; + State.appendRowToMatrix(*offset_ptr); + State.resetRowAndSequence(); break; case DW_LNE_set_address: @@ -316,9 +298,10 @@ bool DWARFDebugLine::parseStatementTable(DataExtractor debug_line_data, RelocAddrMap::const_iterator AI = RMap->find(*offset_ptr); if (AI != RMap->end()) { const std::pair &R = AI->second; - state.Address = debug_line_data.getAddress(offset_ptr) + R.second; + State.Row.Address = + debug_line_data.getAddress(offset_ptr) + R.second; } else - state.Address = debug_line_data.getAddress(offset_ptr); + State.Row.Address = debug_line_data.getAddress(offset_ptr); } break; @@ -349,12 +332,12 @@ bool DWARFDebugLine::parseStatementTable(DataExtractor debug_line_data, fileEntry.DirIdx = debug_line_data.getULEB128(offset_ptr); fileEntry.ModTime = debug_line_data.getULEB128(offset_ptr); fileEntry.Length = debug_line_data.getULEB128(offset_ptr); - prologue->FileNames.push_back(fileEntry); + Prologue.FileNames.push_back(fileEntry); } break; case DW_LNE_set_discriminator: - state.Discriminator = debug_line_data.getULEB128(offset_ptr); + State.Row.Discriminator = debug_line_data.getULEB128(offset_ptr); break; default: @@ -363,52 +346,52 @@ bool DWARFDebugLine::parseStatementTable(DataExtractor debug_line_data, (*offset_ptr) += arg_size; break; } - } else if (opcode < prologue->OpcodeBase) { + } else if (opcode < Prologue.OpcodeBase) { switch (opcode) { // Standard Opcodes case DW_LNS_copy: // Takes no arguments. Append a row to the matrix using the // current values of the state-machine registers. Then set // the basic_block register to false. - state.appendRowToMatrix(*offset_ptr); + State.appendRowToMatrix(*offset_ptr); break; case DW_LNS_advance_pc: // Takes a single unsigned LEB128 operand, multiplies it by the // min_inst_length field of the prologue, and adds the // result to the address register of the state machine. - state.Address += debug_line_data.getULEB128(offset_ptr) * - prologue->MinInstLength; + State.Row.Address += + debug_line_data.getULEB128(offset_ptr) * Prologue.MinInstLength; break; case DW_LNS_advance_line: // Takes a single signed LEB128 operand and adds that value to // the line register of the state machine. - state.Line += debug_line_data.getSLEB128(offset_ptr); + State.Row.Line += debug_line_data.getSLEB128(offset_ptr); break; case DW_LNS_set_file: // Takes a single unsigned LEB128 operand and stores it in the file // register of the state machine. - state.File = debug_line_data.getULEB128(offset_ptr); + State.Row.File = debug_line_data.getULEB128(offset_ptr); break; case DW_LNS_set_column: // Takes a single unsigned LEB128 operand and stores it in the // column register of the state machine. - state.Column = debug_line_data.getULEB128(offset_ptr); + State.Row.Column = debug_line_data.getULEB128(offset_ptr); break; case DW_LNS_negate_stmt: // Takes no arguments. Set the is_stmt register of the state // machine to the logical negation of its current value. - state.IsStmt = !state.IsStmt; + State.Row.IsStmt = !State.Row.IsStmt; break; case DW_LNS_set_basic_block: // Takes no arguments. Set the basic_block register of the // state machine to true - state.BasicBlock = true; + State.Row.BasicBlock = true; break; case DW_LNS_const_add_pc: @@ -424,10 +407,10 @@ bool DWARFDebugLine::parseStatementTable(DataExtractor debug_line_data, // than twice that range will it need to use both DW_LNS_advance_pc // and a special opcode, requiring three or more bytes. { - uint8_t adjust_opcode = 255 - prologue->OpcodeBase; - uint64_t addr_offset = (adjust_opcode / prologue->LineRange) * - prologue->MinInstLength; - state.Address += addr_offset; + uint8_t adjust_opcode = 255 - Prologue.OpcodeBase; + uint64_t addr_offset = + (adjust_opcode / Prologue.LineRange) * Prologue.MinInstLength; + State.Row.Address += addr_offset; } break; @@ -441,25 +424,25 @@ bool DWARFDebugLine::parseStatementTable(DataExtractor debug_line_data, // judge when the computation of a special opcode overflows and // requires the use of DW_LNS_advance_pc. Such assemblers, however, // can use DW_LNS_fixed_advance_pc instead, sacrificing compression. - state.Address += debug_line_data.getU16(offset_ptr); + State.Row.Address += debug_line_data.getU16(offset_ptr); break; case DW_LNS_set_prologue_end: // Takes no arguments. Set the prologue_end register of the // state machine to true - state.PrologueEnd = true; + State.Row.PrologueEnd = true; break; case DW_LNS_set_epilogue_begin: // Takes no arguments. Set the basic_block register of the // state machine to true - state.EpilogueBegin = true; + State.Row.EpilogueBegin = true; break; case DW_LNS_set_isa: // Takes a single unsigned LEB128 operand and stores it in the // column register of the state machine. - state.Isa = debug_line_data.getULEB128(offset_ptr); + State.Row.Isa = debug_line_data.getULEB128(offset_ptr); break; default: @@ -467,9 +450,9 @@ bool DWARFDebugLine::parseStatementTable(DataExtractor debug_line_data, // of such opcodes because they are specified in the prologue // as a multiple of LEB128 operands for each opcode. { - assert(opcode - 1U < prologue->StandardOpcodeLengths.size()); - uint8_t opcode_length = prologue->StandardOpcodeLengths[opcode - 1]; - for (uint8_t i=0; iOpcodeBase; - uint64_t addr_offset = (adjust_opcode / prologue->LineRange) * - prologue->MinInstLength; - int32_t line_offset = prologue->LineBase + - (adjust_opcode % prologue->LineRange); - state.Line += line_offset; - state.Address += addr_offset; - state.appendRowToMatrix(*offset_ptr); + uint8_t adjust_opcode = opcode - Prologue.OpcodeBase; + uint64_t addr_offset = + (adjust_opcode / Prologue.LineRange) * Prologue.MinInstLength; + int32_t line_offset = + Prologue.LineBase + (adjust_opcode % Prologue.LineRange); + State.Row.Line += line_offset; + State.Row.Address += addr_offset; + State.appendRowToMatrix(*offset_ptr); } } - state.finalize(); + if (!State.Sequence.Empty) { + fprintf(stderr, "warning: last sequence in debug line table is not" + "terminated!\n"); + } + + // Sort all sequences so that address lookup will work faster. + if (!Sequences.empty()) { + std::sort(Sequences.begin(), Sequences.end(), Sequence::orderByLowPC); + // Note: actually, instruction address ranges of sequences should not + // overlap (in shared objects and executables). If they do, the address + // lookup would still work, though, but result would be ambiguous. + // We don't report warning in this case. For example, + // sometimes .so compiled from multiple object files contains a few + // rudimentary sequences for address ranges [0x0, 0xsomething). + } return end_offset; } -- cgit v1.2.3