//===-- DWARFDebugLine.cpp --------------------------------------*- C++ -*-===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// #include "DWARFDebugLine.h" //#define ENABLE_DEBUG_PRINTF // DO NOT LEAVE THIS DEFINED: DEBUG ONLY!!! #include #include "lldb/Core/FileSpecList.h" #include "lldb/Core/Module.h" #include "lldb/Host/Host.h" #include "lldb/Utility/Log.h" #include "lldb/Utility/Timer.h" #include "LogChannelDWARF.h" #include "SymbolFileDWARF.h" using namespace lldb; using namespace lldb_private; using namespace std; //---------------------------------------------------------------------- // Parse // // Parse all information in the debug_line_data into an internal // representation. //---------------------------------------------------------------------- void DWARFDebugLine::Parse(const DWARFDataExtractor &debug_line_data) { m_lineTableMap.clear(); lldb::offset_t offset = 0; LineTable::shared_ptr line_table_sp(new LineTable); while (debug_line_data.ValidOffset(offset)) { const lldb::offset_t debug_line_offset = offset; if (line_table_sp.get() == NULL) break; if (ParseStatementTable(debug_line_data, &offset, line_table_sp.get(), nullptr)) { // Make sure we don't don't loop infinitely if (offset <= debug_line_offset) break; // DEBUG_PRINTF("m_lineTableMap[0x%8.8x] = line_table_sp\n", // debug_line_offset); m_lineTableMap[debug_line_offset] = line_table_sp; line_table_sp.reset(new LineTable); } else ++offset; // Try next byte in line table } } void DWARFDebugLine::ParseIfNeeded(const DWARFDataExtractor &debug_line_data) { if (m_lineTableMap.empty()) Parse(debug_line_data); } //---------------------------------------------------------------------- // DWARFDebugLine::GetLineTable //---------------------------------------------------------------------- DWARFDebugLine::LineTable::shared_ptr DWARFDebugLine::GetLineTable(const dw_offset_t offset) const { DWARFDebugLine::LineTable::shared_ptr line_table_shared_ptr; LineTableConstIter pos = m_lineTableMap.find(offset); if (pos != m_lineTableMap.end()) line_table_shared_ptr = pos->second; return line_table_shared_ptr; } //---------------------------------------------------------------------- // DumpStateToFile //---------------------------------------------------------------------- static void DumpStateToFile(dw_offset_t offset, const DWARFDebugLine::State &state, void *userData) { Log *log = (Log *)userData; if (state.row == DWARFDebugLine::State::StartParsingLineTable) { // If the row is zero we are being called with the prologue only state.prologue->Dump(log); log->PutCString("Address Line Column File"); log->PutCString("------------------ ------ ------ ------"); } else if (state.row == DWARFDebugLine::State::DoneParsingLineTable) { // Done parsing line table } else { log->Printf("0x%16.16" PRIx64 " %6u %6u %6u%s\n", state.address, state.line, state.column, state.file, state.end_sequence ? " END" : ""); } } //---------------------------------------------------------------------- // DWARFDebugLine::DumpLineTableRows //---------------------------------------------------------------------- bool DWARFDebugLine::DumpLineTableRows(Log *log, SymbolFileDWARF *dwarf2Data, dw_offset_t debug_line_offset) { const DWARFDataExtractor &debug_line_data = dwarf2Data->get_debug_line_data(); if (debug_line_offset == DW_INVALID_OFFSET) { // Dump line table to a single file only debug_line_offset = 0; while (debug_line_data.ValidOffset(debug_line_offset)) debug_line_offset = DumpStatementTable(log, debug_line_data, debug_line_offset); } else { // Dump line table to a single file only DumpStatementTable(log, debug_line_data, debug_line_offset); } return false; } //---------------------------------------------------------------------- // DWARFDebugLine::DumpStatementTable //---------------------------------------------------------------------- dw_offset_t DWARFDebugLine::DumpStatementTable(Log *log, const DWARFDataExtractor &debug_line_data, const dw_offset_t debug_line_offset) { if (debug_line_data.ValidOffset(debug_line_offset)) { lldb::offset_t offset = debug_line_offset; log->Printf("--------------------------------------------------------------" "--------\n" "debug_line[0x%8.8x]\n" "--------------------------------------------------------------" "--------\n", debug_line_offset); if (ParseStatementTable(debug_line_data, &offset, DumpStateToFile, log, nullptr)) return offset; else return debug_line_offset + 1; // Skip to next byte in .debug_line section } return DW_INVALID_OFFSET; } //---------------------------------------------------------------------- // DumpOpcodes //---------------------------------------------------------------------- bool DWARFDebugLine::DumpOpcodes(Log *log, SymbolFileDWARF *dwarf2Data, dw_offset_t debug_line_offset, uint32_t dump_flags) { const DWARFDataExtractor &debug_line_data = dwarf2Data->get_debug_line_data(); if (debug_line_data.GetByteSize() == 0) { log->Printf("< EMPTY >\n"); return false; } if (debug_line_offset == DW_INVALID_OFFSET) { // Dump line table to a single file only debug_line_offset = 0; while (debug_line_data.ValidOffset(debug_line_offset)) debug_line_offset = DumpStatementOpcodes(log, debug_line_data, debug_line_offset, dump_flags); } else { // Dump line table to a single file only DumpStatementOpcodes(log, debug_line_data, debug_line_offset, dump_flags); } return false; } //---------------------------------------------------------------------- // DumpStatementOpcodes //---------------------------------------------------------------------- dw_offset_t DWARFDebugLine::DumpStatementOpcodes( Log *log, const DWARFDataExtractor &debug_line_data, const dw_offset_t debug_line_offset, uint32_t flags) { lldb::offset_t offset = debug_line_offset; if (debug_line_data.ValidOffset(offset)) { Prologue prologue; if (ParsePrologue(debug_line_data, &offset, &prologue)) { log->PutCString("--------------------------------------------------------" "--------------"); log->Printf("debug_line[0x%8.8x]", debug_line_offset); log->PutCString("--------------------------------------------------------" "--------------\n"); prologue.Dump(log); } else { offset = debug_line_offset; log->Printf("0x%8.8" PRIx64 ": skipping pad byte %2.2x", offset, debug_line_data.GetU8(&offset)); return offset; } Row row(prologue.default_is_stmt); const dw_offset_t end_offset = debug_line_offset + prologue.total_length + sizeof(prologue.total_length); assert(debug_line_data.ValidOffset(end_offset - 1)); while (offset < end_offset) { const uint32_t op_offset = offset; uint8_t opcode = debug_line_data.GetU8(&offset); switch (opcode) { case 0: // Extended Opcodes always start with a zero opcode followed by { // a uleb128 length so you can skip ones you don't know about dw_offset_t ext_offset = offset; dw_uleb128_t len = debug_line_data.GetULEB128(&offset); dw_offset_t arg_size = len - (offset - ext_offset); uint8_t sub_opcode = debug_line_data.GetU8(&offset); // if (verbose) // log->Printf( "Extended: <%u> %2.2x ", len, // sub_opcode); switch (sub_opcode) { case DW_LNE_end_sequence: log->Printf("0x%8.8x: DW_LNE_end_sequence", op_offset); row.Dump(log); row.Reset(prologue.default_is_stmt); break; case DW_LNE_set_address: { row.address = debug_line_data.GetMaxU64(&offset, arg_size); log->Printf("0x%8.8x: DW_LNE_set_address (0x%" PRIx64 ")", op_offset, row.address); } break; case DW_LNE_define_file: { FileNameEntry fileEntry; fileEntry.name = debug_line_data.GetCStr(&offset); fileEntry.dir_idx = debug_line_data.GetULEB128(&offset); fileEntry.mod_time = debug_line_data.GetULEB128(&offset); fileEntry.length = debug_line_data.GetULEB128(&offset); log->Printf("0x%8.8x: DW_LNE_define_file('%s', dir=%i, " "mod_time=0x%8.8x, length=%i )", op_offset, fileEntry.name, fileEntry.dir_idx, fileEntry.mod_time, fileEntry.length); prologue.file_names.push_back(fileEntry); } break; case DW_LNE_set_discriminator: { uint64_t discriminator = debug_line_data.GetULEB128(&offset); log->Printf("0x%8.8x: DW_LNE_set_discriminator (0x%" PRIx64 ")", op_offset, discriminator); } break; default: log->Printf("0x%8.8x: DW_LNE_??? (%2.2x) - Skipping unknown upcode", op_offset, opcode); // Length doesn't include the zero opcode byte or the length itself, // but it does include the sub_opcode, so we have to adjust for that // below offset += arg_size; break; } } break; // Standard Opcodes case DW_LNS_copy: log->Printf("0x%8.8x: DW_LNS_copy", op_offset); row.Dump(log); break; case DW_LNS_advance_pc: { dw_uleb128_t addr_offset_n = debug_line_data.GetULEB128(&offset); dw_uleb128_t addr_offset = addr_offset_n * prologue.min_inst_length; log->Printf("0x%8.8x: DW_LNS_advance_pc (0x%x)", op_offset, addr_offset); row.address += addr_offset; } break; case DW_LNS_advance_line: { dw_sleb128_t line_offset = debug_line_data.GetSLEB128(&offset); log->Printf("0x%8.8x: DW_LNS_advance_line (%i)", op_offset, line_offset); row.line += line_offset; } break; case DW_LNS_set_file: row.file = debug_line_data.GetULEB128(&offset); log->Printf("0x%8.8x: DW_LNS_set_file (%u)", op_offset, row.file); break; case DW_LNS_set_column: row.column = debug_line_data.GetULEB128(&offset); log->Printf("0x%8.8x: DW_LNS_set_column (%u)", op_offset, row.column); break; case DW_LNS_negate_stmt: row.is_stmt = !row.is_stmt; log->Printf("0x%8.8x: DW_LNS_negate_stmt", op_offset); break; case DW_LNS_set_basic_block: row.basic_block = true; log->Printf("0x%8.8x: DW_LNS_set_basic_block", op_offset); break; case DW_LNS_const_add_pc: { uint8_t adjust_opcode = 255 - prologue.opcode_base; dw_addr_t addr_offset = (adjust_opcode / prologue.line_range) * prologue.min_inst_length; log->Printf("0x%8.8x: DW_LNS_const_add_pc (0x%8.8" PRIx64 ")", op_offset, addr_offset); row.address += addr_offset; } break; case DW_LNS_fixed_advance_pc: { uint16_t pc_offset = debug_line_data.GetU16(&offset); log->Printf("0x%8.8x: DW_LNS_fixed_advance_pc (0x%4.4x)", op_offset, pc_offset); row.address += pc_offset; } break; case DW_LNS_set_prologue_end: row.prologue_end = true; log->Printf("0x%8.8x: DW_LNS_set_prologue_end", op_offset); break; case DW_LNS_set_epilogue_begin: row.epilogue_begin = true; log->Printf("0x%8.8x: DW_LNS_set_epilogue_begin", op_offset); break; case DW_LNS_set_isa: row.isa = debug_line_data.GetULEB128(&offset); log->Printf("0x%8.8x: DW_LNS_set_isa (%u)", op_offset, row.isa); break; // Special Opcodes default: if (opcode < prologue.opcode_base) { // We have an opcode that this parser doesn't know about, skip the // number of ULEB128 numbers that is says to skip in the prologue's // standard_opcode_lengths array uint8_t n = prologue.standard_opcode_lengths[opcode - 1]; log->Printf("0x%8.8x: Special : Unknown skipping %u ULEB128 values.", op_offset, n); while (n > 0) { debug_line_data.GetULEB128(&offset); --n; } } else { uint8_t adjust_opcode = opcode - prologue.opcode_base; dw_addr_t addr_offset = (adjust_opcode / prologue.line_range) * prologue.min_inst_length; int32_t line_offset = prologue.line_base + (adjust_opcode % prologue.line_range); log->Printf("0x%8.8x: address += 0x%" PRIx64 ", line += %i\n", op_offset, (uint64_t)addr_offset, line_offset); row.address += addr_offset; row.line += line_offset; row.Dump(log); } break; } } return end_offset; } return DW_INVALID_OFFSET; } //---------------------------------------------------------------------- // Parse // // Parse the entire line table contents calling callback each time a new // prologue is parsed and every time a new row is to be added to the line // table. //---------------------------------------------------------------------- void DWARFDebugLine::Parse(const DWARFDataExtractor &debug_line_data, DWARFDebugLine::State::Callback callback, void *userData) { lldb::offset_t offset = 0; if (debug_line_data.ValidOffset(offset)) { if (!ParseStatementTable(debug_line_data, &offset, callback, userData, nullptr)) ++offset; // Skip to next byte in .debug_line section } } namespace { struct EntryDescriptor { dw_sleb128_t code; dw_sleb128_t form; }; static std::vector ReadDescriptors(const DWARFDataExtractor &debug_line_data, lldb::offset_t *offset_ptr) { std::vector ret; uint8_t n = debug_line_data.GetU8(offset_ptr); for (uint8_t i = 0; i < n; ++i) { EntryDescriptor ent; ent.code = debug_line_data.GetULEB128(offset_ptr); ent.form = debug_line_data.GetULEB128(offset_ptr); ret.push_back(ent); } return ret; } } // namespace //---------------------------------------------------------------------- // DWARFDebugLine::ParsePrologue //---------------------------------------------------------------------- bool DWARFDebugLine::ParsePrologue(const DWARFDataExtractor &debug_line_data, lldb::offset_t *offset_ptr, Prologue *prologue, DWARFUnit *dwarf_cu) { const lldb::offset_t prologue_offset = *offset_ptr; // DEBUG_PRINTF("0x%8.8x: ParsePrologue()\n", *offset_ptr); prologue->Clear(); uint32_t i; const char *s; prologue->total_length = debug_line_data.GetDWARFInitialLength(offset_ptr); prologue->version = debug_line_data.GetU16(offset_ptr); if (prologue->version < 2 || prologue->version > 5) return false; if (prologue->version >= 5) { prologue->address_size = debug_line_data.GetU8(offset_ptr); prologue->segment_selector_size = debug_line_data.GetU8(offset_ptr); } prologue->prologue_length = debug_line_data.GetDWARFOffset(offset_ptr); const lldb::offset_t end_prologue_offset = prologue->prologue_length + *offset_ptr; prologue->min_inst_length = debug_line_data.GetU8(offset_ptr); if (prologue->version >= 4) prologue->maximum_operations_per_instruction = debug_line_data.GetU8(offset_ptr); else prologue->maximum_operations_per_instruction = 1; prologue->default_is_stmt = debug_line_data.GetU8(offset_ptr); prologue->line_base = debug_line_data.GetU8(offset_ptr); prologue->line_range = debug_line_data.GetU8(offset_ptr); prologue->opcode_base = debug_line_data.GetU8(offset_ptr); prologue->standard_opcode_lengths.reserve(prologue->opcode_base - 1); for (i = 1; i < prologue->opcode_base; ++i) { uint8_t op_len = debug_line_data.GetU8(offset_ptr); prologue->standard_opcode_lengths.push_back(op_len); } if (prologue->version >= 5) { std::vector dirEntryFormatV = ReadDescriptors(debug_line_data, offset_ptr); uint8_t dirCount = debug_line_data.GetULEB128(offset_ptr); for (int i = 0; i < dirCount; ++i) { for (EntryDescriptor &ent : dirEntryFormatV) { DWARFFormValue value(dwarf_cu, ent.form); if (ent.code != DW_LNCT_path) { if (!value.SkipValue(debug_line_data, offset_ptr)) return false; continue; } if (!value.ExtractValue(debug_line_data, offset_ptr)) return false; prologue->include_directories.push_back(value.AsCString()); } } std::vector filesEntryFormatV = ReadDescriptors(debug_line_data, offset_ptr); llvm::DenseSet> seen; uint8_t n = debug_line_data.GetULEB128(offset_ptr); for (int i = 0; i < n; ++i) { FileNameEntry entry; for (EntryDescriptor &ent : filesEntryFormatV) { DWARFFormValue value(dwarf_cu, ent.form); if (!value.ExtractValue(debug_line_data, offset_ptr)) return false; switch (ent.code) { case DW_LNCT_path: entry.name = value.AsCString(); break; case DW_LNCT_directory_index: entry.dir_idx = value.Unsigned(); break; case DW_LNCT_timestamp: entry.mod_time = value.Unsigned(); break; case DW_LNCT_size: entry.length = value.Unsigned(); break; case DW_LNCT_MD5: assert(value.Unsigned() == 16); std::uninitialized_copy_n(value.BlockData(), 16, entry.checksum.Bytes.begin()); break; default: break; } } if (seen.insert(entry.checksum.words()).second) prologue->file_names.push_back(entry); } } else { while (*offset_ptr < end_prologue_offset) { s = debug_line_data.GetCStr(offset_ptr); if (s && s[0]) prologue->include_directories.push_back(s); else break; } while (*offset_ptr < end_prologue_offset) { const char *name = debug_line_data.GetCStr(offset_ptr); if (name && name[0]) { FileNameEntry fileEntry; fileEntry.name = name; fileEntry.dir_idx = debug_line_data.GetULEB128(offset_ptr); fileEntry.mod_time = debug_line_data.GetULEB128(offset_ptr); fileEntry.length = debug_line_data.GetULEB128(offset_ptr); prologue->file_names.push_back(fileEntry); } else break; } } // XXX GNU as is broken for 64-Bit DWARF if (*offset_ptr != end_prologue_offset) { Host::SystemLog(Host::eSystemLogWarning, "warning: parsing line table prologue at 0x%8.8" PRIx64 " should have ended at 0x%8.8" PRIx64 " but it ended at 0x%8.8" PRIx64 "\n", prologue_offset, end_prologue_offset, *offset_ptr); } return end_prologue_offset; } bool DWARFDebugLine::ParseSupportFiles( const lldb::ModuleSP &module_sp, const DWARFDataExtractor &debug_line_data, const lldb_private::FileSpec &cu_comp_dir, dw_offset_t stmt_list, FileSpecList &support_files, DWARFUnit *dwarf_cu) { lldb::offset_t offset = stmt_list; Prologue prologue; if (!ParsePrologue(debug_line_data, &offset, &prologue, dwarf_cu)) { Host::SystemLog(Host::eSystemLogError, "error: parsing line table prologue " "at 0x%8.8x (parsing ended around " "0x%8.8" PRIx64 "\n", stmt_list, offset); return false; } FileSpec file_spec; std::string remapped_file; for (uint32_t file_idx = 1; prologue.GetFile(file_idx, cu_comp_dir, file_spec); ++file_idx) { if (module_sp->RemapSourceFile(file_spec.GetPath(), remapped_file)) file_spec.SetFile(remapped_file, FileSpec::Style::native); support_files.Append(file_spec); } return true; } //---------------------------------------------------------------------- // ParseStatementTable // // Parse a single line table (prologue and all rows) and call the callback // function once for the prologue (row in state will be zero) and each time a // row is to be added to the line table. //---------------------------------------------------------------------- bool DWARFDebugLine::ParseStatementTable( const DWARFDataExtractor &debug_line_data, lldb::offset_t *offset_ptr, DWARFDebugLine::State::Callback callback, void *userData, DWARFUnit *dwarf_cu) { Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_LINE)); Prologue::shared_ptr prologue(new Prologue()); const dw_offset_t debug_line_offset = *offset_ptr; static Timer::Category func_cat(LLVM_PRETTY_FUNCTION); Timer scoped_timer( func_cat, "DWARFDebugLine::ParseStatementTable (.debug_line[0x%8.8x])", debug_line_offset); if (!ParsePrologue(debug_line_data, offset_ptr, prologue.get(), dwarf_cu)) { if (log) log->Error("failed to parse DWARF line table prologue"); // Restore our offset and return false to indicate failure! *offset_ptr = debug_line_offset; return false; } if (log) prologue->Dump(log); const dw_offset_t end_offset = debug_line_offset + prologue->total_length + (debug_line_data.GetDWARFSizeofInitialLength()); State state(prologue, log, callback, userData); while (*offset_ptr < end_offset) { // DEBUG_PRINTF("0x%8.8x: ", *offset_ptr); uint8_t opcode = debug_line_data.GetU8(offset_ptr); if (opcode == 0) { // Extended Opcodes always start with a zero opcode followed by a uleb128 // length so you can skip ones you don't know about lldb::offset_t ext_offset = *offset_ptr; dw_uleb128_t len = debug_line_data.GetULEB128(offset_ptr); dw_offset_t arg_size = len - (*offset_ptr - ext_offset); // DEBUG_PRINTF("Extended: <%2u> ", len); uint8_t sub_opcode = debug_line_data.GetU8(offset_ptr); switch (sub_opcode) { case DW_LNE_end_sequence: // Set the end_sequence register of the state machine to true and // append a row to the matrix using the current values of the state- // machine registers. Then reset the registers to the initial values // specified above. Every statement program sequence must end 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.end_sequence = true; state.AppendRowToMatrix(*offset_ptr); state.Reset(); break; case DW_LNE_set_address: // Takes a single relocatable address as an operand. The size of the // operand is the size appropriate to hold an address on the target // machine. Set the address register to the value given by the // relocatable address. All of the other statement program opcodes that // affect the address register add a delta to it. This instruction // stores a relocatable value into it instead. if (arg_size == 4) state.address = debug_line_data.GetU32(offset_ptr); else // arg_size == 8 state.address = debug_line_data.GetU64(offset_ptr); break; case DW_LNE_define_file: // Takes 4 arguments. The first is a null terminated string containing // a source file name. The second is an unsigned LEB128 number // representing the directory index of the directory in which the file // was found. The third is an unsigned LEB128 number representing the // time of last modification of the file. The fourth is an unsigned // LEB128 number representing the length in bytes of the file. The time // and length fields may contain LEB128(0) if the information is not // available. // // The directory index represents an entry in the include_directories // section of the statement program prologue. The index is LEB128(0) if // the file was found in the current directory of the compilation, // LEB128(1) if it was found in the first directory in the // include_directories section, and so on. The directory index is // ignored for file names that represent full path names. // // The files are numbered, starting at 1, in the order in which they // appear; the names in the prologue come before names defined by the // DW_LNE_define_file instruction. These numbers are used in the file // register of the state machine. { FileNameEntry fileEntry; fileEntry.name = debug_line_data.GetCStr(offset_ptr); fileEntry.dir_idx = debug_line_data.GetULEB128(offset_ptr); fileEntry.mod_time = debug_line_data.GetULEB128(offset_ptr); fileEntry.length = debug_line_data.GetULEB128(offset_ptr); state.prologue->file_names.push_back(fileEntry); } break; default: // Length doesn't include the zero opcode byte or the length itself, // but it does include the sub_opcode, so we have to adjust for that // below (*offset_ptr) += arg_size; break; } } else if (opcode < prologue->opcode_base) { 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); 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->min_inst_length; 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); 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); 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); 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.is_stmt = !state.is_stmt; break; case DW_LNS_set_basic_block: // Takes no arguments. Set the basic_block register of the state // machine to true state.basic_block = true; break; case DW_LNS_const_add_pc: // Takes no arguments. Add to the address register of the state machine // the address increment value corresponding to special opcode 255. The // motivation for DW_LNS_const_add_pc is this: when the statement // program needs to advance the address by a small amount, it can use a // single special opcode, which occupies a single byte. When it needs // to advance the address by up to twice the range of the last special // opcode, it can use DW_LNS_const_add_pc followed by a special opcode, // for a total of two bytes. Only if it needs to advance the address by // more 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->opcode_base; dw_addr_t addr_offset = (adjust_opcode / prologue->line_range) * prologue->min_inst_length; state.address += addr_offset; } break; case DW_LNS_fixed_advance_pc: // Takes a single uhalf operand. Add to the address register of the // state machine the value of the (unencoded) operand. This is the only // extended opcode that takes an argument that is not a variable length // number. The motivation for DW_LNS_fixed_advance_pc is this: existing // assemblers cannot emit DW_LNS_advance_pc or special opcodes because // they cannot encode LEB128 numbers or 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); break; case DW_LNS_set_prologue_end: // Takes no arguments. Set the prologue_end register of the state // machine to true state.prologue_end = true; break; case DW_LNS_set_epilogue_begin: // Takes no arguments. Set the basic_block register of the state // machine to true state.epilogue_begin = 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); break; default: // Handle any unknown standard opcodes here. We know the lengths of // such opcodes because they are specified in the prologue as a // multiple of LEB128 operands for each opcode. { uint8_t i; assert(static_cast(opcode - 1) < prologue->standard_opcode_lengths.size()); const uint8_t opcode_length = prologue->standard_opcode_lengths[opcode - 1]; for (i = 0; i < opcode_length; ++i) debug_line_data.Skip_LEB128(offset_ptr); } break; } } else { // Special Opcodes // A special opcode value is chosen based on the amount that needs // to be added to the line and address registers. The maximum line // increment for a special opcode is the value of the line_base field in // the header, plus the value of the line_range field, minus 1 (line base // + line range - 1). If the desired line increment is greater than the // maximum line increment, a standard opcode must be used instead of a // special opcode. The "address advance" is calculated by dividing the // desired address increment by the minimum_instruction_length field from // the header. The special opcode is then calculated using the following // formula: // // opcode = (desired line increment - line_base) + (line_range * address // advance) + opcode_base // // If the resulting opcode is greater than 255, a standard opcode must be // used instead. // // To decode a special opcode, subtract the opcode_base from the opcode // itself to give the adjusted opcode. The amount to increment the // address register is the result of the adjusted opcode divided by the // line_range multiplied by the minimum_instruction_length field from the // header. That is: // // address increment = (adjusted opcode / line_range) * // minimum_instruction_length // // The amount to increment the line register is the line_base plus the // result of the adjusted opcode modulo the line_range. That is: // // line increment = line_base + (adjusted opcode % line_range) uint8_t adjust_opcode = opcode - prologue->opcode_base; dw_addr_t addr_offset = (adjust_opcode / prologue->line_range) * prologue->min_inst_length; int32_t line_offset = prologue->line_base + (adjust_opcode % prologue->line_range); state.line += line_offset; state.address += addr_offset; state.AppendRowToMatrix(*offset_ptr); } } state.Finalize(*offset_ptr); return end_offset; } //---------------------------------------------------------------------- // ParseStatementTableCallback //---------------------------------------------------------------------- static void ParseStatementTableCallback(dw_offset_t offset, const DWARFDebugLine::State &state, void *userData) { DWARFDebugLine::LineTable *line_table = (DWARFDebugLine::LineTable *)userData; if (state.row == DWARFDebugLine::State::StartParsingLineTable) { // Just started parsing the line table, so lets keep a reference to the // prologue using the supplied shared pointer line_table->prologue = state.prologue; } else if (state.row == DWARFDebugLine::State::DoneParsingLineTable) { // Done parsing line table, nothing to do for the cleanup } else { // We have a new row, lets append it line_table->AppendRow(state); } } //---------------------------------------------------------------------- // ParseStatementTable // // Parse a line table at offset and populate the LineTable class with the // prologue and all rows. //---------------------------------------------------------------------- bool DWARFDebugLine::ParseStatementTable( const DWARFDataExtractor &debug_line_data, lldb::offset_t *offset_ptr, LineTable *line_table, DWARFUnit *dwarf_cu) { return ParseStatementTable(debug_line_data, offset_ptr, ParseStatementTableCallback, line_table, dwarf_cu); } inline bool DWARFDebugLine::Prologue::IsValid() const { return SymbolFileDWARF::SupportedVersion(version); } //---------------------------------------------------------------------- // DWARFDebugLine::Prologue::Dump //---------------------------------------------------------------------- void DWARFDebugLine::Prologue::Dump(Log *log) { uint32_t i; log->Printf("Line table prologue:"); log->Printf(" total_length: 0x%8.8x", total_length); log->Printf(" version: %u", version); log->Printf("prologue_length: 0x%8.8x", prologue_length); log->Printf("min_inst_length: %u", min_inst_length); log->Printf("default_is_stmt: %u", default_is_stmt); log->Printf(" line_base: %i", line_base); log->Printf(" line_range: %u", line_range); log->Printf(" opcode_base: %u", opcode_base); for (i = 0; i < standard_opcode_lengths.size(); ++i) { log->Printf("standard_opcode_lengths[%s] = %u", DW_LNS_value_to_name(i + 1), standard_opcode_lengths[i]); } if (!include_directories.empty()) { for (i = 0; i < include_directories.size(); ++i) { log->Printf("include_directories[%3u] = '%s'", i + 1, include_directories[i]); } } if (!file_names.empty()) { log->PutCString(" Dir Mod Time File Len File Name"); log->PutCString(" ---- ---------- ---------- " "---------------------------"); for (i = 0; i < file_names.size(); ++i) { const FileNameEntry &fileEntry = file_names[i]; log->Printf("file_names[%3u] %4u 0x%8.8x 0x%8.8x %s", i + 1, fileEntry.dir_idx, fileEntry.mod_time, fileEntry.length, fileEntry.name); } } } //---------------------------------------------------------------------- // DWARFDebugLine::ParsePrologue::Append // // Append the contents of the prologue to the binary stream buffer //---------------------------------------------------------------------- // void // DWARFDebugLine::Prologue::Append(BinaryStreamBuf& buff) const //{ // uint32_t i; // // buff.Append32(total_length); // buff.Append16(version); // buff.Append32(prologue_length); // buff.Append8(min_inst_length); // buff.Append8(default_is_stmt); // buff.Append8(line_base); // buff.Append8(line_range); // buff.Append8(opcode_base); // // for (i=0; i 0) { const uint32_t dir_idx = file_names[idx].dir_idx - 1; if (dir_idx < include_directories.size()) { file.PrependPathComponent(include_directories[dir_idx]); if (!file.IsRelative()) return true; } } if (comp_dir) file.PrependPathComponent(comp_dir); } return true; } return false; } //---------------------------------------------------------------------- // DWARFDebugLine::LineTable::Dump //---------------------------------------------------------------------- void DWARFDebugLine::LineTable::Dump(Log *log) const { if (prologue.get()) prologue->Dump(log); if (!rows.empty()) { log->PutCString("Address Line Column File ISA Flags"); log->PutCString( "------------------ ------ ------ ------ --- -------------"); Row::const_iterator pos = rows.begin(); Row::const_iterator end = rows.end(); while (pos != end) { (*pos).Dump(log); ++pos; } } } void DWARFDebugLine::LineTable::AppendRow(const DWARFDebugLine::Row &state) { rows.push_back(state); } //---------------------------------------------------------------------- // Compare function for the binary search in // DWARFDebugLine::LineTable::LookupAddress() //---------------------------------------------------------------------- static bool FindMatchingAddress(const DWARFDebugLine::Row &row1, const DWARFDebugLine::Row &row2) { return row1.address < row2.address; } //---------------------------------------------------------------------- // DWARFDebugLine::LineTable::LookupAddress //---------------------------------------------------------------------- uint32_t DWARFDebugLine::LineTable::LookupAddress(dw_addr_t address, dw_addr_t cu_high_pc) const { uint32_t index = UINT32_MAX; if (!rows.empty()) { // Use the lower_bound algorithm to perform a binary search since we know // that our line table data is ordered by address. DWARFDebugLine::Row row; row.address = address; Row::const_iterator begin_pos = rows.begin(); Row::const_iterator end_pos = rows.end(); Row::const_iterator pos = lower_bound(begin_pos, end_pos, row, FindMatchingAddress); if (pos == end_pos) { if (address < cu_high_pc) return rows.size() - 1; } else { // Rely on fact that we are using a std::vector and we can do pointer // arithmetic to find the row index (which will be one less that what we // found since it will find the first position after the current address) // since std::vector iterators are just pointers to the container type. index = pos - begin_pos; if (pos->address > address) { if (index > 0) --index; else index = UINT32_MAX; } } } return index; // Failed to find address } //---------------------------------------------------------------------- // DWARFDebugLine::Row::Row //---------------------------------------------------------------------- DWARFDebugLine::Row::Row(bool default_is_stmt) : address(0), line(1), column(0), file(1), is_stmt(default_is_stmt), basic_block(false), end_sequence(false), prologue_end(false), epilogue_begin(false), isa(0) {} //---------------------------------------------------------------------- // Called after a row is appended to the matrix //---------------------------------------------------------------------- void DWARFDebugLine::Row::PostAppend() { basic_block = false; prologue_end = false; epilogue_begin = false; } //---------------------------------------------------------------------- // DWARFDebugLine::Row::Reset //---------------------------------------------------------------------- void DWARFDebugLine::Row::Reset(bool default_is_stmt) { address = 0; line = 1; column = 0; file = 1; is_stmt = default_is_stmt; basic_block = false; end_sequence = false; prologue_end = false; epilogue_begin = false; isa = 0; } //---------------------------------------------------------------------- // DWARFDebugLine::Row::Dump //---------------------------------------------------------------------- void DWARFDebugLine::Row::Dump(Log *log) const { log->Printf("0x%16.16" PRIx64 " %6u %6u %6u %3u %s%s%s%s%s", address, line, column, file, isa, is_stmt ? " is_stmt" : "", basic_block ? " basic_block" : "", prologue_end ? " prologue_end" : "", epilogue_begin ? " epilogue_begin" : "", end_sequence ? " end_sequence" : ""); } //---------------------------------------------------------------------- // Compare function LineTable structures //---------------------------------------------------------------------- static bool AddressLessThan(const DWARFDebugLine::Row &a, const DWARFDebugLine::Row &b) { return a.address < b.address; } // Insert a row at the correct address if the addresses can be out of order // which can only happen when we are linking a line table that may have had // it's contents rearranged. void DWARFDebugLine::Row::Insert(Row::collection &state_coll, const Row &state) { // If we don't have anything yet, or if the address of the last state in our // line table is less than the current one, just append the current state if (state_coll.empty() || AddressLessThan(state_coll.back(), state)) { state_coll.push_back(state); } else { // Do a binary search for the correct entry pair range(equal_range( state_coll.begin(), state_coll.end(), state, AddressLessThan)); // If the addresses are equal, we can safely replace the previous entry // with the current one if the one it is replacing is an end_sequence // entry. We currently always place an extra end sequence when ever we exit // a valid address range for a function in case the functions get // rearranged by optimizations or by order specifications. These extra end // sequences will disappear by getting replaced with valid consecutive // entries within a compile unit if there are no gaps. if (range.first == range.second) { state_coll.insert(range.first, state); } else { if ((distance(range.first, range.second) == 1) && range.first->end_sequence == true) { *range.first = state; } else { state_coll.insert(range.second, state); } } } } void DWARFDebugLine::Row::Dump(Log *log, const Row::collection &state_coll) { std::for_each(state_coll.begin(), state_coll.end(), bind2nd(std::mem_fun_ref(&Row::Dump), log)); } //---------------------------------------------------------------------- // DWARFDebugLine::State::State //---------------------------------------------------------------------- DWARFDebugLine::State::State(Prologue::shared_ptr &p, Log *l, DWARFDebugLine::State::Callback cb, void *userData) : Row(p->default_is_stmt), prologue(p), log(l), callback(cb), callbackUserData(userData), row(StartParsingLineTable) { // Call the callback with the initial row state of zero for the prologue if (callback) callback(0, *this, callbackUserData); } //---------------------------------------------------------------------- // DWARFDebugLine::State::Reset //---------------------------------------------------------------------- void DWARFDebugLine::State::Reset() { Row::Reset(prologue->default_is_stmt); } //---------------------------------------------------------------------- // DWARFDebugLine::State::AppendRowToMatrix //---------------------------------------------------------------------- void DWARFDebugLine::State::AppendRowToMatrix(dw_offset_t offset) { // Each time we are to add an entry into the line table matrix call the // callback function so that someone can do something with the current state // of the state machine (like build a line table or dump the line table!) if (log) { if (row == 0) { log->PutCString("Address Line Column File ISA Flags"); log->PutCString( "------------------ ------ ------ ------ --- -------------"); } Dump(log); } ++row; // Increase the row number before we call our callback for a real row if (callback) callback(offset, *this, callbackUserData); PostAppend(); } //---------------------------------------------------------------------- // DWARFDebugLine::State::Finalize //---------------------------------------------------------------------- void DWARFDebugLine::State::Finalize(dw_offset_t offset) { // Call the callback with a special row state when we are done parsing a line // table row = DoneParsingLineTable; if (callback) callback(offset, *this, callbackUserData); } // void // DWARFDebugLine::AppendLineTableData //( // const DWARFDebugLine::Prologue* prologue, // const DWARFDebugLine::Row::collection& state_coll, // const uint32_t addr_size, // BinaryStreamBuf &debug_line_data //) //{ // if (state_coll.empty()) // { // // We have no entries, just make an empty line table // debug_line_data.Append8(0); // debug_line_data.Append8(1); // debug_line_data.Append8(DW_LNE_end_sequence); // } // else // { // DWARFDebugLine::Row::const_iterator pos; // Row::const_iterator end = state_coll.end(); // bool default_is_stmt = prologue->default_is_stmt; // const DWARFDebugLine::Row reset_state(default_is_stmt); // const DWARFDebugLine::Row* prev_state = &reset_state; // const int32_t max_line_increment_for_special_opcode = // prologue->MaxLineIncrementForSpecialOpcode(); // for (pos = state_coll.begin(); pos != end; ++pos) // { // const DWARFDebugLine::Row& curr_state = *pos; // int32_t line_increment = 0; // dw_addr_t addr_offset = curr_state.address - prev_state->address; // dw_addr_t addr_advance = (addr_offset) / prologue->min_inst_length; // line_increment = (int32_t)(curr_state.line - prev_state->line); // // // If our previous state was the reset state, then let's emit the // // address to keep GDB's DWARF parser happy. If we don't start each // // sequence with a DW_LNE_set_address opcode, the line table won't // // get slid properly in GDB. // // if (prev_state == &reset_state) // { // debug_line_data.Append8(0); // Extended opcode // debug_line_data.Append32_as_ULEB128(addr_size + 1); // Length of // opcode bytes // debug_line_data.Append8(DW_LNE_set_address); // debug_line_data.AppendMax64(curr_state.address, addr_size); // addr_advance = 0; // } // // if (prev_state->file != curr_state.file) // { // debug_line_data.Append8(DW_LNS_set_file); // debug_line_data.Append32_as_ULEB128(curr_state.file); // } // // if (prev_state->column != curr_state.column) // { // debug_line_data.Append8(DW_LNS_set_column); // debug_line_data.Append32_as_ULEB128(curr_state.column); // } // // // Don't do anything fancy if we are at the end of a sequence // // as we don't want to push any extra rows since the // DW_LNE_end_sequence // // will push a row itself! // if (curr_state.end_sequence) // { // if (line_increment != 0) // { // debug_line_data.Append8(DW_LNS_advance_line); // debug_line_data.Append32_as_SLEB128(line_increment); // } // // if (addr_advance > 0) // { // debug_line_data.Append8(DW_LNS_advance_pc); // debug_line_data.Append32_as_ULEB128(addr_advance); // } // // // Now push the end sequence on! // debug_line_data.Append8(0); // debug_line_data.Append8(1); // debug_line_data.Append8(DW_LNE_end_sequence); // // prev_state = &reset_state; // } // else // { // if (line_increment || addr_advance) // { // if (line_increment > max_line_increment_for_special_opcode) // { // debug_line_data.Append8(DW_LNS_advance_line); // debug_line_data.Append32_as_SLEB128(line_increment); // line_increment = 0; // } // // uint32_t special_opcode = (line_increment >= // prologue->line_base) ? ((line_increment - // prologue->line_base) + (prologue->line_range * addr_advance) // + prologue->opcode_base) : 256; // if (special_opcode > 255) // { // // Both the address and line won't fit in one special // opcode // // check to see if just the line advance will? // uint32_t special_opcode_line = ((line_increment >= // prologue->line_base) && (line_increment != 0)) ? // ((line_increment - prologue->line_base) + // prologue->opcode_base) : 256; // // // if (special_opcode_line > 255) // { // // Nope, the line advance won't fit by itself, check // the address increment by itself // uint32_t special_opcode_addr = addr_advance ? // ((0 - prologue->line_base) + // (prologue->line_range * addr_advance) + // prologue->opcode_base) : 256; // // if (special_opcode_addr > 255) // { // // Neither the address nor the line will fit in // a // // special opcode, we must manually enter both // then // // do a DW_LNS_copy to push a row (special // opcode // // automatically imply a new row is pushed) // if (line_increment != 0) // { // debug_line_data.Append8(DW_LNS_advance_line); // debug_line_data.Append32_as_SLEB128(line_increment); // } // // if (addr_advance > 0) // { // debug_line_data.Append8(DW_LNS_advance_pc); // debug_line_data.Append32_as_ULEB128(addr_advance); // } // // // Now push a row onto the line table manually // debug_line_data.Append8(DW_LNS_copy); // // } // else // { // // The address increment alone will fit into a // special opcode // // so modify our line change, then issue a // special opcode // // for the address increment and it will push a // row into the // // line table // if (line_increment != 0) // { // debug_line_data.Append8(DW_LNS_advance_line); // debug_line_data.Append32_as_SLEB128(line_increment); // } // // // Advance of line and address will fit into a // single byte special opcode // // and this will also push a row onto the line // table // debug_line_data.Append8(special_opcode_addr); // } // } // else // { // // The line change alone will fit into a special // opcode // // so modify our address increment first, then issue // a // // special opcode for the line change and it will // push // // a row into the line table // if (addr_advance > 0) // { // debug_line_data.Append8(DW_LNS_advance_pc); // debug_line_data.Append32_as_ULEB128(addr_advance); // } // // // Advance of line and address will fit into a // single byte special opcode // // and this will also push a row onto the line table // debug_line_data.Append8(special_opcode_line); // } // } // else // { // // Advance of line and address will fit into a single // byte special opcode // // and this will also push a row onto the line table // debug_line_data.Append8(special_opcode); // } // } // prev_state = &curr_state; // } // } // } //}