llvm-project/lldb/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp

116 lines
4.6 KiB
C++

//===-- DWARFCompileUnit.cpp ----------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "DWARFCompileUnit.h"
#include "DWARFDebugAranges.h"
#include "SymbolFileDWARFDebugMap.h"
#include "lldb/Symbol/CompileUnit.h"
#include "lldb/Symbol/LineTable.h"
#include "lldb/Utility/Stream.h"
using namespace lldb;
using namespace lldb_private;
void DWARFCompileUnit::Dump(Stream *s) const {
s->Printf("0x%8.8x: Compile Unit: length = 0x%8.8x, version = 0x%4.4x, "
"abbr_offset = 0x%8.8x, addr_size = 0x%2.2x (next CU at "
"{0x%8.8x})\n",
GetOffset(), GetLength(), GetVersion(), GetAbbrevOffset(),
GetAddressByteSize(), GetNextUnitOffset());
}
void DWARFCompileUnit::BuildAddressRangeTable(
DWARFDebugAranges *debug_aranges) {
// This function is usually called if there in no .debug_aranges section in
// order to produce a compile unit level set of address ranges that is
// accurate.
size_t num_debug_aranges = debug_aranges->GetNumRanges();
// First get the compile unit DIE only and check if it has a DW_AT_ranges
const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
const dw_offset_t cu_offset = GetOffset();
if (die) {
DWARFRangeList ranges;
const size_t num_ranges =
die->GetAttributeAddressRanges(this, ranges, false);
if (num_ranges > 0) {
// This compile unit has DW_AT_ranges, assume this is correct if it is
// present since clang no longer makes .debug_aranges by default and it
// emits DW_AT_ranges for DW_TAG_compile_units. GCC also does this with
// recent GCC builds.
for (size_t i = 0; i < num_ranges; ++i) {
const DWARFRangeList::Entry &range = ranges.GetEntryRef(i);
debug_aranges->AppendRange(cu_offset, range.GetRangeBase(),
range.GetRangeEnd());
}
return; // We got all of our ranges from the DW_AT_ranges attribute
}
}
// We don't have a DW_AT_ranges attribute, so we need to parse the DWARF
// If the DIEs weren't parsed, then we don't want all dies for all compile
// units to stay loaded when they weren't needed. So we can end up parsing
// the DWARF and then throwing them all away to keep memory usage down.
ScopedExtractDIEs clear_dies(ExtractDIEsScoped());
die = DIEPtr();
if (die)
die->BuildAddressRangeTable(this, debug_aranges);
if (debug_aranges->GetNumRanges() == num_debug_aranges) {
// We got nothing from the functions, maybe we have a line tables only
// situation. Check the line tables and build the arange table from this.
SymbolContext sc;
sc.comp_unit = m_dwarf.GetCompUnitForDWARFCompUnit(*this);
if (sc.comp_unit) {
SymbolFileDWARFDebugMap *debug_map_sym_file =
m_dwarf.GetDebugMapSymfile();
if (debug_map_sym_file == nullptr) {
if (LineTable *line_table = sc.comp_unit->GetLineTable()) {
LineTable::FileAddressRanges file_ranges;
const bool append = true;
const size_t num_ranges =
line_table->GetContiguousFileAddressRanges(file_ranges, append);
for (uint32_t idx = 0; idx < num_ranges; ++idx) {
const LineTable::FileAddressRanges::Entry &range =
file_ranges.GetEntryRef(idx);
debug_aranges->AppendRange(cu_offset, range.GetRangeBase(),
range.GetRangeEnd());
}
}
} else
debug_map_sym_file->AddOSOARanges(&m_dwarf, debug_aranges);
}
}
if (debug_aranges->GetNumRanges() == num_debug_aranges) {
// We got nothing from the functions, maybe we have a line tables only
// situation. Check the line tables and build the arange table from this.
SymbolContext sc;
sc.comp_unit = m_dwarf.GetCompUnitForDWARFCompUnit(*this);
if (sc.comp_unit) {
if (LineTable *line_table = sc.comp_unit->GetLineTable()) {
LineTable::FileAddressRanges file_ranges;
const bool append = true;
const size_t num_ranges =
line_table->GetContiguousFileAddressRanges(file_ranges, append);
for (uint32_t idx = 0; idx < num_ranges; ++idx) {
const LineTable::FileAddressRanges::Entry &range =
file_ranges.GetEntryRef(idx);
debug_aranges->AppendRange(GetOffset(), range.GetRangeBase(),
range.GetRangeEnd());
}
}
}
}
}