ladybird/Userland/Libraries/LibDebug/Dwarf/AbbreviationsMap.cpp

75 lines
2.6 KiB
C++

/*
* Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "AbbreviationsMap.h"
#include "DwarfInfo.h"
#include <AK/LEB128.h>
#include <AK/MemoryStream.h>
namespace Debug::Dwarf {
AbbreviationsMap::AbbreviationsMap(DwarfInfo const& dwarf_info, u32 offset)
: m_dwarf_info(dwarf_info)
, m_offset(offset)
{
populate_map().release_value_but_fixme_should_propagate_errors();
}
ErrorOr<void> AbbreviationsMap::populate_map()
{
FixedMemoryStream abbreviation_stream { m_dwarf_info.abbreviation_data() };
TRY(abbreviation_stream.discard(m_offset));
while (!abbreviation_stream.is_eof()) {
size_t abbreviation_code = TRY(abbreviation_stream.read_value<LEB128<size_t>>());
// An abbreviation code of 0 marks the end of the
// abbreviations for a given compilation unit
if (abbreviation_code == 0)
break;
size_t tag = TRY(abbreviation_stream.read_value<LEB128<size_t>>());
auto has_children = TRY(abbreviation_stream.read_value<u8>());
AbbreviationEntry abbreviation_entry {};
abbreviation_entry.tag = static_cast<EntryTag>(tag);
abbreviation_entry.has_children = (has_children == 1);
AttributeSpecification current_attribute_specification {};
do {
size_t attribute_value = TRY(abbreviation_stream.read_value<LEB128<size_t>>());
size_t form_value = TRY(abbreviation_stream.read_value<LEB128<size_t>>());
current_attribute_specification.attribute = static_cast<Attribute>(attribute_value);
current_attribute_specification.form = static_cast<AttributeDataForm>(form_value);
if (current_attribute_specification.form == AttributeDataForm::ImplicitConst) {
ssize_t data_value = TRY(abbreviation_stream.read_value<LEB128<ssize_t>>());
current_attribute_specification.value = data_value;
}
if (current_attribute_specification.attribute != Attribute::None) {
abbreviation_entry.attribute_specifications.append(current_attribute_specification);
}
} while (current_attribute_specification.attribute != Attribute::None || current_attribute_specification.form != AttributeDataForm::None);
m_entries.set(static_cast<u32>(abbreviation_code), move(abbreviation_entry));
}
return {};
}
AbbreviationsMap::AbbreviationEntry const* AbbreviationsMap::get(u32 code) const
{
auto it = m_entries.find(code);
if (it == m_entries.end()) {
return nullptr;
}
return &it->value;
}
}