//----------------------------------------------------------------------
// Parse
//
// Parses the .debug_info section and uses the .debug_abbrev section
// and various other sections in the SymbolFileDWARF class and calls the
// supplied callback function each time a compile unit header, or debug
// information entry is successfully parsed. This function can be used
// for different tasks such as parsing the file contents into a
// structured data, dumping, verifying and much more.
//----------------------------------------------------------------------
void DWARFDebugInfo::Parse(SymbolFileDWARF *dwarf2Data, Callback callback,
void *userData) {
if (dwarf2Data) {
lldb::offset_t offset = 0;
uint32_t depth = 0;
DWARFDebugInfoEntry die;
DWARFCompileUnitSP cu;
while ((cu = DWARFCompileUnit::Extract(dwarf2Data, &offset))) {
const dw_offset_t next_cu_offset = cu->GetNextCompileUnitOffset();
depth = 0;
// Call the callback function with no DIE pointer for the compile unit
// and get the offset that we are to continue to parse from
offset = callback(dwarf2Data, cu.get(), NULL, offset, depth, userData);
// Make sure we are within our compile unit
if (offset < next_cu_offset) {
// We are in our compile unit, parse starting at the offset
// we were told to parse
bool done = false;
while (!done && die.Extract(dwarf2Data, cu.get(), &offset)) {
// Call the callback function with DIE pointer that falls within the
// compile unit
offset =
callback(dwarf2Data, cu.get(), &die, offset, depth, userData);
if (die.IsNULL()) {
if (depth)
--depth;
else
done = true; // We are done with this compile unit!
} else if (die.HasChildren())
++depth;
}
}
// Make sure the offset returned is valid, and if not stop parsing.
// Returning DW_INVALID_OFFSET from this callback is a good way to end
// all parsing
if (!dwarf2Data->get_debug_info_data().ValidOffset(offset))
break;
// Make sure we start on a proper
offset = next_cu_offset;
}
}
}
//----------------------------------------------------------------------
// ParseCompileUnitDIEsIfNeeded
//
// Parses a compile unit and indexes its DIEs if it hasn't already been
// done.
//----------------------------------------------------------------------
size_t
DWARFCompileUnit::ExtractDIEsIfNeeded (bool cu_die_only)
{
const size_t initial_die_array_size = m_die_array.size();
if ((cu_die_only && initial_die_array_size > 0) || initial_die_array_size > 1)
return 0; // Already parsed
Timer scoped_timer (__PRETTY_FUNCTION__,
"%8.8x: DWARFCompileUnit::ExtractDIEsIfNeeded( cu_die_only = %i )",
m_offset,
cu_die_only);
// Set the offset to that of the first DIE and calculate the start of the
// next compilation unit header.
lldb::offset_t offset = GetFirstDIEOffset();
lldb::offset_t next_cu_offset = GetNextCompileUnitOffset();
DWARFDebugInfoEntry die;
// Keep a flat array of the DIE for binary lookup by DIE offset
if (!cu_die_only)
{
Log *log (LogChannelDWARF::GetLogIfAny(DWARF_LOG_DEBUG_INFO | DWARF_LOG_LOOKUPS));
if (log)
{
m_dwarf2Data->GetObjectFile()->GetModule()->LogMessageVerboseBacktrace (log,
"DWARFCompileUnit::ExtractDIEsIfNeeded () for compile unit at .debug_info[0x%8.8x]",
GetOffset());
}
}
uint32_t depth = 0;
// We are in our compile unit, parse starting at the offset
// we were told to parse
const DWARFDataExtractor& debug_info_data = m_dwarf2Data->get_debug_info_data();
std::vector<uint32_t> die_index_stack;
die_index_stack.reserve(32);
die_index_stack.push_back(0);
bool prev_die_had_children = false;
DWARFFormValue::FixedFormSizes fixed_form_sizes =
DWARFFormValue::GetFixedFormSizesForAddressSize (GetAddressByteSize(), m_is_dwarf64);
while (offset < next_cu_offset &&
die.FastExtract (debug_info_data, this, fixed_form_sizes, &offset))
{
// if (log)
// log->Printf("0x%8.8x: %*.*s%s%s",
// die.GetOffset(),
// depth * 2, depth * 2, "",
// DW_TAG_value_to_name (die.Tag()),
// die.HasChildren() ? " *" : "");
const bool null_die = die.IsNULL();
if (depth == 0)
{
uint64_t base_addr = die.GetAttributeValueAsUnsigned(m_dwarf2Data, this, DW_AT_low_pc, LLDB_INVALID_ADDRESS);
if (base_addr == LLDB_INVALID_ADDRESS)
base_addr = die.GetAttributeValueAsUnsigned(m_dwarf2Data, this, DW_AT_entry_pc, 0);
SetBaseAddress (base_addr);
if (initial_die_array_size == 0)
AddDIE (die);
if (cu_die_only)
return 1;
}
else
{
if (null_die)
{
if (prev_die_had_children)
{
// This will only happen if a DIE says is has children
// but all it contains is a NULL tag. Since we are removing
// the NULL DIEs from the list (saves up to 25% in C++ code),
// we need a way to let the DIE know that it actually doesn't
// have children.
if (!m_die_array.empty())
m_die_array.back().SetEmptyChildren(true);
}
}
else
{
die.SetParentIndex(m_die_array.size() - die_index_stack[depth-1]);
if (die_index_stack.back())
m_die_array[die_index_stack.back()].SetSiblingIndex(m_die_array.size()-die_index_stack.back());
// Only push the DIE if it isn't a NULL DIE
m_die_array.push_back(die);
}
}
if (null_die)
{
// NULL DIE.
if (!die_index_stack.empty())
die_index_stack.pop_back();
if (depth > 0)
--depth;
if (depth == 0)
break; // We are done with this compile unit!
prev_die_had_children = false;
}
else
{
die_index_stack.back() = m_die_array.size() - 1;
// Normal DIE
const bool die_has_children = die.HasChildren();
if (die_has_children)
{
die_index_stack.push_back(0);
++depth;
}
prev_die_had_children = die_has_children;
}
}
// Give a little bit of info if we encounter corrupt DWARF (our offset
// should always terminate at or before the start of the next compilation
// unit header).
if (offset > next_cu_offset)
{
m_dwarf2Data->GetObjectFile()->GetModule()->ReportWarning ("DWARF compile unit extends beyond its bounds cu 0x%8.8x at 0x%8.8" PRIx64 "\n",
GetOffset(),
offset);
}
// Since std::vector objects will double their size, we really need to
// make a new array with the perfect size so we don't end up wasting
// space. So here we copy and swap to make sure we don't have any extra
// memory taken up.
if (m_die_array.size () < m_die_array.capacity())
{
DWARFDebugInfoEntry::collection exact_size_die_array (m_die_array.begin(), m_die_array.end());
exact_size_die_array.swap (m_die_array);
}
Log *verbose_log (LogChannelDWARF::GetLogIfAll (DWARF_LOG_DEBUG_INFO | DWARF_LOG_VERBOSE));
if (verbose_log)
{
StreamString strm;
Dump(&strm);
if (m_die_array.empty())
strm.Printf("error: no DIE for compile unit");
else
m_die_array[0].Dump(m_dwarf2Data, this, strm, UINT32_MAX);
verbose_log->PutCString (strm.GetString().c_str());
}
return m_die_array.size();
}
//----------------------------------------------------------------------
// Parse
//
// Parses the .debug_info section and uses the .debug_abbrev section
// and various other sections in the SymbolFileDWARF class and calls the
// supplied callback function each time a compile unit header, or debug
// information entry is successfully parsed. This function can be used
// for different tasks such as parsing the file contents into a
// structured data, dumping, verifying and much more.
//----------------------------------------------------------------------
void
DWARFDebugInfo::Parse(SymbolFileDWARF* dwarf2Data, Callback callback, void* userData)
{
if (dwarf2Data)
{
lldb::offset_t offset = 0;
uint32_t depth = 0;
DWARFCompileUnitSP cu(new DWARFCompileUnit(dwarf2Data));
if (cu.get() == NULL)
return;
DWARFDebugInfoEntry die;
while (cu->Extract(dwarf2Data->get_debug_info_data(), &offset))
{
const dw_offset_t next_cu_offset = cu->GetNextCompileUnitOffset();
depth = 0;
// Call the callback function with no DIE pointer for the compile unit
// and get the offset that we are to continue to parse from
offset = callback(dwarf2Data, cu.get(), NULL, offset, depth, userData);
// Make sure we are within our compile unit
if (offset < next_cu_offset)
{
// We are in our compile unit, parse starting at the offset
// we were told to parse
bool done = false;
while (!done && die.Extract(dwarf2Data, cu.get(), &offset))
{
// Call the callback function with DIE pointer that falls within the compile unit
offset = callback(dwarf2Data, cu.get(), &die, offset, depth, userData);
if (die.IsNULL())
{
if (depth)
--depth;
else
done = true; // We are done with this compile unit!
}
else if (die.HasChildren())
++depth;
}
}
// Make sure the offset returned is valid, and if not stop parsing.
// Returning DW_INVALID_OFFSET from this callback is a good way to end
// all parsing
if (!dwarf2Data->get_debug_info_data().ValidOffset(offset))
break;
// See if during the callback anyone retained a copy of the compile
// unit other than ourselves and if so, let whomever did own the object
// and create a new one for our own use!
if (!cu.unique())
cu.reset(new DWARFCompileUnit(dwarf2Data));
// Make sure we start on a proper
offset = next_cu_offset;
}
}
}
// Parses a compile unit and indexes its DIEs, m_die_array_mutex must be
// held R/W and m_die_array must be empty.
void DWARFUnit::ExtractDIEsRWLocked() {
llvm::sys::ScopedWriter first_die_lock(m_first_die_mutex);
static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
Timer scoped_timer(
func_cat, "%8.8x: DWARFUnit::ExtractDIEsIfNeeded()", m_offset);
// Set the offset to that of the first DIE and calculate the start of the
// next compilation unit header.
lldb::offset_t offset = GetFirstDIEOffset();
lldb::offset_t next_cu_offset = GetNextCompileUnitOffset();
DWARFDebugInfoEntry die;
uint32_t depth = 0;
// We are in our compile unit, parse starting at the offset we were told to
// parse
const DWARFDataExtractor &data = GetData();
std::vector<uint32_t> die_index_stack;
die_index_stack.reserve(32);
die_index_stack.push_back(0);
bool prev_die_had_children = false;
DWARFFormValue::FixedFormSizes fixed_form_sizes =
DWARFFormValue::GetFixedFormSizesForAddressSize(GetAddressByteSize());
while (offset < next_cu_offset &&
die.FastExtract(data, this, fixed_form_sizes, &offset)) {
const bool null_die = die.IsNULL();
if (depth == 0) {
assert(m_die_array.empty() && "Compile unit DIE already added");
// The average bytes per DIE entry has been seen to be around 14-20 so
// lets pre-reserve half of that since we are now stripping the NULL
// tags.
// Only reserve the memory if we are adding children of the main
// compile unit DIE. The compile unit DIE is always the first entry, so
// if our size is 1, then we are adding the first compile unit child
// DIE and should reserve the memory.
m_die_array.reserve(GetDebugInfoSize() / 24);
m_die_array.push_back(die);
if (!m_first_die)
AddUnitDIE(m_die_array.front());
} else {
if (null_die) {
if (prev_die_had_children) {
// This will only happen if a DIE says is has children but all it
// contains is a NULL tag. Since we are removing the NULL DIEs from
// the list (saves up to 25% in C++ code), we need a way to let the
// DIE know that it actually doesn't have children.
if (!m_die_array.empty())
m_die_array.back().SetHasChildren(false);
}
} else {
die.SetParentIndex(m_die_array.size() - die_index_stack[depth - 1]);
if (die_index_stack.back())
m_die_array[die_index_stack.back()].SetSiblingIndex(
m_die_array.size() - die_index_stack.back());
// Only push the DIE if it isn't a NULL DIE
m_die_array.push_back(die);
}
}
if (null_die) {
// NULL DIE.
if (!die_index_stack.empty())
die_index_stack.pop_back();
if (depth > 0)
--depth;
prev_die_had_children = false;
} else {
die_index_stack.back() = m_die_array.size() - 1;
// Normal DIE
const bool die_has_children = die.HasChildren();
if (die_has_children) {
die_index_stack.push_back(0);
++depth;
}
prev_die_had_children = die_has_children;
}
if (depth == 0)
break; // We are done with this compile unit!
}
if (!m_die_array.empty()) {
if (m_first_die) {
// Only needed for the assertion.
m_first_die.SetHasChildren(m_die_array.front().HasChildren());
lldbassert(m_first_die == m_die_array.front());
}
m_first_die = m_die_array.front();
}
m_die_array.shrink_to_fit();
if (m_dwo_symbol_file) {
DWARFUnit *dwo_cu = m_dwo_symbol_file->GetCompileUnit();
dwo_cu->ExtractDIEsIfNeeded();
}
}