DWARFDebugInfoEntry.cpp
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//===-- DWARFDebugInfoEntry.cpp ---------------------------------*- C++ -*-===//
//
// 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 "DWARFDebugInfoEntry.h"
#include <assert.h>
#include <algorithm>
#include "llvm/Support/LEB128.h"
#include "lldb/Core/Module.h"
#include "lldb/Expression/DWARFExpression.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Utility/Stream.h"
#include "DWARFCompileUnit.h"
#include "DWARFDebugAbbrev.h"
#include "DWARFDebugAranges.h"
#include "DWARFDebugInfo.h"
#include "DWARFDebugRanges.h"
#include "DWARFDeclContext.h"
#include "DWARFFormValue.h"
#include "DWARFUnit.h"
#include "SymbolFileDWARF.h"
#include "SymbolFileDWARFDwo.h"
using namespace lldb_private;
using namespace std;
extern int g_verbose;
// Extract a debug info entry for a given DWARFUnit from the data
// starting at the offset in offset_ptr
bool DWARFDebugInfoEntry::Extract(const DWARFDataExtractor &data,
const DWARFUnit *cu,
lldb::offset_t *offset_ptr) {
m_offset = *offset_ptr;
m_parent_idx = 0;
m_sibling_idx = 0;
const uint64_t abbr_idx = data.GetULEB128(offset_ptr);
lldbassert(abbr_idx <= UINT16_MAX);
m_abbr_idx = abbr_idx;
// assert (fixed_form_sizes); // For best performance this should be
// specified!
if (m_abbr_idx) {
lldb::offset_t offset = *offset_ptr;
const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu);
if (abbrevDecl == nullptr) {
cu->GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError(
"{0x%8.8x}: invalid abbreviation code %u, please file a bug and "
"attach the file at the start of this error message",
m_offset, (unsigned)abbr_idx);
// WE can't parse anymore if the DWARF is borked...
*offset_ptr = UINT32_MAX;
return false;
}
m_tag = abbrevDecl->Tag();
m_has_children = abbrevDecl->HasChildren();
// Skip all data in the .debug_info or .debug_types for the attributes
const uint32_t numAttributes = abbrevDecl->NumAttributes();
uint32_t i;
dw_form_t form;
for (i = 0; i < numAttributes; ++i) {
form = abbrevDecl->GetFormByIndexUnchecked(i);
llvm::Optional<uint8_t> fixed_skip_size =
DWARFFormValue::GetFixedSize(form, cu);
if (fixed_skip_size)
offset += *fixed_skip_size;
else {
bool form_is_indirect = false;
do {
form_is_indirect = false;
uint32_t form_size = 0;
switch (form) {
// Blocks if inlined data that have a length field and the data bytes
// inlined in the .debug_info/.debug_types
case DW_FORM_exprloc:
case DW_FORM_block:
form_size = data.GetULEB128(&offset);
break;
case DW_FORM_block1:
form_size = data.GetU8_unchecked(&offset);
break;
case DW_FORM_block2:
form_size = data.GetU16_unchecked(&offset);
break;
case DW_FORM_block4:
form_size = data.GetU32_unchecked(&offset);
break;
// Inlined NULL terminated C-strings
case DW_FORM_string:
data.GetCStr(&offset);
break;
// Compile unit address sized values
case DW_FORM_addr:
form_size = cu->GetAddressByteSize();
break;
case DW_FORM_ref_addr:
if (cu->GetVersion() <= 2)
form_size = cu->GetAddressByteSize();
else
form_size = 4;
break;
// 0 sized form
case DW_FORM_flag_present:
form_size = 0;
break;
// 1 byte values
case DW_FORM_addrx1:
case DW_FORM_data1:
case DW_FORM_flag:
case DW_FORM_ref1:
case DW_FORM_strx1:
form_size = 1;
break;
// 2 byte values
case DW_FORM_addrx2:
case DW_FORM_data2:
case DW_FORM_ref2:
case DW_FORM_strx2:
form_size = 2;
break;
// 3 byte values
case DW_FORM_addrx3:
case DW_FORM_strx3:
form_size = 3;
break;
// 4 byte values
case DW_FORM_addrx4:
case DW_FORM_data4:
case DW_FORM_ref4:
case DW_FORM_strx4:
form_size = 4;
break;
// 8 byte values
case DW_FORM_data8:
case DW_FORM_ref8:
case DW_FORM_ref_sig8:
form_size = 8;
break;
// signed or unsigned LEB 128 values
case DW_FORM_addrx:
case DW_FORM_loclistx:
case DW_FORM_rnglistx:
case DW_FORM_sdata:
case DW_FORM_udata:
case DW_FORM_ref_udata:
case DW_FORM_GNU_addr_index:
case DW_FORM_GNU_str_index:
case DW_FORM_strx:
data.Skip_LEB128(&offset);
break;
case DW_FORM_indirect:
form_is_indirect = true;
form = data.GetULEB128(&offset);
break;
case DW_FORM_strp:
case DW_FORM_sec_offset:
data.GetU32(&offset);
break;
case DW_FORM_implicit_const:
form_size = 0;
break;
default:
*offset_ptr = m_offset;
return false;
}
offset += form_size;
} while (form_is_indirect);
}
}
*offset_ptr = offset;
return true;
} else {
m_tag = llvm::dwarf::DW_TAG_null;
m_has_children = false;
return true; // NULL debug tag entry
}
return false;
}
static DWARFRangeList GetRangesOrReportError(DWARFUnit &unit,
const DWARFDebugInfoEntry &die,
const DWARFFormValue &value) {
llvm::Expected<DWARFRangeList> expected_ranges =
(value.Form() == DW_FORM_rnglistx)
? unit.FindRnglistFromIndex(value.Unsigned())
: unit.FindRnglistFromOffset(value.Unsigned());
if (expected_ranges)
return std::move(*expected_ranges);
unit.GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError(
"{0x%8.8x}: DIE has DW_AT_ranges(0x%" PRIx64 ") attribute, but "
"range extraction failed (%s), please file a bug "
"and attach the file at the start of this error message",
die.GetOffset(), value.Unsigned(),
toString(expected_ranges.takeError()).c_str());
return DWARFRangeList();
}
// GetDIENamesAndRanges
//
// Gets the valid address ranges for a given DIE by looking for a
// DW_AT_low_pc/DW_AT_high_pc pair, DW_AT_entry_pc, or DW_AT_ranges attributes.
bool DWARFDebugInfoEntry::GetDIENamesAndRanges(
DWARFUnit *cu, const char *&name, const char *&mangled,
DWARFRangeList &ranges, int &decl_file, int &decl_line, int &decl_column,
int &call_file, int &call_line, int &call_column,
DWARFExpression *frame_base) const {
dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
std::vector<DWARFDIE> dies;
bool set_frame_base_loclist_addr = false;
const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu);
SymbolFileDWARF &dwarf = cu->GetSymbolFileDWARF();
lldb::ModuleSP module = dwarf.GetObjectFile()->GetModule();
if (abbrevDecl) {
const DWARFDataExtractor &data = cu->GetData();
lldb::offset_t offset = GetFirstAttributeOffset();
if (!data.ValidOffset(offset))
return false;
const uint32_t numAttributes = abbrevDecl->NumAttributes();
bool do_offset = false;
for (uint32_t i = 0; i < numAttributes; ++i) {
DWARFFormValue form_value(cu);
dw_attr_t attr;
abbrevDecl->GetAttrAndFormValueByIndex(i, attr, form_value);
if (form_value.ExtractValue(data, &offset)) {
switch (attr) {
case DW_AT_low_pc:
lo_pc = form_value.Address();
if (do_offset)
hi_pc += lo_pc;
do_offset = false;
break;
case DW_AT_entry_pc:
lo_pc = form_value.Address();
break;
case DW_AT_high_pc:
if (form_value.Form() == DW_FORM_addr ||
form_value.Form() == DW_FORM_addrx ||
form_value.Form() == DW_FORM_GNU_addr_index) {
hi_pc = form_value.Address();
} else {
hi_pc = form_value.Unsigned();
if (lo_pc == LLDB_INVALID_ADDRESS)
do_offset = hi_pc != LLDB_INVALID_ADDRESS;
else
hi_pc += lo_pc; // DWARF 4 introduces <offset-from-lo-pc> to save
// on relocations
}
break;
case DW_AT_ranges:
ranges = GetRangesOrReportError(*cu, *this, form_value);
break;
case DW_AT_name:
if (name == nullptr)
name = form_value.AsCString();
break;
case DW_AT_MIPS_linkage_name:
case DW_AT_linkage_name:
if (mangled == nullptr)
mangled = form_value.AsCString();
break;
case DW_AT_abstract_origin:
dies.push_back(form_value.Reference());
break;
case DW_AT_specification:
dies.push_back(form_value.Reference());
break;
case DW_AT_decl_file:
if (decl_file == 0)
decl_file = form_value.Unsigned();
break;
case DW_AT_decl_line:
if (decl_line == 0)
decl_line = form_value.Unsigned();
break;
case DW_AT_decl_column:
if (decl_column == 0)
decl_column = form_value.Unsigned();
break;
case DW_AT_call_file:
if (call_file == 0)
call_file = form_value.Unsigned();
break;
case DW_AT_call_line:
if (call_line == 0)
call_line = form_value.Unsigned();
break;
case DW_AT_call_column:
if (call_column == 0)
call_column = form_value.Unsigned();
break;
case DW_AT_frame_base:
if (frame_base) {
if (form_value.BlockData()) {
uint32_t block_offset =
form_value.BlockData() - data.GetDataStart();
uint32_t block_length = form_value.Unsigned();
*frame_base = DWARFExpression(
module, DataExtractor(data, block_offset, block_length), cu);
} else {
DataExtractor data = cu->GetLocationData();
const dw_offset_t offset = form_value.Unsigned();
if (data.ValidOffset(offset)) {
data = DataExtractor(data, offset, data.GetByteSize() - offset);
*frame_base = DWARFExpression(module, data, cu);
if (lo_pc != LLDB_INVALID_ADDRESS) {
assert(lo_pc >= cu->GetBaseAddress());
frame_base->SetLocationListAddresses(cu->GetBaseAddress(),
lo_pc);
} else {
set_frame_base_loclist_addr = true;
}
}
}
}
break;
default:
break;
}
}
}
}
if (ranges.IsEmpty()) {
if (lo_pc != LLDB_INVALID_ADDRESS) {
if (hi_pc != LLDB_INVALID_ADDRESS && hi_pc > lo_pc)
ranges.Append(DWARFRangeList::Entry(lo_pc, hi_pc - lo_pc));
else
ranges.Append(DWARFRangeList::Entry(lo_pc, 0));
}
}
if (set_frame_base_loclist_addr) {
dw_addr_t lowest_range_pc = ranges.GetMinRangeBase(0);
assert(lowest_range_pc >= cu->GetBaseAddress());
frame_base->SetLocationListAddresses(cu->GetBaseAddress(), lowest_range_pc);
}
if (ranges.IsEmpty() || name == nullptr || mangled == nullptr) {
for (const DWARFDIE &die : dies) {
if (die) {
die.GetDIE()->GetDIENamesAndRanges(die.GetCU(), name, mangled, ranges,
decl_file, decl_line, decl_column,
call_file, call_line, call_column);
}
}
}
return !ranges.IsEmpty();
}
// Dump
//
// Dumps a debug information entry and all of it's attributes to the specified
// stream.
void DWARFDebugInfoEntry::Dump(const DWARFUnit *cu, Stream &s,
uint32_t recurse_depth) const {
const DWARFDataExtractor &data = cu->GetData();
lldb::offset_t offset = m_offset;
if (data.ValidOffset(offset)) {
dw_uleb128_t abbrCode = data.GetULEB128(&offset);
s.Printf("\n0x%8.8x: ", m_offset);
s.Indent();
if (abbrCode != m_abbr_idx) {
s.Printf("error: DWARF has been modified\n");
} else if (abbrCode) {
const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu);
if (abbrevDecl) {
s.PutCString(DW_TAG_value_to_name(abbrevDecl->Tag()));
s.Printf(" [%u] %c\n", abbrCode, abbrevDecl->HasChildren() ? '*' : ' ');
// Dump all data in the .debug_info/.debug_types for the attributes
const uint32_t numAttributes = abbrevDecl->NumAttributes();
for (uint32_t i = 0; i < numAttributes; ++i) {
DWARFFormValue form_value(cu);
dw_attr_t attr;
abbrevDecl->GetAttrAndFormValueByIndex(i, attr, form_value);
DumpAttribute(cu, data, &offset, s, attr, form_value);
}
const DWARFDebugInfoEntry *child = GetFirstChild();
if (recurse_depth > 0 && child) {
s.IndentMore();
while (child) {
child->Dump(cu, s, recurse_depth - 1);
child = child->GetSibling();
}
s.IndentLess();
}
} else
s.Printf("Abbreviation code note found in 'debug_abbrev' class for "
"code: %u\n",
abbrCode);
} else {
s.Printf("NULL\n");
}
}
}
// DumpAttribute
//
// Dumps a debug information entry attribute along with it's form. Any special
// display of attributes is done (disassemble location lists, show enumeration
// values for attributes, etc).
void DWARFDebugInfoEntry::DumpAttribute(
const DWARFUnit *cu, const DWARFDataExtractor &data,
lldb::offset_t *offset_ptr, Stream &s, dw_attr_t attr,
DWARFFormValue &form_value) {
bool show_form = s.GetFlags().Test(DWARFDebugInfo::eDumpFlag_ShowForm);
s.Printf(" ");
s.Indent(DW_AT_value_to_name(attr));
if (show_form) {
s.Printf("[%s", DW_FORM_value_to_name(form_value.Form()));
}
if (!form_value.ExtractValue(data, offset_ptr))
return;
if (show_form) {
if (form_value.Form() == DW_FORM_indirect) {
s.Printf(" [%s]", DW_FORM_value_to_name(form_value.Form()));
}
s.PutCString("] ");
}
s.PutCString("( ");
// Check to see if we have any special attribute formatters
switch (attr) {
case DW_AT_stmt_list:
s.Printf("0x%8.8" PRIx64, form_value.Unsigned());
break;
case DW_AT_language:
s.PutCString(DW_LANG_value_to_name(form_value.Unsigned()));
break;
case DW_AT_encoding:
s.PutCString(DW_ATE_value_to_name(form_value.Unsigned()));
break;
case DW_AT_frame_base:
case DW_AT_location:
case DW_AT_data_member_location: {
const uint8_t *blockData = form_value.BlockData();
if (blockData) {
// Location description is inlined in data in the form value
DWARFDataExtractor locationData(data,
(*offset_ptr) - form_value.Unsigned(),
form_value.Unsigned());
DWARFExpression::PrintDWARFExpression(
s, locationData, DWARFUnit::GetAddressByteSize(cu), 4, false);
} else {
// We have a location list offset as the value that is the offset into
// the .debug_loc section that describes the value over it's lifetime
uint64_t debug_loc_offset = form_value.Unsigned();
DWARFExpression::PrintDWARFLocationList(s, cu, cu->GetLocationData(),
debug_loc_offset);
}
} break;
case DW_AT_abstract_origin:
case DW_AT_specification: {
DWARFDIE abstract_die = form_value.Reference();
form_value.Dump(s);
// *ostrm_ptr << HEX32 << abstract_die.GetOffset() << " ( ";
abstract_die.GetName(s);
} break;
case DW_AT_type: {
DWARFDIE type_die = form_value.Reference();
s.PutCString(" ( ");
type_die.AppendTypeName(s);
s.PutCString(" )");
} break;
default:
break;
}
s.PutCString(" )\n");
}
// Get all attribute values for a given DIE, including following any
// specification or abstract origin attributes and including those in the
// results. Any duplicate attributes will have the first instance take
// precedence (this can happen for declaration attributes).
size_t DWARFDebugInfoEntry::GetAttributes(
const DWARFUnit *cu, DWARFAttributes &attributes,
uint32_t curr_depth) const {
const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu);
if (abbrevDecl) {
const DWARFDataExtractor &data = cu->GetData();
lldb::offset_t offset = GetFirstAttributeOffset();
const uint32_t num_attributes = abbrevDecl->NumAttributes();
for (uint32_t i = 0; i < num_attributes; ++i) {
DWARFFormValue form_value(cu);
dw_attr_t attr;
abbrevDecl->GetAttrAndFormValueByIndex(i, attr, form_value);
const dw_form_t form = form_value.Form();
// If we are tracking down DW_AT_specification or DW_AT_abstract_origin
// attributes, the depth will be non-zero. We need to omit certain
// attributes that don't make sense.
switch (attr) {
case DW_AT_sibling:
case DW_AT_declaration:
if (curr_depth > 0) {
// This attribute doesn't make sense when combined with the DIE that
// references this DIE. We know a DIE is referencing this DIE because
// curr_depth is not zero
break;
}
LLVM_FALLTHROUGH;
default:
attributes.Append(cu, offset, attr, form);
break;
}
if ((attr == DW_AT_specification) || (attr == DW_AT_abstract_origin)) {
if (form_value.ExtractValue(data, &offset)) {
DWARFDIE spec_die = form_value.Reference();
if (spec_die)
spec_die.GetAttributes(attributes, curr_depth + 1);
}
} else {
llvm::Optional<uint8_t> fixed_skip_size = DWARFFormValue::GetFixedSize(form, cu);
if (fixed_skip_size)
offset += *fixed_skip_size;
else
DWARFFormValue::SkipValue(form, data, &offset, cu);
}
}
} else {
attributes.Clear();
}
return attributes.Size();
}
// GetAttributeValue
//
// Get the value of an attribute and return the .debug_info or .debug_types
// offset of the attribute if it was properly extracted into form_value,
// or zero if we fail since an offset of zero is invalid for an attribute (it
// would be a compile unit header).
dw_offset_t DWARFDebugInfoEntry::GetAttributeValue(
const DWARFUnit *cu, const dw_attr_t attr, DWARFFormValue &form_value,
dw_offset_t *end_attr_offset_ptr,
bool check_specification_or_abstract_origin) const {
if (const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu)) {
uint32_t attr_idx = abbrevDecl->FindAttributeIndex(attr);
if (attr_idx != DW_INVALID_INDEX) {
const DWARFDataExtractor &data = cu->GetData();
lldb::offset_t offset = GetFirstAttributeOffset();
uint32_t idx = 0;
while (idx < attr_idx)
DWARFFormValue::SkipValue(abbrevDecl->GetFormByIndex(idx++),
data, &offset, cu);
const dw_offset_t attr_offset = offset;
form_value.SetUnit(cu);
form_value.SetForm(abbrevDecl->GetFormByIndex(idx));
if (form_value.ExtractValue(data, &offset)) {
if (end_attr_offset_ptr)
*end_attr_offset_ptr = offset;
return attr_offset;
}
}
}
if (check_specification_or_abstract_origin) {
if (GetAttributeValue(cu, DW_AT_specification, form_value)) {
DWARFDIE die = form_value.Reference();
if (die) {
dw_offset_t die_offset = die.GetDIE()->GetAttributeValue(
die.GetCU(), attr, form_value, end_attr_offset_ptr, false);
if (die_offset)
return die_offset;
}
}
if (GetAttributeValue(cu, DW_AT_abstract_origin, form_value)) {
DWARFDIE die = form_value.Reference();
if (die) {
dw_offset_t die_offset = die.GetDIE()->GetAttributeValue(
die.GetCU(), attr, form_value, end_attr_offset_ptr, false);
if (die_offset)
return die_offset;
}
}
}
return 0;
}
// GetAttributeValueAsString
//
// Get the value of an attribute as a string return it. The resulting pointer
// to the string data exists within the supplied SymbolFileDWARF and will only
// be available as long as the SymbolFileDWARF is still around and it's content
// doesn't change.
const char *DWARFDebugInfoEntry::GetAttributeValueAsString(
const DWARFUnit *cu, const dw_attr_t attr, const char *fail_value,
bool check_specification_or_abstract_origin) const {
DWARFFormValue form_value;
if (GetAttributeValue(cu, attr, form_value, nullptr,
check_specification_or_abstract_origin))
return form_value.AsCString();
return fail_value;
}
// GetAttributeValueAsUnsigned
//
// Get the value of an attribute as unsigned and return it.
uint64_t DWARFDebugInfoEntry::GetAttributeValueAsUnsigned(
const DWARFUnit *cu, const dw_attr_t attr, uint64_t fail_value,
bool check_specification_or_abstract_origin) const {
DWARFFormValue form_value;
if (GetAttributeValue(cu, attr, form_value, nullptr,
check_specification_or_abstract_origin))
return form_value.Unsigned();
return fail_value;
}
// GetAttributeValueAsReference
//
// Get the value of an attribute as reference and fix up and compile unit
// relative offsets as needed.
DWARFDIE DWARFDebugInfoEntry::GetAttributeValueAsReference(
const DWARFUnit *cu, const dw_attr_t attr,
bool check_specification_or_abstract_origin) const {
DWARFFormValue form_value;
if (GetAttributeValue(cu, attr, form_value, nullptr,
check_specification_or_abstract_origin))
return form_value.Reference();
return {};
}
uint64_t DWARFDebugInfoEntry::GetAttributeValueAsAddress(
const DWARFUnit *cu, const dw_attr_t attr, uint64_t fail_value,
bool check_specification_or_abstract_origin) const {
DWARFFormValue form_value;
if (GetAttributeValue(cu, attr, form_value, nullptr,
check_specification_or_abstract_origin))
return form_value.Address();
return fail_value;
}
// GetAttributeHighPC
//
// Get the hi_pc, adding hi_pc to lo_pc when specified as an <offset-from-low-
// pc>.
//
// Returns the hi_pc or fail_value.
dw_addr_t DWARFDebugInfoEntry::GetAttributeHighPC(
const DWARFUnit *cu, dw_addr_t lo_pc, uint64_t fail_value,
bool check_specification_or_abstract_origin) const {
DWARFFormValue form_value;
if (GetAttributeValue(cu, DW_AT_high_pc, form_value, nullptr,
check_specification_or_abstract_origin)) {
dw_form_t form = form_value.Form();
if (form == DW_FORM_addr || form == DW_FORM_addrx ||
form == DW_FORM_GNU_addr_index)
return form_value.Address();
// DWARF4 can specify the hi_pc as an <offset-from-lowpc>
return lo_pc + form_value.Unsigned();
}
return fail_value;
}
// GetAttributeAddressRange
//
// Get the lo_pc and hi_pc, adding hi_pc to lo_pc when specified as an <offset-
// from-low-pc>.
//
// Returns true or sets lo_pc and hi_pc to fail_value.
bool DWARFDebugInfoEntry::GetAttributeAddressRange(
const DWARFUnit *cu, dw_addr_t &lo_pc, dw_addr_t &hi_pc,
uint64_t fail_value, bool check_specification_or_abstract_origin) const {
lo_pc = GetAttributeValueAsAddress(cu, DW_AT_low_pc, fail_value,
check_specification_or_abstract_origin);
if (lo_pc != fail_value) {
hi_pc = GetAttributeHighPC(cu, lo_pc, fail_value,
check_specification_or_abstract_origin);
if (hi_pc != fail_value)
return true;
}
lo_pc = fail_value;
hi_pc = fail_value;
return false;
}
size_t DWARFDebugInfoEntry::GetAttributeAddressRanges(
DWARFUnit *cu, DWARFRangeList &ranges, bool check_hi_lo_pc,
bool check_specification_or_abstract_origin) const {
ranges.Clear();
DWARFFormValue form_value;
if (GetAttributeValue(cu, DW_AT_ranges, form_value)) {
ranges = GetRangesOrReportError(*cu, *this, form_value);
} else if (check_hi_lo_pc) {
dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
if (GetAttributeAddressRange(cu, lo_pc, hi_pc, LLDB_INVALID_ADDRESS,
check_specification_or_abstract_origin)) {
if (lo_pc < hi_pc)
ranges.Append(DWARFRangeList::Entry(lo_pc, hi_pc - lo_pc));
}
}
return ranges.GetSize();
}
// GetName
//
// Get value of the DW_AT_name attribute and return it if one exists, else
// return NULL.
const char *DWARFDebugInfoEntry::GetName(const DWARFUnit *cu) const {
return GetAttributeValueAsString(cu, DW_AT_name, nullptr, true);
}
// GetMangledName
//
// Get value of the DW_AT_MIPS_linkage_name attribute and return it if one
// exists, else return the value of the DW_AT_name attribute
const char *
DWARFDebugInfoEntry::GetMangledName(const DWARFUnit *cu,
bool substitute_name_allowed) const {
const char *name = nullptr;
name = GetAttributeValueAsString(cu, DW_AT_MIPS_linkage_name, nullptr, true);
if (name)
return name;
name = GetAttributeValueAsString(cu, DW_AT_linkage_name, nullptr, true);
if (name)
return name;
if (!substitute_name_allowed)
return nullptr;
name = GetAttributeValueAsString(cu, DW_AT_name, nullptr, true);
return name;
}
// GetPubname
//
// Get value the name for a DIE as it should appear for a .debug_pubnames or
// .debug_pubtypes section.
const char *DWARFDebugInfoEntry::GetPubname(const DWARFUnit *cu) const {
const char *name = nullptr;
if (!cu)
return name;
name = GetAttributeValueAsString(cu, DW_AT_MIPS_linkage_name, nullptr, true);
if (name)
return name;
name = GetAttributeValueAsString(cu, DW_AT_linkage_name, nullptr, true);
if (name)
return name;
name = GetAttributeValueAsString(cu, DW_AT_name, nullptr, true);
return name;
}
// BuildAddressRangeTable
void DWARFDebugInfoEntry::BuildAddressRangeTable(
const DWARFUnit *cu, DWARFDebugAranges *debug_aranges) const {
if (m_tag) {
if (m_tag == DW_TAG_subprogram) {
dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
if (GetAttributeAddressRange(cu, lo_pc, hi_pc, LLDB_INVALID_ADDRESS)) {
/// printf("BuildAddressRangeTable() 0x%8.8x: %30s: [0x%8.8x -
/// 0x%8.8x)\n", m_offset, DW_TAG_value_to_name(tag), lo_pc, hi_pc);
debug_aranges->AppendRange(cu->GetOffset(), lo_pc, hi_pc);
}
}
const DWARFDebugInfoEntry *child = GetFirstChild();
while (child) {
child->BuildAddressRangeTable(cu, debug_aranges);
child = child->GetSibling();
}
}
}
// BuildFunctionAddressRangeTable
//
// This function is very similar to the BuildAddressRangeTable function except
// that the actual DIE offset for the function is placed in the table instead
// of the compile unit offset (which is the way the standard .debug_aranges
// section does it).
void DWARFDebugInfoEntry::BuildFunctionAddressRangeTable(
const DWARFUnit *cu, DWARFDebugAranges *debug_aranges) const {
if (m_tag) {
if (m_tag == DW_TAG_subprogram) {
dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
if (GetAttributeAddressRange(cu, lo_pc, hi_pc, LLDB_INVALID_ADDRESS)) {
// printf("BuildAddressRangeTable() 0x%8.8x: [0x%16.16" PRIx64 " -
// 0x%16.16" PRIx64 ")\n", m_offset, lo_pc, hi_pc); // DEBUG ONLY
debug_aranges->AppendRange(GetOffset(), lo_pc, hi_pc);
}
}
const DWARFDebugInfoEntry *child = GetFirstChild();
while (child) {
child->BuildFunctionAddressRangeTable(cu, debug_aranges);
child = child->GetSibling();
}
}
}
void DWARFDebugInfoEntry::GetDWARFDeclContext(
DWARFUnit *cu, DWARFDeclContext &dwarf_decl_ctx) const {
const dw_tag_t tag = Tag();
if (tag != DW_TAG_compile_unit && tag != DW_TAG_partial_unit) {
dwarf_decl_ctx.AppendDeclContext(tag, GetName(cu));
DWARFDIE parent_decl_ctx_die = GetParentDeclContextDIE(cu);
if (parent_decl_ctx_die && parent_decl_ctx_die.GetDIE() != this) {
if (parent_decl_ctx_die.Tag() != DW_TAG_compile_unit &&
parent_decl_ctx_die.Tag() != DW_TAG_partial_unit)
parent_decl_ctx_die.GetDIE()->GetDWARFDeclContext(
parent_decl_ctx_die.GetCU(), dwarf_decl_ctx);
}
}
}
DWARFDIE
DWARFDebugInfoEntry::GetParentDeclContextDIE(DWARFUnit *cu) const {
DWARFAttributes attributes;
GetAttributes(cu, attributes);
return GetParentDeclContextDIE(cu, attributes);
}
DWARFDIE
DWARFDebugInfoEntry::GetParentDeclContextDIE(
DWARFUnit *cu, const DWARFAttributes &attributes) const {
DWARFDIE die(cu, const_cast<DWARFDebugInfoEntry *>(this));
while (die) {
// If this is the original DIE that we are searching for a declaration for,
// then don't look in the cache as we don't want our own decl context to be
// our decl context...
if (die.GetDIE() != this) {
switch (die.Tag()) {
case DW_TAG_compile_unit:
case DW_TAG_partial_unit:
case DW_TAG_namespace:
case DW_TAG_structure_type:
case DW_TAG_union_type:
case DW_TAG_class_type:
return die;
default:
break;
}
}
DWARFDIE spec_die = attributes.FormValueAsReference(DW_AT_specification);
if (spec_die) {
DWARFDIE decl_ctx_die = spec_die.GetParentDeclContextDIE();
if (decl_ctx_die)
return decl_ctx_die;
}
DWARFDIE abs_die = attributes.FormValueAsReference(DW_AT_abstract_origin);
if (abs_die) {
DWARFDIE decl_ctx_die = abs_die.GetParentDeclContextDIE();
if (decl_ctx_die)
return decl_ctx_die;
}
die = die.GetParent();
}
return DWARFDIE();
}
const char *DWARFDebugInfoEntry::GetQualifiedName(DWARFUnit *cu,
std::string &storage) const {
DWARFAttributes attributes;
GetAttributes(cu, attributes);
return GetQualifiedName(cu, attributes, storage);
}
const char *
DWARFDebugInfoEntry::GetQualifiedName(DWARFUnit *cu,
const DWARFAttributes &attributes,
std::string &storage) const {
const char *name = GetName(cu);
if (name) {
DWARFDIE parent_decl_ctx_die = GetParentDeclContextDIE(cu);
storage.clear();
// TODO: change this to get the correct decl context parent....
while (parent_decl_ctx_die) {
const dw_tag_t parent_tag = parent_decl_ctx_die.Tag();
switch (parent_tag) {
case DW_TAG_namespace: {
const char *namespace_name = parent_decl_ctx_die.GetName();
if (namespace_name) {
storage.insert(0, "::");
storage.insert(0, namespace_name);
} else {
storage.insert(0, "(anonymous namespace)::");
}
parent_decl_ctx_die = parent_decl_ctx_die.GetParentDeclContextDIE();
} break;
case DW_TAG_class_type:
case DW_TAG_structure_type:
case DW_TAG_union_type: {
const char *class_union_struct_name = parent_decl_ctx_die.GetName();
if (class_union_struct_name) {
storage.insert(0, "::");
storage.insert(0, class_union_struct_name);
}
parent_decl_ctx_die = parent_decl_ctx_die.GetParentDeclContextDIE();
} break;
default:
parent_decl_ctx_die.Clear();
break;
}
}
if (storage.empty())
storage.append("::");
storage.append(name);
}
if (storage.empty())
return nullptr;
return storage.c_str();
}
bool DWARFDebugInfoEntry::LookupAddress(const dw_addr_t address, DWARFUnit *cu,
DWARFDebugInfoEntry **function_die,
DWARFDebugInfoEntry **block_die) {
bool found_address = false;
if (m_tag) {
bool check_children = false;
bool match_addr_range = false;
// printf("0x%8.8x: %30s: address = 0x%8.8x - ", m_offset,
// DW_TAG_value_to_name(tag), address);
switch (m_tag) {
case DW_TAG_array_type:
break;
case DW_TAG_class_type:
check_children = true;
break;
case DW_TAG_entry_point:
case DW_TAG_enumeration_type:
case DW_TAG_formal_parameter:
case DW_TAG_imported_declaration:
case DW_TAG_label:
break;
case DW_TAG_lexical_block:
check_children = true;
match_addr_range = true;
break;
case DW_TAG_member:
case DW_TAG_pointer_type:
case DW_TAG_reference_type:
break;
case DW_TAG_compile_unit:
match_addr_range = true;
break;
case DW_TAG_string_type:
break;
case DW_TAG_structure_type:
check_children = true;
break;
case DW_TAG_subroutine_type:
case DW_TAG_typedef:
case DW_TAG_union_type:
case DW_TAG_unspecified_parameters:
case DW_TAG_variant:
break;
case DW_TAG_common_block:
check_children = true;
break;
case DW_TAG_common_inclusion:
case DW_TAG_inheritance:
break;
case DW_TAG_inlined_subroutine:
check_children = true;
match_addr_range = true;
break;
case DW_TAG_module:
match_addr_range = true;
break;
case DW_TAG_ptr_to_member_type:
case DW_TAG_set_type:
case DW_TAG_subrange_type:
case DW_TAG_with_stmt:
case DW_TAG_access_declaration:
case DW_TAG_base_type:
break;
case DW_TAG_catch_block:
match_addr_range = true;
break;
case DW_TAG_const_type:
case DW_TAG_constant:
case DW_TAG_enumerator:
case DW_TAG_file_type:
case DW_TAG_friend:
case DW_TAG_namelist:
case DW_TAG_namelist_item:
case DW_TAG_packed_type:
break;
case DW_TAG_subprogram:
match_addr_range = true;
break;
case DW_TAG_template_type_parameter:
case DW_TAG_template_value_parameter:
case DW_TAG_GNU_template_parameter_pack:
case DW_TAG_thrown_type:
break;
case DW_TAG_try_block:
match_addr_range = true;
break;
case DW_TAG_variant_part:
case DW_TAG_variable:
case DW_TAG_volatile_type:
case DW_TAG_dwarf_procedure:
case DW_TAG_restrict_type:
case DW_TAG_interface_type:
break;
case DW_TAG_namespace:
check_children = true;
break;
case DW_TAG_imported_module:
case DW_TAG_unspecified_type:
break;
case DW_TAG_partial_unit:
match_addr_range = true;
break;
case DW_TAG_imported_unit:
case DW_TAG_shared_type:
default:
break;
}
if (match_addr_range) {
dw_addr_t lo_pc =
GetAttributeValueAsAddress(cu, DW_AT_low_pc, LLDB_INVALID_ADDRESS);
if (lo_pc != LLDB_INVALID_ADDRESS) {
dw_addr_t hi_pc = GetAttributeHighPC(cu, lo_pc, LLDB_INVALID_ADDRESS);
if (hi_pc != LLDB_INVALID_ADDRESS) {
// printf("\n0x%8.8x: %30s: address = 0x%8.8x [0x%8.8x - 0x%8.8x) ",
// m_offset, DW_TAG_value_to_name(tag), address, lo_pc, hi_pc);
if ((lo_pc <= address) && (address < hi_pc)) {
found_address = true;
// puts("***MATCH***");
switch (m_tag) {
case DW_TAG_compile_unit: // File
case DW_TAG_partial_unit: // File
check_children =
((function_die != nullptr) || (block_die != nullptr));
break;
case DW_TAG_subprogram: // Function
if (function_die)
*function_die = this;
check_children = (block_die != nullptr);
break;
case DW_TAG_inlined_subroutine: // Inlined Function
case DW_TAG_lexical_block: // Block { } in code
if (block_die) {
*block_die = this;
check_children = true;
}
break;
default:
check_children = true;
break;
}
}
} else {
// Compile units may not have a valid high/low pc when there
// are address gaps in subroutines so we must always search
// if there is no valid high and low PC.
check_children =
(m_tag == DW_TAG_compile_unit || m_tag == DW_TAG_partial_unit) &&
((function_die != nullptr) || (block_die != nullptr));
}
} else {
DWARFRangeList ranges;
if (GetAttributeAddressRanges(cu, ranges, /*check_hi_lo_pc*/ false) &&
ranges.FindEntryThatContains(address)) {
found_address = true;
// puts("***MATCH***");
switch (m_tag) {
case DW_TAG_compile_unit: // File
case DW_TAG_partial_unit: // File
check_children =
((function_die != nullptr) || (block_die != nullptr));
break;
case DW_TAG_subprogram: // Function
if (function_die)
*function_die = this;
check_children = (block_die != nullptr);
break;
case DW_TAG_inlined_subroutine: // Inlined Function
case DW_TAG_lexical_block: // Block { } in code
if (block_die) {
*block_die = this;
check_children = true;
}
break;
default:
check_children = true;
break;
}
} else {
check_children = false;
}
}
}
if (check_children) {
// printf("checking children\n");
DWARFDebugInfoEntry *child = GetFirstChild();
while (child) {
if (child->LookupAddress(address, cu, function_die, block_die))
return true;
child = child->GetSibling();
}
}
}
return found_address;
}
lldb::offset_t DWARFDebugInfoEntry::GetFirstAttributeOffset() const {
return GetOffset() + llvm::getULEB128Size(m_abbr_idx);
}
const DWARFAbbreviationDeclaration *
DWARFDebugInfoEntry::GetAbbreviationDeclarationPtr(const DWARFUnit *cu) const {
if (cu) {
const DWARFAbbreviationDeclarationSet *abbrev_set = cu->GetAbbreviations();
if (abbrev_set)
return abbrev_set->GetAbbreviationDeclaration(m_abbr_idx);
}
return nullptr;
}
bool DWARFDebugInfoEntry::operator==(const DWARFDebugInfoEntry &rhs) const {
return m_offset == rhs.m_offset && m_parent_idx == rhs.m_parent_idx &&
m_sibling_idx == rhs.m_sibling_idx &&
m_abbr_idx == rhs.m_abbr_idx && m_has_children == rhs.m_has_children &&
m_tag == rhs.m_tag;
}
bool DWARFDebugInfoEntry::operator!=(const DWARFDebugInfoEntry &rhs) const {
return !(*this == rhs);
}