Google Git Google Git
Sign in
llvm/llvm-project/edde212818e3bd1c19ade3cf52927bb7cdfd520f/./lldb/source/Symbol/CompactUnwindInfo.cpp
blob: cdbbeb554c6885ec0cf5772e54584a956373b42c [file]
//===-- CompactUnwindInfo.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 "lldb/Symbol/CompactUnwindInfo.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/Section.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Symbol/UnwindPlan.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/Target.h"
#include "lldb/Utility/ArchSpec.h"
#include "lldb/Utility/DataBufferHeap.h"
#include "lldb/Utility/LLDBLog.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/StreamString.h"
#include "llvm/Support/MathExtras.h"
#include <algorithm>
#include <memory>
using namespace lldb;
using namespace lldb_private;
namespace lldb_private {
// Constants from <mach-o/compact_unwind_encoding.h>
FLAGS_ANONYMOUS_ENUM(){
UNWIND_IS_NOT_FUNCTION_START = 0x80000000, UNWIND_HAS_LSDA = 0x40000000,
UNWIND_PERSONALITY_MASK = 0x30000000,
};
FLAGS_ANONYMOUS_ENUM(){
UNWIND_X86_MODE_MASK = 0x0F000000,
UNWIND_X86_MODE_EBP_FRAME = 0x01000000,
UNWIND_X86_MODE_STACK_IMMD = 0x02000000,
UNWIND_X86_MODE_STACK_IND = 0x03000000,
UNWIND_X86_MODE_DWARF = 0x04000000,
UNWIND_X86_EBP_FRAME_REGISTERS = 0x00007FFF,
UNWIND_X86_EBP_FRAME_OFFSET = 0x00FF0000,
UNWIND_X86_FRAMELESS_STACK_SIZE = 0x00FF0000,
UNWIND_X86_FRAMELESS_STACK_ADJUST = 0x0000E000,
UNWIND_X86_FRAMELESS_STACK_REG_COUNT = 0x00001C00,
UNWIND_X86_FRAMELESS_STACK_REG_PERMUTATION = 0x000003FF,
UNWIND_X86_DWARF_SECTION_OFFSET = 0x00FFFFFF,
};
enum {
UNWIND_X86_REG_NONE = 0,
UNWIND_X86_REG_EBX = 1,
UNWIND_X86_REG_ECX = 2,
UNWIND_X86_REG_EDX = 3,
UNWIND_X86_REG_EDI = 4,
UNWIND_X86_REG_ESI = 5,
UNWIND_X86_REG_EBP = 6,
};
FLAGS_ANONYMOUS_ENUM(){
UNWIND_X86_64_MODE_MASK = 0x0F000000,
UNWIND_X86_64_MODE_RBP_FRAME = 0x01000000,
UNWIND_X86_64_MODE_STACK_IMMD = 0x02000000,
UNWIND_X86_64_MODE_STACK_IND = 0x03000000,
UNWIND_X86_64_MODE_DWARF = 0x04000000,
UNWIND_X86_64_RBP_FRAME_REGISTERS = 0x00007FFF,
UNWIND_X86_64_RBP_FRAME_OFFSET = 0x00FF0000,
UNWIND_X86_64_FRAMELESS_STACK_SIZE = 0x00FF0000,
UNWIND_X86_64_FRAMELESS_STACK_ADJUST = 0x0000E000,
UNWIND_X86_64_FRAMELESS_STACK_REG_COUNT = 0x00001C00,
UNWIND_X86_64_FRAMELESS_STACK_REG_PERMUTATION = 0x000003FF,
UNWIND_X86_64_DWARF_SECTION_OFFSET = 0x00FFFFFF,
};
enum {
UNWIND_X86_64_REG_NONE = 0,
UNWIND_X86_64_REG_RBX = 1,
UNWIND_X86_64_REG_R12 = 2,
UNWIND_X86_64_REG_R13 = 3,
UNWIND_X86_64_REG_R14 = 4,
UNWIND_X86_64_REG_R15 = 5,
UNWIND_X86_64_REG_RBP = 6,
};
FLAGS_ANONYMOUS_ENUM(){
UNWIND_ARM64_MODE_MASK = 0x0F000000,
UNWIND_ARM64_MODE_FRAMELESS = 0x02000000,
UNWIND_ARM64_MODE_DWARF = 0x03000000,
UNWIND_ARM64_MODE_FRAME = 0x04000000,
UNWIND_ARM64_FRAME_X19_X20_PAIR = 0x00000001,
UNWIND_ARM64_FRAME_X21_X22_PAIR = 0x00000002,
UNWIND_ARM64_FRAME_X23_X24_PAIR = 0x00000004,
UNWIND_ARM64_FRAME_X25_X26_PAIR = 0x00000008,
UNWIND_ARM64_FRAME_X27_X28_PAIR = 0x00000010,
UNWIND_ARM64_FRAME_D8_D9_PAIR = 0x00000100,
UNWIND_ARM64_FRAME_D10_D11_PAIR = 0x00000200,
UNWIND_ARM64_FRAME_D12_D13_PAIR = 0x00000400,
UNWIND_ARM64_FRAME_D14_D15_PAIR = 0x00000800,
UNWIND_ARM64_FRAMELESS_STACK_SIZE_MASK = 0x00FFF000,
UNWIND_ARM64_DWARF_SECTION_OFFSET = 0x00FFFFFF,
};
FLAGS_ANONYMOUS_ENUM(){
UNWIND_ARM_MODE_MASK = 0x0F000000,
UNWIND_ARM_MODE_FRAME = 0x01000000,
UNWIND_ARM_MODE_FRAME_D = 0x02000000,
UNWIND_ARM_MODE_DWARF = 0x04000000,
UNWIND_ARM_FRAME_STACK_ADJUST_MASK = 0x00C00000,
UNWIND_ARM_FRAME_FIRST_PUSH_R4 = 0x00000001,
UNWIND_ARM_FRAME_FIRST_PUSH_R5 = 0x00000002,
UNWIND_ARM_FRAME_FIRST_PUSH_R6 = 0x00000004,
UNWIND_ARM_FRAME_SECOND_PUSH_R8 = 0x00000008,
UNWIND_ARM_FRAME_SECOND_PUSH_R9 = 0x00000010,
UNWIND_ARM_FRAME_SECOND_PUSH_R10 = 0x00000020,
UNWIND_ARM_FRAME_SECOND_PUSH_R11 = 0x00000040,
UNWIND_ARM_FRAME_SECOND_PUSH_R12 = 0x00000080,
UNWIND_ARM_FRAME_D_REG_COUNT_MASK = 0x00000700,
UNWIND_ARM_DWARF_SECTION_OFFSET = 0x00FFFFFF,
};
}
#ifndef UNWIND_SECOND_LEVEL_REGULAR
#define UNWIND_SECOND_LEVEL_REGULAR 2
#endif
#ifndef UNWIND_SECOND_LEVEL_COMPRESSED
#define UNWIND_SECOND_LEVEL_COMPRESSED 3
#endif
#ifndef UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET
#define UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(entry) (entry & 0x00FFFFFF)
#endif
#ifndef UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX
#define UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX(entry) \
((entry >> 24) & 0xFF)
#endif
#define EXTRACT_BITS(value, mask) \
((value >> llvm::countr_zero(static_cast<uint32_t>(mask))) & \
(((1 << llvm::popcount(static_cast<uint32_t>(mask)))) - 1))
// constructor
CompactUnwindInfo::CompactUnwindInfo(ObjectFile &objfile, SectionSP &section_sp)
: m_objfile(objfile), m_section_sp(section_sp),
m_section_contents_if_encrypted(), m_mutex(), m_indexes(),
m_indexes_computed(eLazyBoolCalculate), m_unwindinfo_data(),
m_unwindinfo_data_computed(false), m_unwind_header() {}
// destructor
CompactUnwindInfo::~CompactUnwindInfo() = default;
bool CompactUnwindInfo::GetUnwindPlan(Target &target, Address addr,
UnwindPlan &unwind_plan) {
if (!IsValid(target.GetProcessSP())) {
return false;
}
FunctionInfo function_info;
if (GetCompactUnwindInfoForFunction(target, addr, function_info)) {
// shortcut return for functions that have no compact unwind
if (function_info.encoding == 0)
return false;
if (ArchSpec arch = m_objfile.GetArchitecture()) {
Log *log = GetLog(LLDBLog::Unwind);
if (log && log->GetVerbose()) {
StreamString strm;
addr.Dump(
&strm, nullptr,
Address::DumpStyle::DumpStyleResolvedDescriptionNoFunctionArguments,
Address::DumpStyle::DumpStyleFileAddress,
arch.GetAddressByteSize());
LLDB_LOGF(log, "Got compact unwind encoding 0x%x for function %s",
function_info.encoding, strm.GetData());
}
if (function_info.valid_range_offset_start != 0 &&
function_info.valid_range_offset_end != 0) {
SectionList *sl = m_objfile.GetSectionList();
if (sl) {
addr_t func_range_start_file_addr =
function_info.valid_range_offset_start +
m_objfile.GetBaseAddress().GetFileAddress();
AddressRange func_range(func_range_start_file_addr,
function_info.valid_range_offset_end -
function_info.valid_range_offset_start,
sl);
unwind_plan.SetPlanValidAddressRanges({func_range});
}
}
if (arch.GetTriple().getArch() == llvm::Triple::x86_64) {
return CreateUnwindPlan_x86_64(target, function_info, unwind_plan,
addr);
}
if (arch.GetTriple().getArch() == llvm::Triple::aarch64 ||
arch.GetTriple().getArch() == llvm::Triple::aarch64_32) {
return CreateUnwindPlan_arm64(target, function_info, unwind_plan, addr);
}
if (arch.GetTriple().getArch() == llvm::Triple::x86) {
return CreateUnwindPlan_i386(target, function_info, unwind_plan, addr);
}
if (arch.GetTriple().getArch() == llvm::Triple::arm ||
arch.GetTriple().getArch() == llvm::Triple::thumb) {
return CreateUnwindPlan_armv7(target, function_info, unwind_plan, addr);
}
}
}
return false;
}
bool CompactUnwindInfo::IsValid(const ProcessSP &process_sp) {
if (m_section_sp.get() == nullptr)
return false;
if (m_indexes_computed == eLazyBoolYes && m_unwindinfo_data_computed)
return true;
ScanIndex(process_sp);
return m_indexes_computed == eLazyBoolYes && m_unwindinfo_data_computed;
}
void CompactUnwindInfo::ScanIndex(const ProcessSP &process_sp) {
std::lock_guard<std::mutex> guard(m_mutex);
if (m_indexes_computed == eLazyBoolYes && m_unwindinfo_data_computed)
return;
// We can't read the index for some reason.
if (m_indexes_computed == eLazyBoolNo) {
return;
}
Log *log = GetLog(LLDBLog::Unwind);
if (log)
m_objfile.GetModule()->LogMessage(
log, "Reading compact unwind first-level indexes");
if (!m_unwindinfo_data_computed) {
if (m_section_sp->IsEncrypted()) {
// Can't get section contents of a protected/encrypted section until we
// have a live process and can read them out of memory.
if (process_sp.get() == nullptr)
return;
m_section_contents_if_encrypted =
std::make_shared<DataBufferHeap>(m_section_sp->GetByteSize(), 0);
Status error;
if (process_sp->ReadMemory(
m_section_sp->GetLoadBaseAddress(&process_sp->GetTarget()),
m_section_contents_if_encrypted->GetBytes(),
m_section_sp->GetByteSize(),
error) == m_section_sp->GetByteSize() &&
error.Success()) {
m_unwindinfo_data.SetAddressByteSize(
process_sp->GetTarget().GetArchitecture().GetAddressByteSize());
m_unwindinfo_data.SetByteOrder(
process_sp->GetTarget().GetArchitecture().GetByteOrder());
m_unwindinfo_data.SetData(m_section_contents_if_encrypted, 0);
}
} else {
m_objfile.ReadSectionData(m_section_sp.get(), m_unwindinfo_data);
}
if (m_unwindinfo_data.GetByteSize() != m_section_sp->GetByteSize())
return;
m_unwindinfo_data_computed = true;
}
if (m_unwindinfo_data.GetByteSize() > 0) {
offset_t offset = 0;
// struct unwind_info_section_header
// {
// uint32_t version; // UNWIND_SECTION_VERSION
// uint32_t commonEncodingsArraySectionOffset;
// uint32_t commonEncodingsArrayCount;
// uint32_t personalityArraySectionOffset;
// uint32_t personalityArrayCount;
// uint32_t indexSectionOffset;
// uint32_t indexCount;
m_unwind_header.version = m_unwindinfo_data.GetU32(&offset);
m_unwind_header.common_encodings_array_offset =
m_unwindinfo_data.GetU32(&offset);
m_unwind_header.common_encodings_array_count =
m_unwindinfo_data.GetU32(&offset);
m_unwind_header.personality_array_offset =
m_unwindinfo_data.GetU32(&offset);
m_unwind_header.personality_array_count = m_unwindinfo_data.GetU32(&offset);
uint32_t indexSectionOffset = m_unwindinfo_data.GetU32(&offset);
uint32_t indexCount = m_unwindinfo_data.GetU32(&offset);
if (m_unwind_header.common_encodings_array_offset >
m_unwindinfo_data.GetByteSize() ||
m_unwind_header.personality_array_offset >
m_unwindinfo_data.GetByteSize() ||
indexSectionOffset > m_unwindinfo_data.GetByteSize() ||
offset > m_unwindinfo_data.GetByteSize()) {
Debugger::ReportError(
"Invalid offset encountered in compact unwind info, skipping");
// don't trust anything from this compact_unwind section if it looks
// blatantly invalid data in the header.
m_indexes_computed = eLazyBoolNo;
return;
}
// Parse the basic information from the indexes We wait to scan the second
// level page info until it's needed
// struct unwind_info_section_header_index_entry {
// uint32_t functionOffset;
// uint32_t secondLevelPagesSectionOffset;
// uint32_t lsdaIndexArraySectionOffset;
// };
bool clear_address_zeroth_bit = false;
if (ArchSpec arch = m_objfile.GetArchitecture()) {
if (arch.GetTriple().getArch() == llvm::Triple::arm ||
arch.GetTriple().getArch() == llvm::Triple::thumb)
clear_address_zeroth_bit = true;
}
offset = indexSectionOffset;
for (uint32_t idx = 0; idx < indexCount; idx++) {
uint32_t function_offset =
m_unwindinfo_data.GetU32(&offset); // functionOffset
uint32_t second_level_offset =
m_unwindinfo_data.GetU32(&offset); // secondLevelPagesSectionOffset
uint32_t lsda_offset =
m_unwindinfo_data.GetU32(&offset); // lsdaIndexArraySectionOffset
if (second_level_offset > m_section_sp->GetByteSize() ||
lsda_offset > m_section_sp->GetByteSize()) {
m_indexes_computed = eLazyBoolNo;
}
if (clear_address_zeroth_bit)
function_offset &= ~1ull;
UnwindIndex this_index;
this_index.function_offset = function_offset;
this_index.second_level = second_level_offset;
this_index.lsda_array_start = lsda_offset;
if (m_indexes.size() > 0) {
m_indexes[m_indexes.size() - 1].lsda_array_end = lsda_offset;
}
if (second_level_offset == 0) {
this_index.sentinal_entry = true;
}
m_indexes.push_back(this_index);
}
m_indexes_computed = eLazyBoolYes;
} else {
m_indexes_computed = eLazyBoolNo;
}
}
uint32_t CompactUnwindInfo::GetLSDAForFunctionOffset(uint32_t lsda_offset,
uint32_t lsda_count,
uint32_t function_offset) {
// struct unwind_info_section_header_lsda_index_entry {
// uint32_t functionOffset;
// uint32_t lsdaOffset;
// };
offset_t first_entry = lsda_offset;
uint32_t low = 0;
uint32_t high = lsda_count;
while (low < high) {
uint32_t mid = (low + high) / 2;
offset_t offset = first_entry + (mid * 8);
uint32_t mid_func_offset =
m_unwindinfo_data.GetU32(&offset); // functionOffset
uint32_t mid_lsda_offset = m_unwindinfo_data.GetU32(&offset); // lsdaOffset
if (mid_func_offset == function_offset) {
return mid_lsda_offset;
}
if (mid_func_offset < function_offset) {
low = mid + 1;
} else {
high = mid;
}
}
return 0;
}
lldb::offset_t CompactUnwindInfo::BinarySearchRegularSecondPage(
uint32_t entry_page_offset, uint32_t entry_count, uint32_t function_offset,
uint32_t *entry_func_start_offset, uint32_t *entry_func_end_offset) {
// typedef uint32_t compact_unwind_encoding_t;
// struct unwind_info_regular_second_level_entry {
// uint32_t functionOffset;
// compact_unwind_encoding_t encoding;
offset_t first_entry = entry_page_offset;
uint32_t low = 0;
uint32_t high = entry_count;
uint32_t last = high - 1;
while (low < high) {
uint32_t mid = (low + high) / 2;
offset_t offset = first_entry + (mid * 8);
uint32_t mid_func_offset =
m_unwindinfo_data.GetU32(&offset); // functionOffset
uint32_t next_func_offset = 0;
if (mid < last) {
offset = first_entry + ((mid + 1) * 8);
next_func_offset = m_unwindinfo_data.GetU32(&offset); // functionOffset
}
if (mid_func_offset <= function_offset) {
if (mid == last || (next_func_offset > function_offset)) {
if (entry_func_start_offset)
*entry_func_start_offset = mid_func_offset;
if (mid != last && entry_func_end_offset)
*entry_func_end_offset = next_func_offset;
return first_entry + (mid * 8);
} else {
low = mid + 1;
}
} else {
high = mid;
}
}
return LLDB_INVALID_OFFSET;
}
uint32_t CompactUnwindInfo::BinarySearchCompressedSecondPage(
uint32_t entry_page_offset, uint32_t entry_count,
uint32_t function_offset_to_find, uint32_t function_offset_base,
uint32_t *entry_func_start_offset, uint32_t *entry_func_end_offset) {
offset_t first_entry = entry_page_offset;
uint32_t low = 0;
uint32_t high = entry_count;
uint32_t last = high - 1;
while (low < high) {
uint32_t mid = (low + high) / 2;
offset_t offset = first_entry + (mid * 4);
uint32_t entry = m_unwindinfo_data.GetU32(&offset); // entry
uint32_t mid_func_offset = UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(entry);
mid_func_offset += function_offset_base;
uint32_t next_func_offset = 0;
if (mid < last) {
offset = first_entry + ((mid + 1) * 4);
uint32_t next_entry = m_unwindinfo_data.GetU32(&offset); // entry
next_func_offset = UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(next_entry);
next_func_offset += function_offset_base;
}
if (mid_func_offset <= function_offset_to_find) {
if (mid == last || (next_func_offset > function_offset_to_find)) {
if (entry_func_start_offset)
*entry_func_start_offset = mid_func_offset;
if (mid != last && entry_func_end_offset)
*entry_func_end_offset = next_func_offset;
return UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX(entry);
} else {
low = mid + 1;
}
} else {
high = mid;
}
}
return UINT32_MAX;
}
bool CompactUnwindInfo::GetCompactUnwindInfoForFunction(
Target &target, Address address, FunctionInfo &unwind_info) {
unwind_info.encoding = 0;
unwind_info.lsda_address.Clear();
unwind_info.personality_ptr_address.Clear();
if (!IsValid(target.GetProcessSP()))
return false;
addr_t text_section_file_address = LLDB_INVALID_ADDRESS;
SectionList *sl = m_objfile.GetSectionList();
if (sl) {
SectionSP text_sect = sl->FindSectionByType(eSectionTypeCode, true);
if (text_sect.get()) {
text_section_file_address = text_sect->GetFileAddress();
}
}
if (text_section_file_address == LLDB_INVALID_ADDRESS)
return false;
addr_t function_offset =
address.GetFileAddress() - m_objfile.GetBaseAddress().GetFileAddress();
UnwindIndex key;
key.function_offset = function_offset;
std::vector<UnwindIndex>::const_iterator it;
it = llvm::lower_bound(m_indexes, key);
if (it == m_indexes.end()) {
return false;
}
if (it->function_offset != key.function_offset) {
if (it != m_indexes.begin())
--it;
}
if (it->sentinal_entry) {
return false;
}
auto next_it = it + 1;
if (next_it != m_indexes.end()) {
// initialize the function offset end range to be the start of the next
// index offset. If we find an entry which is at the end of the index
// table, this will establish the range end.
unwind_info.valid_range_offset_end = next_it->function_offset;
}
offset_t second_page_offset = it->second_level;
offset_t lsda_array_start = it->lsda_array_start;
offset_t lsda_array_count = (it->lsda_array_end - it->lsda_array_start) / 8;
offset_t offset = second_page_offset;
uint32_t kind = m_unwindinfo_data.GetU32(
&offset); // UNWIND_SECOND_LEVEL_REGULAR or UNWIND_SECOND_LEVEL_COMPRESSED
if (kind == UNWIND_SECOND_LEVEL_REGULAR) {
// struct unwind_info_regular_second_level_page_header {
// uint32_t kind; // UNWIND_SECOND_LEVEL_REGULAR
// uint16_t entryPageOffset;
// uint16_t entryCount;
// typedef uint32_t compact_unwind_encoding_t;
// struct unwind_info_regular_second_level_entry {
// uint32_t functionOffset;
// compact_unwind_encoding_t encoding;
uint16_t entry_page_offset =
m_unwindinfo_data.GetU16(&offset); // entryPageOffset
uint16_t entry_count = m_unwindinfo_data.GetU16(&offset); // entryCount
offset_t entry_offset = BinarySearchRegularSecondPage(
second_page_offset + entry_page_offset, entry_count, function_offset,
&unwind_info.valid_range_offset_start,
&unwind_info.valid_range_offset_end);
if (entry_offset == LLDB_INVALID_OFFSET) {
return false;
}
entry_offset += 4; // skip over functionOffset
unwind_info.encoding = m_unwindinfo_data.GetU32(&entry_offset); // encoding
if (unwind_info.encoding & UNWIND_HAS_LSDA) {
SectionList *sl = m_objfile.GetSectionList();
if (sl) {
uint32_t lsda_offset = GetLSDAForFunctionOffset(
lsda_array_start, lsda_array_count, function_offset);
addr_t objfile_base_address =
m_objfile.GetBaseAddress().GetFileAddress();
unwind_info.lsda_address.ResolveAddressUsingFileSections(
objfile_base_address + lsda_offset, sl);
}
}
if (unwind_info.encoding & UNWIND_PERSONALITY_MASK) {
uint32_t personality_index =
EXTRACT_BITS(unwind_info.encoding, UNWIND_PERSONALITY_MASK);
if (personality_index > 0) {
personality_index--;
if (personality_index < m_unwind_header.personality_array_count) {
offset_t offset = m_unwind_header.personality_array_offset;
offset += 4 * personality_index;
SectionList *sl = m_objfile.GetSectionList();
if (sl) {
uint32_t personality_offset = m_unwindinfo_data.GetU32(&offset);
addr_t objfile_base_address =
m_objfile.GetBaseAddress().GetFileAddress();
unwind_info.personality_ptr_address.ResolveAddressUsingFileSections(
objfile_base_address + personality_offset, sl);
}
}
}
}
return true;
} else if (kind == UNWIND_SECOND_LEVEL_COMPRESSED) {
// struct unwind_info_compressed_second_level_page_header {
// uint32_t kind; // UNWIND_SECOND_LEVEL_COMPRESSED
// uint16_t entryPageOffset; // offset from this 2nd lvl page
// idx to array of entries
// // (an entry has a function
// offset and index into the
// encodings)
// // NB function offset from the
// entry in the compressed page
// // must be added to the index's
// functionOffset value.
// uint16_t entryCount;
// uint16_t encodingsPageOffset; // offset from this 2nd lvl page
// idx to array of encodings
// uint16_t encodingsCount;
uint16_t entry_page_offset =
m_unwindinfo_data.GetU16(&offset); // entryPageOffset
uint16_t entry_count = m_unwindinfo_data.GetU16(&offset); // entryCount
uint16_t encodings_page_offset =
m_unwindinfo_data.GetU16(&offset); // encodingsPageOffset
uint16_t encodings_count =
m_unwindinfo_data.GetU16(&offset); // encodingsCount
uint32_t encoding_index = BinarySearchCompressedSecondPage(
second_page_offset + entry_page_offset, entry_count, function_offset,
it->function_offset, &unwind_info.valid_range_offset_start,
&unwind_info.valid_range_offset_end);
if (encoding_index == UINT32_MAX ||
encoding_index >=
encodings_count + m_unwind_header.common_encodings_array_count) {
return false;
}
uint32_t encoding = 0;
if (encoding_index < m_unwind_header.common_encodings_array_count) {
offset = m_unwind_header.common_encodings_array_offset +
(encoding_index * sizeof(uint32_t));
encoding = m_unwindinfo_data.GetU32(
&offset); // encoding entry from the commonEncodingsArray
} else {
uint32_t page_specific_entry_index =
encoding_index - m_unwind_header.common_encodings_array_count;
offset = second_page_offset + encodings_page_offset +
(page_specific_entry_index * sizeof(uint32_t));
encoding = m_unwindinfo_data.GetU32(
&offset); // encoding entry from the page-specific encoding array
}
if (encoding == 0)
return false;
unwind_info.encoding = encoding;
if (unwind_info.encoding & UNWIND_HAS_LSDA) {
SectionList *sl = m_objfile.GetSectionList();
if (sl) {
uint32_t lsda_offset = GetLSDAForFunctionOffset(
lsda_array_start, lsda_array_count, function_offset);
addr_t objfile_base_address =
m_objfile.GetBaseAddress().GetFileAddress();
unwind_info.lsda_address.ResolveAddressUsingFileSections(
objfile_base_address + lsda_offset, sl);
}
}
if (unwind_info.encoding & UNWIND_PERSONALITY_MASK) {
uint32_t personality_index =
EXTRACT_BITS(unwind_info.encoding, UNWIND_PERSONALITY_MASK);
if (personality_index > 0) {
personality_index--;
if (personality_index < m_unwind_header.personality_array_count) {
offset_t offset = m_unwind_header.personality_array_offset;
offset += 4 * personality_index;
SectionList *sl = m_objfile.GetSectionList();
if (sl) {
uint32_t personality_offset = m_unwindinfo_data.GetU32(&offset);
addr_t objfile_base_address =
m_objfile.GetBaseAddress().GetFileAddress();
unwind_info.personality_ptr_address.ResolveAddressUsingFileSections(
objfile_base_address + personality_offset, sl);
}
}
}
}
return true;
}
return false;
}
enum x86_64_eh_regnum {
rax = 0,
rdx = 1,
rcx = 2,
rbx = 3,
rsi = 4,
rdi = 5,
rbp = 6,
rsp = 7,
r8 = 8,
r9 = 9,
r10 = 10,
r11 = 11,
r12 = 12,
r13 = 13,
r14 = 14,
r15 = 15,
rip = 16 // this is officially the Return Address register number, but close
// enough
};
// Convert the compact_unwind_info.h register numbering scheme to
// eRegisterKindEHFrame (eh_frame) register numbering scheme.
uint32_t translate_to_eh_frame_regnum_x86_64(uint32_t unwind_regno) {
switch (unwind_regno) {
case UNWIND_X86_64_REG_RBX:
return x86_64_eh_regnum::rbx;
case UNWIND_X86_64_REG_R12:
return x86_64_eh_regnum::r12;
case UNWIND_X86_64_REG_R13:
return x86_64_eh_regnum::r13;
case UNWIND_X86_64_REG_R14:
return x86_64_eh_regnum::r14;
case UNWIND_X86_64_REG_R15:
return x86_64_eh_regnum::r15;
case UNWIND_X86_64_REG_RBP:
return x86_64_eh_regnum::rbp;
default:
return LLDB_INVALID_REGNUM;
}
}
bool CompactUnwindInfo::CreateUnwindPlan_x86_64(Target &target,
FunctionInfo &function_info,
UnwindPlan &unwind_plan,
Address pc_or_function_start) {
unwind_plan.SetSourceName("compact unwind info");
unwind_plan.SetSourcedFromCompiler(eLazyBoolYes);
unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
unwind_plan.SetRegisterKind(eRegisterKindEHFrame);
UnwindPlan::Row row;
const int wordsize = 8;
int mode = function_info.encoding & UNWIND_X86_64_MODE_MASK;
switch (mode) {
case UNWIND_X86_64_MODE_RBP_FRAME: {
row.GetCFAValue().SetIsRegisterPlusOffset(
translate_to_eh_frame_regnum_x86_64(UNWIND_X86_64_REG_RBP),
2 * wordsize);
row.SetRegisterLocationToAtCFAPlusOffset(x86_64_eh_regnum::rbp,
wordsize * -2, true);
row.SetRegisterLocationToAtCFAPlusOffset(x86_64_eh_regnum::rip,
wordsize * -1, true);
row.SetRegisterLocationToIsCFAPlusOffset(x86_64_eh_regnum::rsp, 0, true);
uint32_t saved_registers_offset =
EXTRACT_BITS(function_info.encoding, UNWIND_X86_64_RBP_FRAME_OFFSET);
uint32_t saved_registers_locations =
EXTRACT_BITS(function_info.encoding, UNWIND_X86_64_RBP_FRAME_REGISTERS);
saved_registers_offset += 2;
for (int i = 0; i < 5; i++) {
uint32_t regnum = saved_registers_locations & 0x7;
switch (regnum) {
case UNWIND_X86_64_REG_NONE:
break;
case UNWIND_X86_64_REG_RBX:
case UNWIND_X86_64_REG_R12:
case UNWIND_X86_64_REG_R13:
case UNWIND_X86_64_REG_R14:
case UNWIND_X86_64_REG_R15:
row.SetRegisterLocationToAtCFAPlusOffset(
translate_to_eh_frame_regnum_x86_64(regnum),
wordsize * -saved_registers_offset, true);
break;
}
saved_registers_offset--;
saved_registers_locations >>= 3;
}
unwind_plan.AppendRow(std::move(row));
return true;
} break;
case UNWIND_X86_64_MODE_STACK_IND: {
// The clang in Xcode 6 is emitting incorrect compact unwind encodings for
// this style of unwind. It was fixed in llvm r217020. The clang in Xcode
// 7 has this fixed.
return false;
} break;
case UNWIND_X86_64_MODE_STACK_IMMD: {
uint32_t stack_size = EXTRACT_BITS(function_info.encoding,
UNWIND_X86_64_FRAMELESS_STACK_SIZE);
uint32_t register_count = EXTRACT_BITS(
function_info.encoding, UNWIND_X86_64_FRAMELESS_STACK_REG_COUNT);
uint32_t permutation = EXTRACT_BITS(
function_info.encoding, UNWIND_X86_64_FRAMELESS_STACK_REG_PERMUTATION);
if (mode == UNWIND_X86_64_MODE_STACK_IND &&
function_info.valid_range_offset_start != 0) {
uint32_t stack_adjust = EXTRACT_BITS(
function_info.encoding, UNWIND_X86_64_FRAMELESS_STACK_ADJUST);
// offset into the function instructions; 0 == beginning of first
// instruction
uint32_t offset_to_subl_insn = EXTRACT_BITS(
function_info.encoding, UNWIND_X86_64_FRAMELESS_STACK_SIZE);
SectionList *sl = m_objfile.GetSectionList();
if (sl) {
ProcessSP process_sp = target.GetProcessSP();
if (process_sp) {
Address subl_payload_addr(function_info.valid_range_offset_start, sl);
subl_payload_addr.Slide(offset_to_subl_insn);
Status error;
uint64_t large_stack_size = process_sp->ReadUnsignedIntegerFromMemory(
subl_payload_addr.GetLoadAddress(&target), 4, 0, error);
if (large_stack_size != 0 && error.Success()) {
// Got the large stack frame size correctly - use it
stack_size = large_stack_size + (stack_adjust * wordsize);
} else {
return false;
}
} else {
return false;
}
} else {
return false;
}
}
int32_t offset = mode == UNWIND_X86_64_MODE_STACK_IND
? stack_size
: stack_size * wordsize;
row.GetCFAValue().SetIsRegisterPlusOffset(x86_64_eh_regnum::rsp, offset);
row.SetRegisterLocationToAtCFAPlusOffset(x86_64_eh_regnum::rip,
wordsize * -1, true);
row.SetRegisterLocationToIsCFAPlusOffset(x86_64_eh_regnum::rsp, 0, true);
if (register_count > 0) {
// We need to include (up to) 6 registers in 10 bits. That would be 18
// bits if we just used 3 bits per reg to indicate the order they're
// saved on the stack.
//
// This is done with Lehmer code permutation, e.g. see
// http://stackoverflow.com/questions/1506078/fast-permutation-number-
// permutation-mapping-algorithms
int permunreg[6] = {0, 0, 0, 0, 0, 0};
// This decodes the variable-base number in the 10 bits and gives us the
// Lehmer code sequence which can then be decoded.
switch (register_count) {
case 6:
permunreg[0] = permutation / 120; // 120 == 5!
permutation -= (permunreg[0] * 120);
permunreg[1] = permutation / 24; // 24 == 4!
permutation -= (permunreg[1] * 24);
permunreg[2] = permutation / 6; // 6 == 3!
permutation -= (permunreg[2] * 6);
permunreg[3] = permutation / 2; // 2 == 2!
permutation -= (permunreg[3] * 2);
permunreg[4] = permutation; // 1 == 1!
permunreg[5] = 0;
break;
case 5:
permunreg[0] = permutation / 120;
permutation -= (permunreg[0] * 120);
permunreg[1] = permutation / 24;
permutation -= (permunreg[1] * 24);
permunreg[2] = permutation / 6;
permutation -= (permunreg[2] * 6);
permunreg[3] = permutation / 2;
permutation -= (permunreg[3] * 2);
permunreg[4] = permutation;
break;
case 4:
permunreg[0] = permutation / 60;
permutation -= (permunreg[0] * 60);
permunreg[1] = permutation / 12;
permutation -= (permunreg[1] * 12);
permunreg[2] = permutation / 3;
permutation -= (permunreg[2] * 3);
permunreg[3] = permutation;
break;
case 3:
permunreg[0] = permutation / 20;
permutation -= (permunreg[0] * 20);
permunreg[1] = permutation / 4;
permutation -= (permunreg[1] * 4);
permunreg[2] = permutation;
break;
case 2:
permunreg[0] = permutation / 5;
permutation -= (permunreg[0] * 5);
permunreg[1] = permutation;
break;
case 1:
permunreg[0] = permutation;
break;
}
// Decode the Lehmer code for this permutation of the registers v.
// http://en.wikipedia.org/wiki/Lehmer_code
int registers[6] = {UNWIND_X86_64_REG_NONE, UNWIND_X86_64_REG_NONE,
UNWIND_X86_64_REG_NONE, UNWIND_X86_64_REG_NONE,
UNWIND_X86_64_REG_NONE, UNWIND_X86_64_REG_NONE};
bool used[7] = {false, false, false, false, false, false, false};
for (uint32_t i = 0; i < register_count; i++) {
int renum = 0;
for (int j = 1; j < 7; j++) {
if (!used[j]) {
if (renum == permunreg[i]) {
registers[i] = j;
used[j] = true;
break;
}
renum++;
}
}
}
uint32_t saved_registers_offset = 1;
saved_registers_offset++;
for (int i = (sizeof(registers) / sizeof(int)) - 1; i >= 0; i--) {
switch (registers[i]) {
case UNWIND_X86_64_REG_NONE:
break;
case UNWIND_X86_64_REG_RBX:
case UNWIND_X86_64_REG_R12:
case UNWIND_X86_64_REG_R13:
case UNWIND_X86_64_REG_R14:
case UNWIND_X86_64_REG_R15:
case UNWIND_X86_64_REG_RBP:
row.SetRegisterLocationToAtCFAPlusOffset(
translate_to_eh_frame_regnum_x86_64(registers[i]),
wordsize * -saved_registers_offset, true);
saved_registers_offset++;
break;
}
}
}
unwind_plan.AppendRow(std::move(row));
return true;
} break;
case UNWIND_X86_64_MODE_DWARF: {
return false;
} break;
case 0: {
return false;
} break;
}
return false;
}
enum i386_eh_regnum {
eax = 0,
ecx = 1,
edx = 2,
ebx = 3,
ebp = 4,
esp = 5,
esi = 6,
edi = 7,
eip = 8 // this is officially the Return Address register number, but close
// enough
};
// Convert the compact_unwind_info.h register numbering scheme to
// eRegisterKindEHFrame (eh_frame) register numbering scheme.
uint32_t translate_to_eh_frame_regnum_i386(uint32_t unwind_regno) {
switch (unwind_regno) {
case UNWIND_X86_REG_EBX:
return i386_eh_regnum::ebx;
case UNWIND_X86_REG_ECX:
return i386_eh_regnum::ecx;
case UNWIND_X86_REG_EDX:
return i386_eh_regnum::edx;
case UNWIND_X86_REG_EDI:
return i386_eh_regnum::edi;
case UNWIND_X86_REG_ESI:
return i386_eh_regnum::esi;
case UNWIND_X86_REG_EBP:
return i386_eh_regnum::ebp;
default:
return LLDB_INVALID_REGNUM;
}
}
bool CompactUnwindInfo::CreateUnwindPlan_i386(Target &target,
FunctionInfo &function_info,
UnwindPlan &unwind_plan,
Address pc_or_function_start) {
unwind_plan.SetSourceName("compact unwind info");
unwind_plan.SetSourcedFromCompiler(eLazyBoolYes);
unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
unwind_plan.SetRegisterKind(eRegisterKindEHFrame);
UnwindPlan::Row row;
const int wordsize = 4;
int mode = function_info.encoding & UNWIND_X86_MODE_MASK;
switch (mode) {
case UNWIND_X86_MODE_EBP_FRAME: {
row.GetCFAValue().SetIsRegisterPlusOffset(
translate_to_eh_frame_regnum_i386(UNWIND_X86_REG_EBP), 2 * wordsize);
row.SetRegisterLocationToAtCFAPlusOffset(i386_eh_regnum::ebp, wordsize * -2,
true);
row.SetRegisterLocationToAtCFAPlusOffset(i386_eh_regnum::eip, wordsize * -1,
true);
row.SetRegisterLocationToIsCFAPlusOffset(i386_eh_regnum::esp, 0, true);
uint32_t saved_registers_offset =
EXTRACT_BITS(function_info.encoding, UNWIND_X86_EBP_FRAME_OFFSET);
uint32_t saved_registers_locations =
EXTRACT_BITS(function_info.encoding, UNWIND_X86_EBP_FRAME_REGISTERS);
saved_registers_offset += 2;
for (int i = 0; i < 5; i++) {
uint32_t regnum = saved_registers_locations & 0x7;
switch (regnum) {
case UNWIND_X86_REG_NONE:
break;
case UNWIND_X86_REG_EBX:
case UNWIND_X86_REG_ECX:
case UNWIND_X86_REG_EDX:
case UNWIND_X86_REG_EDI:
case UNWIND_X86_REG_ESI:
row.SetRegisterLocationToAtCFAPlusOffset(
translate_to_eh_frame_regnum_i386(regnum),
wordsize * -saved_registers_offset, true);
break;
}
saved_registers_offset--;
saved_registers_locations >>= 3;
}
unwind_plan.AppendRow(std::move(row));
return true;
} break;
case UNWIND_X86_MODE_STACK_IND:
case UNWIND_X86_MODE_STACK_IMMD: {
uint32_t stack_size =
EXTRACT_BITS(function_info.encoding, UNWIND_X86_FRAMELESS_STACK_SIZE);
uint32_t register_count = EXTRACT_BITS(
function_info.encoding, UNWIND_X86_FRAMELESS_STACK_REG_COUNT);
uint32_t permutation = EXTRACT_BITS(
function_info.encoding, UNWIND_X86_FRAMELESS_STACK_REG_PERMUTATION);
if (mode == UNWIND_X86_MODE_STACK_IND &&
function_info.valid_range_offset_start != 0) {
uint32_t stack_adjust = EXTRACT_BITS(function_info.encoding,
UNWIND_X86_FRAMELESS_STACK_ADJUST);
// offset into the function instructions; 0 == beginning of first
// instruction
uint32_t offset_to_subl_insn =
EXTRACT_BITS(function_info.encoding, UNWIND_X86_FRAMELESS_STACK_SIZE);
SectionList *sl = m_objfile.GetSectionList();
if (sl) {
ProcessSP process_sp = target.GetProcessSP();
if (process_sp) {
Address subl_payload_addr(function_info.valid_range_offset_start, sl);
subl_payload_addr.Slide(offset_to_subl_insn);
Status error;
uint64_t large_stack_size = process_sp->ReadUnsignedIntegerFromMemory(
subl_payload_addr.GetLoadAddress(&target), 4, 0, error);
if (large_stack_size != 0 && error.Success()) {
// Got the large stack frame size correctly - use it
stack_size = large_stack_size + (stack_adjust * wordsize);
} else {
return false;
}
} else {
return false;
}
} else {
return false;
}
}
int32_t offset =
mode == UNWIND_X86_MODE_STACK_IND ? stack_size : stack_size * wordsize;
row.GetCFAValue().SetIsRegisterPlusOffset(i386_eh_regnum::esp, offset);
row.SetRegisterLocationToAtCFAPlusOffset(i386_eh_regnum::eip, wordsize * -1,
true);
row.SetRegisterLocationToIsCFAPlusOffset(i386_eh_regnum::esp, 0, true);
if (register_count > 0) {
// We need to include (up to) 6 registers in 10 bits. That would be 18
// bits if we just used 3 bits per reg to indicate the order they're
// saved on the stack.
//
// This is done with Lehmer code permutation, e.g. see
// http://stackoverflow.com/questions/1506078/fast-permutation-number-
// permutation-mapping-algorithms
int permunreg[6] = {0, 0, 0, 0, 0, 0};
// This decodes the variable-base number in the 10 bits and gives us the
// Lehmer code sequence which can then be decoded.
switch (register_count) {
case 6:
permunreg[0] = permutation / 120; // 120 == 5!
permutation -= (permunreg[0] * 120);
permunreg[1] = permutation / 24; // 24 == 4!
permutation -= (permunreg[1] * 24);
permunreg[2] = permutation / 6; // 6 == 3!
permutation -= (permunreg[2] * 6);
permunreg[3] = permutation / 2; // 2 == 2!
permutation -= (permunreg[3] * 2);
permunreg[4] = permutation; // 1 == 1!
permunreg[5] = 0;
break;
case 5:
permunreg[0] = permutation / 120;
permutation -= (permunreg[0] * 120);
permunreg[1] = permutation / 24;
permutation -= (permunreg[1] * 24);
permunreg[2] = permutation / 6;
permutation -= (permunreg[2] * 6);
permunreg[3] = permutation / 2;
permutation -= (permunreg[3] * 2);
permunreg[4] = permutation;
break;
case 4:
permunreg[0] = permutation / 60;
permutation -= (permunreg[0] * 60);
permunreg[1] = permutation / 12;
permutation -= (permunreg[1] * 12);
permunreg[2] = permutation / 3;
permutation -= (permunreg[2] * 3);
permunreg[3] = permutation;
break;
case 3:
permunreg[0] = permutation / 20;
permutation -= (permunreg[0] * 20);
permunreg[1] = permutation / 4;
permutation -= (permunreg[1] * 4);
permunreg[2] = permutation;
break;
case 2:
permunreg[0] = permutation / 5;
permutation -= (permunreg[0] * 5);
permunreg[1] = permutation;
break;
case 1:
permunreg[0] = permutation;
break;
}
// Decode the Lehmer code for this permutation of the registers v.
// http://en.wikipedia.org/wiki/Lehmer_code
int registers[6] = {UNWIND_X86_REG_NONE, UNWIND_X86_REG_NONE,
UNWIND_X86_REG_NONE, UNWIND_X86_REG_NONE,
UNWIND_X86_REG_NONE, UNWIND_X86_REG_NONE};
bool used[7] = {false, false, false, false, false, false, false};
for (uint32_t i = 0; i < register_count; i++) {
int renum = 0;
for (int j = 1; j < 7; j++) {
if (!used[j]) {
if (renum == permunreg[i]) {
registers[i] = j;
used[j] = true;
break;
}
renum++;
}
}
}
uint32_t saved_registers_offset = 1;
saved_registers_offset++;
for (int i = (sizeof(registers) / sizeof(int)) - 1; i >= 0; i--) {
switch (registers[i]) {
case UNWIND_X86_REG_NONE:
break;
case UNWIND_X86_REG_EBX:
case UNWIND_X86_REG_ECX:
case UNWIND_X86_REG_EDX:
case UNWIND_X86_REG_EDI:
case UNWIND_X86_REG_ESI:
case UNWIND_X86_REG_EBP:
row.SetRegisterLocationToAtCFAPlusOffset(
translate_to_eh_frame_regnum_i386(registers[i]),
wordsize * -saved_registers_offset, true);
saved_registers_offset++;
break;
}
}
}
unwind_plan.AppendRow(std::move(row));
return true;
} break;
case UNWIND_X86_MODE_DWARF: {
return false;
} break;
}
return false;
}
// DWARF register numbers from "DWARF for the ARM 64-bit Architecture (AArch64)"
// doc by ARM
enum arm64_eh_regnum {
x19 = 19,
x20 = 20,
x21 = 21,
x22 = 22,
x23 = 23,
x24 = 24,
x25 = 25,
x26 = 26,
x27 = 27,
x28 = 28,
fp = 29,
ra = 30,
sp = 31,
pc = 32,
// Compact unwind encodes d8-d15 but we don't have eh_frame / dwarf reg #'s
// for the 64-bit fp regs. Normally in DWARF it's context sensitive - so it
// knows it is fetching a 32- or 64-bit quantity from reg v8 to indicate s0
// or d0 - but the unwinder is operating at a lower level and we'd try to
// fetch 128 bits if we were told that v8 were stored on the stack...
v8 = 72,
v9 = 73,
v10 = 74,
v11 = 75,
v12 = 76,
v13 = 77,
v14 = 78,
v15 = 79,
};
enum arm_eh_regnum {
arm_r0 = 0,
arm_r1 = 1,
arm_r2 = 2,
arm_r3 = 3,
arm_r4 = 4,
arm_r5 = 5,
arm_r6 = 6,
arm_r7 = 7,
arm_r8 = 8,
arm_r9 = 9,
arm_r10 = 10,
arm_r11 = 11,
arm_r12 = 12,
arm_sp = 13,
arm_lr = 14,
arm_pc = 15,
arm_d0 = 256,
arm_d1 = 257,
arm_d2 = 258,
arm_d3 = 259,
arm_d4 = 260,
arm_d5 = 261,
arm_d6 = 262,
arm_d7 = 263,
arm_d8 = 264,
arm_d9 = 265,
arm_d10 = 266,
arm_d11 = 267,
arm_d12 = 268,
arm_d13 = 269,
arm_d14 = 270,
};
bool CompactUnwindInfo::CreateUnwindPlan_arm64(Target &target,
FunctionInfo &function_info,
UnwindPlan &unwind_plan,
Address pc_or_function_start) {
unwind_plan.SetSourceName("compact unwind info");
unwind_plan.SetSourcedFromCompiler(eLazyBoolYes);
unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
unwind_plan.SetRegisterKind(eRegisterKindEHFrame);
UnwindPlan::Row row;
const int wordsize = 8;
int mode = function_info.encoding & UNWIND_ARM64_MODE_MASK;
if (mode == UNWIND_ARM64_MODE_DWARF)
return false;
if (mode == UNWIND_ARM64_MODE_FRAMELESS) {
uint32_t stack_size =
(EXTRACT_BITS(function_info.encoding,
UNWIND_ARM64_FRAMELESS_STACK_SIZE_MASK)) *
16;
// Our previous Call Frame Address is the stack pointer plus the stack size
row.GetCFAValue().SetIsRegisterPlusOffset(arm64_eh_regnum::sp, stack_size);
// Our previous PC is in the LR
row.SetRegisterLocationToRegister(arm64_eh_regnum::pc, arm64_eh_regnum::ra,
true);
unwind_plan.AppendRow(std::move(row));
return true;
}
// Should not be possible
if (mode != UNWIND_ARM64_MODE_FRAME)
return false;
// mode == UNWIND_ARM64_MODE_FRAME
row.GetCFAValue().SetIsRegisterPlusOffset(arm64_eh_regnum::fp, 2 * wordsize);
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::fp, wordsize * -2,
true);
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::pc, wordsize * -1,
true);
row.SetRegisterLocationToIsCFAPlusOffset(arm64_eh_regnum::sp, 0, true);
int reg_pairs_saved_count = 1;
uint32_t saved_register_bits = function_info.encoding & 0xfff;
if (saved_register_bits & UNWIND_ARM64_FRAME_X19_X20_PAIR) {
int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x19, cfa_offset,
true);
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x20, cfa_offset,
true);
reg_pairs_saved_count++;
}
if (saved_register_bits & UNWIND_ARM64_FRAME_X21_X22_PAIR) {
int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x21, cfa_offset,
true);
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x22, cfa_offset,
true);
reg_pairs_saved_count++;
}
if (saved_register_bits & UNWIND_ARM64_FRAME_X23_X24_PAIR) {
int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x23, cfa_offset,
true);
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x24, cfa_offset,
true);
reg_pairs_saved_count++;
}
if (saved_register_bits & UNWIND_ARM64_FRAME_X25_X26_PAIR) {
int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x25, cfa_offset,
true);
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x26, cfa_offset,
true);
reg_pairs_saved_count++;
}
if (saved_register_bits & UNWIND_ARM64_FRAME_X27_X28_PAIR) {
int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x27, cfa_offset,
true);
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x28, cfa_offset,
true);
reg_pairs_saved_count++;
}
// If we use the v8-v15 regnums here, the unwinder will try to grab 128 bits
// off the stack;
// not sure if we have a good way to represent the 64-bitness of these saves.
if (saved_register_bits & UNWIND_ARM64_FRAME_D8_D9_PAIR) {
reg_pairs_saved_count++;
}
if (saved_register_bits & UNWIND_ARM64_FRAME_D10_D11_PAIR) {
reg_pairs_saved_count++;
}
if (saved_register_bits & UNWIND_ARM64_FRAME_D12_D13_PAIR) {
reg_pairs_saved_count++;
}
if (saved_register_bits & UNWIND_ARM64_FRAME_D14_D15_PAIR) {
reg_pairs_saved_count++;
}
unwind_plan.AppendRow(std::move(row));
return true;
}
bool CompactUnwindInfo::CreateUnwindPlan_armv7(Target &target,
FunctionInfo &function_info,
UnwindPlan &unwind_plan,
Address pc_or_function_start) {
unwind_plan.SetSourceName("compact unwind info");
unwind_plan.SetSourcedFromCompiler(eLazyBoolYes);
unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
unwind_plan.SetRegisterKind(eRegisterKindEHFrame);
UnwindPlan::Row row;
const int wordsize = 4;
int mode = function_info.encoding & UNWIND_ARM_MODE_MASK;
if (mode == UNWIND_ARM_MODE_DWARF)
return false;
uint32_t stack_adjust = (EXTRACT_BITS(function_info.encoding,
UNWIND_ARM_FRAME_STACK_ADJUST_MASK)) *
wordsize;
row.GetCFAValue().SetIsRegisterPlusOffset(arm_r7,
(2 * wordsize) + stack_adjust);
row.SetRegisterLocationToAtCFAPlusOffset(
arm_r7, (wordsize * -2) - stack_adjust, true);
row.SetRegisterLocationToAtCFAPlusOffset(
arm_pc, (wordsize * -1) - stack_adjust, true);
row.SetRegisterLocationToIsCFAPlusOffset(arm_sp, 0, true);
int cfa_offset = -stack_adjust - (2 * wordsize);
uint32_t saved_register_bits = function_info.encoding & 0xff;
if (saved_register_bits & UNWIND_ARM_FRAME_FIRST_PUSH_R6) {
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm_r6, cfa_offset, true);
}
if (saved_register_bits & UNWIND_ARM_FRAME_FIRST_PUSH_R5) {
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm_r5, cfa_offset, true);
}
if (saved_register_bits & UNWIND_ARM_FRAME_FIRST_PUSH_R4) {
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm_r4, cfa_offset, true);
}
if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R12) {
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm_r12, cfa_offset, true);
}
if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R11) {
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm_r11, cfa_offset, true);
}
if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R10) {
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm_r10, cfa_offset, true);
}
if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R9) {
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm_r9, cfa_offset, true);
}
if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R8) {
cfa_offset -= wordsize;
row.SetRegisterLocationToAtCFAPlusOffset(arm_r8, cfa_offset, true);
}
if (mode == UNWIND_ARM_MODE_FRAME_D) {
uint32_t d_reg_bits =
EXTRACT_BITS(function_info.encoding, UNWIND_ARM_FRAME_D_REG_COUNT_MASK);
switch (d_reg_bits) {
case 0:
// vpush {d8}
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d8, cfa_offset, true);
break;
case 1:
// vpush {d10}
// vpush {d8}
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d10, cfa_offset, true);
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d8, cfa_offset, true);
break;
case 2:
// vpush {d12}
// vpush {d10}
// vpush {d8}
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d12, cfa_offset, true);
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d10, cfa_offset, true);
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d8, cfa_offset, true);
break;
case 3:
// vpush {d14}
// vpush {d12}
// vpush {d10}
// vpush {d8}
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d14, cfa_offset, true);
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d12, cfa_offset, true);
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d10, cfa_offset, true);
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d8, cfa_offset, true);
break;
case 4:
// vpush {d14}
// vpush {d12}
// sp = (sp - 24) & (-16);
// vst {d8, d9, d10}
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d14, cfa_offset, true);
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d12, cfa_offset, true);
// FIXME we don't have a way to represent reg saves at an specific
// alignment short of
// coming up with some DWARF location description.
break;
case 5:
// vpush {d14}
// sp = (sp - 40) & (-16);
// vst {d8, d9, d10, d11}
// vst {d12}
cfa_offset -= 8;
row.SetRegisterLocationToAtCFAPlusOffset(arm_d14, cfa_offset, true);
// FIXME we don't have a way to represent reg saves at an specific
// alignment short of
// coming up with some DWARF location description.
break;
case 6:
// sp = (sp - 56) & (-16);
// vst {d8, d9, d10, d11}
// vst {d12, d13, d14}
// FIXME we don't have a way to represent reg saves at an specific
// alignment short of
// coming up with some DWARF location description.
break;
case 7:
// sp = (sp - 64) & (-16);
// vst {d8, d9, d10, d11}
// vst {d12, d13, d14, d15}
// FIXME we don't have a way to represent reg saves at an specific
// alignment short of
// coming up with some DWARF location description.
break;
}
}
unwind_plan.AppendRow(std::move(row));
return true;
}