blob: dbd3a37dbb0762a948d8997042d733ed42e7f60b [file] [log] [blame]
/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "elf_writer_quick.h"
#include <unordered_map>
#include "base/logging.h"
#include "base/unix_file/fd_file.h"
#include "buffered_output_stream.h"
#include "driver/compiler_driver.h"
#include "dwarf.h"
#include "elf_builder.h"
#include "elf_file.h"
#include "elf_utils.h"
#include "file_output_stream.h"
#include "globals.h"
#include "leb128.h"
#include "oat.h"
#include "oat_writer.h"
#include "utils.h"
namespace art {
static void PushByte(std::vector<uint8_t>* buf, int data) {
buf->push_back(data & 0xff);
}
static uint32_t PushStr(std::vector<uint8_t>* buf, const char* str, const char* def = nullptr) {
if (str == nullptr) {
str = def;
}
uint32_t offset = buf->size();
for (size_t i = 0; str[i] != '\0'; ++i) {
buf->push_back(str[i]);
}
buf->push_back('\0');
return offset;
}
static uint32_t PushStr(std::vector<uint8_t>* buf, const std::string &str) {
uint32_t offset = buf->size();
buf->insert(buf->end(), str.begin(), str.end());
buf->push_back('\0');
return offset;
}
static void UpdateWord(std::vector<uint8_t>* buf, int offset, int data) {
(*buf)[offset+0] = data;
(*buf)[offset+1] = data >> 8;
(*buf)[offset+2] = data >> 16;
(*buf)[offset+3] = data >> 24;
}
static void PushHalf(std::vector<uint8_t>* buf, int data) {
buf->push_back(data & 0xff);
buf->push_back((data >> 8) & 0xff);
}
template <typename Elf_Word, typename Elf_Sword, typename Elf_Addr,
typename Elf_Dyn, typename Elf_Sym, typename Elf_Ehdr,
typename Elf_Phdr, typename Elf_Shdr>
bool ElfWriterQuick<Elf_Word, Elf_Sword, Elf_Addr, Elf_Dyn,
Elf_Sym, Elf_Ehdr, Elf_Phdr, Elf_Shdr>::Create(File* elf_file,
OatWriter* oat_writer,
const std::vector<const DexFile*>& dex_files,
const std::string& android_root,
bool is_host,
const CompilerDriver& driver) {
ElfWriterQuick elf_writer(driver, elf_file);
return elf_writer.Write(oat_writer, dex_files, android_root, is_host);
}
// Add patch information to this section. Each patch is a Elf_Word that
// identifies an offset from the start of the text section
static void ReservePatchSpace(const CompilerDriver* compiler_driver, std::vector<uint8_t>* buffer,
bool debug) {
size_t size =
compiler_driver->GetCodeToPatch().size() +
compiler_driver->GetMethodsToPatch().size() +
compiler_driver->GetClassesToPatch().size();
if (size == 0) {
if (debug) {
LOG(INFO) << "No patches to record";
}
return;
}
buffer->resize(size * sizeof(uintptr_t));
if (debug) {
LOG(INFO) << "Patches reserved for " << size;
}
}
std::vector<uint8_t>* ConstructCIEFrameX86(bool is_x86_64) {
std::vector<uint8_t>* cfi_info = new std::vector<uint8_t>;
// Length (will be filled in later in this routine).
if (is_x86_64) {
PushWord(cfi_info, 0xffffffff); // Indicates 64bit
PushWord(cfi_info, 0);
PushWord(cfi_info, 0);
} else {
PushWord(cfi_info, 0);
}
// CIE id: always 0.
if (is_x86_64) {
PushWord(cfi_info, 0);
PushWord(cfi_info, 0);
} else {
PushWord(cfi_info, 0);
}
// Version: always 1.
cfi_info->push_back(0x01);
// Augmentation: 'zR\0'
cfi_info->push_back(0x7a);
cfi_info->push_back(0x52);
cfi_info->push_back(0x0);
// Code alignment: 1.
EncodeUnsignedLeb128(1, cfi_info);
// Data alignment.
if (is_x86_64) {
EncodeSignedLeb128(-8, cfi_info);
} else {
EncodeSignedLeb128(-4, cfi_info);
}
// Return address register.
if (is_x86_64) {
// R16(RIP)
cfi_info->push_back(0x10);
} else {
// R8(EIP)
cfi_info->push_back(0x08);
}
// Augmentation length: 1.
cfi_info->push_back(1);
// Augmentation data.
if (is_x86_64) {
// 0x04 ((DW_EH_PE_absptr << 4) | DW_EH_PE_udata8).
cfi_info->push_back(0x04);
} else {
// 0x03 ((DW_EH_PE_absptr << 4) | DW_EH_PE_udata4).
cfi_info->push_back(0x03);
}
// Initial instructions.
if (is_x86_64) {
// DW_CFA_def_cfa R7(RSP) 8.
cfi_info->push_back(0x0c);
cfi_info->push_back(0x07);
cfi_info->push_back(0x08);
// DW_CFA_offset R16(RIP) 1 (* -8).
cfi_info->push_back(0x90);
cfi_info->push_back(0x01);
} else {
// DW_CFA_def_cfa R4(ESP) 4.
cfi_info->push_back(0x0c);
cfi_info->push_back(0x04);
cfi_info->push_back(0x04);
// DW_CFA_offset R8(EIP) 1 (* -4).
cfi_info->push_back(0x88);
cfi_info->push_back(0x01);
}
// Padding to a multiple of 4
while ((cfi_info->size() & 3) != 0) {
// DW_CFA_nop is encoded as 0.
cfi_info->push_back(0);
}
// Set the length of the CIE inside the generated bytes.
if (is_x86_64) {
uint32_t length = cfi_info->size() - 12;
UpdateWord(cfi_info, 4, length);
} else {
uint32_t length = cfi_info->size() - 4;
UpdateWord(cfi_info, 0, length);
}
return cfi_info;
}
std::vector<uint8_t>* ConstructCIEFrame(InstructionSet isa) {
switch (isa) {
case kX86:
return ConstructCIEFrameX86(false);
case kX86_64:
return ConstructCIEFrameX86(true);
default:
// Not implemented.
return nullptr;
}
}
class OatWriterWrapper : public CodeOutput {
public:
explicit OatWriterWrapper(OatWriter* oat_writer) : oat_writer_(oat_writer) {}
bool Write(OutputStream* out) OVERRIDE {
return oat_writer_->Write(out);
}
private:
OatWriter* oat_writer_;
};
template <typename Elf_Word, typename Elf_Sword, typename Elf_Addr,
typename Elf_Dyn, typename Elf_Sym, typename Elf_Ehdr,
typename Elf_Phdr, typename Elf_Shdr>
static void WriteDebugSymbols(const CompilerDriver* compiler_driver,
ElfBuilder<Elf_Word, Elf_Sword, Elf_Addr, Elf_Dyn,
Elf_Sym, Elf_Ehdr, Elf_Phdr, Elf_Shdr>* builder,
OatWriter* oat_writer);
template <typename Elf_Word, typename Elf_Sword, typename Elf_Addr,
typename Elf_Dyn, typename Elf_Sym, typename Elf_Ehdr,
typename Elf_Phdr, typename Elf_Shdr>
bool ElfWriterQuick<Elf_Word, Elf_Sword, Elf_Addr, Elf_Dyn,
Elf_Sym, Elf_Ehdr, Elf_Phdr, Elf_Shdr>::Write(OatWriter* oat_writer,
const std::vector<const DexFile*>& dex_files_unused,
const std::string& android_root_unused,
bool is_host_unused) {
constexpr bool debug = false;
const OatHeader& oat_header = oat_writer->GetOatHeader();
Elf_Word oat_data_size = oat_header.GetExecutableOffset();
uint32_t oat_exec_size = oat_writer->GetSize() - oat_data_size;
OatWriterWrapper wrapper(oat_writer);
std::unique_ptr<ElfBuilder<Elf_Word, Elf_Sword, Elf_Addr, Elf_Dyn,
Elf_Sym, Elf_Ehdr, Elf_Phdr, Elf_Shdr> > builder(
new ElfBuilder<Elf_Word, Elf_Sword, Elf_Addr, Elf_Dyn,
Elf_Sym, Elf_Ehdr, Elf_Phdr, Elf_Shdr>(
&wrapper,
elf_file_,
compiler_driver_->GetInstructionSet(),
0,
oat_data_size,
oat_data_size,
oat_exec_size,
compiler_driver_->GetCompilerOptions().GetIncludeDebugSymbols(),
debug));
if (!builder->Init()) {
return false;
}
if (compiler_driver_->GetCompilerOptions().GetIncludeDebugSymbols()) {
WriteDebugSymbols(compiler_driver_, builder.get(), oat_writer);
}
if (compiler_driver_->GetCompilerOptions().GetIncludePatchInformation()) {
ElfRawSectionBuilder<Elf_Word, Elf_Sword, Elf_Shdr> oat_patches(
".oat_patches", SHT_OAT_PATCH, 0, NULL, 0, sizeof(uintptr_t), sizeof(uintptr_t));
ReservePatchSpace(compiler_driver_, oat_patches.GetBuffer(), debug);
builder->RegisterRawSection(oat_patches);
}
return builder->Write();
}
class LineTableGenerator FINAL : public Leb128Encoder {
public:
LineTableGenerator(int line_base, int line_range, int opcode_base,
std::vector<uint8_t>* data, uintptr_t current_address,
size_t current_line)
: Leb128Encoder(data), line_base_(line_base), line_range_(line_range),
opcode_base_(opcode_base), current_address_(current_address),
current_line_(current_line), current_file_index_(0) {}
void PutDelta(unsigned delta_addr, int delta_line) {
current_line_ += delta_line;
current_address_ += delta_addr;
if (delta_line >= line_base_ && delta_line < line_base_ + line_range_) {
unsigned special_opcode = (delta_line - line_base_) +
(line_range_ * delta_addr) + opcode_base_;
if (special_opcode <= 255) {
PushByte(data_, special_opcode);
return;
}
}
// generate standart opcode for address advance
if (delta_addr != 0) {
PushByte(data_, DW_LNS_advance_pc);
PushBackUnsigned(delta_addr);
}
// generate standart opcode for line delta
if (delta_line != 0) {
PushByte(data_, DW_LNS_advance_line);
PushBackSigned(delta_line);
}
// generate standart opcode for new LTN entry
PushByte(data_, DW_LNS_copy);
}
void SetAddr(uintptr_t addr) {
if (current_address_ == addr) {
return;
}
current_address_ = addr;
PushByte(data_, 0); // extended opcode:
PushByte(data_, 1 + 4); // length: opcode_size + address_size
PushByte(data_, DW_LNE_set_address);
PushWord(data_, addr);
}
void SetLine(unsigned line) {
int delta_line = line - current_line_;
if (delta_line) {
current_line_ = line;
PushByte(data_, DW_LNS_advance_line);
PushBackSigned(delta_line);
}
}
void SetFile(unsigned file_index) {
if (current_file_index_ != file_index) {
current_file_index_ = file_index;
PushByte(data_, DW_LNS_set_file);
PushBackUnsigned(file_index);
}
}
void EndSequence() {
// End of Line Table Program
// 0(=ext), 1(len), DW_LNE_end_sequence
PushByte(data_, 0);
PushByte(data_, 1);
PushByte(data_, DW_LNE_end_sequence);
}
private:
const int line_base_;
const int line_range_;
const int opcode_base_;
uintptr_t current_address_;
size_t current_line_;
unsigned current_file_index_;
DISALLOW_COPY_AND_ASSIGN(LineTableGenerator);
};
// TODO: rewriting it using DexFile::DecodeDebugInfo needs unneeded stuff.
static void GetLineInfoForJava(const uint8_t* dbgstream, const SrcMap& pc2dex,
SrcMap* result, uint32_t start_pc = 0) {
if (dbgstream == nullptr) {
return;
}
int adjopcode;
uint32_t dex_offset = 0;
uint32_t java_line = DecodeUnsignedLeb128(&dbgstream);
// skip parameters
for (uint32_t param_count = DecodeUnsignedLeb128(&dbgstream); param_count != 0; --param_count) {
DecodeUnsignedLeb128(&dbgstream);
}
for (bool is_end = false; is_end == false; ) {
uint8_t opcode = *dbgstream;
dbgstream++;
switch (opcode) {
case DexFile::DBG_END_SEQUENCE:
is_end = true;
break;
case DexFile::DBG_ADVANCE_PC:
dex_offset += DecodeUnsignedLeb128(&dbgstream);
break;
case DexFile::DBG_ADVANCE_LINE:
java_line += DecodeSignedLeb128(&dbgstream);
break;
case DexFile::DBG_START_LOCAL:
case DexFile::DBG_START_LOCAL_EXTENDED:
DecodeUnsignedLeb128(&dbgstream);
DecodeUnsignedLeb128(&dbgstream);
DecodeUnsignedLeb128(&dbgstream);
if (opcode == DexFile::DBG_START_LOCAL_EXTENDED) {
DecodeUnsignedLeb128(&dbgstream);
}
break;
case DexFile::DBG_END_LOCAL:
case DexFile::DBG_RESTART_LOCAL:
DecodeUnsignedLeb128(&dbgstream);
break;
case DexFile::DBG_SET_PROLOGUE_END:
case DexFile::DBG_SET_EPILOGUE_BEGIN:
case DexFile::DBG_SET_FILE:
break;
default:
adjopcode = opcode - DexFile::DBG_FIRST_SPECIAL;
dex_offset += adjopcode / DexFile::DBG_LINE_RANGE;
java_line += DexFile::DBG_LINE_BASE + (adjopcode % DexFile::DBG_LINE_RANGE);
for (SrcMap::const_iterator found = pc2dex.FindByTo(dex_offset);
found != pc2dex.end() && found->to_ == static_cast<int32_t>(dex_offset);
found++) {
result->push_back({found->from_ + start_pc, static_cast<int32_t>(java_line)});
}
break;
}
}
}
/*
* @brief Generate the DWARF debug_info and debug_abbrev sections
* @param oat_writer The Oat file Writer.
* @param dbg_info Compilation unit information.
* @param dbg_abbrev Abbreviations used to generate dbg_info.
* @param dbg_str Debug strings.
*/
static void FillInCFIInformation(OatWriter* oat_writer,
std::vector<uint8_t>* dbg_info,
std::vector<uint8_t>* dbg_abbrev,
std::vector<uint8_t>* dbg_str,
std::vector<uint8_t>* dbg_line,
uint32_t text_section_offset) {
const std::vector<OatWriter::DebugInfo>& method_info = oat_writer->GetCFIMethodInfo();
uint32_t producer_str_offset = PushStr(dbg_str, "Android dex2oat");
// Create the debug_abbrev section with boilerplate information.
// We only care about low_pc and high_pc right now for the compilation
// unit and methods.
// Tag 1: Compilation unit: DW_TAG_compile_unit.
PushByte(dbg_abbrev, 1);
PushByte(dbg_abbrev, DW_TAG_compile_unit);
// There are children (the methods).
PushByte(dbg_abbrev, DW_CHILDREN_yes);
// DW_AT_producer DW_FORM_data1.
// REVIEW: we can get rid of dbg_str section if
// DW_FORM_string (immediate string) was used everywhere instead of
// DW_FORM_strp (ref to string from .debug_str section).
// DW_FORM_strp makes sense only if we reuse the strings.
PushByte(dbg_abbrev, DW_AT_producer);
PushByte(dbg_abbrev, DW_FORM_strp);
// DW_LANG_Java DW_FORM_data1.
PushByte(dbg_abbrev, DW_AT_language);
PushByte(dbg_abbrev, DW_FORM_data1);
// DW_AT_low_pc DW_FORM_addr.
PushByte(dbg_abbrev, DW_AT_low_pc);
PushByte(dbg_abbrev, DW_FORM_addr);
// DW_AT_high_pc DW_FORM_addr.
PushByte(dbg_abbrev, DW_AT_high_pc);
PushByte(dbg_abbrev, DW_FORM_addr);
if (dbg_line != nullptr) {
// DW_AT_stmt_list DW_FORM_sec_offset.
PushByte(dbg_abbrev, DW_AT_stmt_list);
PushByte(dbg_abbrev, DW_FORM_sec_offset);
}
// End of DW_TAG_compile_unit.
PushHalf(dbg_abbrev, 0);
// Tag 2: Compilation unit: DW_TAG_subprogram.
PushByte(dbg_abbrev, 2);
PushByte(dbg_abbrev, DW_TAG_subprogram);
// There are no children.
PushByte(dbg_abbrev, DW_CHILDREN_no);
// Name of the method.
PushByte(dbg_abbrev, DW_AT_name);
PushByte(dbg_abbrev, DW_FORM_strp);
// DW_AT_low_pc DW_FORM_addr.
PushByte(dbg_abbrev, DW_AT_low_pc);
PushByte(dbg_abbrev, DW_FORM_addr);
// DW_AT_high_pc DW_FORM_addr.
PushByte(dbg_abbrev, DW_AT_high_pc);
PushByte(dbg_abbrev, DW_FORM_addr);
// End of DW_TAG_subprogram.
PushHalf(dbg_abbrev, 0);
// Start the debug_info section with the header information
// 'unit_length' will be filled in later.
int cunit_length = dbg_info->size();
PushWord(dbg_info, 0);
// 'version' - 3.
PushHalf(dbg_info, 3);
// Offset into .debug_abbrev section (always 0).
PushWord(dbg_info, 0);
// Address size: 4.
PushByte(dbg_info, 4);
// Start the description for the compilation unit.
// This uses tag 1.
PushByte(dbg_info, 1);
// The producer is Android dex2oat.
PushWord(dbg_info, producer_str_offset);
// The language is Java.
PushByte(dbg_info, DW_LANG_Java);
// low_pc and high_pc.
uint32_t cunit_low_pc = 0 - 1;
uint32_t cunit_high_pc = 0;
int cunit_low_pc_pos = dbg_info->size();
PushWord(dbg_info, 0);
PushWord(dbg_info, 0);
if (dbg_line == nullptr) {
for (size_t i = 0; i < method_info.size(); ++i) {
const OatWriter::DebugInfo &dbg = method_info[i];
cunit_low_pc = std::min(cunit_low_pc, dbg.low_pc_);
cunit_high_pc = std::max(cunit_high_pc, dbg.high_pc_);
// Start a new TAG: subroutine (2).
PushByte(dbg_info, 2);
// Enter name, low_pc, high_pc.
PushWord(dbg_info, PushStr(dbg_str, dbg.method_name_));
PushWord(dbg_info, dbg.low_pc_ + text_section_offset);
PushWord(dbg_info, dbg.high_pc_ + text_section_offset);
}
} else {
// TODO: in gdb info functions <regexp> - reports Java functions, but
// source file is <unknown> because .debug_line is formed as one
// compilation unit. To fix this it is possible to generate
// a separate compilation unit for every distinct Java source.
// Each of the these compilation units can have several non-adjacent
// method ranges.
// Line number table offset
PushWord(dbg_info, dbg_line->size());
size_t lnt_length = dbg_line->size();
PushWord(dbg_line, 0);
PushHalf(dbg_line, 4); // LNT Version DWARF v4 => 4
size_t lnt_hdr_length = dbg_line->size();
PushWord(dbg_line, 0); // TODO: 64-bit uses 8-byte here
PushByte(dbg_line, 1); // minimum_instruction_length (ubyte)
PushByte(dbg_line, 1); // maximum_operations_per_instruction (ubyte) = always 1
PushByte(dbg_line, 1); // default_is_stmt (ubyte)
const int8_t LINE_BASE = -5;
PushByte(dbg_line, LINE_BASE); // line_base (sbyte)
const uint8_t LINE_RANGE = 14;
PushByte(dbg_line, LINE_RANGE); // line_range (ubyte)
const uint8_t OPCODE_BASE = 13;
PushByte(dbg_line, OPCODE_BASE); // opcode_base (ubyte)
// Standard_opcode_lengths (array of ubyte).
PushByte(dbg_line, 0); PushByte(dbg_line, 1); PushByte(dbg_line, 1);
PushByte(dbg_line, 1); PushByte(dbg_line, 1); PushByte(dbg_line, 0);
PushByte(dbg_line, 0); PushByte(dbg_line, 0); PushByte(dbg_line, 1);
PushByte(dbg_line, 0); PushByte(dbg_line, 0); PushByte(dbg_line, 1);
PushByte(dbg_line, 0); // include_directories (sequence of path names) = EMPTY
// File_names (sequence of file entries).
std::unordered_map<const char*, size_t> files;
for (size_t i = 0; i < method_info.size(); ++i) {
const OatWriter::DebugInfo &dbg = method_info[i];
// TODO: add package directory to the file name
const char* file_name = dbg.src_file_name_ == nullptr ? "null" : dbg.src_file_name_;
auto found = files.find(file_name);
if (found == files.end()) {
size_t file_index = 1 + files.size();
files[file_name] = file_index;
PushStr(dbg_line, file_name);
PushByte(dbg_line, 0); // include directory index = LEB128(0) - no directory
PushByte(dbg_line, 0); // modification time = LEB128(0) - NA
PushByte(dbg_line, 0); // file length = LEB128(0) - NA
}
}
PushByte(dbg_line, 0); // End of file_names.
// Set lnt header length.
UpdateWord(dbg_line, lnt_hdr_length, dbg_line->size() - lnt_hdr_length - 4);
// Generate Line Number Program code, one long program for all methods.
LineTableGenerator line_table_generator(LINE_BASE, LINE_RANGE, OPCODE_BASE,
dbg_line, 0, 1);
SrcMap pc2java_map;
for (size_t i = 0; i < method_info.size(); ++i) {
const OatWriter::DebugInfo &dbg = method_info[i];
const char* file_name = (dbg.src_file_name_ == nullptr) ? "null" : dbg.src_file_name_;
size_t file_index = files[file_name];
DCHECK_NE(file_index, 0U) << file_name;
cunit_low_pc = std::min(cunit_low_pc, dbg.low_pc_);
cunit_high_pc = std::max(cunit_high_pc, dbg.high_pc_);
// Start a new TAG: subroutine (2).
PushByte(dbg_info, 2);
// Enter name, low_pc, high_pc.
PushWord(dbg_info, PushStr(dbg_str, dbg.method_name_));
PushWord(dbg_info, dbg.low_pc_ + text_section_offset);
PushWord(dbg_info, dbg.high_pc_ + text_section_offset);
GetLineInfoForJava(dbg.dbgstream_, dbg.compiled_method_->GetSrcMappingTable(),
&pc2java_map, dbg.low_pc_);
pc2java_map.DeltaFormat({dbg.low_pc_, 1}, dbg.high_pc_);
if (!pc2java_map.empty()) {
line_table_generator.SetFile(file_index);
line_table_generator.SetAddr(dbg.low_pc_ + text_section_offset);
line_table_generator.SetLine(1);
for (auto& src_map_elem : pc2java_map) {
line_table_generator.PutDelta(src_map_elem.from_, src_map_elem.to_);
}
pc2java_map.clear();
}
}
// End Sequence should have the highest address set.
line_table_generator.SetAddr(cunit_high_pc + text_section_offset);
line_table_generator.EndSequence();
// set lnt length
UpdateWord(dbg_line, lnt_length, dbg_line->size() - lnt_length - 4);
}
// One byte terminator
PushByte(dbg_info, 0);
// Fill in cunit's low_pc and high_pc.
UpdateWord(dbg_info, cunit_low_pc_pos, cunit_low_pc + text_section_offset);
UpdateWord(dbg_info, cunit_low_pc_pos + 4, cunit_high_pc + text_section_offset);
// We have now walked all the methods. Fill in lengths.
UpdateWord(dbg_info, cunit_length, dbg_info->size() - cunit_length - 4);
}
template <typename Elf_Word, typename Elf_Sword, typename Elf_Addr,
typename Elf_Dyn, typename Elf_Sym, typename Elf_Ehdr,
typename Elf_Phdr, typename Elf_Shdr>
static void WriteDebugSymbols(const CompilerDriver* compiler_driver,
ElfBuilder<Elf_Word, Elf_Sword, Elf_Addr, Elf_Dyn,
Elf_Sym, Elf_Ehdr, Elf_Phdr, Elf_Shdr>* builder,
OatWriter* oat_writer) {
std::unique_ptr<std::vector<uint8_t>> cfi_info(
ConstructCIEFrame(compiler_driver->GetInstructionSet()));
Elf_Addr text_section_address = builder->text_builder_.section_.sh_addr;
// Iterate over the compiled methods.
const std::vector<OatWriter::DebugInfo>& method_info = oat_writer->GetCFIMethodInfo();
ElfSymtabBuilder<Elf_Word, Elf_Sword, Elf_Addr,
Elf_Sym, Elf_Shdr>* symtab = &builder->symtab_builder_;
for (auto it = method_info.begin(); it != method_info.end(); ++it) {
symtab->AddSymbol(it->method_name_, &builder->text_builder_, it->low_pc_, true,
it->high_pc_ - it->low_pc_, STB_GLOBAL, STT_FUNC);
// Include CFI for compiled method, if possible.
if (cfi_info.get() != nullptr) {
DCHECK(it->compiled_method_ != nullptr);
// Copy in the FDE, if present
const std::vector<uint8_t>* fde = it->compiled_method_->GetCFIInfo();
if (fde != nullptr) {
// Copy the information into cfi_info and then fix the address in the new copy.
int cur_offset = cfi_info->size();
cfi_info->insert(cfi_info->end(), fde->begin(), fde->end());
bool is_64bit = *(reinterpret_cast<const uint32_t*>(fde->data())) == 0xffffffff;
// Set the 'CIE_pointer' field.
uint64_t CIE_pointer = cur_offset + (is_64bit ? 12 : 4);
uint64_t offset_to_update = CIE_pointer;
if (is_64bit) {
(*cfi_info)[offset_to_update+0] = CIE_pointer;
(*cfi_info)[offset_to_update+1] = CIE_pointer >> 8;
(*cfi_info)[offset_to_update+2] = CIE_pointer >> 16;
(*cfi_info)[offset_to_update+3] = CIE_pointer >> 24;
(*cfi_info)[offset_to_update+4] = CIE_pointer >> 32;
(*cfi_info)[offset_to_update+5] = CIE_pointer >> 40;
(*cfi_info)[offset_to_update+6] = CIE_pointer >> 48;
(*cfi_info)[offset_to_update+7] = CIE_pointer >> 56;
} else {
(*cfi_info)[offset_to_update+0] = CIE_pointer;
(*cfi_info)[offset_to_update+1] = CIE_pointer >> 8;
(*cfi_info)[offset_to_update+2] = CIE_pointer >> 16;
(*cfi_info)[offset_to_update+3] = CIE_pointer >> 24;
}
// Set the 'initial_location' field.
offset_to_update += is_64bit ? 8 : 4;
if (is_64bit) {
const uint64_t quick_code_start = it->low_pc_ + text_section_address;
(*cfi_info)[offset_to_update+0] = quick_code_start;
(*cfi_info)[offset_to_update+1] = quick_code_start >> 8;
(*cfi_info)[offset_to_update+2] = quick_code_start >> 16;
(*cfi_info)[offset_to_update+3] = quick_code_start >> 24;
(*cfi_info)[offset_to_update+4] = quick_code_start >> 32;
(*cfi_info)[offset_to_update+5] = quick_code_start >> 40;
(*cfi_info)[offset_to_update+6] = quick_code_start >> 48;
(*cfi_info)[offset_to_update+7] = quick_code_start >> 56;
} else {
const uint32_t quick_code_start = it->low_pc_ + text_section_address;
(*cfi_info)[offset_to_update+0] = quick_code_start;
(*cfi_info)[offset_to_update+1] = quick_code_start >> 8;
(*cfi_info)[offset_to_update+2] = quick_code_start >> 16;
(*cfi_info)[offset_to_update+3] = quick_code_start >> 24;
}
}
}
}
bool hasCFI = (cfi_info.get() != nullptr);
bool hasLineInfo = false;
for (auto& dbg_info : oat_writer->GetCFIMethodInfo()) {
if (dbg_info.dbgstream_ != nullptr &&
!dbg_info.compiled_method_->GetSrcMappingTable().empty()) {
hasLineInfo = true;
break;
}
}
if (hasLineInfo || hasCFI) {
ElfRawSectionBuilder<Elf_Word, Elf_Sword, Elf_Shdr> debug_info(".debug_info",
SHT_PROGBITS,
0, nullptr, 0, 1, 0);
ElfRawSectionBuilder<Elf_Word, Elf_Sword, Elf_Shdr> debug_abbrev(".debug_abbrev",
SHT_PROGBITS,
0, nullptr, 0, 1, 0);
ElfRawSectionBuilder<Elf_Word, Elf_Sword, Elf_Shdr> debug_str(".debug_str",
SHT_PROGBITS,
0, nullptr, 0, 1, 0);
ElfRawSectionBuilder<Elf_Word, Elf_Sword, Elf_Shdr> debug_line(".debug_line",
SHT_PROGBITS,
0, nullptr, 0, 1, 0);
FillInCFIInformation(oat_writer, debug_info.GetBuffer(),
debug_abbrev.GetBuffer(), debug_str.GetBuffer(),
hasLineInfo ? debug_line.GetBuffer() : nullptr,
text_section_address);
builder->RegisterRawSection(debug_info);
builder->RegisterRawSection(debug_abbrev);
if (hasCFI) {
ElfRawSectionBuilder<Elf_Word, Elf_Sword, Elf_Shdr> eh_frame(".eh_frame",
SHT_PROGBITS,
SHF_ALLOC,
nullptr, 0, 4, 0);
eh_frame.SetBuffer(std::move(*cfi_info.get()));
builder->RegisterRawSection(eh_frame);
}
if (hasLineInfo) {
builder->RegisterRawSection(debug_line);
}
builder->RegisterRawSection(debug_str);
}
}
// Explicit instantiations
template class ElfWriterQuick<Elf32_Word, Elf32_Sword, Elf32_Addr, Elf32_Dyn,
Elf32_Sym, Elf32_Ehdr, Elf32_Phdr, Elf32_Shdr>;
template class ElfWriterQuick<Elf64_Word, Elf64_Sword, Elf64_Addr, Elf64_Dyn,
Elf64_Sym, Elf64_Ehdr, Elf64_Phdr, Elf64_Shdr>;
} // namespace art