| // Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| #include "vm/globals.h" |
| #if defined(DART_HOST_OS_LINUX) |
| |
| #include "vm/os.h" |
| |
| #include <dlfcn.h> // NOLINT |
| #include <elf.h> // NOLINT |
| #include <errno.h> // NOLINT |
| #include <fcntl.h> // NOLINT |
| #include <limits.h> // NOLINT |
| #include <malloc.h> // NOLINT |
| #include <sys/mman.h> // NOLINT |
| #include <sys/resource.h> // NOLINT |
| #include <sys/stat.h> // NOLINT |
| #include <sys/syscall.h> // NOLINT |
| #include <sys/time.h> // NOLINT |
| #include <sys/types.h> // NOLINT |
| #include <time.h> // NOLINT |
| #include <unistd.h> // NOLINT |
| |
| #include "platform/memory_sanitizer.h" |
| #include "platform/utils.h" |
| #include "vm/code_comments.h" |
| #include "vm/code_observers.h" |
| #include "vm/dart.h" |
| #include "vm/flags.h" |
| #include "vm/image_snapshot.h" |
| #include "vm/isolate.h" |
| #include "vm/lockers.h" |
| #include "vm/os_thread.h" |
| #include "vm/timeline.h" |
| #include "vm/zone.h" |
| |
| namespace dart { |
| |
| // Used to choose between Elf32/Elf64 types based on host archotecture bitsize. |
| #if defined(ARCH_IS_64_BIT) |
| #define ElfW(Type) Elf64_##Type |
| #else |
| #define ElfW(Type) Elf32_##Type |
| #endif |
| |
| // Missing from older versions of <elf.h>. |
| #if !defined(EM_RISCV) |
| #define EM_RISCV 243 |
| #endif |
| |
| #ifndef PRODUCT |
| |
| DEFINE_FLAG(bool, |
| generate_perf_events_symbols, |
| false, |
| "Generate events symbols for profiling with perf (disables dual " |
| "code mapping)"); |
| |
| DEFINE_FLAG(bool, |
| generate_perf_jitdump, |
| false, |
| "Generate jitdump file to use with perf-inject (disables dual code " |
| "mapping)"); |
| |
| DECLARE_FLAG(bool, write_protect_code); |
| DECLARE_FLAG(bool, write_protect_vm_isolate); |
| #if !defined(DART_PRECOMPILED_RUNTIME) |
| DECLARE_FLAG(bool, code_comments); |
| #endif |
| |
| // Linux CodeObservers. |
| |
| // Simple perf support: generate /tmp/perf-<pid>.map file that maps |
| // memory ranges to symbol names for JIT generated code. This allows |
| // perf-report to resolve addresses falling into JIT generated code. |
| // However perf-annotate does not work in this mode because JIT code |
| // is transient and does not exist anymore at the moment when you |
| // invoke perf-report. |
| class PerfCodeObserver : public CodeObserver { |
| public: |
| PerfCodeObserver() : out_file_(nullptr) { |
| Dart_FileOpenCallback file_open = Dart::file_open_callback(); |
| if (file_open == nullptr) { |
| return; |
| } |
| intptr_t pid = getpid(); |
| char* filename = OS::SCreate(nullptr, "/tmp/perf-%" Pd ".map", pid); |
| out_file_ = (*file_open)(filename, true); |
| free(filename); |
| } |
| |
| ~PerfCodeObserver() { |
| Dart_FileCloseCallback file_close = Dart::file_close_callback(); |
| if ((file_close == nullptr) || (out_file_ == nullptr)) { |
| return; |
| } |
| (*file_close)(out_file_); |
| } |
| |
| virtual bool IsActive() const { |
| return FLAG_generate_perf_events_symbols && (out_file_ != nullptr); |
| } |
| |
| virtual void Notify(const char* name, |
| uword base, |
| uword prologue_offset, |
| uword size, |
| bool optimized, |
| const CodeComments* comments) { |
| Dart_FileWriteCallback file_write = Dart::file_write_callback(); |
| if ((file_write == nullptr) || (out_file_ == nullptr)) { |
| return; |
| } |
| const char* marker = optimized ? "*" : ""; |
| char* buffer = |
| OS::SCreate(Thread::Current()->zone(), "%" Px " %" Px " %s%s\n", base, |
| size, marker, name); |
| { |
| MutexLocker ml(CodeObservers::mutex()); |
| (*file_write)(buffer, strlen(buffer), out_file_); |
| } |
| } |
| |
| private: |
| void* out_file_; |
| |
| DISALLOW_COPY_AND_ASSIGN(PerfCodeObserver); |
| }; |
| |
| // Code observer that generates a JITDUMP[1] file that can be interpreted by |
| // perf-inject to generate ELF images for JIT generated code objects, which |
| // allows both perf-report and perf-annotate to recognize them. |
| // |
| // Usage: |
| // |
| // $ perf record -k mono dart --generate-perf-jitdump benchmark.dart |
| // $ perf inject -j -i perf.data -o perf.data.jitted |
| // $ perf report -i perf.data.jitted |
| // |
| // [1] see linux/tools/perf/Documentation/jitdump-specification.txt for |
| // JITDUMP binary format. |
| class JitDumpCodeObserver : public CodeObserver { |
| public: |
| JitDumpCodeObserver() : pid_(getpid()) { |
| char* const filename = OS::SCreate(nullptr, "/tmp/jit-%" Pd ".dump", pid_); |
| const int fd = open(filename, O_CREAT | O_TRUNC | O_RDWR, 0666); |
| free(filename); |
| |
| if (fd == -1) { |
| return; |
| } |
| |
| // Map JITDUMP file, this mapping will be recorded by perf. This allows |
| // perf-inject to find this file later. |
| const long page_size = sysconf(_SC_PAGESIZE); // NOLINT(runtime/int) |
| if (page_size == -1) { |
| close(fd); |
| return; |
| } |
| |
| mapped_ = |
| mmap(nullptr, page_size, PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0); |
| if (mapped_ == nullptr) { |
| close(fd); |
| return; |
| } |
| mapped_size_ = page_size; |
| |
| out_file_ = fdopen(fd, "w+"); |
| if (out_file_ == nullptr) { |
| close(fd); |
| return; |
| } |
| |
| // Buffer the output to avoid high IO overheads - we are going to be |
| // writing all JIT generated code out. |
| setvbuf(out_file_, nullptr, _IOFBF, 2 * MB); |
| |
| // Disable code write protection and vm isolate write protection, because |
| // calling mprotect on the pages filled with JIT generated code objects |
| // confuses perf. |
| FLAG_write_protect_code = false; |
| FLAG_write_protect_vm_isolate = false; |
| |
| #if !defined(DART_PRECOMPILED_RUNTIME) |
| // Enable code comments. |
| FLAG_code_comments = true; |
| #endif |
| |
| // Write JITDUMP header. |
| WriteHeader(); |
| } |
| |
| ~JitDumpCodeObserver() { |
| if (mapped_ != nullptr) { |
| munmap(mapped_, mapped_size_); |
| mapped_ = nullptr; |
| } |
| |
| if (out_file_ != nullptr) { |
| fclose(out_file_); |
| out_file_ = nullptr; |
| } |
| } |
| |
| virtual bool IsActive() const { |
| return FLAG_generate_perf_jitdump && (out_file_ != nullptr); |
| } |
| |
| virtual void Notify(const char* name, |
| uword base, |
| uword prologue_offset, |
| uword size, |
| bool optimized, |
| const CodeComments* comments) { |
| MutexLocker ml(CodeObservers::mutex()); |
| |
| const char* marker = optimized ? "*" : ""; |
| char* buffer = OS::SCreate(Thread::Current()->zone(), "%s%s", marker, name); |
| const size_t name_length = strlen(buffer); |
| |
| WriteDebugInfo(base, comments); |
| |
| CodeLoadEvent ev; |
| ev.event = BaseEvent::kLoad; |
| ev.size = sizeof(ev) + (name_length + 1) + size; |
| ev.time_stamp = OS::GetCurrentMonotonicTicks(); |
| ev.process_id = getpid(); |
| ev.thread_id = syscall(SYS_gettid); |
| ev.vma = base; |
| ev.code_address = base; |
| ev.code_size = size; |
| ev.code_id = code_id_++; |
| |
| WriteFully(&ev, sizeof(ev)); |
| WriteFully(buffer, name_length + 1); |
| WriteFully(reinterpret_cast<void*>(base), size); |
| } |
| |
| private: |
| struct Header { |
| const uint32_t magic = 0x4A695444; |
| const uint32_t version = 1; |
| const uint32_t size = sizeof(Header); |
| uint32_t elf_mach_target; |
| const uint32_t reserved = 0xDEADBEEF; |
| uint32_t process_id; |
| uint64_t time_stamp; |
| const uint64_t flags = 0; |
| }; |
| |
| struct BaseEvent { |
| enum Event { |
| kLoad = 0, |
| kMove = 1, |
| kDebugInfo = 2, |
| kClose = 3, |
| kUnwindingInfo = 4 |
| }; |
| |
| uint32_t event; |
| uint32_t size; |
| uint64_t time_stamp; |
| }; |
| |
| struct CodeLoadEvent : BaseEvent { |
| uint32_t process_id; |
| uint32_t thread_id; |
| uint64_t vma; |
| uint64_t code_address; |
| uint64_t code_size; |
| uint64_t code_id; |
| }; |
| |
| struct DebugInfoEvent : BaseEvent { |
| uint64_t address; |
| uint64_t entry_count; |
| // DebugInfoEntry entries[entry_count_]; |
| }; |
| |
| struct DebugInfoEntry { |
| uint64_t address; |
| int32_t line_number; |
| int32_t column; |
| // Followed by nul-terminated name. |
| }; |
| |
| static uint32_t GetElfMachineArchitecture() { |
| #if TARGET_ARCH_IA32 |
| return EM_386; |
| #elif TARGET_ARCH_X64 |
| return EM_X86_64; |
| #elif TARGET_ARCH_ARM |
| return EM_ARM; |
| #elif TARGET_ARCH_ARM64 |
| return EM_AARCH64; |
| #elif TARGET_ARCH_RISCV32 || TARGET_ARCH_RISCV64 |
| return EM_RISCV; |
| #else |
| UNREACHABLE(); |
| return 0; |
| #endif |
| } |
| |
| void WriteDebugInfo(uword base, const CodeComments* comments) { |
| if (comments == nullptr || comments->Length() == 0) { |
| return; |
| } |
| |
| // Open the comments file for the given code object. |
| // Note: for some reason we can't emit all comments into a single file |
| // the mapping between PCs and lines goes out of sync (might be |
| // perf-annotate bug). |
| char* comments_file_name = |
| OS::SCreate(nullptr, "/tmp/jit-%" Pd "-%" Pd ".cmts", pid_, code_id_); |
| const intptr_t filename_length = strlen(comments_file_name); |
| FILE* comments_file = fopen(comments_file_name, "w"); |
| setvbuf(comments_file, nullptr, _IOFBF, 2 * MB); |
| |
| // Count the number of DebugInfoEntry we are going to emit: one |
| // per PC. |
| intptr_t entry_count = 0; |
| for (uint64_t i = 0, len = comments->Length(); i < len;) { |
| const intptr_t pc_offset = comments->PCOffsetAt(i); |
| while (i < len && comments->PCOffsetAt(i) == pc_offset) { |
| i++; |
| } |
| entry_count++; |
| } |
| |
| DebugInfoEvent info; |
| info.event = BaseEvent::kDebugInfo; |
| info.time_stamp = OS::GetCurrentMonotonicTicks(); |
| info.address = base; |
| info.entry_count = entry_count; |
| info.size = sizeof(info) + |
| entry_count * (sizeof(DebugInfoEntry) + filename_length + 1); |
| const int32_t padding = Utils::RoundUp(info.size, 8) - info.size; |
| info.size += padding; |
| |
| // Write out DebugInfoEvent record followed by entry_count DebugInfoEntry |
| // records. |
| WriteFully(&info, sizeof(info)); |
| intptr_t line_number = 0; // Line number within comments_file. |
| for (intptr_t i = 0, len = comments->Length(); i < len;) { |
| const intptr_t pc_offset = comments->PCOffsetAt(i); |
| while (i < len && comments->PCOffsetAt(i) == pc_offset) { |
| line_number += WriteLn(comments_file, comments->CommentAt(i)); |
| i++; |
| } |
| DebugInfoEntry entry; |
| entry.address = base + pc_offset + sizeof(ElfW(Ehdr)); |
| entry.line_number = line_number; |
| entry.column = 0; |
| WriteFully(&entry, sizeof(entry)); |
| WriteFully(comments_file_name, filename_length + 1); |
| } |
| |
| // Write out the padding. |
| const char padding_bytes[8] = {0}; |
| WriteFully(padding_bytes, padding); |
| |
| fclose(comments_file); |
| free(comments_file_name); |
| } |
| |
| void WriteHeader() { |
| Header header; |
| header.elf_mach_target = GetElfMachineArchitecture(); |
| header.process_id = getpid(); |
| header.time_stamp = OS::GetCurrentTimeMicros(); |
| WriteFully(&header, sizeof(header)); |
| } |
| |
| // Returns number of new-lines written. |
| intptr_t WriteLn(FILE* f, const char* comment) { |
| fputs(comment, f); |
| fputc('\n', f); |
| |
| intptr_t line_count = 1; |
| while ((comment = strstr(comment, "\n")) != nullptr) { |
| line_count++; |
| } |
| return line_count; |
| } |
| |
| void WriteFully(const void* buffer, size_t size) { |
| const char* ptr = static_cast<const char*>(buffer); |
| while (size > 0) { |
| const size_t written = fwrite(ptr, 1, size, out_file_); |
| if (written == 0) { |
| UNREACHABLE(); |
| break; |
| } |
| size -= written; |
| ptr += written; |
| } |
| } |
| |
| const intptr_t pid_; |
| |
| FILE* out_file_ = nullptr; |
| void* mapped_ = nullptr; |
| long mapped_size_ = 0; // NOLINT(runtime/int) |
| |
| intptr_t code_id_ = 0; |
| |
| DISALLOW_COPY_AND_ASSIGN(JitDumpCodeObserver); |
| }; |
| |
| #endif // !PRODUCT |
| |
| intptr_t OS::ProcessId() { |
| return static_cast<intptr_t>(getpid()); |
| } |
| |
| static bool LocalTime(int64_t seconds_since_epoch, tm* tm_result) { |
| time_t seconds = static_cast<time_t>(seconds_since_epoch); |
| if (seconds != seconds_since_epoch) return false; |
| struct tm* error_code = localtime_r(&seconds, tm_result); |
| return error_code != nullptr; |
| } |
| |
| const char* OS::GetTimeZoneName(int64_t seconds_since_epoch) { |
| tm decomposed; |
| bool succeeded = LocalTime(seconds_since_epoch, &decomposed); |
| // If unsuccessful, return an empty string like V8 does. |
| return (succeeded && (decomposed.tm_zone != nullptr)) ? decomposed.tm_zone |
| : ""; |
| } |
| |
| int OS::GetTimeZoneOffsetInSeconds(int64_t seconds_since_epoch) { |
| tm decomposed; |
| bool succeeded = LocalTime(seconds_since_epoch, &decomposed); |
| // Even if the offset was 24 hours it would still easily fit into 32 bits. |
| // If unsuccessful, return zero like V8 does. |
| return succeeded ? static_cast<int>(decomposed.tm_gmtoff) : 0; |
| } |
| |
| int64_t OS::GetCurrentTimeMillis() { |
| return GetCurrentTimeMicros() / 1000; |
| } |
| |
| int64_t OS::GetCurrentTimeMicros() { |
| // gettimeofday has microsecond resolution. |
| struct timeval tv; |
| if (gettimeofday(&tv, nullptr) < 0) { |
| UNREACHABLE(); |
| return 0; |
| } |
| return (static_cast<int64_t>(tv.tv_sec) * 1000000) + tv.tv_usec; |
| } |
| |
| int64_t OS::GetCurrentMonotonicTicks() { |
| struct timespec ts; |
| if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0) { |
| UNREACHABLE(); |
| return 0; |
| } |
| // Convert to nanoseconds. |
| int64_t result = ts.tv_sec; |
| result *= kNanosecondsPerSecond; |
| result += ts.tv_nsec; |
| return result; |
| } |
| |
| int64_t OS::GetCurrentMonotonicFrequency() { |
| return kNanosecondsPerSecond; |
| } |
| |
| int64_t OS::GetCurrentMonotonicMicros() { |
| int64_t ticks = GetCurrentMonotonicTicks(); |
| ASSERT(GetCurrentMonotonicFrequency() == kNanosecondsPerSecond); |
| return ticks / kNanosecondsPerMicrosecond; |
| } |
| |
| int64_t OS::GetCurrentThreadCPUMicros() { |
| struct timespec ts; |
| if (clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts) != 0) { |
| UNREACHABLE(); |
| return -1; |
| } |
| int64_t result = ts.tv_sec; |
| result *= kMicrosecondsPerSecond; |
| result += (ts.tv_nsec / kNanosecondsPerMicrosecond); |
| return result; |
| } |
| |
| int64_t OS::GetCurrentMonotonicMicrosForTimeline() { |
| #if defined(SUPPORT_TIMELINE) |
| if (Timeline::recorder_discards_clock_values()) return -1; |
| return GetCurrentMonotonicMicros(); |
| #else |
| return -1; |
| #endif |
| } |
| |
| // TODO(5411554): May need to hoist these architecture dependent code |
| // into a architecture specific file e.g: os_ia32_linux.cc |
| intptr_t OS::ActivationFrameAlignment() { |
| #if defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_X64) || \ |
| defined(TARGET_ARCH_ARM64) || defined(TARGET_ARCH_RISCV32) || \ |
| defined(TARGET_ARCH_RISCV64) |
| const int kMinimumAlignment = 16; |
| #elif defined(TARGET_ARCH_ARM) |
| const int kMinimumAlignment = 8; |
| #else |
| #error Unsupported architecture. |
| #endif |
| intptr_t alignment = kMinimumAlignment; |
| // TODO(5411554): Allow overriding default stack alignment for |
| // testing purposes. |
| // Flags::DebugIsInt("stackalign", &alignment); |
| ASSERT(Utils::IsPowerOfTwo(alignment)); |
| ASSERT(alignment >= kMinimumAlignment); |
| return alignment; |
| } |
| |
| int OS::NumberOfAvailableProcessors() { |
| return sysconf(_SC_NPROCESSORS_ONLN); |
| } |
| |
| void OS::Sleep(int64_t millis) { |
| int64_t micros = millis * kMicrosecondsPerMillisecond; |
| SleepMicros(micros); |
| } |
| |
| void OS::SleepMicros(int64_t micros) { |
| struct timespec req; // requested. |
| struct timespec rem; // remainder. |
| int64_t seconds = micros / kMicrosecondsPerSecond; |
| micros = micros - seconds * kMicrosecondsPerSecond; |
| int64_t nanos = micros * kNanosecondsPerMicrosecond; |
| req.tv_sec = seconds; |
| req.tv_nsec = nanos; |
| while (true) { |
| int r = nanosleep(&req, &rem); |
| if (r == 0) { |
| break; |
| } |
| // We should only ever see an interrupt error. |
| ASSERT(errno == EINTR); |
| // Copy remainder into requested and repeat. |
| req = rem; |
| } |
| } |
| |
| // TODO(regis): Function called only from the simulator. |
| void OS::DebugBreak() { |
| __builtin_trap(); |
| } |
| |
| DART_NOINLINE uintptr_t OS::GetProgramCounter() { |
| return reinterpret_cast<uintptr_t>( |
| __builtin_extract_return_addr(__builtin_return_address(0))); |
| } |
| |
| void OS::Print(const char* format, ...) { |
| va_list args; |
| va_start(args, format); |
| VFPrint(stdout, format, args); |
| va_end(args); |
| } |
| |
| void OS::VFPrint(FILE* stream, const char* format, va_list args) { |
| vfprintf(stream, format, args); |
| fflush(stream); |
| } |
| |
| char* OS::SCreate(Zone* zone, const char* format, ...) { |
| va_list args; |
| va_start(args, format); |
| char* buffer = VSCreate(zone, format, args); |
| va_end(args); |
| return buffer; |
| } |
| |
| char* OS::VSCreate(Zone* zone, const char* format, va_list args) { |
| // Measure. |
| va_list measure_args; |
| va_copy(measure_args, args); |
| intptr_t len = Utils::VSNPrint(nullptr, 0, format, measure_args); |
| va_end(measure_args); |
| |
| char* buffer; |
| if (zone != nullptr) { |
| buffer = zone->Alloc<char>(len + 1); |
| } else { |
| buffer = reinterpret_cast<char*>(malloc(len + 1)); |
| } |
| ASSERT(buffer != nullptr); |
| |
| // Print. |
| va_list print_args; |
| va_copy(print_args, args); |
| Utils::VSNPrint(buffer, len + 1, format, print_args); |
| va_end(print_args); |
| return buffer; |
| } |
| |
| bool OS::StringToInt64(const char* str, int64_t* value) { |
| ASSERT(str != nullptr && strlen(str) > 0 && value != nullptr); |
| int32_t base = 10; |
| char* endptr; |
| int i = 0; |
| if (str[0] == '-') { |
| i = 1; |
| } else if (str[0] == '+') { |
| i = 1; |
| } |
| if ((str[i] == '0') && (str[i + 1] == 'x' || str[i + 1] == 'X') && |
| (str[i + 2] != '\0')) { |
| base = 16; |
| } |
| errno = 0; |
| if (base == 16) { |
| // Unsigned 64-bit hexadecimal integer literals are allowed but |
| // immediately interpreted as signed 64-bit integers. |
| *value = static_cast<int64_t>(strtoull(str, &endptr, base)); |
| } else { |
| *value = strtoll(str, &endptr, base); |
| } |
| return ((errno == 0) && (endptr != str) && (*endptr == 0)); |
| } |
| |
| void OS::RegisterCodeObservers() { |
| #ifndef PRODUCT |
| if (FLAG_generate_perf_events_symbols) { |
| CodeObservers::Register(new PerfCodeObserver); |
| } |
| |
| if (FLAG_generate_perf_jitdump) { |
| CodeObservers::Register(new JitDumpCodeObserver); |
| } |
| #endif // !PRODUCT |
| } |
| |
| void OS::PrintErr(const char* format, ...) { |
| va_list args; |
| va_start(args, format); |
| VFPrint(stderr, format, args); |
| va_end(args); |
| } |
| |
| void OS::Init() {} |
| |
| void OS::Cleanup() {} |
| |
| void OS::PrepareToAbort() {} |
| |
| void OS::Abort() { |
| PrepareToAbort(); |
| abort(); |
| } |
| |
| void OS::Exit(int code) { |
| exit(code); |
| } |
| |
| OS::BuildId OS::GetAppBuildId(const uint8_t* snapshot_instructions) { |
| // First return the build ID information from the instructions image if |
| // available. |
| const Image instructions_image(snapshot_instructions); |
| if (auto* const image_build_id = instructions_image.build_id()) { |
| return {instructions_image.build_id_length(), image_build_id}; |
| } |
| const uint8_t* dso_base = GetAppDSOBase(snapshot_instructions); |
| const ElfW(Ehdr) & elf_header = |
| *reinterpret_cast<const ElfW(Ehdr)*>(dso_base); |
| const ElfW(Phdr)* const phdr_array = |
| reinterpret_cast<const ElfW(Phdr)*>(dso_base + elf_header.e_phoff); |
| for (intptr_t i = 0; i < elf_header.e_phnum; i++) { |
| const ElfW(Phdr) & header = phdr_array[i]; |
| if (header.p_type != PT_NOTE) continue; |
| if ((header.p_flags & PF_R) != PF_R) continue; |
| const uint8_t* const note_addr = dso_base + header.p_vaddr; |
| const Elf32_Nhdr& note_header = |
| *reinterpret_cast<const Elf32_Nhdr*>(note_addr); |
| if (note_header.n_type != NT_GNU_BUILD_ID) continue; |
| const char* const note_contents = |
| reinterpret_cast<const char*>(note_addr + sizeof(Elf32_Nhdr)); |
| // The note name contains the null terminator as well. |
| if (note_header.n_namesz != strlen(ELF_NOTE_GNU) + 1) continue; |
| if (strncmp(ELF_NOTE_GNU, note_contents, note_header.n_namesz) == 0) { |
| return {static_cast<intptr_t>(note_header.n_descsz), |
| reinterpret_cast<const uint8_t*>(note_contents + |
| note_header.n_namesz)}; |
| } |
| } |
| return {0, nullptr}; |
| } |
| |
| } // namespace dart |
| |
| #endif // defined(DART_HOST_OS_LINUX) |