Isolate::Init
bool Isolate::Init(Deserializer* des) { ASSERT(state_ != INITIALIZED);
ASSERT(Isolate::Current() == this);
TRACE_ISOLATE(init);
// The initialization process does not handle memory exhaustion.
DisallowAllocationFailure disallow_allocation_failure;
InitializeLoggingAndCounters();
InitializeDebugger();
// 内存分配器
memory_allocator_ = new MemoryAllocator(this);
code_range_ = new CodeRange(this);
// TODO:下面的未分析
// Safe after setting Heap::isolate_, initializing StackGuard and
// ensuring that Isolate::Current() == this.
heap_.SetStackLimits();
#define ASSIGN_ELEMENT(CamelName, hacker_name)
isolate_addresses_[Isolate::k##CamelName##Address] =
reinterpret_cast
(hacker_name##_address());
FOR_EACH_ISOLATE_ADDRESS_NAME(ASSIGN_ELEMENT)
#undef C
string_tracker_ = new StringTracker();
string_tracker_->isolate_ = this;
compilation_cache_ = new CompilationCache(this);
transcendental_cache_ = new TranscendentalCache();
keyed_lookup_cache_ = new KeyedLookupCache();
context_slot_cache_ = new ContextSlotCache();
descriptor_lookup_cache_ = new DescriptorLookupCache();
unicode_cache_ = new UnicodeCache();
inner_pointer_to_code_cache_ = new InnerPointerToCodeCache(this);
write_input_buffer_ = new StringInputBuffer();
global_handles_ = new GlobalHandles(this);
bootstrapper_ = new Bootstrapper();
handle_scope_implementer_ = new HandleScopeImplementer(this);
stub_cache_ = new StubCache(this, runtime_zone());
regexp_stack_ = new RegExpStack();
regexp_stack_->isolate_ = this;
date_cache_ = new DateCache();
// Enable logging before setting up the heap
logger_->SetUp();
CpuProfiler::SetUp();
HeapProfiler::SetUp();
// Initialize other runtime facilities
#if defined(USE_SIMULATOR)
#if defined(V8_TARGET_ARCH_ARM) || defined(V8_TARGET_ARCH_MIPS)
Simulator::Initialize(this);
#endif
#endif
{ // NOLINT
// Ensure that the thread has a valid stack guard. The v8::Locker object
// will ensure this too, but we don't have to use lockers if we are only
// using one thread.
ExecutionAccess lock(this);
stack_guard_.InitThread(lock);
}
// SetUp the object heap.
const bool create_heap_objects = (des == NULL);
ASSERT(!heap_.HasBeenSetUp());
if (!heap_.SetUp(create_heap_objects)) {
V8::SetFatalError();
return false;
}
if (create_heap_objects) {
// Terminate the cache array with the sentinel so we can iterate.
PushToPartialSnapshotCache(heap_.undefined_value());
}
InitializeThreadLocal();
bootstrapper_->Initialize(create_heap_objects);
builtins_.SetUp(create_heap_objects);
// Only preallocate on the first initialization.
if (FLAG_preallocate_message_memory && preallocated_message_space_ == NULL) {
// Start the thread which will set aside some memory.
PreallocatedMemoryThreadStart();
preallocated_message_space_ =
new NoAllocationStringAllocator(
preallocated_memory_thread_->data(),
preallocated_memory_thread_->length());
PreallocatedStorageInit(preallocated_memory_thread_->length() / 4);
}
if (FLAG_preemption) {
v8::Locker locker;
v8::Locker::StartPreemption(100);
}
#ifdef ENABLE_DEBUGGER_SUPPORT
debug_->SetUp(create_heap_objects);
#endif
// If we are deserializing, read the state into the now-empty heap.
if (!create_heap_objects) {
des->Deserialize();
}
stub_cache_->Initialize();
// Finish initialization of ThreadLocal after deserialization is done.
clear_pending_exception();
clear_pending_message();
clear_scheduled_exception();
// Deserializing may put strange things in the root array's copy of the
// stack guard.
heap_.SetStackLimits();
// Quiet the heap NaN if needed on target platform.
if (!create_heap_objects) Assembler::QuietNaN(heap_.nan_value());
deoptimizer_data_ = new DeoptimizerData;
runtime_profiler_ = new RuntimeProfiler(this);
runtime_profiler_->SetUp();
// If we are deserializing, log non-function code objects and compiled
// functions found in the snapshot.
if (create_heap_objects &&
(FLAG_log_code || FLAG_ll_prof || logger_->is_logging_code_events())) {
HandleScope scope;
LOG(this, LogCodeObjects());
LOG(this, LogCompiledFunctions());
}
CHECK_EQ(static_cast(OFFSET_OF(Isolate, state_)),
Internals::kIsolateStateOffset);
CHECK_EQ(static_cast(OFFSET_OF(Isolate, embedder_data_)),
Internals::kIsolateEmbedderDataOffset);
CHECK_EQ(static_cast(OFFSET_OF(Isolate, heap_.roots_)),
Internals::kIsolateRootsOffset);
state_ = INITIALIZED;
time_millis_at_init_ = OS::TimeCurrentMillis();
if (FLAG_parallel_recompilation) optimizing_compiler_thread_.Start();
return true;
}
