blob: 56c08b5b53679d44e4adaa9652f460b5c5492817 [file] [log] [blame]
// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/execution.h"
#include "src/bootstrapper.h"
#include "src/codegen.h"
#include "src/isolate-inl.h"
#include "src/messages.h"
#include "src/vm-state-inl.h"
namespace v8 {
namespace internal {
StackGuard::StackGuard()
: isolate_(NULL) {
}
void StackGuard::set_interrupt_limits(const ExecutionAccess& lock) {
DCHECK(isolate_ != NULL);
thread_local_.set_jslimit(kInterruptLimit);
thread_local_.set_climit(kInterruptLimit);
isolate_->heap()->SetStackLimits();
}
void StackGuard::reset_limits(const ExecutionAccess& lock) {
DCHECK(isolate_ != NULL);
thread_local_.set_jslimit(thread_local_.real_jslimit_);
thread_local_.set_climit(thread_local_.real_climit_);
isolate_->heap()->SetStackLimits();
}
static void PrintDeserializedCodeInfo(Handle<JSFunction> function) {
if (function->code() == function->shared()->code() &&
function->shared()->deserialized()) {
PrintF("[Running deserialized script");
Object* script = function->shared()->script();
if (script->IsScript()) {
Object* name = Script::cast(script)->name();
if (name->IsString()) {
PrintF(": %s", String::cast(name)->ToCString().get());
}
}
PrintF("]\n");
}
}
namespace {
MUST_USE_RESULT MaybeHandle<Object> Invoke(Isolate* isolate, bool is_construct,
Handle<Object> target,
Handle<Object> receiver, int argc,
Handle<Object> args[],
Handle<Object> new_target) {
DCHECK(!receiver->IsJSGlobalObject());
#ifdef USE_SIMULATOR
// Simulators use separate stacks for C++ and JS. JS stack overflow checks
// are performed whenever a JS function is called. However, it can be the case
// that the C++ stack grows faster than the JS stack, resulting in an overflow
// there. Add a check here to make that less likely.
StackLimitCheck check(isolate);
if (check.HasOverflowed()) {
isolate->StackOverflow();
isolate->ReportPendingMessages();
return MaybeHandle<Object>();
}
#endif
// api callbacks can be called directly.
if (target->IsJSFunction()) {
Handle<JSFunction> function = Handle<JSFunction>::cast(target);
if ((!is_construct || function->IsConstructor()) &&
function->shared()->IsApiFunction()) {
SaveContext save(isolate);
isolate->set_context(function->context());
DCHECK(function->context()->global_object()->IsJSGlobalObject());
if (is_construct) receiver = isolate->factory()->the_hole_value();
auto value = Builtins::InvokeApiFunction(
isolate, is_construct, function, receiver, argc, args,
Handle<HeapObject>::cast(new_target));
bool has_exception = value.is_null();
DCHECK(has_exception == isolate->has_pending_exception());
if (has_exception) {
isolate->ReportPendingMessages();
return MaybeHandle<Object>();
} else {
isolate->clear_pending_message();
}
return value;
}
}
// Entering JavaScript.
VMState<JS> state(isolate);
CHECK(AllowJavascriptExecution::IsAllowed(isolate));
if (!ThrowOnJavascriptExecution::IsAllowed(isolate)) {
isolate->ThrowIllegalOperation();
isolate->ReportPendingMessages();
return MaybeHandle<Object>();
}
// Placeholder for return value.
Object* value = NULL;
typedef Object* (*JSEntryFunction)(Object* new_target, Object* target,
Object* receiver, int argc,
Object*** args);
Handle<Code> code = is_construct
? isolate->factory()->js_construct_entry_code()
: isolate->factory()->js_entry_code();
{
// Save and restore context around invocation and block the
// allocation of handles without explicit handle scopes.
SaveContext save(isolate);
SealHandleScope shs(isolate);
JSEntryFunction stub_entry = FUNCTION_CAST<JSEntryFunction>(code->entry());
if (FLAG_clear_exceptions_on_js_entry) isolate->clear_pending_exception();
// Call the function through the right JS entry stub.
Object* orig_func = *new_target;
Object* func = *target;
Object* recv = *receiver;
Object*** argv = reinterpret_cast<Object***>(args);
if (FLAG_profile_deserialization && target->IsJSFunction()) {
PrintDeserializedCodeInfo(Handle<JSFunction>::cast(target));
}
RuntimeCallTimerScope timer(isolate, &RuntimeCallStats::JS_Execution);
TRACE_EVENT_RUNTIME_CALL_STATS_TRACING_SCOPED(
isolate, &tracing::TraceEventStatsTable::JS_Execution);
value = CALL_GENERATED_CODE(isolate, stub_entry, orig_func, func, recv,
argc, argv);
}
#ifdef VERIFY_HEAP
if (FLAG_verify_heap) {
value->ObjectVerify();
}
#endif
// Update the pending exception flag and return the value.
bool has_exception = value->IsException(isolate);
DCHECK(has_exception == isolate->has_pending_exception());
if (has_exception) {
isolate->ReportPendingMessages();
return MaybeHandle<Object>();
} else {
isolate->clear_pending_message();
}
return Handle<Object>(value, isolate);
}
} // namespace
// static
MaybeHandle<Object> Execution::Call(Isolate* isolate, Handle<Object> callable,
Handle<Object> receiver, int argc,
Handle<Object> argv[]) {
// Convert calls on global objects to be calls on the global
// receiver instead to avoid having a 'this' pointer which refers
// directly to a global object.
if (receiver->IsJSGlobalObject()) {
receiver =
handle(Handle<JSGlobalObject>::cast(receiver)->global_proxy(), isolate);
}
return Invoke(isolate, false, callable, receiver, argc, argv,
isolate->factory()->undefined_value());
}
// static
MaybeHandle<Object> Execution::New(Handle<JSFunction> constructor, int argc,
Handle<Object> argv[]) {
return New(constructor->GetIsolate(), constructor, constructor, argc, argv);
}
// static
MaybeHandle<Object> Execution::New(Isolate* isolate, Handle<Object> constructor,
Handle<Object> new_target, int argc,
Handle<Object> argv[]) {
return Invoke(isolate, true, constructor,
isolate->factory()->undefined_value(), argc, argv, new_target);
}
MaybeHandle<Object> Execution::TryCall(Isolate* isolate,
Handle<Object> callable,
Handle<Object> receiver, int argc,
Handle<Object> args[],
MaybeHandle<Object>* exception_out) {
bool is_termination = false;
MaybeHandle<Object> maybe_result;
if (exception_out != NULL) *exception_out = MaybeHandle<Object>();
// Enter a try-block while executing the JavaScript code. To avoid
// duplicate error printing it must be non-verbose. Also, to avoid
// creating message objects during stack overflow we shouldn't
// capture messages.
{
v8::TryCatch catcher(reinterpret_cast<v8::Isolate*>(isolate));
catcher.SetVerbose(false);
catcher.SetCaptureMessage(false);
maybe_result = Call(isolate, callable, receiver, argc, args);
if (maybe_result.is_null()) {
DCHECK(catcher.HasCaught());
DCHECK(isolate->has_pending_exception());
DCHECK(isolate->external_caught_exception());
if (isolate->pending_exception() ==
isolate->heap()->termination_exception()) {
is_termination = true;
} else {
if (exception_out != NULL) {
*exception_out = v8::Utils::OpenHandle(*catcher.Exception());
}
}
isolate->OptionalRescheduleException(true);
}
DCHECK(!isolate->has_pending_exception());
}
// Re-request terminate execution interrupt to trigger later.
if (is_termination) isolate->stack_guard()->RequestTerminateExecution();
return maybe_result;
}
void StackGuard::SetStackLimit(uintptr_t limit) {
ExecutionAccess access(isolate_);
// If the current limits are special (e.g. due to a pending interrupt) then
// leave them alone.
uintptr_t jslimit = SimulatorStack::JsLimitFromCLimit(isolate_, limit);
if (thread_local_.jslimit() == thread_local_.real_jslimit_) {
thread_local_.set_jslimit(jslimit);
}
if (thread_local_.climit() == thread_local_.real_climit_) {
thread_local_.set_climit(limit);
}
thread_local_.real_climit_ = limit;
thread_local_.real_jslimit_ = jslimit;
}
void StackGuard::AdjustStackLimitForSimulator() {
ExecutionAccess access(isolate_);
uintptr_t climit = thread_local_.real_climit_;
// If the current limits are special (e.g. due to a pending interrupt) then
// leave them alone.
uintptr_t jslimit = SimulatorStack::JsLimitFromCLimit(isolate_, climit);
if (thread_local_.jslimit() == thread_local_.real_jslimit_) {
thread_local_.set_jslimit(jslimit);
isolate_->heap()->SetStackLimits();
}
}
void StackGuard::EnableInterrupts() {
ExecutionAccess access(isolate_);
if (has_pending_interrupts(access)) {
set_interrupt_limits(access);
}
}
void StackGuard::DisableInterrupts() {
ExecutionAccess access(isolate_);
reset_limits(access);
}
void StackGuard::PushPostponeInterruptsScope(PostponeInterruptsScope* scope) {
ExecutionAccess access(isolate_);
// Intercept already requested interrupts.
int intercepted = thread_local_.interrupt_flags_ & scope->intercept_mask_;
scope->intercepted_flags_ = intercepted;
thread_local_.interrupt_flags_ &= ~intercepted;
if (!has_pending_interrupts(access)) reset_limits(access);
// Add scope to the chain.
scope->prev_ = thread_local_.postpone_interrupts_;
thread_local_.postpone_interrupts_ = scope;
}
void StackGuard::PopPostponeInterruptsScope() {
ExecutionAccess access(isolate_);
PostponeInterruptsScope* top = thread_local_.postpone_interrupts_;
// Make intercepted interrupts active.
DCHECK((thread_local_.interrupt_flags_ & top->intercept_mask_) == 0);
thread_local_.interrupt_flags_ |= top->intercepted_flags_;
if (has_pending_interrupts(access)) set_interrupt_limits(access);
// Remove scope from chain.
thread_local_.postpone_interrupts_ = top->prev_;
}
bool StackGuard::CheckInterrupt(InterruptFlag flag) {
ExecutionAccess access(isolate_);
return thread_local_.interrupt_flags_ & flag;
}
void StackGuard::RequestInterrupt(InterruptFlag flag) {
ExecutionAccess access(isolate_);
// Check the chain of PostponeInterruptsScopes for interception.
if (thread_local_.postpone_interrupts_ &&
thread_local_.postpone_interrupts_->Intercept(flag)) {
return;
}
// Not intercepted. Set as active interrupt flag.
thread_local_.interrupt_flags_ |= flag;
set_interrupt_limits(access);
// If this isolate is waiting in a futex, notify it to wake up.
isolate_->futex_wait_list_node()->NotifyWake();
}
void StackGuard::ClearInterrupt(InterruptFlag flag) {
ExecutionAccess access(isolate_);
// Clear the interrupt flag from the chain of PostponeInterruptsScopes.
for (PostponeInterruptsScope* current = thread_local_.postpone_interrupts_;
current != NULL;
current = current->prev_) {
current->intercepted_flags_ &= ~flag;
}
// Clear the interrupt flag from the active interrupt flags.
thread_local_.interrupt_flags_ &= ~flag;
if (!has_pending_interrupts(access)) reset_limits(access);
}
bool StackGuard::CheckAndClearInterrupt(InterruptFlag flag) {
ExecutionAccess access(isolate_);
bool result = (thread_local_.interrupt_flags_ & flag);
thread_local_.interrupt_flags_ &= ~flag;
if (!has_pending_interrupts(access)) reset_limits(access);
return result;
}
char* StackGuard::ArchiveStackGuard(char* to) {
ExecutionAccess access(isolate_);
MemCopy(to, reinterpret_cast<char*>(&thread_local_), sizeof(ThreadLocal));
ThreadLocal blank;
// Set the stack limits using the old thread_local_.
// TODO(isolates): This was the old semantics of constructing a ThreadLocal
// (as the ctor called SetStackLimits, which looked at the
// current thread_local_ from StackGuard)-- but is this
// really what was intended?
isolate_->heap()->SetStackLimits();
thread_local_ = blank;
return to + sizeof(ThreadLocal);
}
char* StackGuard::RestoreStackGuard(char* from) {
ExecutionAccess access(isolate_);
MemCopy(reinterpret_cast<char*>(&thread_local_), from, sizeof(ThreadLocal));
isolate_->heap()->SetStackLimits();
return from + sizeof(ThreadLocal);
}
void StackGuard::FreeThreadResources() {
Isolate::PerIsolateThreadData* per_thread =
isolate_->FindOrAllocatePerThreadDataForThisThread();
per_thread->set_stack_limit(thread_local_.real_climit_);
}
void StackGuard::ThreadLocal::Clear() {
real_jslimit_ = kIllegalLimit;
set_jslimit(kIllegalLimit);
real_climit_ = kIllegalLimit;
set_climit(kIllegalLimit);
postpone_interrupts_ = NULL;
interrupt_flags_ = 0;
}
bool StackGuard::ThreadLocal::Initialize(Isolate* isolate) {
bool should_set_stack_limits = false;
if (real_climit_ == kIllegalLimit) {
const uintptr_t kLimitSize = FLAG_stack_size * KB;
DCHECK(GetCurrentStackPosition() > kLimitSize);
uintptr_t limit = GetCurrentStackPosition() - kLimitSize;
real_jslimit_ = SimulatorStack::JsLimitFromCLimit(isolate, limit);
set_jslimit(SimulatorStack::JsLimitFromCLimit(isolate, limit));
real_climit_ = limit;
set_climit(limit);
should_set_stack_limits = true;
}
postpone_interrupts_ = NULL;
interrupt_flags_ = 0;
return should_set_stack_limits;
}
void StackGuard::ClearThread(const ExecutionAccess& lock) {
thread_local_.Clear();
isolate_->heap()->SetStackLimits();
}
void StackGuard::InitThread(const ExecutionAccess& lock) {
if (thread_local_.Initialize(isolate_)) isolate_->heap()->SetStackLimits();
Isolate::PerIsolateThreadData* per_thread =
isolate_->FindOrAllocatePerThreadDataForThisThread();
uintptr_t stored_limit = per_thread->stack_limit();
// You should hold the ExecutionAccess lock when you call this.
if (stored_limit != 0) {
SetStackLimit(stored_limit);
}
}
// --- C a l l s t o n a t i v e s ---
void StackGuard::HandleGCInterrupt() {
if (CheckAndClearInterrupt(GC_REQUEST)) {
isolate_->heap()->HandleGCRequest();
}
}
Object* StackGuard::HandleInterrupts() {
if (FLAG_verify_predictable) {
// Advance synthetic time by making a time request.
isolate_->heap()->MonotonicallyIncreasingTimeInMs();
}
if (CheckAndClearInterrupt(GC_REQUEST)) {
isolate_->heap()->HandleGCRequest();
}
if (CheckDebugBreak() || CheckDebugCommand()) {
isolate_->debug()->HandleDebugBreak();
}
if (CheckAndClearInterrupt(TERMINATE_EXECUTION)) {
return isolate_->TerminateExecution();
}
if (CheckAndClearInterrupt(DEOPT_MARKED_ALLOCATION_SITES)) {
isolate_->heap()->DeoptMarkedAllocationSites();
}
if (CheckAndClearInterrupt(INSTALL_CODE)) {
DCHECK(isolate_->concurrent_recompilation_enabled());
isolate_->optimizing_compile_dispatcher()->InstallOptimizedFunctions();
}
if (CheckAndClearInterrupt(API_INTERRUPT)) {
// Callbacks must be invoked outside of ExecusionAccess lock.
isolate_->InvokeApiInterruptCallbacks();
}
isolate_->counters()->stack_interrupts()->Increment();
isolate_->counters()->runtime_profiler_ticks()->Increment();
isolate_->runtime_profiler()->MarkCandidatesForOptimization();
return isolate_->heap()->undefined_value();
}
} // namespace internal
} // namespace v8