Move promises recorded for debugging to thread local data.

src/debug.cc

 // Copyright 2012 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 "v8.h"
 
 #include "api.h"
 #include "arguments.h"
 #include "bootstrapper.h"
 #include "code-stubs.h"
@@ skipping 19 matching lines @@
 namespace v8 {
 namespace internal {
 
 Debug::Debug(Isolate* isolate)
     : has_break_points_(false),
       script_cache_(NULL),
       debug_info_list_(NULL),
       disable_break_(false),
       break_on_exception_(false),
       break_on_uncaught_exception_(false),
-      promise_catch_handlers_(0),
-      promise_getters_(0),
       isolate_(isolate) {
   ThreadInit();
 }
 
 
 static v8::Handle<v8::Context> GetDebugEventContext(Isolate* isolate) {
   Handle<Context> context = isolate->debug()->debugger_entry()->GetContext();
   // Isolate::context() may have been NULL when "script collected" event
   // occured.
   if (context.is_null()) return v8::Local<v8::Context>();
@@ skipping 452 matching lines @@
   thread_local_.step_count_ = 0;
   thread_local_.last_fp_ = 0;
   thread_local_.queued_step_count_ = 0;
   thread_local_.step_into_fp_ = 0;
   thread_local_.step_out_fp_ = 0;
   thread_local_.after_break_target_ = 0;
   // TODO(isolates): frames_are_dropped_?
   thread_local_.debugger_entry_ = NULL;
   thread_local_.has_pending_interrupt_ = false;
   thread_local_.restarter_frame_function_pointer_ = NULL;
+  thread_local_.promise_on_stack_ = NULL;
 }
 
 
 char* Debug::ArchiveDebug(char* storage) {
   char* to = storage;
   OS::MemCopy(to, reinterpret_cast<char*>(&thread_local_), sizeof(ThreadLocal));
   ThreadInit();
   return storage + ArchiveSpacePerThread();
 }
 
@@ skipping 718 matching lines @@
 
 bool Debug::IsBreakOnException(ExceptionBreakType type) {
   if (type == BreakUncaughtException) {
     return break_on_uncaught_exception_;
   } else {
     return break_on_exception_;
   }
 }
 
 
+Debug::PromiseOnStack::PromiseOnStack(Isolate* isolate,
+                                      PromiseOnStack* prev,
+                                      Handle<JSFunction> getter)
+    : isolate_(isolate), prev_(prev) {
+  handler_ = StackHandler::FromAddress(
+      Isolate::handler(isolate->thread_local_top()));
+  getter_ = Handle<JSFunction>::cast(
+      isolate->global_handles()->Create(*getter));
+}
+
+
+Debug::PromiseOnStack::~PromiseOnStack() {
+  isolate_->global_handles()->Destroy(Handle<Object>::cast(getter_).location());
+}
+
+
 void Debug::PromiseHandlePrologue(Handle<JSFunction> promise_getter) {
-  Handle<JSFunction> promise_getter_global = Handle<JSFunction>::cast(
-      isolate_->global_handles()->Create(*promise_getter));
-  StackHandler* handler =
-      StackHandler::FromAddress(Isolate::handler(isolate_->thread_local_top()));
-  promise_getters_.Add(promise_getter_global);
-  promise_catch_handlers_.Add(handler);
+  PromiseOnStack* prev = thread_local_.promise_on_stack_;
+  thread_local_.promise_on_stack_ =
+      new PromiseOnStack(isolate_, prev, promise_getter);
 }
 
 
 void Debug::PromiseHandleEpilogue() {
-  if (promise_catch_handlers_.length() == 0) return;
-  promise_catch_handlers_.RemoveLast();
-  Handle<Object> promise_getter = promise_getters_.RemoveLast();
-  isolate_->global_handles()->Destroy(promise_getter.location());
+  if (thread_local_.promise_on_stack_ == NULL) return;
+  PromiseOnStack* prev = thread_local_.promise_on_stack_->prev();
+  delete thread_local_.promise_on_stack_;
+  thread_local_.promise_on_stack_ = prev;
 }
 
 
 Handle<Object> Debug::GetPromiseForUncaughtException() {
   Handle<Object> undefined = isolate_->factory()->undefined_value();
-  if (promise_getters_.length() == 0) return undefined;
-  Handle<JSFunction> promise_getter = promise_getters_.last();
-  StackHandler* promise_catch = promise_catch_handlers_.last();
+  if (thread_local_.promise_on_stack_ == NULL) return undefined;
+  Handle<JSFunction> promise_getter = thread_local_.promise_on_stack_->getter();
+  StackHandler* promise_catch = thread_local_.promise_on_stack_->handler();
   // Find the top-most try-catch handler.
   StackHandler* handler = StackHandler::FromAddress(
       Isolate::handler(isolate_->thread_local_top()));
   while (handler != NULL && !handler->is_catch()) {
     handler = handler->next();
   }
 #ifdef DEBUG
   // Make sure that our promise catch handler is in the list of handlers,
   // even if it's not the top-most try-catch handler.
   StackHandler* temp = handler;
@@ skipping 2254 matching lines @@
   logger_->DebugEvent("Put", message.text());
 }
 
 
 void LockingCommandMessageQueue::Clear() {
   LockGuard<Mutex> lock_guard(&mutex_);
   queue_.Clear();
 }
 
 } }  // namespace v8::internal