Completely remove InterruptableThreadState and Fix ThreadRegistry leak

runtime/vm/thread.cc

Index: runtime/vm/thread.cc
diff --git a/runtime/vm/thread.cc b/runtime/vm/thread.cc
index fdd3272e340ecf1029b9a87c5c067bbcd3b80440..260f59088ae169ec397713235d46287c90f0e43b 100644
--- a/runtime/vm/thread.cc
+++ b/runtime/vm/thread.cc
@@ -21,6 +21,24 @@ namespace dart {
 ThreadLocalKey Thread::thread_key_ = OSThread::kUnsetThreadLocalKey;
 
 
+// Remove |thread| from each isolate's thread registry.
+class ThreadPruner : public IsolateVisitor {
+ public:
+  explicit ThreadPruner(Thread* thread)
+      : thread_(thread) {
+    ASSERT(thread_ != NULL);
+  }
+
+  void VisitIsolate(Isolate* isolate) {
+    ThreadRegistry* registry = isolate->thread_registry();
+    ASSERT(registry != NULL);
+    registry->PruneThread(thread_);
+  }
+ private:
+  Thread* thread_;
+};
+
+
 static void DeleteThread(void* thread) {
   delete reinterpret_cast<Thread*>(thread);
 }
@@ -29,6 +47,9 @@ static void DeleteThread(void* thread) {
 Thread::~Thread() {
   // We should cleanly exit any isolate before destruction.
   ASSERT(isolate_ == NULL);
+  // Clear |this| from all isolate's thread registry.
+  ThreadPruner pruner(this);
+  Isolate::VisitIsolates(&pruner);
 }
 
 
@@ -37,8 +58,11 @@ void Thread::InitOnceBeforeIsolate() {
   thread_key_ = OSThread::CreateThreadLocal(DeleteThread);
   ASSERT(thread_key_ != OSThread::kUnsetThreadLocalKey);
   ASSERT(Thread::Current() == NULL);
-  // Postpone initialization of VM constants for this first thread.
-  SetCurrent(new Thread(false));
+  // Allocate a new Thread and postpone initialization of VM constants for
+  // this first thread.
+  Thread* thread = new Thread(false);
+  // Verify that current thread was set.
+  ASSERT(Thread::Current() == thread);
 }
 
 
@@ -57,7 +81,10 @@ void Thread::SetCurrent(Thread* current) {
 
 void Thread::EnsureInit() {
   if (Thread::Current() == NULL) {
-    SetCurrent(new Thread());
+    // Allocate a new Thread.
+    Thread* thread = new Thread();
+    // Verify that current thread was set.
+    ASSERT(Thread::Current() == thread);
   }
 }
 
@@ -74,7 +101,8 @@ void Thread::CleanUp() {
 
 
 Thread::Thread(bool init_vm_constants)
-    : isolate_(NULL),
+    : id_(OSThread::GetCurrentThreadId()),
+      isolate_(NULL),
       store_buffer_block_(NULL) {
   ClearState();
 #define DEFAULT_INIT(type_name, member_name, init_expr, default_init_value)    \
@@ -84,6 +112,7 @@ CACHED_CONSTANTS_LIST(DEFAULT_INIT)
   if (init_vm_constants) {
     InitVMConstants();
   }
+  SetCurrent(this);
 }
 
 
@@ -131,15 +160,6 @@ void Thread::EnterIsolate(Isolate* isolate) {
   ASSERT(isolate->heap() != NULL);
   thread->heap_ = isolate->heap();
   thread->Schedule(isolate);
-  ASSERT(thread->thread_state() == NULL);
-  InterruptableThreadState* thread_state =
-      ThreadInterrupter::GetCurrentThreadState();
-#if defined(DEBUG)
-  thread->set_thread_state(NULL);  // Exclude thread itself from the dupe check.
-  Isolate::CheckForDuplicateThreadState(thread_state);
-  thread->set_thread_state(thread_state);
-#endif
-  ASSERT(thread_state != NULL);
   // TODO(koda): Migrate profiler interface to use Thread.
   Profiler::BeginExecution(isolate);
 }
@@ -151,7 +171,6 @@ void Thread::ExitIsolate() {
   if (thread == NULL || thread->isolate() == NULL) return;
   Isolate* isolate = thread->isolate();
   Profiler::EndExecution(isolate);
-  thread->set_thread_state(NULL);
   thread->Unschedule();
   // TODO(koda): Move store_buffer_block_ into State.
   thread->StoreBufferRelease();
@@ -259,6 +278,32 @@ void Thread::set_cha(CHA* value) {
 }
 
 
+void Thread::SetThreadInterrupter(ThreadInterruptCallback callback,
+                                  void* data) {
+  ASSERT(Thread::Current() == this);
+  thread_interrupt_callback_ = callback;
+  thread_interrupt_data_ = data;
+}
+
+
+bool Thread::IsThreadInterrupterEnabled(ThreadInterruptCallback* callback,
+                                        void** data) const {
+#if defined(TARGET_OS_WINDOWS)
+  // On Windows we expect this to be called from the thread interrupter thread.
+  ASSERT(id() != OSThread::GetCurrentThreadId());
+#else
+  // On posix platforms, we expect this to be called from signal handler.
+  ASSERT(id() == OSThread::GetCurrentThreadId());
+#endif
+  ASSERT(callback != NULL);
+  ASSERT(data != NULL);
+  *callback = thread_interrupt_callback_;
+  *data = thread_interrupt_data_;
+  return (*callback != NULL) &&
+         (*data != NULL);
+}
+
+
 bool Thread::CanLoadFromThread(const Object& object) {
 #define CHECK_OBJECT(type_name, member_name, expr, default_init_value)         \
   if (object.raw() == expr) return true;