Optimize the message queue for many active ports with few messages.

runtime/vm/message_test.cc

Index: runtime/vm/message_test.cc
diff --git a/runtime/vm/message_test.cc b/runtime/vm/message_test.cc
index f302a7b1e04b9860b1bbd63e189899036f201f22..e2bb6721caa508a7f6d608250bf8c84d26058170 100644
--- a/runtime/vm/message_test.cc
+++ b/runtime/vm/message_test.cc
@@ -73,7 +73,7 @@ TEST_CASE(MessageQueue_BasicOperations) {
 }
 
 
-TEST_CASE(MessageQueue_FlushAll) {
+TEST_CASE(MessageQueue_Clear) {
   MessageQueue queue;
   MessageQueueTestPeer queue_peer(&queue);
   Dart_Port port1 = 1;
@@ -93,84 +93,10 @@ TEST_CASE(MessageQueue_FlushAll) {
   queue.Enqueue(msg2);
 
   EXPECT(queue_peer.HasMessage());
-  queue.FlushAll();
+  queue.Clear();
   EXPECT(!queue_peer.HasMessage());
 
   // msg1 and msg2 already delete by FlushAll.
 }
 
-
-TEST_CASE(MessageQueue_Flush) {
-  MessageQueue queue;
-  MessageQueueTestPeer queue_peer(&queue);
-  Dart_Port port1 = 1;
-  Dart_Port port2 = 2;
-
-  const char* str1 = "msg1";
-  const char* str2 = "msg2";
-
-  // Add two messages on different ports.
-  Message* msg1 =
-      new Message(port1, 0, AllocMsg(str1), strlen(str1) + 1,
-                  Message::kNormalPriority);
-  queue.Enqueue(msg1);
-  Message* msg2 =
-      new Message(port2, 0, AllocMsg(str2), strlen(str2) + 1,
-                  Message::kNormalPriority);
-  queue.Enqueue(msg2);
-  EXPECT(queue_peer.HasMessage());
-
-  queue.Flush(port1);
-
-  // One message is left in the queue.
-  EXPECT(queue_peer.HasMessage());
-  Message* msg = queue.Dequeue();
-  EXPECT(msg != NULL);
-  EXPECT_STREQ(str2, reinterpret_cast<char*>(msg->data()));
-
-  EXPECT(!queue_peer.HasMessage());
-
-  // msg1 is already deleted by Flush.
-  delete msg2;
-}
-
-
-TEST_CASE(MessageQueue_Flush_MultipleMessages) {
-  MessageQueue queue;
-  MessageQueueTestPeer queue_peer(&queue);
-  Dart_Port port1 = 1;
-
-  const char* str1 = "msg1";
-  const char* str2 = "msg2";
-
-  Message* msg1 =
-      new Message(port1, 0, AllocMsg(str1), strlen(str1) + 1,
-                  Message::kNormalPriority);
-  queue.Enqueue(msg1);
-  Message* msg2 =
-      new Message(port1, 0, AllocMsg(str2), strlen(str2) + 1,
-                  Message::kNormalPriority);
-  queue.Enqueue(msg2);
-  EXPECT(queue_peer.HasMessage());
-
-  queue.Flush(port1);
-
-  // Queue is empty.
-  EXPECT(!queue_peer.HasMessage());
-  // msg1 and msg2 are already deleted by Flush.
-}
-
-
-TEST_CASE(MessageQueue_Flush_EmptyQueue) {
-  MessageQueue queue;
-  MessageQueueTestPeer queue_peer(&queue);
-  Dart_Port port1 = 1;
-
-  EXPECT(!queue_peer.HasMessage());
-  queue.Flush(port1);
-
-  // Queue is still empty.
-  EXPECT(!queue_peer.HasMessage());
-}
-
 }  // namespace dart