Make sure we send fresh Sendports to other Isolates.

For now I prefer not to share *any* data between two different isolates.
We can relax this later.

Review URL: https://chromereviews.googleplex.com/3522014

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@33 260f80e4-7a28-3924-810f-c04153c831b5

compiler/lib/implementation/isolate.dart

@@ -93,6 +93,14 @@ class ReceivePortImpl implements ReceivePort {
   }
 
   SendPort toSendPort() {
+    return _toNewSendPort();
+  }
+
+  /**
+   * Returns a fresh [SendPort]. The implementation is not allowed to cache
+   * existing ports.
+   */
+  SendPort _toNewSendPort() {
     return new SendPortImpl(_currentWorkerId(), _currentIsolateId(), _id);
   }
 
@@ -122,24 +130,32 @@ class ReceivePortImpl implements ReceivePort {
 
 class ReceivePortSingleShotImpl implements ReceivePort {
 
-  ReceivePortSingleShotImpl() : port_ = new ReceivePortImpl() { }
+  ReceivePortSingleShotImpl() : _port = new ReceivePortImpl() { }
 
   void receive(void callback(var message, SendPort replyTo)) {
-    port_.receive((var message, SendPort replyTo) {
-      port_.close();
+    _port.receive((var message, SendPort replyTo) {
+      _port.close();
       callback(message, replyTo);
     });
   }
 
   void close() {
-    port_.close();
+    _port.close();
   }
 
   SendPort toSendPort() {
-    return port_.toSendPort();
+    return _toNewSendPort();
   }
 
-  final ReceivePortImpl port_;
+  /**
+   * Returns a fresh [SendPort]. The implementation is not allowed to cache
+   * existing ports.
+   */
+  SendPort _toNewSendPort() {
+    return _port._toNewSendPort();
+  }
+
+  final ReceivePortImpl _port;
 
 }
 

compiler/lib/implementation/isolate_serialization.dart

@@ -96,20 +96,17 @@ class Copier extends MessageTraverser {
   }
 
   SendPort visitSendPort(SendPortImpl port) {
-    // No need to copy the sendport.
-    return port;
+    return new SendPortImpl(port._workerId,
+                            port._isolateId,
+                            port._receivePortId);
   }
 
   SendPort visitReceivePort(ReceivePortImpl port) {
-    // TODO(floitsch): should we instead call toFreshSendPort? to be certain
-    // that objects are not shared.
-    return port.toSendPort();
+    return port._toNewSendPort();
   }
 
   SendPort visitReceivePortSingleShot(ReceivePortSingleShotImpl port) {
-    // TODO(floitsch): should we instead call toFreshSendPort? to be certain
-    // that objects are not shared.
-    return port.toSendPort();
+    return port._toNewSendPort();
   }
 }