Deoptimization tests for instance field increment optimization.

language/src/InstanceIncrDeoptTest.dart

Index: language/src/InstanceIncrDeoptTest.dart
===================================================================
--- language/src/InstanceIncrDeoptTest.dart	(revision 0)
+++ language/src/InstanceIncrDeoptTest.dart	(revision 0)
@@ -0,0 +1,54 @@
+// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Check correct deoptimization of instance field increment.
+
+
+main() {
+  var a = new A();
+  var aa = new A();
+  for (int i = 0; i < 2000; i++) {
+    a.Incr();
+    myIncr(aa);
+    conditionalIncr(false, a);
+  }
+  Expect.equals(2000, a.f);
+  Expect.equals(2000, aa.f);
+  a.f = 1.0;
+  // Deoptimize ++ part of instance increment.
+  a.Incr();
+  Expect.equals(2.0, a.f);
+  var b = new B();
+  // Deoptimize getfield part of instance increment.
+  myIncr(b);
+  Expect.equals(1.0, b.f);
+  // Deoptimize since no type feedback was collected.
+  var old = a.f;
+  conditionalIncr(true, a);
+  Expect.equals(old + 1, a.f);
+}
+
+myIncr(var a) {
+  a.f++;
+}
+
+conditionalIncr(var f, var a) {
+  if (f) {
+    a.f++;
+  }
+}
+
+class A {
+  A() : f = 0;
+  Incr() {
+    f++;
+  }
+  var f;
+}
+
+class B {
+  B() : f = 0;
+  var f;
+}
+