Also delete force representations that have no uses.

test/mjsunit/regress/regress-force-representation.js

Index: test/mjsunit/regress/regress-force-representation.js
diff --git a/test/mjsunit/regress/regress-force-representation.js b/test/mjsunit/regress/regress-force-representation.js
new file mode 100644
index 0000000000000000000000000000000000000000..8f6746b7f2c47a43f61b31b47574a908d78cf52c
--- /dev/null
+++ b/test/mjsunit/regress/regress-force-representation.js
@@ -0,0 +1,22 @@
+// Copyright 2014 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.
+
+// Flags: --allow-natives-syntax
+
+function optimize(crankshaft_test) {
+  crankshaft_test();
+  crankshaft_test();
+  %OptimizeFunctionOnNextCall(crankshaft_test);
+  crankshaft_test();
+}
+
+function f() {
+  var v1 = 0;
+  var v2 = -0;
+  var t = v2++;
+  v2++;
+  return Math.max(v2++, v1++);
+}
+
+optimize(f);