[Crankshaft] Don't do HMathFloorOfDiv optimization for kUint32 values

test/mjsunit/regress/regress-4507.js

Index: test/mjsunit/regress/regress-4507.js
diff --git a/test/mjsunit/regress/regress-4507.js b/test/mjsunit/regress/regress-4507.js
new file mode 100644
index 0000000000000000000000000000000000000000..a3fe5107be58e5a629635b5db90e4316f9ae7d3a
--- /dev/null
+++ b/test/mjsunit/regress/regress-4507.js
@@ -0,0 +1,19 @@
+// Copyright 2015 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 broken(value) {
+  return Math.floor(value/65536);
+}
+function toUnsigned(i) {
+  return i >>> 0;
+}
+function outer(i) {
+  return broken(toUnsigned(i));
+}
+for (var i = 0; i < 5; i++) outer(0);
+broken(0x80000000);  // Spice things up with a sprinkling of type feedback.
+%OptimizeFunctionOnNextCall(outer);
+assertEquals(32768, outer(0x80000000));