Fix bug when generating a fast smi loop....

test/mjsunit/compiler/loopcount.js

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 57 matching lines @@
 assertEquals(0x40000001, f7());
 
 
 function f8() {
   var i;
   for (i = 0x3ffffffd; i <= 0x3fffffff; i++) {}
   i++; i++;
   return i;
 }
 assertEquals(0x40000002, f8());
+
+
+function f9() {
+  var i;
+  for (i = 0; i < 42; i++) {
+    return 42;
+  }
+}
+assertEquals(42, f9());