Improve and simplify removal of unreachable code

test/mjsunit/constant-branch-folding-liveness.js

 // Copyright 2013 the V8 project authors. All rights reserved.

[Jakob Kummerow, 2013/10/01 11:59:20]

You can drop this file; it is already present as
test/mjsunit/regress/regress-crbug-280333.js.

[danno, 2013/10/23 11:46:51]

Done.

 // 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
 //       with the distribution.
@@ skipping 26 matching lines @@
     return a;
   }
   return 0;
 }
 
 assertEquals(0, foo(1, funky));
 assertEquals(0, foo(1, funky));
 %OptimizeFunctionOnNextCall(foo);
 assertEquals(0, foo(1, funky));
 assertEquals(2, foo(1, function() { return true; }));