Revert "tighten invariants of HValue::InferRange"

test/mjsunit/math-round.js

-// Copyright 2011 the V8 project authors. All rights reserved.
+// 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
 //       with the distribution.
@@ skipping 25 matching lines @@
   %OptimizeFunctionOnNextCall(doRound);
   assertEquals(expect, doRound(input));
 }
 
 testRound(0, 0);
 testRound(-0, -0);
 testRound(Infinity, Infinity);
 testRound(-Infinity, -Infinity);
 testRound(NaN, NaN);
 
-// Regression test for a bug where a negative zero coming from Math.round
-// was not properly handled by other operations.
-function roundsum(i, n) {
-  var ret = Math.round(n);
-  while (--i > 0) {
-    ret += Math.round(n);
-  }
-  return ret;
-}
-assertEquals(-0, roundsum(1, -0));
-%OptimizeFunctionOnNextCall(roundsum);
-// The optimized function will deopt.  Run it with enough iterations to try
-// to optimize via OSR (triggering the bug).
-assertEquals(-0, roundsum(100000, -0));
-
 testRound(1, 0.5);
 testRound(1, 0.7);
 testRound(1, 1);
 testRound(1, 1.1);
 testRound(1, 1.49999);
 testRound(-0, -0.5);
 testRound(-1, -0.5000000000000001);
 testRound(-1, -0.7);
 testRound(-1, -1);
 testRound(-1, -1.1);
@@ skipping 91 matching lines @@
 testRound(-Math.pow(2,52)+1, -max_fraction);
 testRound(-min_nonfraction, -min_nonfraction);
 testRound(-max_non_infinite, -max_non_infinite);
 
 testRound(min_smi31, min_smi31 - 0.5);
 testRound(min_smi31 + 1, min_smi31 + 0.5);
 testRound(min_smi32, min_smi32 - 0.5);
 testRound(min_smi32 + 1, min_smi32 + 0.5);