tighten invariants of HValue::InferRange

test/mjsunit/math-round.js

Index: test/mjsunit/math-round.js
diff --git a/test/mjsunit/math-round.js b/test/mjsunit/math-round.js
index 1366557f6b8b3bbccf9b4d4a2156442706dba405..9fba720d4603e3a6c2edd69ddb88c2a9d3e8f996 100644
--- a/test/mjsunit/math-round.js
+++ b/test/mjsunit/math-round.js
@@ -1,4 +1,4 @@
-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright 2010, 2011 the V8 project authors. All rights reserved.

[Kevin Millikin (Chromium), 2011/08/02 10:24:14]

We just update the copyright date to 2011, not a range of dates.

 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -44,6 +44,22 @@ testRound(Infinity, Infinity);
 testRound(-Infinity, -Infinity);
 testRound(NaN, NaN);
 
+// Ensure that a negative zero coming from Math.round is properly
+// handled by other ops that take unboxed doubles.  See cr7514040.
+function roundsum(i,n) {
+  var ret = Math.round(n);
+  while (--i > 0) {
+    ret += Math.round(n);
+  }
+  return ret;
+}
+assertEquals(-0, roundsum(1000,-0));
+%OptimizeFunctionOnNextCall(roundsum);
+// It seems that %OptimizeFunctionOnNextCall doesn't always work!  Here
+// we push iterations up to a large number to ensure that we try to
+// unbox doubles as much as possible.
+assertEquals(-0, roundsum(1000000,-0));
+
 testRound(1, 0.5);
 testRound(1, 0.7);
 testRound(1, 1);