Version 3.5.5.

test/mjsunit/math-floor.js

 // Copyright 2011 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.
 //     * Neither the name of Google Inc. nor the names of its
 //       contributors may be used to endorse or promote products derived
 //       from this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // Flags: --max-new-space-size=256 --allow-natives-syntax
 
+var test_id = 0;
+
 function testFloor(expect, input) {
-  function test(n) {
-    return Math.floor(n);
-  }
+  var test = new Function('n',
+                          '"' + (test_id++) + '";return Math.floor(n)');
   assertEquals(expect, test(input));
   assertEquals(expect, test(input));
   assertEquals(expect, test(input));
   %OptimizeFunctionOnNextCall(test);
   assertEquals(expect, test(input));
 }
 
 function zero() {
   var x = 0.5;
   return (function() { return x - 0.5; })();
 }
 
 function test() {
   testFloor(0, 0);
   testFloor(0, zero());
   testFloor(-0, -0);
   testFloor(Infinity, Infinity);
   testFloor(-Infinity, -Infinity);
   testFloor(NaN, NaN);
 
+  // Ensure that a negative zero coming from Math.floor is properly handled
+  // by other operations.
+  function ifloor(x) {
+    return 1 / Math.floor(x);
+  }
+  assertEquals(-Infinity, ifloor(-0));
+  assertEquals(-Infinity, ifloor(-0));
+  assertEquals(-Infinity, ifloor(-0));
+  %OptimizeFunctionOnNextCall(ifloor);
+  assertEquals(-Infinity, ifloor(-0));
+
   testFloor(0, 0.1);
   testFloor(0, 0.49999999999999994);
   testFloor(0, 0.5);
   testFloor(0, 0.7);
   testFloor(-1, -0.1);
   testFloor(-1, -0.49999999999999994);
   testFloor(-1, -0.5);
   testFloor(-1, -0.7);
   testFloor(1, 1);
   testFloor(1, 1.1);
@@ skipping 58 matching lines @@
   testFloor(-two_52 + 1, -two_52 + 1 + 0.1);
   testFloor(-two_52 + 1, -two_52 + 1 + 0.5);
   testFloor(-two_52 + 1, -two_52 + 1 + 0.7);
 }
 
 
 // Test in a loop to cover the custom IC and GC-related issues.
 for (var i = 0; i < 500; i++) {
   test();
 }
+
+
+// Regression test for a bug where a negative zero coming from Math.floor
+// was not properly handled by other operations.
+function floorsum(i, n) {
+  var ret = Math.floor(n);
+  while (--i > 0) {
+    ret += Math.floor(n);
+  }
+  return ret;
+}
+assertEquals(-0, floorsum(1, -0));
+%OptimizeFunctionOnNextCall(floorsum);
+// The optimized function will deopt.  Run it with enough iterations to try
+// to optimize via OSR (triggering the bug).
+assertEquals(-0, floorsum(100000, -0));