Math.abs rewrited to not use Runtime.

test/mjsunit/abs.js

Index: test/mjsunit/abs.js
===================================================================
--- test/mjsunit/abs.js	(revision 0)
+++ test/mjsunit/abs.js	(revision 0)
@@ -0,0 +1,48 @@
+// 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.
+//     * 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.
+
+// Test Math.sin and Math.abs.
+
+assertEquals(1, Math.abs(1));  // Positive SMI.
+assertEquals(1, Math.abs(-1));  // Negative SMI.
+assertEquals(0.5, Math.abs(0.5));  // Positive double.
+assertEquals(0.5, Math.abs(-0.5));  // Negative double.
+assertEquals('Infinity', Math.abs(Number('+Infinity').toString()));
+assertEquals('Infinity', Math.abs(Number('-Infinity').toString()));
+assertEquals('NaN', Math.abs(NaN).toString());
+assertEquals('NaN', Math.abs(-NaN).toString());
+
+var minusZero = 1 / (-1 / 0);
+function isMinusZero(x) {
+  return x === 0 && 1 / x < 0;
+}
+
+assertTrue(!isMinusZero(0));
+assertTrue(isMinusZero(minusZero));
+assertEquals(0, Math.abs(minusZero));
+assertTrue(!isMinusZero(Math.abs(minusZero)));
+assertTrue(!isMinusZero(Math.abs(0.0)));