ARM64: Generate optimized code for Math.floor and Math.round with double outputs.

test/mjsunit/math-floor-part1.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
@@ skipping 19 matching lines @@
 var test_id = 0;
 
 function testFloor(expect, input) {
   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));
+
+  var test_double_output = new Function(
+      'n',
+      '"' + (test_id++) + '";return Math.floor(n) + -0.0');
+  assertEquals(expect, test_double_output(input));
+  assertEquals(expect, test_double_output(input));
+  assertEquals(expect, test_double_output(input));
+  %OptimizeFunctionOnNextCall(test_double_output);
+  assertEquals(expect, test_double_output(input));
 }
 
 function zero() {
   var x = 0.5;
   return (function() { return x - 0.5; })();
 }
 
 function test() {
   // Ensure that a negative zero coming from Math.floor is properly handled
   // by other operations.
@@ skipping 34 matching lines @@
   testFloor(Infinity, Infinity);
   testFloor(-Infinity, -Infinity);
 }
 
 
 // Test in a loop to cover the custom IC and GC-related issues.
 for (var i = 0; i < 10; i++) {
   test();
   new Array(i * 10000);
 }