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

test/mjsunit/math-floor-part1.js

Index: test/mjsunit/math-floor-part1.js
diff --git a/test/mjsunit/math-floor-part1.js b/test/mjsunit/math-floor-part1.js
index b57b3e20dc8782e6e655f0ecd4a66b572b654018..a4fca7c6d1c2c14e9cf88bcc3b8e918e69d083f7 100644
--- a/test/mjsunit/math-floor-part1.js
+++ b/test/mjsunit/math-floor-part1.js
@@ -37,6 +37,15 @@ function testFloor(expect, 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() {