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

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 bf590692073ebc62f6f4a34d9bc098316d7e9026..12a92657a1becac6f7049fe04dc01fef6b0580d6 100644
--- a/test/mjsunit/math-round.js
+++ b/test/mjsunit/math-round.js
@@ -38,6 +38,16 @@ function testRound(expect, input) {
   assertEquals(expect, doRound(input));
   %OptimizeFunctionOnNextCall(doRound);
   assertEquals(expect, doRound(input));
+
+  // Force the Math.round() representation to double to exercise the associated
+  // optimized code.
+  var doRoundToDouble = new Function('input',
+                                     '"' + (test_id++) + '";return Math.round(input) + -0.0');
+  assertEquals(expect, doRoundToDouble(input));
+  assertEquals(expect, doRoundToDouble(input));
+  assertEquals(expect, doRoundToDouble(input));
+  %OptimizeFunctionOnNextCall(doRoundToDouble);
+  assertEquals(expect, doRoundToDouble(input));
 }
 
 testRound(0, 0);