[builtins] Introduce proper Float64Atan and Float64Atan2 operators.

src/js/math.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 (function(global, utils) {
 "use strict";
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
@@ skipping 11 matching lines @@
 var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
 
 //-------------------------------------------------------------------
 
 // ECMA 262 - 15.8.2.1
 function MathAbs(x) {
   x = +x;
   return (x > 0) ? x : 0 - x;
 }
 
-// ECMA 262 - 15.8.2.5
-// The naming of y and x matches the spec, as does the order in which
-// ToNumber (valueOf) is called.
-function MathAtan2JS(y, x) {
-  y = +y;
-  x = +x;
-  return %MathAtan2(y, x);
-}
-
 // ECMA 262 - 15.8.2.8
 function MathExp(x) {
   return %MathExpRT(TO_NUMBER(x));
 }
 
 // ECMA 262 - 15.8.2.13
 function MathPowJS(x, y) {
   return %_MathPow(TO_NUMBER(x), TO_NUMBER(y));
 }
 
@@ skipping 136 matching lines @@
   "SQRT1_2", 0.7071067811865476,
   "SQRT2", 1.4142135623730951
 ]);
 
 // Set up non-enumerable functions of the Math object and
 // set their names.
 utils.InstallFunctions(GlobalMath, DONT_ENUM, [
   "random", MathRandom,
   "abs", MathAbs,
   "exp", MathExp,
-  "atan2", MathAtan2JS,
   "pow", MathPowJS,
   "sign", MathSign,
   "asinh", MathAsinh,
   "acosh", MathAcosh,
   "atanh", MathAtanh,
   "hypot", MathHypot,
   "cbrt", MathCbrt
 ]);
 
 %SetForceInlineFlag(MathAbs);
-%SetForceInlineFlag(MathAtan2JS);
 %SetForceInlineFlag(MathRandom);
 %SetForceInlineFlag(MathSign);
 
 // -------------------------------------------------------------------
 // Exports
 
 utils.Export(function(to) {
   to.MathAbs = MathAbs;
   to.MathExp = MathExp;
   to.IntRandom = MathRandomRaw;
 });
 
 })