[builtins] Introduce proper Float64Exp operator.

src/third_party/fdlibm/fdlibm.js

 // The following is adapted from fdlibm (http://www.netlib.org/fdlibm),
 //
 // ====================================================
 // Copyright (C) 1993-2004 by Sun Microsystems, Inc. All rights reserved.
 //
 // Developed at SunSoft, a Sun Microsystems, Inc. business.
 // Permission to use, copy, modify, and distribute this
 // software is freely granted, provided that this notice
 // is preserved.
 // ====================================================
@@ skipping 13 matching lines @@
 "use strict";
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var GlobalFloat64Array = global.Float64Array;
 var GlobalMath = global.Math;
 var MathAbs;
-var MathExp;
 var NaN = %GetRootNaN();
 var rempio2result;
 
 utils.Import(function(from) {
   MathAbs = from.MathAbs;
-  MathExp = from.MathExp;
 });
 
 utils.CreateDoubleResultArray = function(global) {
   rempio2result = new GlobalFloat64Array(2);
 };
 
 // -------------------------------------------------------------------
 
 define INVPIO2 = 6.36619772367581382433e-01;
 define PIO2_1  = 1.57079632673412561417;
@@ skipping 576 matching lines @@
   // |x| in [0, 22]. return sign(x)*0.5*(E+E/(E+1))
   var ax = MathAbs(x);
   if (ax < 22) {
     // For |x| < 2^-28, sinh(x) = x
     if (ax < TWO_M28) return x;
     var t = MathExpm1(ax);
     if (ax < 1) return h * (2 * t - t * t / (t + 1));
     return h * (t + t / (t + 1));
   }
   // |x| in [22, log(maxdouble)], return 0.5 * exp(|x|)
-  if (ax < LOG_MAXD) return h * MathExp(ax);
+  if (ax < LOG_MAXD) return h * %math_exp(ax);
   // |x| in [log(maxdouble), overflowthreshold]
   // overflowthreshold = 710.4758600739426
   if (ax <= KSINH_OVERFLOW) {
-    var w = MathExp(0.5 * ax);
+    var w = %math_exp(0.5 * ax);
     var t = h * w;
     return t * w;
   }
   // |x| > overflowthreshold or is NaN.
   // Return Infinity of the appropriate sign or NaN.
   return x * INFINITY;
 }
 
 
 // ES6 draft 09-27-13, section 20.2.2.12.
@@ skipping 25 matching lines @@
   // |x| in [0,0.5*log2], return 1+expm1(|x|)^2/(2*exp(|x|))
   if (ix < 0x3fd62e43) {
     var t = MathExpm1(MathAbs(x));
     var w = 1 + t;
     // For |x| < 2^-55, cosh(x) = 1
     if (ix < 0x3c800000) return w;
     return 1 + (t * t) / (w + w);
   }
   // |x| in [0.5*log2, 22], return (exp(|x|)+1/exp(|x|)/2
   if (ix < 0x40360000) {
-    var t = MathExp(MathAbs(x));
+    var t = %math_exp(MathAbs(x));
     return 0.5 * t + 0.5 / t;
   }
   // |x| in [22, log(maxdouble)], return half*exp(|x|)
-  if (ix < 0x40862e42) return 0.5 * MathExp(MathAbs(x));
+  if (ix < 0x40862e42) return 0.5 * %math_exp(MathAbs(x));
   // |x| in [log(maxdouble), overflowthreshold]
   if (MathAbs(x) <= KCOSH_OVERFLOW) {
-    var w = MathExp(0.5 * MathAbs(x));
+    var w = %math_exp(0.5 * MathAbs(x));
     var t = 0.5 * w;
     return t * w;
   }
   if (NUMBER_IS_NAN(x)) return x;
   // |x| > overflowthreshold.
   return INFINITY;
 }
 
 // ES6 draft 09-27-13, section 20.2.2.33.
 // Math.tanh(x)
@@ skipping 61 matching lines @@
   "sinh", MathSinh,
   "cosh", MathCosh,
   "tanh", MathTanh,
   "expm1", MathExpm1
 ]);
 
 %SetForceInlineFlag(MathSin);
 %SetForceInlineFlag(MathCos);
 
 })