Port fdlibm implementation for Math.cosh.

third_party/fdlibm/fdlibm.cc

 // The following is adapted from fdlibm (http://www.netlib.org/fdlibm).
 //
 // ====================================================
 // Copyright (C) 1993 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 61 matching lines @@
     1.818357216161805012e-01,     //          42
     1.531383769920937332e-01,     //          43
     1.479819860511658591e-01,     // LP7      44
     7.09782712893383973096e+02,   //          45  overflow threshold for expm1
     1.44269504088896338700e+00,   // 1/ln2    46
     -3.33333333333331316428e-02,  // Q1       47  coefficients for expm1
     1.58730158725481460165e-03,   //          48
     -7.93650757867487942473e-05,  //          49
     4.00821782732936239552e-06,   //          50
     -2.01099218183624371326e-07,  // Q5       51
-    710.4758600739439             //          52  overflow threshold for sinh
+    710.4758600739439             //          52  overflow threshold sinh, cosh
 };
 
 
 // Table of constants for 2/pi, 396 Hex digits (476 decimal) of 2/pi
 static const int two_over_pi[] = {
     0xA2F983, 0x6E4E44, 0x1529FC, 0x2757D1, 0xF534DD, 0xC0DB62, 0x95993C,
     0x439041, 0xFE5163, 0xABDEBB, 0xC561B7, 0x246E3A, 0x424DD2, 0xE00649,
     0x2EEA09, 0xD1921C, 0xFE1DEB, 0x1CB129, 0xA73EE8, 0x8235F5, 0x2EBB44,
     0x84E99C, 0x7026B4, 0x5F7E41, 0x3991D6, 0x398353, 0x39F49C, 0x845F8B,
     0xBDF928, 0x3B1FF8, 0x97FFDE, 0x05980F, 0xEF2F11, 0x8B5A0A, 0x6D1F6D,
@@ skipping 179 matching lines @@
   int n = __kernel_rem_pio2(tx, y, e0, nx);
   if (hx < 0) {
     y[0] = -y[0];
     y[1] = -y[1];
     return -n;
   }
   return n;
 }
 }
 }  // namespace v8::internal