1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/runtime/sharedRuntimeMath.hpp Thu May 22 11:36:23 2014 -0400
1.3 @@ -0,0 +1,97 @@
1.4 +/*
1.5 + * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#ifndef SHARE_VM_RUNTIME_SHAREDRUNTIMEMATH_HPP
1.29 +#define SHARE_VM_RUNTIME_SHAREDRUNTIMEMATH_HPP
1.30 +
1.31 +#include <math.h>
1.32 +
1.33 +// VM_LITTLE_ENDIAN is #defined appropriately in the Makefiles
1.34 +// [jk] this is not 100% correct because the float word order may different
1.35 +// from the byte order (e.g. on ARM FPA)
1.36 +#ifdef VM_LITTLE_ENDIAN
1.37 +# define __HI(x) *(1+(int*)&x)
1.38 +# define __LO(x) *(int*)&x
1.39 +#else
1.40 +# define __HI(x) *(int*)&x
1.41 +# define __LO(x) *(1+(int*)&x)
1.42 +#endif
1.43 +
1.44 +static double copysignA(double x, double y) {
1.45 + __HI(x) = (__HI(x)&0x7fffffff)|(__HI(y)&0x80000000);
1.46 + return x;
1.47 +}
1.48 +
1.49 +/*
1.50 + * ====================================================
1.51 + * Copyright (c) 1998 Oracle and/or its affiliates. All rights reserved.
1.52 + *
1.53 + * Developed at SunSoft, a Sun Microsystems, Inc. business.
1.54 + * Permission to use, copy, modify, and distribute this
1.55 + * software is freely granted, provided that this notice
1.56 + * is preserved.
1.57 + * ====================================================
1.58 + */
1.59 +
1.60 +/*
1.61 + * scalbn (double x, int n)
1.62 + * scalbn(x,n) returns x* 2**n computed by exponent
1.63 + * manipulation rather than by actually performing an
1.64 + * exponentiation or a multiplication.
1.65 + */
1.66 +
1.67 +static const double
1.68 +two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
1.69 +twom54 = 5.55111512312578270212e-17, /* 0x3C900000, 0x00000000 */
1.70 +hugeX = 1.0e+300,
1.71 +tiny = 1.0e-300;
1.72 +
1.73 +static double scalbnA (double x, int n) {
1.74 + int k,hx,lx;
1.75 + hx = __HI(x);
1.76 + lx = __LO(x);
1.77 + k = (hx&0x7ff00000)>>20; /* extract exponent */
1.78 + if (k==0) { /* 0 or subnormal x */
1.79 + if ((lx|(hx&0x7fffffff))==0) return x; /* +-0 */
1.80 + x *= two54;
1.81 + hx = __HI(x);
1.82 + k = ((hx&0x7ff00000)>>20) - 54;
1.83 + if (n< -50000) return tiny*x; /*underflow*/
1.84 + }
1.85 + if (k==0x7ff) return x+x; /* NaN or Inf */
1.86 + k = k+n;
1.87 + if (k > 0x7fe) return hugeX*copysignA(hugeX,x); /* overflow */
1.88 + if (k > 0) /* normal result */
1.89 + {__HI(x) = (hx&0x800fffff)|(k<<20); return x;}
1.90 + if (k <= -54) {
1.91 + if (n > 50000) /* in case integer overflow in n+k */
1.92 + return hugeX*copysignA(hugeX,x); /*overflow*/
1.93 + else return tiny*copysignA(tiny,x); /*underflow*/
1.94 + }
1.95 + k += 54; /* subnormal result */
1.96 + __HI(x) = (hx&0x800fffff)|(k<<20);
1.97 + return x*twom54;
1.98 +}
1.99 +
1.100 +#endif // SHARE_VM_RUNTIME_SHAREDRUNTIMEMATH_HPP
