mirror of https://github.com/PrimeDecomp/prime.git
50 lines
1.1 KiB
C
50 lines
1.1 KiB
C
/* @(#)w_exp.c 1.2 95/01/04 */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunPro, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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/*
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* wrapper exp(x)
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*/
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#include "fdlibm.h"
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#ifdef __STDC__
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static const double
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#else
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static double
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#endif
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o_threshold = 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */
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u_threshold = -7.45133219101941108420e+02; /* 0xc0874910, 0xD52D3051 */
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#ifdef __STDC__
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double exp(double x) /* wrapper pow */
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#else
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double exp(x) /* wrapper exp */
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double x;
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#endif
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{
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#ifdef _IEEE_LIBM
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return __ieee754_exp(x);
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#else
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double z;
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z = __ieee754_exp(x);
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if (_LIB_VERSION == _IEEE_)
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return z;
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if (isfinite(x)) {
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if (x > o_threshold)
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return __kernel_standard(x, x, 6); /* exp overflow */
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else if (x < u_threshold)
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return __kernel_standard(x, x, 7); /* exp underflow */
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}
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return z;
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#endif
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}
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