58 lines
1.5 KiB
C
58 lines
1.5 KiB
C
/* e_sinhf.c -- float version of e_sinh.c.
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* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
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*/
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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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#include "cdefs-compat.h"
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//__FBSDID("$FreeBSD: src/lib/msun/src/e_sinhf.c,v 1.10 2011/10/21 06:28:47 das Exp $");
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#include <openlibm_math.h>
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#include "math_private.h"
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static const float one = 1.0, shuge = 1.0e37;
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OLM_DLLEXPORT float
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__ieee754_sinhf(float x)
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{
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float t,h;
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int32_t ix,jx;
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GET_FLOAT_WORD(jx,x);
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ix = jx&0x7fffffff;
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/* x is INF or NaN */
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if(ix>=0x7f800000) return x+x;
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h = 0.5;
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if (jx<0) h = -h;
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/* |x| in [0,9], return sign(x)*0.5*(E+E/(E+1))) */
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if (ix < 0x41100000) { /* |x|<9 */
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if (ix<0x39800000) /* |x|<2**-12 */
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if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */
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t = expm1f(fabsf(x));
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if(ix<0x3f800000) return h*((float)2.0*t-t*t/(t+one));
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return h*(t+t/(t+one));
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}
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/* |x| in [9, logf(maxfloat)] return 0.5*exp(|x|) */
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if (ix < 0x42b17217) return h*__ieee754_expf(fabsf(x));
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/* |x| in [logf(maxfloat), overflowthresold] */
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if (ix<=0x42b2d4fc)
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return h*2.0F*__ldexp_expf(fabsf(x), -1);
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/* |x| > overflowthresold, sinh(x) overflow */
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return x*shuge;
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}
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