12aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm/* @(#)e_sinh.c 5.1 93/09/24 */ 22aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm/* 32aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * ==================================================== 42aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 52aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * 62aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * Developed at SunPro, a Sun Microsystems, Inc. business. 72aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * Permission to use, copy, modify, and distribute this 82aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * software is freely granted, provided that this notice 92aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * is preserved. 102aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * ==================================================== 112aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm */ 122aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm#include <LibConfig.h> 132aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm#include <sys/EfiCdefs.h> 142aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm#if defined(LIBM_SCCS) && !defined(lint) 152aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm__RCSID("$NetBSD: e_sinh.c,v 1.11 2002/05/26 22:01:52 wiz Exp $"); 162aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm#endif 172aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 182aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm#include "math.h" 192aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm#include "math_private.h" 202aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 212aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm/* __ieee754_sinh(x) 222aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * Method : 232aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * mathematically sinh(x) if defined to be (exp(x)-exp(-x))/2 242aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * 1. Replace x by |x| (sinh(-x) = -sinh(x)). 252aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * 2. 262aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * E + E/(E+1) 272aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * 0 <= x <= 22 : sinh(x) := --------------, E=expm1(x) 282aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * 2 292aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * 302aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * 22 <= x <= lnovft : sinh(x) := exp(x)/2 312aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * lnovft <= x <= ln2ovft: sinh(x) := exp(x/2)/2 * exp(x/2) 322aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * ln2ovft < x : sinh(x) := x*shuge (overflow) 332aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * 342aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * Special cases: 352aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * sinh(x) is |x| if x is +INF, -INF, or NaN. 362aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm * only sinh(0)=0 is exact for finite x. 372aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm */ 382aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 392aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylmstatic const double one = 1.0, shuge = 1.0e307; 402aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 412aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylmdouble 422aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm__ieee754_sinh(double x) 432aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm{ 442aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm double t,w,h; 452aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm int32_t ix,jx; 462aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm u_int32_t lx; 472aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 482aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm /* High word of |x|. */ 492aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm GET_HIGH_WORD(jx,x); 502aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm ix = jx&0x7fffffff; 512aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 522aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm /* x is INF or NaN */ 532aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm if(ix>=0x7ff00000) return x+x; 542aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 552aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm h = 0.5; 562aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm if (jx<0) h = -h; 572aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm /* |x| in [0,22], return sign(x)*0.5*(E+E/(E+1))) */ 582aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm if (ix < 0x40360000) { /* |x|<22 */ 592aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm if (ix<0x3e300000) /* |x|<2**-28 */ 602aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */ 612aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm t = expm1(fabs(x)); 622aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm if(ix<0x3ff00000) return h*(2.0*t-t*t/(t+one)); 632aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm return h*(t+t/(t+one)); 642aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm } 652aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 662aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */ 672aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm if (ix < 0x40862E42) return h*__ieee754_exp(fabs(x)); 682aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 692aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm /* |x| in [log(maxdouble), overflowthresold] */ 702aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm GET_LOW_WORD(lx,x); 712aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm if (ix<0x408633CE || ((ix==0x408633ce)&&(lx<=(u_int32_t)0x8fb9f87d))) { 722aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm w = __ieee754_exp(0.5*fabs(x)); 732aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm t = h*w; 742aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm return t*w; 752aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm } 762aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm 772aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm /* |x| > overflowthresold, sinh(x) overflow */ 782aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm return x*shuge; 792aa62f2bc9a9654687b377d9ca8a8c2c860a3852darylm} 80