11dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* e_coshf.c -- float version of e_cosh.c. 21dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 31dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 41dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 51dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* 61dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * ==================================================== 71dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 81dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 91dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Developed at SunPro, a Sun Microsystems, Inc. business. 101dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Permission to use, copy, modify, and distribute this 111dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * software is freely granted, provided that this notice 121dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * is preserved. 131dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * ==================================================== 141dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 151dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 16a0ee07829a9ba7e99ef68e8c12551301cc797f0fElliott Hughes#include <sys/cdefs.h> 17a0ee07829a9ba7e99ef68e8c12551301cc797f0fElliott Hughes__FBSDID("$FreeBSD$"); 181dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 191dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include "math.h" 201dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include "math_private.h" 211dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 221dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectstatic const float one = 1.0, half=0.5, huge = 1.0e30; 231dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 241dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectfloat 251dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project__ieee754_coshf(float x) 261dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 271dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project float t,w; 281dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project int32_t ix; 291dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 301dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project GET_FLOAT_WORD(ix,x); 311dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project ix &= 0x7fffffff; 321dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 331dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* x is INF or NaN */ 341dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if(ix>=0x7f800000) return x*x; 351dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 361dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* |x| in [0,0.5*ln2], return 1+expm1(|x|)^2/(2*exp(|x|)) */ 371dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if(ix<0x3eb17218) { 381dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project t = expm1f(fabsf(x)); 391dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project w = one+t; 401dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (ix<0x39800000) return one; /* cosh(tiny) = 1 */ 411dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return one+(t*t)/(w+w); 421dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 431dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 441dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* |x| in [0.5*ln2,9], return (exp(|x|)+1/exp(|x|))/2; */ 451dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (ix < 0x41100000) { 461dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project t = __ieee754_expf(fabsf(x)); 471dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return half*t+half/t; 481dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 491dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 501dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* |x| in [9, log(maxfloat)] return half*exp(|x|) */ 511dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (ix < 0x42b17217) return half*__ieee754_expf(fabsf(x)); 521dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 531dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* |x| in [log(maxfloat), overflowthresold] */ 54a0ee07829a9ba7e99ef68e8c12551301cc797f0fElliott Hughes if (ix<=0x42b2d4fc) 55a0ee07829a9ba7e99ef68e8c12551301cc797f0fElliott Hughes return __ldexp_expf(fabsf(x), -1); 561dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 571dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* |x| > overflowthresold, cosh(x) overflow */ 581dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return huge*huge; 591dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 60