s_cosf.c revision 8870
12116Sjkh/* s_cosf.c -- float version of s_cos.c. 22116Sjkh * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 32116Sjkh */ 42116Sjkh 52116Sjkh/* 62116Sjkh * ==================================================== 72116Sjkh * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 82116Sjkh * 92116Sjkh * Developed at SunPro, a Sun Microsystems, Inc. business. 102116Sjkh * Permission to use, copy, modify, and distribute this 118870Srgrimes * software is freely granted, provided that this notice 122116Sjkh * is preserved. 132116Sjkh * ==================================================== 142116Sjkh */ 152116Sjkh 162116Sjkh#ifndef lint 178870Srgrimesstatic char rcsid[] = "$Id: s_cosf.c,v 1.1.1.1 1994/08/19 09:39:58 jkh Exp $"; 182116Sjkh#endif 192116Sjkh 202116Sjkh#include "math.h" 212116Sjkh#include "math_private.h" 222116Sjkh 232116Sjkh#ifdef __STDC__ 242116Sjkhstatic const float one=1.0; 252116Sjkh#else 262116Sjkhstatic float one=1.0; 272116Sjkh#endif 282116Sjkh 292116Sjkh#ifdef __STDC__ 302116Sjkh float cosf(float x) 312116Sjkh#else 322116Sjkh float cosf(x) 332116Sjkh float x; 342116Sjkh#endif 352116Sjkh{ 362116Sjkh float y[2],z=0.0; 372116Sjkh int32_t n,ix; 382116Sjkh 392116Sjkh GET_FLOAT_WORD(ix,x); 402116Sjkh 412116Sjkh /* |x| ~< pi/4 */ 422116Sjkh ix &= 0x7fffffff; 432116Sjkh if(ix <= 0x3f490fd8) return __kernel_cosf(x,z); 442116Sjkh 452116Sjkh /* cos(Inf or NaN) is NaN */ 462116Sjkh else if (ix>=0x7f800000) return x-x; 472116Sjkh 482116Sjkh /* argument reduction needed */ 492116Sjkh else { 502116Sjkh n = __ieee754_rem_pio2f(x,y); 512116Sjkh switch(n&3) { 522116Sjkh case 0: return __kernel_cosf(y[0],y[1]); 532116Sjkh case 1: return -__kernel_sinf(y[0],y[1],1); 542116Sjkh case 2: return -__kernel_cosf(y[0],y[1]); 552116Sjkh default: 562116Sjkh return __kernel_sinf(y[0],y[1],1); 572116Sjkh } 582116Sjkh } 592116Sjkh} 60