1 /* s_cosf.c -- float version of s_cos.c. 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 3 */ 4 5 /* 6 * ==================================================== 7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 8 * 9 * Developed at SunPro, a Sun Microsystems, Inc. business. 10 * Permission to use, copy, modify, and distribute this 11 * software is freely granted, provided that this notice 12 * is preserved. 13 * ==================================================== 14 */ 15 16 #include <sys/cdefs.h> 17 #if defined(LIBM_SCCS) && !defined(lint) 18 __RCSID("$NetBSD: s_cosf.c,v 1.9 2007/08/20 16:01:39 drochner Exp $"); 19 #endif 20 21 #include "namespace.h" 22 #include "math.h" 23 #include "math_private.h" 24 25 #if 0 /* notyet */ 26 #ifdef __weak_alias 27 __weak_alias(cosf, _cosf) 28 #endif 29 #endif 30 31 #if 0 32 static const float one=1.0; 33 #endif 34 35 float 36 cosf(float x) 37 { 38 float y[2],z=0.0; 39 int32_t n,ix; 40 41 GET_FLOAT_WORD(ix,x); 42 43 /* |x| ~< pi/4 */ 44 ix &= 0x7fffffff; 45 if(ix <= 0x3f490fd8) return __kernel_cosf(x,z); 46 47 /* cos(Inf or NaN) is NaN */ 48 else if (ix>=0x7f800000) return x-x; 49 50 /* argument reduction needed */ 51 else { 52 n = __ieee754_rem_pio2f(x,y); 53 switch(n&3) { 54 case 0: return __kernel_cosf(y[0],y[1]); 55 case 1: return -__kernel_sinf(y[0],y[1],1); 56 case 2: return -__kernel_cosf(y[0],y[1]); 57 default: 58 return __kernel_sinf(y[0],y[1],1); 59 } 60 } 61 } 62