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 #if defined(LIBM_SCCS) && !defined(lint) 17 static char rcsid[] = "$NetBSD: s_cosf.c,v 1.4 1995/05/10 20:47:03 jtc Exp $"; 18 #endif 19 20 #include "math.h" 21 #include "math_private.h" 22 23 float 24 cosf(float x) 25 { 26 float y[2],z=0.0; 27 int32_t n,ix; 28 29 GET_FLOAT_WORD(ix,x); 30 31 /* |x| ~< pi/4 */ 32 ix &= 0x7fffffff; 33 if(ix <= 0x3f490fd8) return __kernel_cosf(x,z); 34 35 /* cos(Inf or NaN) is NaN */ 36 else if (ix>=0x7f800000) return x-x; 37 38 /* argument reduction needed */ 39 else { 40 n = __ieee754_rem_pio2f(x,y); 41 switch(n&3) { 42 case 0: return __kernel_cosf(y[0],y[1]); 43 case 1: return -__kernel_sinf(y[0],y[1],1); 44 case 2: return -__kernel_cosf(y[0],y[1]); 45 default: 46 return __kernel_sinf(y[0],y[1],1); 47 } 48 } 49 } 50