s_sinf.c revision 152540
1/* s_sinf.c -- float version of s_sin.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#ifndef lint 17static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_sinf.c 152540 2005-11-17 03:53:22Z bde $"; 18#endif 19 20#include "math.h" 21#include "math_private.h" 22 23float 24sinf(float x) 25{ 26 float y[2]; 27 int32_t n, ix; 28 29 GET_FLOAT_WORD(ix,x); 30 ix &= 0x7fffffff; 31 32 if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */ 33 if(ix<0x39800000) /* |x| < 2**-12 */ 34 if(((int)x)==0) return x; /* x with inexact if x != 0 */ 35 return __kernel_sinf(x,0.0,0); 36 } 37 38 /* sin(Inf or NaN) is NaN */ 39 else if (ix>=0x7f800000) return x-x; 40 41 /* argument reduction needed */ 42 else { 43 n = __ieee754_rem_pio2f(x,y); 44 switch(n&3) { 45 case 0: return __kernel_sinf(y[0],y[1],1); 46 case 1: return __kernel_cosf(y[0],y[1]); 47 case 2: return -__kernel_sinf(y[0],y[1],1); 48 default: 49 return -__kernel_cosf(y[0],y[1]); 50 } 51 } 52} 53