s_sinf.c revision 152872
12116Sjkh/* s_sinf.c -- float version of s_sin.c. 22116Sjkh * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 3152871Sbde * Optimized by Bruce D. Evans. 42116Sjkh */ 52116Sjkh 62116Sjkh/* 72116Sjkh * ==================================================== 82116Sjkh * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 92116Sjkh * 102116Sjkh * Developed at SunPro, a Sun Microsystems, Inc. business. 112116Sjkh * Permission to use, copy, modify, and distribute this 128870Srgrimes * software is freely granted, provided that this notice 132116Sjkh * is preserved. 142116Sjkh * ==================================================== 152116Sjkh */ 162116Sjkh 172116Sjkh#ifndef lint 1850476Speterstatic char rcsid[] = "$FreeBSD: head/lib/msun/src/s_sinf.c 152872 2005-11-28 06:15:10Z bde $"; 192116Sjkh#endif 202116Sjkh 212116Sjkh#include "math.h" 22152869Sbde#define INLINE_KERNEL_COSDF 23152869Sbde#define INLINE_KERNEL_SINDF 242116Sjkh#include "math_private.h" 25152647Sbde#include "k_cosf.c" 26152647Sbde#include "k_sinf.c" 272116Sjkh 28152596Sbde/* Small multiples of pi/2 rounded to double precision. */ 29152596Sbdestatic const double 30152596Sbdes1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */ 31152596Sbdes2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */ 32152596Sbdes3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */ 33152596Sbdes4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ 34152596Sbde 3597413Salfredfloat 3697413Salfredsinf(float x) 372116Sjkh{ 38152540Sbde float y[2]; 39152596Sbde int32_t n, hx, ix; 402116Sjkh 41152596Sbde GET_FLOAT_WORD(hx,x); 42152596Sbde ix = hx & 0x7fffffff; 432116Sjkh 44152540Sbde if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */ 45152540Sbde if(ix<0x39800000) /* |x| < 2**-12 */ 46152540Sbde if(((int)x)==0) return x; /* x with inexact if x != 0 */ 47152869Sbde return __kernel_sindf(x); 48151620Sbde } 49152871Sbde if(ix<=0x407b53d1) { /* |x| ~<= 5*pi/4 */ 50152871Sbde if(ix<=0x4016cbe3) { /* |x| ~<= 3pi/4 */ 51152596Sbde if(hx>0) 52152596Sbde return __kernel_cosdf(x - s1pio2); 53152596Sbde else 54152596Sbde return -__kernel_cosdf(x + s1pio2); 55152596Sbde } else 56152872Sbde return __kernel_sindf((hx > 0 ? s2pio2 : -s2pio2) - x); 57152596Sbde } 58152871Sbde if(ix<=0x40e231d5) { /* |x| ~<= 9*pi/4 */ 59152871Sbde if(ix<=0x40afeddf) { /* |x| ~<= 7*pi/4 */ 60152596Sbde if(hx>0) 61152596Sbde return -__kernel_cosdf(x - s3pio2); 62152596Sbde else 63152596Sbde return __kernel_cosdf(x + s3pio2); 64152596Sbde } else 65152596Sbde return __kernel_sindf(x + (hx > 0 ? -s4pio2 : s4pio2)); 66152596Sbde } 672116Sjkh 682116Sjkh /* sin(Inf or NaN) is NaN */ 692116Sjkh else if (ix>=0x7f800000) return x-x; 702116Sjkh 71152596Sbde /* general argument reduction needed */ 722116Sjkh else { 732116Sjkh n = __ieee754_rem_pio2f(x,y); 742116Sjkh switch(n&3) { 75152869Sbde case 0: return __kernel_sindf((double)y[0]+y[1]); 76152869Sbde case 1: return __kernel_cosdf((double)y[0]+y[1]); 77152872Sbde case 2: return __kernel_sindf(-(double)y[0]-y[1]); 782116Sjkh default: 79152869Sbde return -__kernel_cosdf((double)y[0]+y[1]); 802116Sjkh } 812116Sjkh } 822116Sjkh} 83