s_sinf.c revision 176552
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 17176451Sdas#include <sys/cdefs.h> 18176451Sdas__FBSDID("$FreeBSD: head/lib/msun/src/s_sinf.c 176552 2008-02-25 13:33:20Z bde $"); 192116Sjkh 202116Sjkh#include "math.h" 21152869Sbde#define INLINE_KERNEL_COSDF 22152869Sbde#define INLINE_KERNEL_SINDF 232116Sjkh#include "math_private.h" 24152647Sbde#include "k_cosf.c" 25152647Sbde#include "k_sinf.c" 262116Sjkh 27152596Sbde/* Small multiples of pi/2 rounded to double precision. */ 28152596Sbdestatic const double 29152596Sbdes1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */ 30152596Sbdes2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */ 31152596Sbdes3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */ 32152596Sbdes4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ 33152596Sbde 3497413Salfredfloat 3597413Salfredsinf(float x) 362116Sjkh{ 37176552Sbde double y; 38152596Sbde int32_t n, hx, ix; 392116Sjkh 40152596Sbde GET_FLOAT_WORD(hx,x); 41152596Sbde ix = hx & 0x7fffffff; 422116Sjkh 43152540Sbde if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */ 44152540Sbde if(ix<0x39800000) /* |x| < 2**-12 */ 45152540Sbde if(((int)x)==0) return x; /* x with inexact if x != 0 */ 46152869Sbde return __kernel_sindf(x); 47151620Sbde } 48152871Sbde if(ix<=0x407b53d1) { /* |x| ~<= 5*pi/4 */ 49152871Sbde if(ix<=0x4016cbe3) { /* |x| ~<= 3pi/4 */ 50152596Sbde if(hx>0) 51152596Sbde return __kernel_cosdf(x - s1pio2); 52152596Sbde else 53152596Sbde return -__kernel_cosdf(x + s1pio2); 54152596Sbde } else 55152872Sbde return __kernel_sindf((hx > 0 ? s2pio2 : -s2pio2) - x); 56152596Sbde } 57152871Sbde if(ix<=0x40e231d5) { /* |x| ~<= 9*pi/4 */ 58152871Sbde if(ix<=0x40afeddf) { /* |x| ~<= 7*pi/4 */ 59152596Sbde if(hx>0) 60152596Sbde return -__kernel_cosdf(x - s3pio2); 61152596Sbde else 62152596Sbde return __kernel_cosdf(x + s3pio2); 63152596Sbde } else 64152596Sbde return __kernel_sindf(x + (hx > 0 ? -s4pio2 : s4pio2)); 65152596Sbde } 662116Sjkh 672116Sjkh /* sin(Inf or NaN) is NaN */ 682116Sjkh else if (ix>=0x7f800000) return x-x; 692116Sjkh 70152596Sbde /* general argument reduction needed */ 712116Sjkh else { 72176552Sbde n = __ieee754_rem_pio2f(x,&y); 732116Sjkh switch(n&3) { 74176552Sbde case 0: return __kernel_sindf(y); 75176552Sbde case 1: return __kernel_cosdf(y); 76176552Sbde case 2: return __kernel_sindf(-y); 772116Sjkh default: 78176552Sbde return -__kernel_cosdf(y); 792116Sjkh } 802116Sjkh } 812116Sjkh} 82