1 /* s_sinf.c -- float version of s_sin.c. 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 3 * Optimized by Bruce D. Evans. 4 */ 5 6 /* 7 * ==================================================== 8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 9 * 10 * Developed at SunPro, a Sun Microsystems, Inc. business. 11 * Permission to use, copy, modify, and distribute this 12 * software is freely granted, provided that this notice 13 * is preserved. 14 * ==================================================== 15 */ 16 17 #include <sys/cdefs.h> 18 __FBSDID("$FreeBSD$"); 19 20 #include <float.h> 21 22 #include "math.h" 23 #define INLINE_KERNEL_COSDF 24 #define INLINE_KERNEL_SINDF 25 #define INLINE_REM_PIO2F 26 #include "math_private.h" 27 #include "e_rem_pio2f.c" 28 #include "k_cosf.c" 29 #include "k_sinf.c" 30 31 /* Small multiples of pi/2 rounded to double precision. */ 32 static const double 33 s1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */ 34 s2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */ 35 s3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */ 36 s4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ 37 38 float 39 sinf(float x) 40 { 41 double y; 42 int32_t n, hx, ix; 43 44 GET_FLOAT_WORD(hx,x); 45 ix = hx & 0x7fffffff; 46 47 if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */ 48 if(ix<0x39800000) /* |x| < 2**-12 */ 49 if(((int)x)==0) return x; /* x with inexact if x != 0 */ 50 return __kernel_sindf(x); 51 } 52 if(ix<=0x407b53d1) { /* |x| ~<= 5*pi/4 */ 53 if(ix<=0x4016cbe3) { /* |x| ~<= 3pi/4 */ 54 if(hx>0) 55 return __kernel_cosdf(x - s1pio2); 56 else 57 return -__kernel_cosdf(x + s1pio2); 58 } else 59 return __kernel_sindf((hx > 0 ? s2pio2 : -s2pio2) - x); 60 } 61 if(ix<=0x40e231d5) { /* |x| ~<= 9*pi/4 */ 62 if(ix<=0x40afeddf) { /* |x| ~<= 7*pi/4 */ 63 if(hx>0) 64 return -__kernel_cosdf(x - s3pio2); 65 else 66 return __kernel_cosdf(x + s3pio2); 67 } else 68 return __kernel_sindf(x + (hx > 0 ? -s4pio2 : s4pio2)); 69 } 70 71 /* sin(Inf or NaN) is NaN */ 72 else if (ix>=0x7f800000) return x-x; 73 74 /* general argument reduction needed */ 75 else { 76 n = __ieee754_rem_pio2f(x,&y); 77 switch(n&3) { 78 case 0: return __kernel_sindf(y); 79 case 1: return __kernel_cosdf(y); 80 case 2: return __kernel_sindf(-y); 81 default: 82 return -__kernel_cosdf(y); 83 } 84 } 85 } 86