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 #include <float.h> 19 20 #include "math.h" 21 #define INLINE_KERNEL_COSDF 22 #define INLINE_KERNEL_SINDF 23 #define INLINE_REM_PIO2F 24 #include "math_private.h" 25 #include "e_rem_pio2f.c" 26 #include "k_cosf.c" 27 #include "k_sinf.c" 28 29 /* Small multiples of pi/2 rounded to double precision. */ 30 static const double 31 s1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */ 32 s2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */ 33 s3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */ 34 s4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ 35 36 float 37 sinf(float x) 38 { 39 double y; 40 int32_t n, hx, ix; 41 42 GET_FLOAT_WORD(hx,x); 43 ix = hx & 0x7fffffff; 44 45 if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */ 46 if(ix<0x39800000) /* |x| < 2**-12 */ 47 if(((int)x)==0) return x; /* x with inexact if x != 0 */ 48 return __kernel_sindf(x); 49 } 50 if(ix<=0x407b53d1) { /* |x| ~<= 5*pi/4 */ 51 if(ix<=0x4016cbe3) { /* |x| ~<= 3pi/4 */ 52 if(hx>0) 53 return __kernel_cosdf(x - s1pio2); 54 else 55 return -__kernel_cosdf(x + s1pio2); 56 } else 57 return __kernel_sindf((hx > 0 ? s2pio2 : -s2pio2) - x); 58 } 59 if(ix<=0x40e231d5) { /* |x| ~<= 9*pi/4 */ 60 if(ix<=0x40afeddf) { /* |x| ~<= 7*pi/4 */ 61 if(hx>0) 62 return -__kernel_cosdf(x - s3pio2); 63 else 64 return __kernel_cosdf(x + s3pio2); 65 } else 66 return __kernel_sindf(x + (hx > 0 ? -s4pio2 : s4pio2)); 67 } 68 69 /* sin(Inf or NaN) is NaN */ 70 else if (ix>=0x7f800000) return x-x; 71 72 /* general argument reduction needed */ 73 else { 74 n = __ieee754_rem_pio2f(x,&y); 75 switch(n&3) { 76 case 0: return __kernel_sindf(y); 77 case 1: return __kernel_cosdf(y); 78 case 2: return __kernel_sindf(-y); 79 default: 80 return -__kernel_cosdf(y); 81 } 82 } 83 } 84