| /* s_tanf.c -- float version of s_tan.c. |
| * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
| * Optimized by Bruce D. Evans. |
| */ |
| |
| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| #include <sys/cdefs.h> |
| __FBSDID("$FreeBSD$"); |
| |
| #include <float.h> |
| |
| #include "math.h" |
| #define INLINE_KERNEL_TANDF |
| #define INLINE_REM_PIO2F |
| #include "math_private.h" |
| #include "e_rem_pio2f.c" |
| #include "k_tanf.c" |
| |
| /* Small multiples of pi/2 rounded to double precision. */ |
| static const double |
| t1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */ |
| t2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */ |
| t3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */ |
| t4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ |
| |
| float |
| tanf(float x) |
| { |
| double y; |
| int32_t n, hx, ix; |
| |
| GET_FLOAT_WORD(hx,x); |
| ix = hx & 0x7fffffff; |
| |
| if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */ |
| if(ix<0x39800000) /* |x| < 2**-12 */ |
| if(((int)x)==0) return x; /* x with inexact if x != 0 */ |
| return __kernel_tandf(x,1); |
| } |
| if(ix<=0x407b53d1) { /* |x| ~<= 5*pi/4 */ |
| if(ix<=0x4016cbe3) /* |x| ~<= 3pi/4 */ |
| return __kernel_tandf(x + (hx>0 ? -t1pio2 : t1pio2), -1); |
| else |
| return __kernel_tandf(x + (hx>0 ? -t2pio2 : t2pio2), 1); |
| } |
| if(ix<=0x40e231d5) { /* |x| ~<= 9*pi/4 */ |
| if(ix<=0x40afeddf) /* |x| ~<= 7*pi/4 */ |
| return __kernel_tandf(x + (hx>0 ? -t3pio2 : t3pio2), -1); |
| else |
| return __kernel_tandf(x + (hx>0 ? -t4pio2 : t4pio2), 1); |
| } |
| |
| /* tan(Inf or NaN) is NaN */ |
| else if (ix>=0x7f800000) return x-x; |
| |
| /* general argument reduction needed */ |
| else { |
| n = __ieee754_rem_pio2f(x,&y); |
| /* integer parameter: 1 -- n even; -1 -- n odd */ |
| return __kernel_tandf(y,1-((n&1)<<1)); |
| } |
| } |
