diff options
Diffstat (limited to 'src/math/k_tanf.c')
-rw-r--r-- | src/math/k_tanf.c | 105 |
1 files changed, 0 insertions, 105 deletions
diff --git a/src/math/k_tanf.c b/src/math/k_tanf.c deleted file mode 100644 index 99ede58c..00000000 --- a/src/math/k_tanf.c +++ /dev/null @@ -1,105 +0,0 @@ -/* k_tanf.c -- float version of k_tan.c - * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. - */ - -/* - * ==================================================== - * Copyright 2004 Sun Microsystems, Inc. All Rights Reserved. - * - * Permission to use, copy, modify, and distribute this - * software is freely granted, provided that this notice - * is preserved. - * ==================================================== - */ - -#include <math.h> -#include "math_private.h" -static const float -one = 1.0000000000e+00, /* 0x3f800000 */ -pio4 = 7.8539812565e-01, /* 0x3f490fda */ -pio4lo= 3.7748947079e-08, /* 0x33222168 */ -T[] = { - 3.3333334327e-01, /* 0x3eaaaaab */ - 1.3333334029e-01, /* 0x3e088889 */ - 5.3968254477e-02, /* 0x3d5d0dd1 */ - 2.1869488060e-02, /* 0x3cb327a4 */ - 8.8632395491e-03, /* 0x3c11371f */ - 3.5920790397e-03, /* 0x3b6b6916 */ - 1.4562094584e-03, /* 0x3abede48 */ - 5.8804126456e-04, /* 0x3a1a26c8 */ - 2.4646313977e-04, /* 0x398137b9 */ - 7.8179444245e-05, /* 0x38a3f445 */ - 7.1407252108e-05, /* 0x3895c07a */ - -1.8558637748e-05, /* 0xb79bae5f */ - 2.5907305826e-05, /* 0x37d95384 */ -}; - -float -__kernel_tanf(float x, float y, int iy) -{ - float z,r,v,w,s; - int32_t ix,hx; - GET_FLOAT_WORD(hx,x); - ix = hx&0x7fffffff; /* high word of |x| */ - if(ix<0x31800000) { /* x < 2**-28 */ - if ((int) x == 0) { /* generate inexact */ - if ((ix | (iy + 1)) == 0) - return one / fabsf(x); - else { - if (iy == 1) - return x; - else { /* compute -1 / (x+y) carefully */ - double a, t; - - z = w = x + y; - GET_FLOAT_WORD(ix, z); - SET_FLOAT_WORD(z, ix & 0xfffff000); - v = y - (z - x); - t = a = -one / w; - GET_FLOAT_WORD(ix, t); - SET_FLOAT_WORD(t, ix & 0xfffff000); - s = one + t * z; - return t + a * (s + t * v); - } - } - } - } - if(ix>=0x3f2ca140) { /* |x|>=0.6744 */ - if(hx<0) {x = -x; y = -y;} - z = pio4-x; - w = pio4lo-y; - x = z+w; y = 0.0; - } - z = x*x; - w = z*z; - /* Break x^5*(T[1]+x^2*T[2]+...) into - * x^5(T[1]+x^4*T[3]+...+x^20*T[11]) + - * x^5(x^2*(T[2]+x^4*T[4]+...+x^22*[T12])) - */ - r = T[1]+w*(T[3]+w*(T[5]+w*(T[7]+w*(T[9]+w*T[11])))); - v = z*(T[2]+w*(T[4]+w*(T[6]+w*(T[8]+w*(T[10]+w*T[12]))))); - s = z*x; - r = y + z*(s*(r+v)+y); - r += T[0]*s; - w = x+r; - if(ix>=0x3f2ca140) { - v = (float)iy; - return (float)(1-((hx>>30)&2))*(v-(float)2.0*(x-(w*w/(w+v)-r))); - } - if(iy==1) return w; - else { /* if allow error up to 2 ulp, - simply return -1.0/(x+r) here */ - /* compute -1.0/(x+r) accurately */ - float a,t; - int32_t i; - z = w; - GET_FLOAT_WORD(i,z); - SET_FLOAT_WORD(z,i&0xfffff000); - v = r-(z - x); /* z+v = r+x */ - t = a = -(float)1.0/w; /* a = -1.0/w */ - GET_FLOAT_WORD(i,t); - SET_FLOAT_WORD(t,i&0xfffff000); - s = (float)1.0+t*z; - return t+a*(s+t*v); - } -} |