summaryrefslogtreecommitdiff
path: root/src/math/k_tanf.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/math/k_tanf.c')
-rw-r--r--src/math/k_tanf.c105
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);
- }
-}