diff options
Diffstat (limited to 'libm/src/k_tanf.c')
| -rw-r--r-- | libm/src/k_tanf.c | 67 |
1 files changed, 0 insertions, 67 deletions
diff --git a/libm/src/k_tanf.c b/libm/src/k_tanf.c deleted file mode 100644 index 6574030..0000000 --- a/libm/src/k_tanf.c +++ /dev/null @@ -1,67 +0,0 @@ -/* k_tanf.c -- float version of k_tan.c - * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. - * Optimized by Bruce D. Evans. - */ - -/* - * ==================================================== - * 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. - * ==================================================== - */ - -#ifndef INLINE_KERNEL_TANDF -#ifndef lint -static char rcsid[] = "$FreeBSD: src/lib/msun/src/k_tanf.c,v 1.20 2005/11/28 11:46:20 bde Exp $"; -#endif -#endif - -#include "math.h" -#include "math_private.h" - -/* |tan(x)/x - t(x)| < 2**-25.5 (~[-2e-08, 2e-08]). */ -static const double -T[] = { - 0x15554d3418c99f.0p-54, /* 0.333331395030791399758 */ - 0x1112fd38999f72.0p-55, /* 0.133392002712976742718 */ - 0x1b54c91d865afe.0p-57, /* 0.0533812378445670393523 */ - 0x191df3908c33ce.0p-58, /* 0.0245283181166547278873 */ - 0x185dadfcecf44e.0p-61, /* 0.00297435743359967304927 */ - 0x1362b9bf971bcd.0p-59, /* 0.00946564784943673166728 */ -}; - -#ifdef INLINE_KERNEL_TANDF -extern inline -#endif -float -__kernel_tandf(double x, int iy) -{ - double z,r,w,s,t,u; - - z = x*x; - /* - * Split up the polynomial into small independent terms to give - * opportunities for parallel evaluation. The chosen splitting is - * micro-optimized for Athlons (XP, X64). It costs 2 multiplications - * relative to Horner's method on sequential machines. - * - * We add the small terms from lowest degree up for efficiency on - * non-sequential machines (the lowest degree terms tend to be ready - * earlier). Apart from this, we don't care about order of - * operations, and don't need to to care since we have precision to - * spare. However, the chosen splitting is good for accuracy too, - * and would give results as accurate as Horner's method if the - * small terms were added from highest degree down. - */ - r = T[4]+z*T[5]; - t = T[2]+z*T[3]; - w = z*z; - s = z*x; - u = T[0]+z*T[1]; - r = (x+s*u)+(s*w)*(t+w*r); - if(iy==1) return r; - else return -1.0/r; -} |