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authorIan Moffett <ian@osmora.org>2024-03-07 17:28:52 -0500
committerIan Moffett <ian@osmora.org>2024-03-07 18:24:51 -0500
commitf5e48e94a2f4d4bbd6e5628c7f2afafc6dbcc459 (patch)
tree93b156621dc0303816b37f60ba88051b702d92f6 /lib/mlibc/options/ansi/musl-generic-math/__cos.c
parentbd5969fc876a10b18613302db7087ef3c40f18e1 (diff)
build: Build mlibc + add distclean target
Signed-off-by: Ian Moffett <ian@osmora.org>
Diffstat (limited to 'lib/mlibc/options/ansi/musl-generic-math/__cos.c')
-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/__cos.c71
1 files changed, 0 insertions, 71 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/__cos.c b/lib/mlibc/options/ansi/musl-generic-math/__cos.c
deleted file mode 100644
index 46cefb3..0000000
--- a/lib/mlibc/options/ansi/musl-generic-math/__cos.c
+++ /dev/null
@@ -1,71 +0,0 @@
-/* origin: FreeBSD /usr/src/lib/msun/src/k_cos.c */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunSoft, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
-/*
- * __cos( x, y )
- * kernel cos function on [-pi/4, pi/4], pi/4 ~ 0.785398164
- * Input x is assumed to be bounded by ~pi/4 in magnitude.
- * Input y is the tail of x.
- *
- * Algorithm
- * 1. Since cos(-x) = cos(x), we need only to consider positive x.
- * 2. if x < 2^-27 (hx<0x3e400000 0), return 1 with inexact if x!=0.
- * 3. cos(x) is approximated by a polynomial of degree 14 on
- * [0,pi/4]
- * 4 14
- * cos(x) ~ 1 - x*x/2 + C1*x + ... + C6*x
- * where the remez error is
- *
- * | 2 4 6 8 10 12 14 | -58
- * |cos(x)-(1-.5*x +C1*x +C2*x +C3*x +C4*x +C5*x +C6*x )| <= 2
- * | |
- *
- * 4 6 8 10 12 14
- * 4. let r = C1*x +C2*x +C3*x +C4*x +C5*x +C6*x , then
- * cos(x) ~ 1 - x*x/2 + r
- * since cos(x+y) ~ cos(x) - sin(x)*y
- * ~ cos(x) - x*y,
- * a correction term is necessary in cos(x) and hence
- * cos(x+y) = 1 - (x*x/2 - (r - x*y))
- * For better accuracy, rearrange to
- * cos(x+y) ~ w + (tmp + (r-x*y))
- * where w = 1 - x*x/2 and tmp is a tiny correction term
- * (1 - x*x/2 == w + tmp exactly in infinite precision).
- * The exactness of w + tmp in infinite precision depends on w
- * and tmp having the same precision as x. If they have extra
- * precision due to compiler bugs, then the extra precision is
- * only good provided it is retained in all terms of the final
- * expression for cos(). Retention happens in all cases tested
- * under FreeBSD, so don't pessimize things by forcibly clipping
- * any extra precision in w.
- */
-
-#include "libm.h"
-
-static const double
-C1 = 4.16666666666666019037e-02, /* 0x3FA55555, 0x5555554C */
-C2 = -1.38888888888741095749e-03, /* 0xBF56C16C, 0x16C15177 */
-C3 = 2.48015872894767294178e-05, /* 0x3EFA01A0, 0x19CB1590 */
-C4 = -2.75573143513906633035e-07, /* 0xBE927E4F, 0x809C52AD */
-C5 = 2.08757232129817482790e-09, /* 0x3E21EE9E, 0xBDB4B1C4 */
-C6 = -1.13596475577881948265e-11; /* 0xBDA8FAE9, 0xBE8838D4 */
-
-double __cos(double x, double y)
-{
- double_t hz,z,r,w;
-
- z = x*x;
- w = z*z;
- r = z*(C1+z*(C2+z*C3)) + w*w*(C4+z*(C5+z*C6));
- hz = 0.5*z;
- w = 1.0-hz;
- return w + (((1.0-w)-hz) + (z*r-x*y));
-}