diff options
author | Ian Moffett <ian@osmora.org> | 2024-03-07 17:28:52 -0500 |
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committer | Ian Moffett <ian@osmora.org> | 2024-03-07 18:24:51 -0500 |
commit | f5e48e94a2f4d4bbd6e5628c7f2afafc6dbcc459 (patch) | |
tree | 93b156621dc0303816b37f60ba88051b702d92f6 /lib/mlibc/options/ansi/musl-generic-math/acos.c | |
parent | bd5969fc876a10b18613302db7087ef3c40f18e1 (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/acos.c')
-rw-r--r-- | lib/mlibc/options/ansi/musl-generic-math/acos.c | 101 |
1 files changed, 0 insertions, 101 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/acos.c b/lib/mlibc/options/ansi/musl-generic-math/acos.c deleted file mode 100644 index ea9c87b..0000000 --- a/lib/mlibc/options/ansi/musl-generic-math/acos.c +++ /dev/null @@ -1,101 +0,0 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/e_acos.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. - * ==================================================== - */ -/* acos(x) - * Method : - * acos(x) = pi/2 - asin(x) - * acos(-x) = pi/2 + asin(x) - * For |x|<=0.5 - * acos(x) = pi/2 - (x + x*x^2*R(x^2)) (see asin.c) - * For x>0.5 - * acos(x) = pi/2 - (pi/2 - 2asin(sqrt((1-x)/2))) - * = 2asin(sqrt((1-x)/2)) - * = 2s + 2s*z*R(z) ...z=(1-x)/2, s=sqrt(z) - * = 2f + (2c + 2s*z*R(z)) - * where f=hi part of s, and c = (z-f*f)/(s+f) is the correction term - * for f so that f+c ~ sqrt(z). - * For x<-0.5 - * acos(x) = pi - 2asin(sqrt((1-|x|)/2)) - * = pi - 0.5*(s+s*z*R(z)), where z=(1-|x|)/2,s=sqrt(z) - * - * Special cases: - * if x is NaN, return x itself; - * if |x|>1, return NaN with invalid signal. - * - * Function needed: sqrt - */ - -#include "libm.h" - -static const double -pio2_hi = 1.57079632679489655800e+00, /* 0x3FF921FB, 0x54442D18 */ -pio2_lo = 6.12323399573676603587e-17, /* 0x3C91A626, 0x33145C07 */ -pS0 = 1.66666666666666657415e-01, /* 0x3FC55555, 0x55555555 */ -pS1 = -3.25565818622400915405e-01, /* 0xBFD4D612, 0x03EB6F7D */ -pS2 = 2.01212532134862925881e-01, /* 0x3FC9C155, 0x0E884455 */ -pS3 = -4.00555345006794114027e-02, /* 0xBFA48228, 0xB5688F3B */ -pS4 = 7.91534994289814532176e-04, /* 0x3F49EFE0, 0x7501B288 */ -pS5 = 3.47933107596021167570e-05, /* 0x3F023DE1, 0x0DFDF709 */ -qS1 = -2.40339491173441421878e+00, /* 0xC0033A27, 0x1C8A2D4B */ -qS2 = 2.02094576023350569471e+00, /* 0x40002AE5, 0x9C598AC8 */ -qS3 = -6.88283971605453293030e-01, /* 0xBFE6066C, 0x1B8D0159 */ -qS4 = 7.70381505559019352791e-02; /* 0x3FB3B8C5, 0xB12E9282 */ - -static double R(double z) -{ - double_t p, q; - p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*pS5))))); - q = 1.0+z*(qS1+z*(qS2+z*(qS3+z*qS4))); - return p/q; -} - -double acos(double x) -{ - double z,w,s,c,df; - uint32_t hx,ix; - - GET_HIGH_WORD(hx, x); - ix = hx & 0x7fffffff; - /* |x| >= 1 or nan */ - if (ix >= 0x3ff00000) { - uint32_t lx; - - GET_LOW_WORD(lx,x); - if ((ix-0x3ff00000 | lx) == 0) { - /* acos(1)=0, acos(-1)=pi */ - if (hx >> 31) - return 2*pio2_hi + 0x1p-120f; - return 0; - } - return 0/(x-x); - } - /* |x| < 0.5 */ - if (ix < 0x3fe00000) { - if (ix <= 0x3c600000) /* |x| < 2**-57 */ - return pio2_hi + 0x1p-120f; - return pio2_hi - (x - (pio2_lo-x*R(x*x))); - } - /* x < -0.5 */ - if (hx >> 31) { - z = (1.0+x)*0.5; - s = sqrt(z); - w = R(z)*s-pio2_lo; - return 2*(pio2_hi - (s+w)); - } - /* x > 0.5 */ - z = (1.0-x)*0.5; - s = sqrt(z); - df = s; - SET_LOW_WORD(df,0); - c = (z-df*df)/(s+df); - w = R(z)*s+c; - return 2*(df+w); -} |