diff options
Diffstat (limited to 'lib/mlibc/options/ansi/musl-generic-math/erff.c')
| -rw-r--r-- | lib/mlibc/options/ansi/musl-generic-math/erff.c | 183 |
1 files changed, 0 insertions, 183 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/erff.c b/lib/mlibc/options/ansi/musl-generic-math/erff.c deleted file mode 100644 index ed5f397..0000000 --- a/lib/mlibc/options/ansi/musl-generic-math/erff.c +++ /dev/null @@ -1,183 +0,0 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/s_erff.c */ -/* - * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. - */ -/* - * ==================================================== - * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. - * - * Developed at SunPro, a Sun Microsystems, Inc. business. - * Permission to use, copy, modify, and distribute this - * software is freely granted, provided that this notice - * is preserved. - * ==================================================== - */ - -#include "libm.h" - -static const float -erx = 8.4506291151e-01, /* 0x3f58560b */ -/* - * Coefficients for approximation to erf on [0,0.84375] - */ -efx8 = 1.0270333290e+00, /* 0x3f8375d4 */ -pp0 = 1.2837916613e-01, /* 0x3e0375d4 */ -pp1 = -3.2504209876e-01, /* 0xbea66beb */ -pp2 = -2.8481749818e-02, /* 0xbce9528f */ -pp3 = -5.7702702470e-03, /* 0xbbbd1489 */ -pp4 = -2.3763017452e-05, /* 0xb7c756b1 */ -qq1 = 3.9791721106e-01, /* 0x3ecbbbce */ -qq2 = 6.5022252500e-02, /* 0x3d852a63 */ -qq3 = 5.0813062117e-03, /* 0x3ba68116 */ -qq4 = 1.3249473704e-04, /* 0x390aee49 */ -qq5 = -3.9602282413e-06, /* 0xb684e21a */ -/* - * Coefficients for approximation to erf in [0.84375,1.25] - */ -pa0 = -2.3621185683e-03, /* 0xbb1acdc6 */ -pa1 = 4.1485610604e-01, /* 0x3ed46805 */ -pa2 = -3.7220788002e-01, /* 0xbebe9208 */ -pa3 = 3.1834661961e-01, /* 0x3ea2fe54 */ -pa4 = -1.1089469492e-01, /* 0xbde31cc2 */ -pa5 = 3.5478305072e-02, /* 0x3d1151b3 */ -pa6 = -2.1663755178e-03, /* 0xbb0df9c0 */ -qa1 = 1.0642088205e-01, /* 0x3dd9f331 */ -qa2 = 5.4039794207e-01, /* 0x3f0a5785 */ -qa3 = 7.1828655899e-02, /* 0x3d931ae7 */ -qa4 = 1.2617121637e-01, /* 0x3e013307 */ -qa5 = 1.3637083583e-02, /* 0x3c5f6e13 */ -qa6 = 1.1984500103e-02, /* 0x3c445aa3 */ -/* - * Coefficients for approximation to erfc in [1.25,1/0.35] - */ -ra0 = -9.8649440333e-03, /* 0xbc21a093 */ -ra1 = -6.9385856390e-01, /* 0xbf31a0b7 */ -ra2 = -1.0558626175e+01, /* 0xc128f022 */ -ra3 = -6.2375331879e+01, /* 0xc2798057 */ -ra4 = -1.6239666748e+02, /* 0xc322658c */ -ra5 = -1.8460508728e+02, /* 0xc3389ae7 */ -ra6 = -8.1287437439e+01, /* 0xc2a2932b */ -ra7 = -9.8143291473e+00, /* 0xc11d077e */ -sa1 = 1.9651271820e+01, /* 0x419d35ce */ -sa2 = 1.3765776062e+02, /* 0x4309a863 */ -sa3 = 4.3456588745e+02, /* 0x43d9486f */ -sa4 = 6.4538726807e+02, /* 0x442158c9 */ -sa5 = 4.2900814819e+02, /* 0x43d6810b */ -sa6 = 1.0863500214e+02, /* 0x42d9451f */ -sa7 = 6.5702495575e+00, /* 0x40d23f7c */ -sa8 = -6.0424413532e-02, /* 0xbd777f97 */ -/* - * Coefficients for approximation to erfc in [1/.35,28] - */ -rb0 = -9.8649431020e-03, /* 0xbc21a092 */ -rb1 = -7.9928326607e-01, /* 0xbf4c9dd4 */ -rb2 = -1.7757955551e+01, /* 0xc18e104b */ -rb3 = -1.6063638306e+02, /* 0xc320a2ea */ -rb4 = -6.3756646729e+02, /* 0xc41f6441 */ -rb5 = -1.0250950928e+03, /* 0xc480230b */ -rb6 = -4.8351919556e+02, /* 0xc3f1c275 */ -sb1 = 3.0338060379e+01, /* 0x41f2b459 */ -sb2 = 3.2579251099e+02, /* 0x43a2e571 */ -sb3 = 1.5367296143e+03, /* 0x44c01759 */ -sb4 = 3.1998581543e+03, /* 0x4547fdbb */ -sb5 = 2.5530502930e+03, /* 0x451f90ce */ -sb6 = 4.7452853394e+02, /* 0x43ed43a7 */ -sb7 = -2.2440952301e+01; /* 0xc1b38712 */ - -static float erfc1(float x) -{ - float_t s,P,Q; - - s = fabsf(x) - 1; - P = pa0+s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6))))); - Q = 1+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6))))); - return 1 - erx - P/Q; -} - -static float erfc2(uint32_t ix, float x) -{ - float_t s,R,S; - float z; - - if (ix < 0x3fa00000) /* |x| < 1.25 */ - return erfc1(x); - - x = fabsf(x); - s = 1/(x*x); - if (ix < 0x4036db6d) { /* |x| < 1/0.35 */ - R = ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*( - ra5+s*(ra6+s*ra7)))))); - S = 1.0f+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*( - sa5+s*(sa6+s*(sa7+s*sa8))))))); - } else { /* |x| >= 1/0.35 */ - R = rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*( - rb5+s*rb6))))); - S = 1.0f+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*( - sb5+s*(sb6+s*sb7)))))); - } - GET_FLOAT_WORD(ix, x); - SET_FLOAT_WORD(z, ix&0xffffe000); - return expf(-z*z - 0.5625f) * expf((z-x)*(z+x) + R/S)/x; -} - -float erff(float x) -{ - float r,s,z,y; - uint32_t ix; - int sign; - - GET_FLOAT_WORD(ix, x); - sign = ix>>31; - ix &= 0x7fffffff; - if (ix >= 0x7f800000) { - /* erf(nan)=nan, erf(+-inf)=+-1 */ - return 1-2*sign + 1/x; - } - if (ix < 0x3f580000) { /* |x| < 0.84375 */ - if (ix < 0x31800000) { /* |x| < 2**-28 */ - /*avoid underflow */ - return 0.125f*(8*x + efx8*x); - } - z = x*x; - r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4))); - s = 1+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5)))); - y = r/s; - return x + x*y; - } - if (ix < 0x40c00000) /* |x| < 6 */ - y = 1 - erfc2(ix,x); - else - y = 1 - 0x1p-120f; - return sign ? -y : y; -} - -float erfcf(float x) -{ - float r,s,z,y; - uint32_t ix; - int sign; - - GET_FLOAT_WORD(ix, x); - sign = ix>>31; - ix &= 0x7fffffff; - if (ix >= 0x7f800000) { - /* erfc(nan)=nan, erfc(+-inf)=0,2 */ - return 2*sign + 1/x; - } - - if (ix < 0x3f580000) { /* |x| < 0.84375 */ - if (ix < 0x23800000) /* |x| < 2**-56 */ - return 1.0f - x; - z = x*x; - r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4))); - s = 1.0f+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5)))); - y = r/s; - if (sign || ix < 0x3e800000) /* x < 1/4 */ - return 1.0f - (x+x*y); - return 0.5f - (x - 0.5f + x*y); - } - if (ix < 0x41e00000) { /* |x| < 28 */ - return sign ? 2 - erfc2(ix,x) : erfc2(ix,x); - } - return sign ? 2 - 0x1p-120f : 0x1p-120f*0x1p-120f; -} |