diff options
43 files changed, 3743 insertions, 0 deletions
diff --git a/lib/libm_dbl/README b/lib/libm_dbl/README new file mode 100644 index 0000000000..512b328261 --- /dev/null +++ b/lib/libm_dbl/README @@ -0,0 +1,32 @@ +This directory contains source code for the standard double-precision math +functions. + +The files lgamma.c, log10.c and tanh.c are too small to have a meaningful +copyright or license. + +The rest of the files in this directory are copied from the musl library, +v1.1.16, and, unless otherwise stated in the individual file, have the +following copyright and MIT license: + +---------------------------------------------------------------------- +Copyright © 2005-2014 Rich Felker, et al. + +Permission is hereby granted, free of charge, to any person obtaining +a copy of this software and associated documentation files (the +"Software"), to deal in the Software without restriction, including +without limitation the rights to use, copy, modify, merge, publish, +distribute, sublicense, and/or sell copies of the Software, and to +permit persons to whom the Software is furnished to do so, subject to +the following conditions: + +The above copyright notice and this permission notice shall be +included in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. +IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, +TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE +SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +---------------------------------------------------------------------- diff --git a/lib/libm_dbl/__cos.c b/lib/libm_dbl/__cos.c new file mode 100644 index 0000000000..46cefb3813 --- /dev/null +++ b/lib/libm_dbl/__cos.c @@ -0,0 +1,71 @@ +/* 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)); +} diff --git a/lib/libm_dbl/__expo2.c b/lib/libm_dbl/__expo2.c new file mode 100644 index 0000000000..740ac680e8 --- /dev/null +++ b/lib/libm_dbl/__expo2.c @@ -0,0 +1,16 @@ +#include "libm.h" + +/* k is such that k*ln2 has minimal relative error and x - kln2 > log(DBL_MIN) */ +static const int k = 2043; +static const double kln2 = 0x1.62066151add8bp+10; + +/* exp(x)/2 for x >= log(DBL_MAX), slightly better than 0.5*exp(x/2)*exp(x/2) */ +double __expo2(double x) +{ + double scale; + + /* note that k is odd and scale*scale overflows */ + INSERT_WORDS(scale, (uint32_t)(0x3ff + k/2) << 20, 0); + /* exp(x - k ln2) * 2**(k-1) */ + return exp(x - kln2) * scale * scale; +} diff --git a/lib/libm_dbl/__fpclassify.c b/lib/libm_dbl/__fpclassify.c new file mode 100644 index 0000000000..5c908ba3d2 --- /dev/null +++ b/lib/libm_dbl/__fpclassify.c @@ -0,0 +1,11 @@ +#include <math.h> +#include <stdint.h> + +int __fpclassifyd(double x) +{ + union {double f; uint64_t i;} u = {x}; + int e = u.i>>52 & 0x7ff; + if (!e) return u.i<<1 ? FP_SUBNORMAL : FP_ZERO; + if (e==0x7ff) return u.i<<12 ? FP_NAN : FP_INFINITE; + return FP_NORMAL; +} diff --git a/lib/libm_dbl/__rem_pio2.c b/lib/libm_dbl/__rem_pio2.c new file mode 100644 index 0000000000..d403f81c79 --- /dev/null +++ b/lib/libm_dbl/__rem_pio2.c @@ -0,0 +1,177 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/e_rem_pio2.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. + * ==================================================== + * + * Optimized by Bruce D. Evans. + */ +/* __rem_pio2(x,y) + * + * return the remainder of x rem pi/2 in y[0]+y[1] + * use __rem_pio2_large() for large x + */ + +#include "libm.h" + +#if FLT_EVAL_METHOD==0 || FLT_EVAL_METHOD==1 +#define EPS DBL_EPSILON +#elif FLT_EVAL_METHOD==2 +#define EPS LDBL_EPSILON +#endif + +/* + * invpio2: 53 bits of 2/pi + * pio2_1: first 33 bit of pi/2 + * pio2_1t: pi/2 - pio2_1 + * pio2_2: second 33 bit of pi/2 + * pio2_2t: pi/2 - (pio2_1+pio2_2) + * pio2_3: third 33 bit of pi/2 + * pio2_3t: pi/2 - (pio2_1+pio2_2+pio2_3) + */ +static const double +toint = 1.5/EPS, +invpio2 = 6.36619772367581382433e-01, /* 0x3FE45F30, 0x6DC9C883 */ +pio2_1 = 1.57079632673412561417e+00, /* 0x3FF921FB, 0x54400000 */ +pio2_1t = 6.07710050650619224932e-11, /* 0x3DD0B461, 0x1A626331 */ +pio2_2 = 6.07710050630396597660e-11, /* 0x3DD0B461, 0x1A600000 */ +pio2_2t = 2.02226624879595063154e-21, /* 0x3BA3198A, 0x2E037073 */ +pio2_3 = 2.02226624871116645580e-21, /* 0x3BA3198A, 0x2E000000 */ +pio2_3t = 8.47842766036889956997e-32; /* 0x397B839A, 0x252049C1 */ + +/* caller must handle the case when reduction is not needed: |x| ~<= pi/4 */ +int __rem_pio2(double x, double *y) +{ + union {double f; uint64_t i;} u = {x}; + double_t z,w,t,r,fn; + double tx[3],ty[2]; + uint32_t ix; + int sign, n, ex, ey, i; + + sign = u.i>>63; + ix = u.i>>32 & 0x7fffffff; + if (ix <= 0x400f6a7a) { /* |x| ~<= 5pi/4 */ + if ((ix & 0xfffff) == 0x921fb) /* |x| ~= pi/2 or 2pi/2 */ + goto medium; /* cancellation -- use medium case */ + if (ix <= 0x4002d97c) { /* |x| ~<= 3pi/4 */ + if (!sign) { + z = x - pio2_1; /* one round good to 85 bits */ + y[0] = z - pio2_1t; + y[1] = (z-y[0]) - pio2_1t; + return 1; + } else { + z = x + pio2_1; + y[0] = z + pio2_1t; + y[1] = (z-y[0]) + pio2_1t; + return -1; + } + } else { + if (!sign) { + z = x - 2*pio2_1; + y[0] = z - 2*pio2_1t; + y[1] = (z-y[0]) - 2*pio2_1t; + return 2; + } else { + z = x + 2*pio2_1; + y[0] = z + 2*pio2_1t; + y[1] = (z-y[0]) + 2*pio2_1t; + return -2; + } + } + } + if (ix <= 0x401c463b) { /* |x| ~<= 9pi/4 */ + if (ix <= 0x4015fdbc) { /* |x| ~<= 7pi/4 */ + if (ix == 0x4012d97c) /* |x| ~= 3pi/2 */ + goto medium; + if (!sign) { + z = x - 3*pio2_1; + y[0] = z - 3*pio2_1t; + y[1] = (z-y[0]) - 3*pio2_1t; + return 3; + } else { + z = x + 3*pio2_1; + y[0] = z + 3*pio2_1t; + y[1] = (z-y[0]) + 3*pio2_1t; + return -3; + } + } else { + if (ix == 0x401921fb) /* |x| ~= 4pi/2 */ + goto medium; + if (!sign) { + z = x - 4*pio2_1; + y[0] = z - 4*pio2_1t; + y[1] = (z-y[0]) - 4*pio2_1t; + return 4; + } else { + z = x + 4*pio2_1; + y[0] = z + 4*pio2_1t; + y[1] = (z-y[0]) + 4*pio2_1t; + return -4; + } + } + } + if (ix < 0x413921fb) { /* |x| ~< 2^20*(pi/2), medium size */ +medium: + /* rint(x/(pi/2)), Assume round-to-nearest. */ + fn = (double_t)x*invpio2 + toint - toint; + n = (int32_t)fn; + r = x - fn*pio2_1; + w = fn*pio2_1t; /* 1st round, good to 85 bits */ + y[0] = r - w; + u.f = y[0]; + ey = u.i>>52 & 0x7ff; + ex = ix>>20; + if (ex - ey > 16) { /* 2nd round, good to 118 bits */ + t = r; + w = fn*pio2_2; + r = t - w; + w = fn*pio2_2t - ((t-r)-w); + y[0] = r - w; + u.f = y[0]; + ey = u.i>>52 & 0x7ff; + if (ex - ey > 49) { /* 3rd round, good to 151 bits, covers all cases */ + t = r; + w = fn*pio2_3; + r = t - w; + w = fn*pio2_3t - ((t-r)-w); + y[0] = r - w; + } + } + y[1] = (r - y[0]) - w; + return n; + } + /* + * all other (large) arguments + */ + if (ix >= 0x7ff00000) { /* x is inf or NaN */ + y[0] = y[1] = x - x; + return 0; + } + /* set z = scalbn(|x|,-ilogb(x)+23) */ + u.f = x; + u.i &= (uint64_t)-1>>12; + u.i |= (uint64_t)(0x3ff + 23)<<52; + z = u.f; + for (i=0; i < 2; i++) { + tx[i] = (double)(int32_t)z; + z = (z-tx[i])*0x1p24; + } + tx[i] = z; + /* skip zero terms, first term is non-zero */ + while (tx[i] == 0.0) + i--; + n = __rem_pio2_large(tx,ty,(int)(ix>>20)-(0x3ff+23),i+1,1); + if (sign) { + y[0] = -ty[0]; + y[1] = -ty[1]; + return -n; + } + y[0] = ty[0]; + y[1] = ty[1]; + return n; +} diff --git a/lib/libm_dbl/__rem_pio2_large.c b/lib/libm_dbl/__rem_pio2_large.c new file mode 100644 index 0000000000..958f28c255 --- /dev/null +++ b/lib/libm_dbl/__rem_pio2_large.c @@ -0,0 +1,442 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/k_rem_pio2.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. + * ==================================================== + */ +/* + * __rem_pio2_large(x,y,e0,nx,prec) + * double x[],y[]; int e0,nx,prec; + * + * __rem_pio2_large return the last three digits of N with + * y = x - N*pi/2 + * so that |y| < pi/2. + * + * The method is to compute the integer (mod 8) and fraction parts of + * (2/pi)*x without doing the full multiplication. In general we + * skip the part of the product that are known to be a huge integer ( + * more accurately, = 0 mod 8 ). Thus the number of operations are + * independent of the exponent of the input. + * + * (2/pi) is represented by an array of 24-bit integers in ipio2[]. + * + * Input parameters: + * x[] The input value (must be positive) is broken into nx + * pieces of 24-bit integers in double precision format. + * x[i] will be the i-th 24 bit of x. The scaled exponent + * of x[0] is given in input parameter e0 (i.e., x[0]*2^e0 + * match x's up to 24 bits. + * + * Example of breaking a double positive z into x[0]+x[1]+x[2]: + * e0 = ilogb(z)-23 + * z = scalbn(z,-e0) + * for i = 0,1,2 + * x[i] = floor(z) + * z = (z-x[i])*2**24 + * + * + * y[] ouput result in an array of double precision numbers. + * The dimension of y[] is: + * 24-bit precision 1 + * 53-bit precision 2 + * 64-bit precision 2 + * 113-bit precision 3 + * The actual value is the sum of them. Thus for 113-bit + * precison, one may have to do something like: + * + * long double t,w,r_head, r_tail; + * t = (long double)y[2] + (long double)y[1]; + * w = (long double)y[0]; + * r_head = t+w; + * r_tail = w - (r_head - t); + * + * e0 The exponent of x[0]. Must be <= 16360 or you need to + * expand the ipio2 table. + * + * nx dimension of x[] + * + * prec an integer indicating the precision: + * 0 24 bits (single) + * 1 53 bits (double) + * 2 64 bits (extended) + * 3 113 bits (quad) + * + * External function: + * double scalbn(), floor(); + * + * + * Here is the description of some local variables: + * + * jk jk+1 is the initial number of terms of ipio2[] needed + * in the computation. The minimum and recommended value + * for jk is 3,4,4,6 for single, double, extended, and quad. + * jk+1 must be 2 larger than you might expect so that our + * recomputation test works. (Up to 24 bits in the integer + * part (the 24 bits of it that we compute) and 23 bits in + * the fraction part may be lost to cancelation before we + * recompute.) + * + * jz local integer variable indicating the number of + * terms of ipio2[] used. + * + * jx nx - 1 + * + * jv index for pointing to the suitable ipio2[] for the + * computation. In general, we want + * ( 2^e0*x[0] * ipio2[jv-1]*2^(-24jv) )/8 + * is an integer. Thus + * e0-3-24*jv >= 0 or (e0-3)/24 >= jv + * Hence jv = max(0,(e0-3)/24). + * + * jp jp+1 is the number of terms in PIo2[] needed, jp = jk. + * + * q[] double array with integral value, representing the + * 24-bits chunk of the product of x and 2/pi. + * + * q0 the corresponding exponent of q[0]. Note that the + * exponent for q[i] would be q0-24*i. + * + * PIo2[] double precision array, obtained by cutting pi/2 + * into 24 bits chunks. + * + * f[] ipio2[] in floating point + * + * iq[] integer array by breaking up q[] in 24-bits chunk. + * + * fq[] final product of x*(2/pi) in fq[0],..,fq[jk] + * + * ih integer. If >0 it indicates q[] is >= 0.5, hence + * it also indicates the *sign* of the result. + * + */ +/* + * Constants: + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough + * to produce the hexadecimal values shown. + */ + +#include "libm.h" + +static const int init_jk[] = {3,4,4,6}; /* initial value for jk */ + +/* + * Table of constants for 2/pi, 396 Hex digits (476 decimal) of 2/pi + * + * integer array, contains the (24*i)-th to (24*i+23)-th + * bit of 2/pi after binary point. The corresponding + * floating value is + * + * ipio2[i] * 2^(-24(i+1)). + * + * NB: This table must have at least (e0-3)/24 + jk terms. + * For quad precision (e0 <= 16360, jk = 6), this is 686. + */ +static const int32_t ipio2[] = { +0xA2F983, 0x6E4E44, 0x1529FC, 0x2757D1, 0xF534DD, 0xC0DB62, +0x95993C, 0x439041, 0xFE5163, 0xABDEBB, 0xC561B7, 0x246E3A, +0x424DD2, 0xE00649, 0x2EEA09, 0xD1921C, 0xFE1DEB, 0x1CB129, +0xA73EE8, 0x8235F5, 0x2EBB44, 0x84E99C, 0x7026B4, 0x5F7E41, +0x3991D6, 0x398353, 0x39F49C, 0x845F8B, 0xBDF928, 0x3B1FF8, +0x97FFDE, 0x05980F, 0xEF2F11, 0x8B5A0A, 0x6D1F6D, 0x367ECF, +0x27CB09, 0xB74F46, 0x3F669E, 0x5FEA2D, 0x7527BA, 0xC7EBE5, +0xF17B3D, 0x0739F7, 0x8A5292, 0xEA6BFB, 0x5FB11F, 0x8D5D08, +0x560330, 0x46FC7B, 0x6BABF0, 0xCFBC20, 0x9AF436, 0x1DA9E3, +0x91615E, 0xE61B08, 0x659985, 0x5F14A0, 0x68408D, 0xFFD880, +0x4D7327, 0x310606, 0x1556CA, 0x73A8C9, 0x60E27B, 0xC08C6B, + +#if LDBL_MAX_EXP > 1024 +0x47C419, 0xC367CD, 0xDCE809, 0x2A8359, 0xC4768B, 0x961CA6, +0xDDAF44, 0xD15719, 0x053EA5, 0xFF0705, 0x3F7E33, 0xE832C2, +0xDE4F98, 0x327DBB, 0xC33D26, 0xEF6B1E, 0x5EF89F, 0x3A1F35, +0xCAF27F, 0x1D87F1, 0x21907C, 0x7C246A, 0xFA6ED5, 0x772D30, +0x433B15, 0xC614B5, 0x9D19C3, 0xC2C4AD, 0x414D2C, 0x5D000C, +0x467D86, 0x2D71E3, 0x9AC69B, 0x006233, 0x7CD2B4, 0x97A7B4, +0xD55537, 0xF63ED7, 0x1810A3, 0xFC764D, 0x2A9D64, 0xABD770, +0xF87C63, 0x57B07A, 0xE71517, 0x5649C0, 0xD9D63B, 0x3884A7, +0xCB2324, 0x778AD6, 0x23545A, 0xB91F00, 0x1B0AF1, 0xDFCE19, +0xFF319F, 0x6A1E66, 0x615799, 0x47FBAC, 0xD87F7E, 0xB76522, +0x89E832, 0x60BFE6, 0xCDC4EF, 0x09366C, 0xD43F5D, 0xD7DE16, +0xDE3B58, 0x929BDE, 0x2822D2, 0xE88628, 0x4D58E2, 0x32CAC6, +0x16E308, 0xCB7DE0, 0x50C017, 0xA71DF3, 0x5BE018, 0x34132E, +0x621283, 0x014883, 0x5B8EF5, 0x7FB0AD, 0xF2E91E, 0x434A48, +0xD36710, 0xD8DDAA, 0x425FAE, 0xCE616A, 0xA4280A, 0xB499D3, +0xF2A606, 0x7F775C, 0x83C2A3, 0x883C61, 0x78738A, 0x5A8CAF, +0xBDD76F, 0x63A62D, 0xCBBFF4, 0xEF818D, 0x67C126, 0x45CA55, +0x36D9CA, 0xD2A828, 0x8D61C2, 0x77C912, 0x142604, 0x9B4612, +0xC459C4, 0x44C5C8, 0x91B24D, 0xF31700, 0xAD43D4, 0xE54929, +0x10D5FD, 0xFCBE00, 0xCC941E, 0xEECE70, 0xF53E13, 0x80F1EC, +0xC3E7B3, 0x28F8C7, 0x940593, 0x3E71C1, 0xB3092E, 0xF3450B, +0x9C1288, 0x7B20AB, 0x9FB52E, 0xC29247, 0x2F327B, 0x6D550C, +0x90A772, 0x1FE76B, 0x96CB31, 0x4A1679, 0xE27941, 0x89DFF4, +0x9794E8, 0x84E6E2, 0x973199, 0x6BED88, 0x365F5F, 0x0EFDBB, +0xB49A48, 0x6CA467, 0x427271, 0x325D8D, 0xB8159F, 0x09E5BC, +0x25318D, 0x3974F7, 0x1C0530, 0x010C0D, 0x68084B, 0x58EE2C, +0x90AA47, 0x02E774, 0x24D6BD, 0xA67DF7, 0x72486E, 0xEF169F, +0xA6948E, 0xF691B4, 0x5153D1, 0xF20ACF, 0x339820, 0x7E4BF5, +0x6863B2, 0x5F3EDD, 0x035D40, 0x7F8985, 0x295255, 0xC06437, +0x10D86D, 0x324832, 0x754C5B, 0xD4714E, 0x6E5445, 0xC1090B, +0x69F52A, 0xD56614, 0x9D0727, 0x50045D, 0xDB3BB4, 0xC576EA, +0x17F987, 0x7D6B49, 0xBA271D, 0x296996, 0xACCCC6, 0x5414AD, +0x6AE290, 0x89D988, 0x50722C, 0xBEA404, 0x940777, 0x7030F3, +0x27FC00, 0xA871EA, 0x49C266, 0x3DE064, 0x83DD97, 0x973FA3, +0xFD9443, 0x8C860D, 0xDE4131, 0x9D3992, 0x8C70DD, 0xE7B717, +0x3BDF08, 0x2B3715, 0xA0805C, 0x93805A, 0x921110, 0xD8E80F, +0xAF806C, 0x4BFFDB, 0x0F9038, 0x761859, 0x15A562, 0xBBCB61, +0xB989C7, 0xBD4010, 0x04F2D2, 0x277549, 0xF6B6EB, 0xBB22DB, +0xAA140A, 0x2F2689, 0x768364, 0x333B09, 0x1A940E, 0xAA3A51, +0xC2A31D, 0xAEEDAF, 0x12265C, 0x4DC26D, 0x9C7A2D, 0x9756C0, +0x833F03, 0xF6F009, 0x8C402B, 0x99316D, 0x07B439, 0x15200C, +0x5BC3D8, 0xC492F5, 0x4BADC6, 0xA5CA4E, 0xCD37A7, 0x36A9E6, +0x9492AB, 0x6842DD, 0xDE6319, 0xEF8C76, 0x528B68, 0x37DBFC, +0xABA1AE, 0x3115DF, 0xA1AE00, 0xDAFB0C, 0x664D64, 0xB705ED, +0x306529, 0xBF5657, 0x3AFF47, 0xB9F96A, 0xF3BE75, 0xDF9328, +0x3080AB, 0xF68C66, 0x15CB04, 0x0622FA, 0x1DE4D9, 0xA4B33D, +0x8F1B57, 0x09CD36, 0xE9424E, 0xA4BE13, 0xB52333, 0x1AAAF0, +0xA8654F, 0xA5C1D2, 0x0F3F0B, 0xCD785B, 0x76F923, 0x048B7B, +0x721789, 0x53A6C6, 0xE26E6F, 0x00EBEF, 0x584A9B, 0xB7DAC4, +0xBA66AA, 0xCFCF76, 0x1D02D1, 0x2DF1B1, 0xC1998C, 0x77ADC3, +0xDA4886, 0xA05DF7, 0xF480C6, 0x2FF0AC, 0x9AECDD, 0xBC5C3F, +0x6DDED0, 0x1FC790, 0xB6DB2A, 0x3A25A3, 0x9AAF00, 0x9353AD, +0x0457B6, 0xB42D29, 0x7E804B, 0xA707DA, 0x0EAA76, 0xA1597B, +0x2A1216, 0x2DB7DC, 0xFDE5FA, 0xFEDB89, 0xFDBE89, 0x6C76E4, +0xFCA906, 0x70803E, 0x156E85, 0xFF87FD, 0x073E28, 0x336761, +0x86182A, 0xEABD4D, 0xAFE7B3, 0x6E6D8F, 0x396795, 0x5BBF31, +0x48D784, 0x16DF30, 0x432DC7, 0x356125, 0xCE70C9, 0xB8CB30, +0xFD6CBF, 0xA200A4, 0xE46C05, 0xA0DD5A, 0x476F21, 0xD21262, +0x845CB9, 0x496170, 0xE0566B, 0x015299, 0x375550, 0xB7D51E, +0xC4F133, 0x5F6E13, 0xE4305D, 0xA92E85, 0xC3B21D, 0x3632A1, +0xA4B708, 0xD4B1EA, 0x21F716, 0xE4698F, 0x77FF27, 0x80030C, +0x2D408D, 0xA0CD4F, 0x99A520, 0xD3A2B3, 0x0A5D2F, 0x42F9B4, +0xCBDA11, 0xD0BE7D, 0xC1DB9B, 0xBD17AB, 0x81A2CA, 0x5C6A08, +0x17552E, 0x550027, 0xF0147F, 0x8607E1, 0x640B14, 0x8D4196, +0xDEBE87, 0x2AFDDA, 0xB6256B, 0x34897B, 0xFEF305, 0x9EBFB9, +0x4F6A68, 0xA82A4A, 0x5AC44F, 0xBCF82D, 0x985AD7, 0x95C7F4, +0x8D4D0D, 0xA63A20, 0x5F57A4, 0xB13F14, 0x953880, 0x0120CC, +0x86DD71, 0xB6DEC9, 0xF560BF, 0x11654D, 0x6B0701, 0xACB08C, +0xD0C0B2, 0x485551, 0x0EFB1E, 0xC37295, 0x3B06A3, 0x3540C0, +0x7BDC06, 0xCC45E0, 0xFA294E, 0xC8CAD6, 0x41F3E8, 0xDE647C, +0xD8649B, 0x31BED9, 0xC397A4, 0xD45877, 0xC5E369, 0x13DAF0, +0x3C3ABA, 0x461846, 0x5F7555, 0xF5BDD2, 0xC6926E, 0x5D2EAC, +0xED440E, 0x423E1C, 0x87C461, 0xE9FD29, 0xF3D6E7, 0xCA7C22, +0x35916F, 0xC5E008, 0x8DD7FF, 0xE26A6E, 0xC6FDB0, 0xC10893, +0x745D7C, 0xB2AD6B, 0x9D6ECD, 0x7B723E, 0x6A11C6, 0xA9CFF7, +0xDF7329, 0xBAC9B5, 0x5100B7, 0x0DB2E2, 0x24BA74, 0x607DE5, +0x8AD874, 0x2C150D, 0x0C1881, 0x94667E, 0x162901, 0x767A9F, +0xBEFDFD, 0xEF4556, 0x367ED9, 0x13D9EC, 0xB9BA8B, 0xFC97C4, +0x27A831, 0xC36EF1, 0x36C594, 0x56A8D8, 0xB5A8B4, 0x0ECCCF, +0x2D8912, 0x34576F, 0x89562C, 0xE3CE99, 0xB920D6, 0xAA5E6B, +0x9C2A3E, 0xCC5F11, 0x4A0BFD, 0xFBF4E1, 0x6D3B8E, 0x2C86E2, +0x84D4E9, 0xA9B4FC, 0xD1EEEF, 0xC9352E, 0x61392F, 0x442138, +0xC8D91B, 0x0AFC81, 0x6A4AFB, 0xD81C2F, 0x84B453, 0x8C994E, +0xCC2254, 0xDC552A, 0xD6C6C0, 0x96190B, 0xB8701A, 0x649569, +0x605A26, 0xEE523F, 0x0F117F, 0x11B5F4, 0xF5CBFC, 0x2DBC34, +0xEEBC34, 0xCC5DE8, 0x605EDD, 0x9B8E67, 0xEF3392, 0xB817C9, +0x9B5861, 0xBC57E1, 0xC68351, 0x103ED8, 0x4871DD, 0xDD1C2D, +0xA118AF, 0x462C21, 0xD7F359, 0x987AD9, 0xC0549E, 0xFA864F, +0xFC0656, 0xAE79E5, 0x362289, 0x22AD38, 0xDC9367, 0xAAE855, +0x382682, 0x9BE7CA, 0xA40D51, 0xB13399, 0x0ED7A9, 0x480569, +0xF0B265, 0xA7887F, 0x974C88, 0x36D1F9, 0xB39221, 0x4A827B, +0x21CF98, 0xDC9F40, 0x5547DC, 0x3A74E1, 0x42EB67, 0xDF9DFE, +0x5FD45E, 0xA4677B, 0x7AACBA, 0xA2F655, 0x23882B, 0x55BA41, +0x086E59, 0x862A21, 0x834739, 0xE6E389, 0xD49EE5, 0x40FB49, +0xE956FF, 0xCA0F1C, 0x8A59C5, 0x2BFA94, 0xC5C1D3, 0xCFC50F, +0xAE5ADB, 0x86C547, 0x624385, 0x3B8621, 0x94792C, 0x876110, +0x7B4C2A, 0x1A2C80, 0x12BF43, 0x902688, 0x893C78, 0xE4C4A8, +0x7BDBE5, 0xC23AC4, 0xEAF426, 0x8A67F7, 0xBF920D, 0x2BA365, +0xB1933D, 0x0B7CBD, 0xDC51A4, 0x63DD27, 0xDDE169, 0x19949A, +0x9529A8, 0x28CE68, 0xB4ED09, 0x209F44, 0xCA984E, 0x638270, +0x237C7E, 0x32B90F, 0x8EF5A7, 0xE75614, 0x08F121, 0x2A9DB5, +0x4D7E6F, 0x5119A5, 0xABF9B5, 0xD6DF82, 0x61DD96, 0x023616, +0x9F3AC4, 0xA1A283, 0x6DED72, 0x7A8D39, 0xA9B882, 0x5C326B, +0x5B2746, 0xED3400, 0x7700D2, 0x55F4FC, 0x4D5901, 0x8071E0, +#endif +}; + +static const double PIo2[] = { + 1.57079625129699707031e+00, /* 0x3FF921FB, 0x40000000 */ + 7.54978941586159635335e-08, /* 0x3E74442D, 0x00000000 */ + 5.39030252995776476554e-15, /* 0x3CF84698, 0x80000000 */ + 3.28200341580791294123e-22, /* 0x3B78CC51, 0x60000000 */ + 1.27065575308067607349e-29, /* 0x39F01B83, 0x80000000 */ + 1.22933308981111328932e-36, /* 0x387A2520, 0x40000000 */ + 2.73370053816464559624e-44, /* 0x36E38222, 0x80000000 */ + 2.16741683877804819444e-51, /* 0x3569F31D, 0x00000000 */ +}; + +int __rem_pio2_large(double *x, double *y, int e0, int nx, int prec) +{ + int32_t jz,jx,jv,jp,jk,carry,n,iq[20],i,j,k,m,q0,ih; + double z,fw,f[20],fq[20],q[20]; + + /* initialize jk*/ + jk = init_jk[prec]; + jp = jk; + + /* determine jx,jv,q0, note that 3>q0 */ + jx = nx-1; + jv = (e0-3)/24; if(jv<0) jv=0; + q0 = e0-24*(jv+1); + + /* set up f[0] to f[jx+jk] where f[jx+jk] = ipio2[jv+jk] */ + j = jv-jx; m = jx+jk; + for (i=0; i<=m; i++,j++) + f[i] = j<0 ? 0.0 : (double)ipio2[j]; + + /* compute q[0],q[1],...q[jk] */ + for (i=0; i<=jk; i++) { + for (j=0,fw=0.0; j<=jx; j++) + fw += x[j]*f[jx+i-j]; + q[i] = fw; + } + + jz = jk; +recompute: + /* distill q[] into iq[] reversingly */ + for (i=0,j=jz,z=q[jz]; j>0; i++,j--) { + fw = (double)(int32_t)(0x1p-24*z); + iq[i] = (int32_t)(z - 0x1p24*fw); + z = q[j-1]+fw; + } + + /* compute n */ + z = scalbn(z,q0); /* actual value of z */ + z -= 8.0*floor(z*0.125); /* trim off integer >= 8 */ + n = (int32_t)z; + z -= (double)n; + ih = 0; + if (q0 > 0) { /* need iq[jz-1] to determine n */ + i = iq[jz-1]>>(24-q0); n += i; + iq[jz-1] -= i<<(24-q0); + ih = iq[jz-1]>>(23-q0); + } + else if (q0 == 0) ih = iq[jz-1]>>23; + else if (z >= 0.5) ih = 2; + + if (ih > 0) { /* q > 0.5 */ + n += 1; carry = 0; + for (i=0; i<jz; i++) { /* compute 1-q */ + j = iq[i]; + if (carry == 0) { + if (j != 0) { + carry = 1; + iq[i] = 0x1000000 - j; + } + } else + iq[i] = 0xffffff - j; + } + if (q0 > 0) { /* rare case: chance is 1 in 12 */ + switch(q0) { + case 1: + iq[jz-1] &= 0x7fffff; break; + case 2: + iq[jz-1] &= 0x3fffff; break; + } + } + if (ih == 2) { + z = 1.0 - z; + if (carry != 0) + z -= scalbn(1.0,q0); + } + } + + /* check if recomputation is needed */ + if (z == 0.0) { + j = 0; + for (i=jz-1; i>=jk; i--) j |= iq[i]; + if (j == 0) { /* need recomputation */ + for (k=1; iq[jk-k]==0; k++); /* k = no. of terms needed */ + + for (i=jz+1; i<=jz+k; i++) { /* add q[jz+1] to q[jz+k] */ + f[jx+i] = (double)ipio2[jv+i]; + for (j=0,fw=0.0; j<=jx; j++) + fw += x[j]*f[jx+i-j]; + q[i] = fw; + } + jz += k; + goto recompute; + } + } + + /* chop off zero terms */ + if (z == 0.0) { + jz -= 1; + q0 -= 24; + while (iq[jz] == 0) { + jz--; + q0 -= 24; + } + } else { /* break z into 24-bit if necessary */ + z = scalbn(z,-q0); + if (z >= 0x1p24) { + fw = (double)(int32_t)(0x1p-24*z); + iq[jz] = (int32_t)(z - 0x1p24*fw); + jz += 1; + q0 += 24; + iq[jz] = (int32_t)fw; + } else + iq[jz] = (int32_t)z; + } + + /* convert integer "bit" chunk to floating-point value */ + fw = scalbn(1.0,q0); + for (i=jz; i>=0; i--) { + q[i] = fw*(double)iq[i]; + fw *= 0x1p-24; + } + + /* compute PIo2[0,...,jp]*q[jz,...,0] */ + for(i=jz; i>=0; i--) { + for (fw=0.0,k=0; k<=jp && k<=jz-i; k++) + fw += PIo2[k]*q[i+k]; + fq[jz-i] = fw; + } + + /* compress fq[] into y[] */ + switch(prec) { + case 0: + fw = 0.0; + for (i=jz; i>=0; i--) + fw += fq[i]; + y[0] = ih==0 ? fw : -fw; + break; + case 1: + case 2: + fw = 0.0; + for (i=jz; i>=0; i--) + fw += fq[i]; + // TODO: drop excess precision here once double_t is used + fw = (double)fw; + y[0] = ih==0 ? fw : -fw; + fw = fq[0]-fw; + for (i=1; i<=jz; i++) + fw += fq[i]; + y[1] = ih==0 ? fw : -fw; + break; + case 3: /* painful */ + for (i=jz; i>0; i--) { + fw = fq[i-1]+fq[i]; + fq[i] += fq[i-1]-fw; + fq[i-1] = fw; + } + for (i=jz; i>1; i--) { + fw = fq[i-1]+fq[i]; + fq[i] += fq[i-1]-fw; + fq[i-1] = fw; + } + for (fw=0.0,i=jz; i>=2; i--) + fw += fq[i]; + if (ih==0) { + y[0] = fq[0]; y[1] = fq[1]; y[2] = fw; + } else { + y[0] = -fq[0]; y[1] = -fq[1]; y[2] = -fw; + } + } + return n&7; +} diff --git a/lib/libm_dbl/__signbit.c b/lib/libm_dbl/__signbit.c new file mode 100644 index 0000000000..18c6728a50 --- /dev/null +++ b/lib/libm_dbl/__signbit.c @@ -0,0 +1,12 @@ +#include "libm.h" + +int __signbitd(double x) +{ + union { + double d; + uint64_t i; + } y = { x }; + return y.i>>63; +} + + diff --git a/lib/libm_dbl/__sin.c b/lib/libm_dbl/__sin.c new file mode 100644 index 0000000000..4030949664 --- /dev/null +++ b/lib/libm_dbl/__sin.c @@ -0,0 +1,64 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/k_sin.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. + * ==================================================== + */ +/* __sin( x, y, iy) + * kernel sin function on ~[-pi/4, pi/4] (except on -0), pi/4 ~ 0.7854 + * Input x is assumed to be bounded by ~pi/4 in magnitude. + * Input y is the tail of x. + * Input iy indicates whether y is 0. (if iy=0, y assume to be 0). + * + * Algorithm + * 1. Since sin(-x) = -sin(x), we need only to consider positive x. + * 2. Callers must return sin(-0) = -0 without calling here since our + * odd polynomial is not evaluated in a way that preserves -0. + * Callers may do the optimization sin(x) ~ x for tiny x. + * 3. sin(x) is approximated by a polynomial of degree 13 on + * [0,pi/4] + * 3 13 + * sin(x) ~ x + S1*x + ... + S6*x + * where + * + * |sin(x) 2 4 6 8 10 12 | -58 + * |----- - (1+S1*x +S2*x +S3*x +S4*x +S5*x +S6*x )| <= 2 + * | x | + * + * 4. sin(x+y) = sin(x) + sin'(x')*y + * ~ sin(x) + (1-x*x/2)*y + * For better accuracy, let + * 3 2 2 2 2 + * r = x *(S2+x *(S3+x *(S4+x *(S5+x *S6)))) + * then 3 2 + * sin(x) = x + (S1*x + (x *(r-y/2)+y)) + */ + +#include "libm.h" + +static const double +S1 = -1.66666666666666324348e-01, /* 0xBFC55555, 0x55555549 */ +S2 = 8.33333333332248946124e-03, /* 0x3F811111, 0x1110F8A6 */ +S3 = -1.98412698298579493134e-04, /* 0xBF2A01A0, 0x19C161D5 */ +S4 = 2.75573137070700676789e-06, /* 0x3EC71DE3, 0x57B1FE7D */ +S5 = -2.50507602534068634195e-08, /* 0xBE5AE5E6, 0x8A2B9CEB */ +S6 = 1.58969099521155010221e-10; /* 0x3DE5D93A, 0x5ACFD57C */ + +double __sin(double x, double y, int iy) +{ + double_t z,r,v,w; + + z = x*x; + w = z*z; + r = S2 + z*(S3 + z*S4) + z*w*(S5 + z*S6); + v = z*x; + if (iy == 0) + return x + v*(S1 + z*r); + else + return x - ((z*(0.5*y - v*r) - y) - v*S1); +} diff --git a/lib/libm_dbl/__tan.c b/lib/libm_dbl/__tan.c new file mode 100644 index 0000000000..8019844d3b --- /dev/null +++ b/lib/libm_dbl/__tan.c @@ -0,0 +1,110 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/k_tan.c */ +/* + * ==================================================== + * 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. + * ==================================================== + */ +/* __tan( x, y, k ) + * kernel tan function on ~[-pi/4, pi/4] (except on -0), pi/4 ~ 0.7854 + * Input x is assumed to be bounded by ~pi/4 in magnitude. + * Input y is the tail of x. + * Input odd indicates whether tan (if odd = 0) or -1/tan (if odd = 1) is returned. + * + * Algorithm + * 1. Since tan(-x) = -tan(x), we need only to consider positive x. + * 2. Callers must return tan(-0) = -0 without calling here since our + * odd polynomial is not evaluated in a way that preserves -0. + * Callers may do the optimization tan(x) ~ x for tiny x. + * 3. tan(x) is approximated by a odd polynomial of degree 27 on + * [0,0.67434] + * 3 27 + * tan(x) ~ x + T1*x + ... + T13*x + * where + * + * |tan(x) 2 4 26 | -59.2 + * |----- - (1+T1*x +T2*x +.... +T13*x )| <= 2 + * | x | + * + * Note: tan(x+y) = tan(x) + tan'(x)*y + * ~ tan(x) + (1+x*x)*y + * Therefore, for better accuracy in computing tan(x+y), let + * 3 2 2 2 2 + * r = x *(T2+x *(T3+x *(...+x *(T12+x *T13)))) + * then + * 3 2 + * tan(x+y) = x + (T1*x + (x *(r+y)+y)) + * + * 4. For x in [0.67434,pi/4], let y = pi/4 - x, then + * tan(x) = tan(pi/4-y) = (1-tan(y))/(1+tan(y)) + * = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y))) + */ + +#include "libm.h" + +static const double T[] = { + 3.33333333333334091986e-01, /* 3FD55555, 55555563 */ + 1.33333333333201242699e-01, /* 3FC11111, 1110FE7A */ + 5.39682539762260521377e-02, /* 3FABA1BA, 1BB341FE */ + 2.18694882948595424599e-02, /* 3F9664F4, 8406D637 */ + 8.86323982359930005737e-03, /* 3F8226E3, E96E8493 */ + 3.59207910759131235356e-03, /* 3F6D6D22, C9560328 */ + 1.45620945432529025516e-03, /* 3F57DBC8, FEE08315 */ + 5.88041240820264096874e-04, /* 3F4344D8, F2F26501 */ + 2.46463134818469906812e-04, /* 3F3026F7, 1A8D1068 */ + 7.81794442939557092300e-05, /* 3F147E88, A03792A6 */ + 7.14072491382608190305e-05, /* 3F12B80F, 32F0A7E9 */ + -1.85586374855275456654e-05, /* BEF375CB, DB605373 */ + 2.59073051863633712884e-05, /* 3EFB2A70, 74BF7AD4 */ +}, +pio4 = 7.85398163397448278999e-01, /* 3FE921FB, 54442D18 */ +pio4lo = 3.06161699786838301793e-17; /* 3C81A626, 33145C07 */ + +double __tan(double x, double y, int odd) +{ + double_t z, r, v, w, s, a; + double w0, a0; + uint32_t hx; + int big, sign; + + GET_HIGH_WORD(hx,x); + big = (hx&0x7fffffff) >= 0x3FE59428; /* |x| >= 0.6744 */ + if (big) { + sign = hx>>31; + if (sign) { + x = -x; + y = -y; + } + x = (pio4 - x) + (pio4lo - y); + 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) + s*T[0]; + w = x + r; + if (big) { + s = 1 - 2*odd; + v = s - 2.0 * (x + (r - w*w/(w + s))); + return sign ? -v : v; + } + if (!odd) + return w; + /* -1.0/(x+r) has up to 2ulp error, so compute it accurately */ + w0 = w; + SET_LOW_WORD(w0, 0); + v = r - (w0 - x); /* w0+v = r+x */ + a0 = a = -1.0 / w; + SET_LOW_WORD(a0, 0); + return a0 + a*(1.0 + a0*w0 + a0*v); +} diff --git a/lib/libm_dbl/acos.c b/lib/libm_dbl/acos.c new file mode 100644 index 0000000000..6104a32bc9 --- /dev/null +++ b/lib/libm_dbl/acos.c @@ -0,0 +1,101 @@ +/* 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); +} diff --git a/lib/libm_dbl/acosh.c b/lib/libm_dbl/acosh.c new file mode 100644 index 0000000000..badbf9081e --- /dev/null +++ b/lib/libm_dbl/acosh.c @@ -0,0 +1,24 @@ +#include "libm.h" + +#if FLT_EVAL_METHOD==2 +#undef sqrt +#define sqrt sqrtl +#endif + +/* acosh(x) = log(x + sqrt(x*x-1)) */ +double acosh(double x) +{ + union {double f; uint64_t i;} u = {.f = x}; + unsigned e = u.i >> 52 & 0x7ff; + + /* x < 1 domain error is handled in the called functions */ + + if (e < 0x3ff + 1) + /* |x| < 2, up to 2ulp error in [1,1.125] */ + return log1p(x-1 + sqrt((x-1)*(x-1)+2*(x-1))); + if (e < 0x3ff + 26) + /* |x| < 0x1p26 */ + return log(2*x - 1/(x+sqrt(x*x-1))); + /* |x| >= 0x1p26 or nan */ + return log(x) + 0.693147180559945309417232121458176568; +} diff --git a/lib/libm_dbl/asin.c b/lib/libm_dbl/asin.c new file mode 100644 index 0000000000..96b4cdfaaa --- /dev/null +++ b/lib/libm_dbl/asin.c @@ -0,0 +1,107 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/e_asin.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. + * ==================================================== + */ +/* asin(x) + * Method : + * Since asin(x) = x + x^3/6 + x^5*3/40 + x^7*15/336 + ... + * we approximate asin(x) on [0,0.5] by + * asin(x) = x + x*x^2*R(x^2) + * where + * R(x^2) is a rational approximation of (asin(x)-x)/x^3 + * and its remez error is bounded by + * |(asin(x)-x)/x^3 - R(x^2)| < 2^(-58.75) + * + * For x in [0.5,1] + * asin(x) = pi/2-2*asin(sqrt((1-x)/2)) + * Let y = (1-x), z = y/2, s := sqrt(z), and pio2_hi+pio2_lo=pi/2; + * then for x>0.98 + * asin(x) = pi/2 - 2*(s+s*z*R(z)) + * = pio2_hi - (2*(s+s*z*R(z)) - pio2_lo) + * For x<=0.98, let pio4_hi = pio2_hi/2, then + * f = hi part of s; + * c = sqrt(z) - f = (z-f*f)/(s+f) ...f+c=sqrt(z) + * and + * asin(x) = pi/2 - 2*(s+s*z*R(z)) + * = pio4_hi+(pio4-2s)-(2s*z*R(z)-pio2_lo) + * = pio4_hi+(pio4-2f)-(2s*z*R(z)-(pio2_lo+2c)) + * + * Special cases: + * if x is NaN, return x itself; + * if |x|>1, return NaN with invalid signal. + * + */ + +#include "libm.h" + +static const double +pio2_hi = 1.57079632679489655800e+00, /* 0x3FF921FB, 0x54442D18 */ +pio2_lo = 6.12323399573676603587e-17, /* 0x3C91A626, 0x33145C07 */ +/* coefficients for R(x^2) */ +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 asin(double x) +{ + double z,r,s; + 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) + /* asin(1) = +-pi/2 with inexact */ + return x*pio2_hi + 0x1p-120f; + return 0/(x-x); + } + /* |x| < 0.5 */ + if (ix < 0x3fe00000) { + /* if 0x1p-1022 <= |x| < 0x1p-26, avoid raising underflow */ + if (ix < 0x3e500000 && ix >= 0x00100000) + return x; + return x + x*R(x*x); + } + /* 1 > |x| >= 0.5 */ + z = (1 - fabs(x))*0.5; + s = sqrt(z); + r = R(z); + if (ix >= 0x3fef3333) { /* if |x| > 0.975 */ + x = pio2_hi-(2*(s+s*r)-pio2_lo); + } else { + double f,c; + /* f+c = sqrt(z) */ + f = s; + SET_LOW_WORD(f,0); + c = (z-f*f)/(s+f); + x = 0.5*pio2_hi - (2*s*r - (pio2_lo-2*c) - (0.5*pio2_hi-2*f)); + } + if (hx >> 31) + return -x; + return x; +} diff --git a/lib/libm_dbl/asinh.c b/lib/libm_dbl/asinh.c new file mode 100644 index 0000000000..0829f228ef --- /dev/null +++ b/lib/libm_dbl/asinh.c @@ -0,0 +1,28 @@ +#include "libm.h" + +/* asinh(x) = sign(x)*log(|x|+sqrt(x*x+1)) ~= x - x^3/6 + o(x^5) */ +double asinh(double x) +{ + union {double f; uint64_t i;} u = {.f = x}; + unsigned e = u.i >> 52 & 0x7ff; + unsigned s = u.i >> 63; + + /* |x| */ + u.i &= (uint64_t)-1/2; + x = u.f; + + if (e >= 0x3ff + 26) { + /* |x| >= 0x1p26 or inf or nan */ + x = log(x) + 0.693147180559945309417232121458176568; + } else if (e >= 0x3ff + 1) { + /* |x| >= 2 */ + x = log(2*x + 1/(sqrt(x*x+1)+x)); + } else if (e >= 0x3ff - 26) { + /* |x| >= 0x1p-26, up to 1.6ulp error in [0.125,0.5] */ + x = log1p(x + x*x/(sqrt(x*x+1)+1)); + } else { + /* |x| < 0x1p-26, raise inexact if x != 0 */ + FORCE_EVAL(x + 0x1p120f); + } + return s ? -x : x; +} diff --git a/lib/libm_dbl/atan.c b/lib/libm_dbl/atan.c new file mode 100644 index 0000000000..63b0ab25e3 --- /dev/null +++ b/lib/libm_dbl/atan.c @@ -0,0 +1,116 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_atan.c */ +/* + * ==================================================== + * 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. + * ==================================================== + */ +/* atan(x) + * Method + * 1. Reduce x to positive by atan(x) = -atan(-x). + * 2. According to the integer k=4t+0.25 chopped, t=x, the argument + * is further reduced to one of the following intervals and the + * arctangent of t is evaluated by the corresponding formula: + * + * [0,7/16] atan(x) = t-t^3*(a1+t^2*(a2+...(a10+t^2*a11)...) + * [7/16,11/16] atan(x) = atan(1/2) + atan( (t-0.5)/(1+t/2) ) + * [11/16.19/16] atan(x) = atan( 1 ) + atan( (t-1)/(1+t) ) + * [19/16,39/16] atan(x) = atan(3/2) + atan( (t-1.5)/(1+1.5t) ) + * [39/16,INF] atan(x) = atan(INF) + atan( -1/t ) + * + * Constants: + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough + * to produce the hexadecimal values shown. + */ + + +#include "libm.h" + +static const double atanhi[] = { + 4.63647609000806093515e-01, /* atan(0.5)hi 0x3FDDAC67, 0x0561BB4F */ + 7.85398163397448278999e-01, /* atan(1.0)hi 0x3FE921FB, 0x54442D18 */ + 9.82793723247329054082e-01, /* atan(1.5)hi 0x3FEF730B, 0xD281F69B */ + 1.57079632679489655800e+00, /* atan(inf)hi 0x3FF921FB, 0x54442D18 */ +}; + +static const double atanlo[] = { + 2.26987774529616870924e-17, /* atan(0.5)lo 0x3C7A2B7F, 0x222F65E2 */ + 3.06161699786838301793e-17, /* atan(1.0)lo 0x3C81A626, 0x33145C07 */ + 1.39033110312309984516e-17, /* atan(1.5)lo 0x3C700788, 0x7AF0CBBD */ + 6.12323399573676603587e-17, /* atan(inf)lo 0x3C91A626, 0x33145C07 */ +}; + +static const double aT[] = { + 3.33333333333329318027e-01, /* 0x3FD55555, 0x5555550D */ + -1.99999999998764832476e-01, /* 0xBFC99999, 0x9998EBC4 */ + 1.42857142725034663711e-01, /* 0x3FC24924, 0x920083FF */ + -1.11111104054623557880e-01, /* 0xBFBC71C6, 0xFE231671 */ + 9.09088713343650656196e-02, /* 0x3FB745CD, 0xC54C206E */ + -7.69187620504482999495e-02, /* 0xBFB3B0F2, 0xAF749A6D */ + 6.66107313738753120669e-02, /* 0x3FB10D66, 0xA0D03D51 */ + -5.83357013379057348645e-02, /* 0xBFADDE2D, 0x52DEFD9A */ + 4.97687799461593236017e-02, /* 0x3FA97B4B, 0x24760DEB */ + -3.65315727442169155270e-02, /* 0xBFA2B444, 0x2C6A6C2F */ + 1.62858201153657823623e-02, /* 0x3F90AD3A, 0xE322DA11 */ +}; + +double atan(double x) +{ + double_t w,s1,s2,z; + uint32_t ix,sign; + int id; + + GET_HIGH_WORD(ix, x); + sign = ix >> 31; + ix &= 0x7fffffff; + if (ix >= 0x44100000) { /* if |x| >= 2^66 */ + if (isnan(x)) + return x; + z = atanhi[3] + 0x1p-120f; + return sign ? -z : z; + } + if (ix < 0x3fdc0000) { /* |x| < 0.4375 */ + if (ix < 0x3e400000) { /* |x| < 2^-27 */ + if (ix < 0x00100000) + /* raise underflow for subnormal x */ + FORCE_EVAL((float)x); + return x; + } + id = -1; + } else { + x = fabs(x); + if (ix < 0x3ff30000) { /* |x| < 1.1875 */ + if (ix < 0x3fe60000) { /* 7/16 <= |x| < 11/16 */ + id = 0; + x = (2.0*x-1.0)/(2.0+x); + } else { /* 11/16 <= |x| < 19/16 */ + id = 1; + x = (x-1.0)/(x+1.0); + } + } else { + if (ix < 0x40038000) { /* |x| < 2.4375 */ + id = 2; + x = (x-1.5)/(1.0+1.5*x); + } else { /* 2.4375 <= |x| < 2^66 */ + id = 3; + x = -1.0/x; + } + } + } + /* end of argument reduction */ + z = x*x; + w = z*z; + /* break sum from i=0 to 10 aT[i]z**(i+1) into odd and even poly */ + s1 = z*(aT[0]+w*(aT[2]+w*(aT[4]+w*(aT[6]+w*(aT[8]+w*aT[10]))))); + s2 = w*(aT[1]+w*(aT[3]+w*(aT[5]+w*(aT[7]+w*aT[9])))); + if (id < 0) + return x - x*(s1+s2); + z = atanhi[id] - (x*(s1+s2) - atanlo[id] - x); + return sign ? -z : z; +} diff --git a/lib/libm_dbl/atan2.c b/lib/libm_dbl/atan2.c new file mode 100644 index 0000000000..91378b977a --- /dev/null +++ b/lib/libm_dbl/atan2.c @@ -0,0 +1,107 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/e_atan2.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. + * ==================================================== + * + */ +/* atan2(y,x) + * Method : + * 1. Reduce y to positive by atan2(y,x)=-atan2(-y,x). + * 2. Reduce x to positive by (if x and y are unexceptional): + * ARG (x+iy) = arctan(y/x) ... if x > 0, + * ARG (x+iy) = pi - arctan[y/(-x)] ... if x < 0, + * + * Special cases: + * + * ATAN2((anything), NaN ) is NaN; + * ATAN2(NAN , (anything) ) is NaN; + * ATAN2(+-0, +(anything but NaN)) is +-0 ; + * ATAN2(+-0, -(anything but NaN)) is +-pi ; + * ATAN2(+-(anything but 0 and NaN), 0) is +-pi/2; + * ATAN2(+-(anything but INF and NaN), +INF) is +-0 ; + * ATAN2(+-(anything but INF and NaN), -INF) is +-pi; + * ATAN2(+-INF,+INF ) is +-pi/4 ; + * ATAN2(+-INF,-INF ) is +-3pi/4; + * ATAN2(+-INF, (anything but,0,NaN, and INF)) is +-pi/2; + * + * Constants: + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough + * to produce the hexadecimal values shown. + */ + +#include "libm.h" + +static const double +pi = 3.1415926535897931160E+00, /* 0x400921FB, 0x54442D18 */ +pi_lo = 1.2246467991473531772E-16; /* 0x3CA1A626, 0x33145C07 */ + +double atan2(double y, double x) +{ + double z; + uint32_t m,lx,ly,ix,iy; + + if (isnan(x) || isnan(y)) + return x+y; + EXTRACT_WORDS(ix, lx, x); + EXTRACT_WORDS(iy, ly, y); + if (((ix-0x3ff00000) | lx) == 0) /* x = 1.0 */ + return atan(y); + m = ((iy>>31)&1) | ((ix>>30)&2); /* 2*sign(x)+sign(y) */ + ix = ix & 0x7fffffff; + iy = iy & 0x7fffffff; + + /* when y = 0 */ + if ((iy|ly) == 0) { + switch(m) { + case 0: + case 1: return y; /* atan(+-0,+anything)=+-0 */ + case 2: return pi; /* atan(+0,-anything) = pi */ + case 3: return -pi; /* atan(-0,-anything) =-pi */ + } + } + /* when x = 0 */ + if ((ix|lx) == 0) + return m&1 ? -pi/2 : pi/2; + /* when x is INF */ + if (ix == 0x7ff00000) { + if (iy == 0x7ff00000) { + switch(m) { + case 0: return pi/4; /* atan(+INF,+INF) */ + case 1: return -pi/4; /* atan(-INF,+INF) */ + case 2: return 3*pi/4; /* atan(+INF,-INF) */ + case 3: return -3*pi/4; /* atan(-INF,-INF) */ + } + } else { + switch(m) { + case 0: return 0.0; /* atan(+...,+INF) */ + case 1: return -0.0; /* atan(-...,+INF) */ + case 2: return pi; /* atan(+...,-INF) */ + case 3: return -pi; /* atan(-...,-INF) */ + } + } + } + /* |y/x| > 0x1p64 */ + if (ix+(64<<20) < iy || iy == 0x7ff00000) + return m&1 ? -pi/2 : pi/2; + + /* z = atan(|y/x|) without spurious underflow */ + if ((m&2) && iy+(64<<20) < ix) /* |y/x| < 0x1p-64, x<0 */ + z = 0; + else + z = atan(fabs(y/x)); + switch (m) { + case 0: return z; /* atan(+,+) */ + case 1: return -z; /* atan(-,+) */ + case 2: return pi - (z-pi_lo); /* atan(+,-) */ + default: /* case 3 */ + return (z-pi_lo) - pi; /* atan(-,-) */ + } +} diff --git a/lib/libm_dbl/atanh.c b/lib/libm_dbl/atanh.c new file mode 100644 index 0000000000..63a035d706 --- /dev/null +++ b/lib/libm_dbl/atanh.c @@ -0,0 +1,29 @@ +#include "libm.h" + +/* atanh(x) = log((1+x)/(1-x))/2 = log1p(2x/(1-x))/2 ~= x + x^3/3 + o(x^5) */ +double atanh(double x) +{ + union {double f; uint64_t i;} u = {.f = x}; + unsigned e = u.i >> 52 & 0x7ff; + unsigned s = u.i >> 63; + double_t y; + + /* |x| */ + u.i &= (uint64_t)-1/2; + y = u.f; + + if (e < 0x3ff - 1) { + if (e < 0x3ff - 32) { + /* handle underflow */ + if (e == 0) + FORCE_EVAL((float)y); + } else { + /* |x| < 0.5, up to 1.7ulp error */ + y = 0.5*log1p(2*y + 2*y*y/(1-y)); + } + } else { + /* avoid overflow */ + y = 0.5*log1p(2*(y/(1-y))); + } + return s ? -y : y; +} diff --git a/lib/libm_dbl/ceil.c b/lib/libm_dbl/ceil.c new file mode 100644 index 0000000000..b13e6f2d63 --- /dev/null +++ b/lib/libm_dbl/ceil.c @@ -0,0 +1,31 @@ +#include "libm.h" + +#if FLT_EVAL_METHOD==0 || FLT_EVAL_METHOD==1 +#define EPS DBL_EPSILON +#elif FLT_EVAL_METHOD==2 +#define EPS LDBL_EPSILON +#endif +static const double_t toint = 1/EPS; + +double ceil(double x) +{ + union {double f; uint64_t i;} u = {x}; + int e = u.i >> 52 & 0x7ff; + double_t y; + + if (e >= 0x3ff+52 || x == 0) + return x; + /* y = int(x) - x, where int(x) is an integer neighbor of x */ + if (u.i >> 63) + y = x - toint + toint - x; + else + y = x + toint - toint - x; + /* special case because of non-nearest rounding modes */ + if (e <= 0x3ff-1) { + FORCE_EVAL(y); + return u.i >> 63 ? -0.0 : 1; + } + if (y < 0) + return x + y + 1; + return x + y; +} diff --git a/lib/libm_dbl/cos.c b/lib/libm_dbl/cos.c new file mode 100644 index 0000000000..ee97f68bbb --- /dev/null +++ b/lib/libm_dbl/cos.c @@ -0,0 +1,77 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_cos.c */ +/* + * ==================================================== + * 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. + * ==================================================== + */ +/* cos(x) + * Return cosine function of x. + * + * kernel function: + * __sin ... sine function on [-pi/4,pi/4] + * __cos ... cosine function on [-pi/4,pi/4] + * __rem_pio2 ... argument reduction routine + * + * Method. + * Let S,C and T denote the sin, cos and tan respectively on + * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2 + * in [-pi/4 , +pi/4], and let n = k mod 4. + * We have + * + * n sin(x) cos(x) tan(x) + * ---------------------------------------------------------- + * 0 S C T + * 1 C -S -1/T + * 2 -S -C T + * 3 -C S -1/T + * ---------------------------------------------------------- + * + * Special cases: + * Let trig be any of sin, cos, or tan. + * trig(+-INF) is NaN, with signals; + * trig(NaN) is that NaN; + * + * Accuracy: + * TRIG(x) returns trig(x) nearly rounded + */ + +#include "libm.h" + +double cos(double x) +{ + double y[2]; + uint32_t ix; + unsigned n; + + GET_HIGH_WORD(ix, x); + ix &= 0x7fffffff; + + /* |x| ~< pi/4 */ + if (ix <= 0x3fe921fb) { + if (ix < 0x3e46a09e) { /* |x| < 2**-27 * sqrt(2) */ + /* raise inexact if x!=0 */ + FORCE_EVAL(x + 0x1p120f); + return 1.0; + } + return __cos(x, 0); + } + + /* cos(Inf or NaN) is NaN */ + if (ix >= 0x7ff00000) + return x-x; + + /* argument reduction */ + n = __rem_pio2(x, y); + switch (n&3) { + case 0: return __cos(y[0], y[1]); + case 1: return -__sin(y[0], y[1], 1); + case 2: return -__cos(y[0], y[1]); + default: + return __sin(y[0], y[1], 1); + } +} diff --git a/lib/libm_dbl/cosh.c b/lib/libm_dbl/cosh.c new file mode 100644 index 0000000000..100f8231d8 --- /dev/null +++ b/lib/libm_dbl/cosh.c @@ -0,0 +1,40 @@ +#include "libm.h" + +/* cosh(x) = (exp(x) + 1/exp(x))/2 + * = 1 + 0.5*(exp(x)-1)*(exp(x)-1)/exp(x) + * = 1 + x*x/2 + o(x^4) + */ +double cosh(double x) +{ + union {double f; uint64_t i;} u = {.f = x}; + uint32_t w; + double t; + + /* |x| */ + u.i &= (uint64_t)-1/2; + x = u.f; + w = u.i >> 32; + + /* |x| < log(2) */ + if (w < 0x3fe62e42) { + if (w < 0x3ff00000 - (26<<20)) { + /* raise inexact if x!=0 */ + FORCE_EVAL(x + 0x1p120f); + return 1; + } + t = expm1(x); + return 1 + t*t/(2*(1+t)); + } + + /* |x| < log(DBL_MAX) */ + if (w < 0x40862e42) { + t = exp(x); + /* note: if x>log(0x1p26) then the 1/t is not needed */ + return 0.5*(t + 1/t); + } + + /* |x| > log(DBL_MAX) or nan */ + /* note: the result is stored to handle overflow */ + t = __expo2(x); + return t; +} diff --git a/lib/libm_dbl/erf.c b/lib/libm_dbl/erf.c new file mode 100644 index 0000000000..2f30a298f9 --- /dev/null +++ b/lib/libm_dbl/erf.c @@ -0,0 +1,273 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_erf.c */ +/* + * ==================================================== + * 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. + * ==================================================== + */ +/* double erf(double x) + * double erfc(double x) + * x + * 2 |\ + * erf(x) = --------- | exp(-t*t)dt + * sqrt(pi) \| + * 0 + * + * erfc(x) = 1-erf(x) + * Note that + * erf(-x) = -erf(x) + * erfc(-x) = 2 - erfc(x) + * + * Method: + * 1. For |x| in [0, 0.84375] + * erf(x) = x + x*R(x^2) + * erfc(x) = 1 - erf(x) if x in [-.84375,0.25] + * = 0.5 + ((0.5-x)-x*R) if x in [0.25,0.84375] + * where R = P/Q where P is an odd poly of degree 8 and + * Q is an odd poly of degree 10. + * -57.90 + * | R - (erf(x)-x)/x | <= 2 + * + * + * Remark. The formula is derived by noting + * erf(x) = (2/sqrt(pi))*(x - x^3/3 + x^5/10 - x^7/42 + ....) + * and that + * 2/sqrt(pi) = 1.128379167095512573896158903121545171688 + * is close to one. The interval is chosen because the fix + * point of erf(x) is near 0.6174 (i.e., erf(x)=x when x is + * near 0.6174), and by some experiment, 0.84375 is chosen to + * guarantee the error is less than one ulp for erf. + * + * 2. For |x| in [0.84375,1.25], let s = |x| - 1, and + * c = 0.84506291151 rounded to single (24 bits) + * erf(x) = sign(x) * (c + P1(s)/Q1(s)) + * erfc(x) = (1-c) - P1(s)/Q1(s) if x > 0 + * 1+(c+P1(s)/Q1(s)) if x < 0 + * |P1/Q1 - (erf(|x|)-c)| <= 2**-59.06 + * Remark: here we use the taylor series expansion at x=1. + * erf(1+s) = erf(1) + s*Poly(s) + * = 0.845.. + P1(s)/Q1(s) + * That is, we use rational approximation to approximate + * erf(1+s) - (c = (single)0.84506291151) + * Note that |P1/Q1|< 0.078 for x in [0.84375,1.25] + * where + * P1(s) = degree 6 poly in s + * Q1(s) = degree 6 poly in s + * + * 3. For x in [1.25,1/0.35(~2.857143)], + * erfc(x) = (1/x)*exp(-x*x-0.5625+R1/S1) + * erf(x) = 1 - erfc(x) + * where + * R1(z) = degree 7 poly in z, (z=1/x^2) + * S1(z) = degree 8 poly in z + * + * 4. For x in [1/0.35,28] + * erfc(x) = (1/x)*exp(-x*x-0.5625+R2/S2) if x > 0 + * = 2.0 - (1/x)*exp(-x*x-0.5625+R2/S2) if -6<x<0 + * = 2.0 - tiny (if x <= -6) + * erf(x) = sign(x)*(1.0 - erfc(x)) if x < 6, else + * erf(x) = sign(x)*(1.0 - tiny) + * where + * R2(z) = degree 6 poly in z, (z=1/x^2) + * S2(z) = degree 7 poly in z + * + * Note1: + * To compute exp(-x*x-0.5625+R/S), let s be a single + * precision number and s := x; then + * -x*x = -s*s + (s-x)*(s+x) + * exp(-x*x-0.5626+R/S) = + * exp(-s*s-0.5625)*exp((s-x)*(s+x)+R/S); + * Note2: + * Here 4 and 5 make use of the asymptotic series + * exp(-x*x) + * erfc(x) ~ ---------- * ( 1 + Poly(1/x^2) ) + * x*sqrt(pi) + * We use rational approximation to approximate + * g(s)=f(1/x^2) = log(erfc(x)*x) - x*x + 0.5625 + * Here is the error bound for R1/S1 and R2/S2 + * |R1/S1 - f(x)| < 2**(-62.57) + * |R2/S2 - f(x)| < 2**(-61.52) + * + * 5. For inf > x >= 28 + * erf(x) = sign(x) *(1 - tiny) (raise inexact) + * erfc(x) = tiny*tiny (raise underflow) if x > 0 + * = 2 - tiny if x<0 + * + * 7. Special case: + * erf(0) = 0, erf(inf) = 1, erf(-inf) = -1, + * erfc(0) = 1, erfc(inf) = 0, erfc(-inf) = 2, + * erfc/erf(NaN) is NaN + */ + +#include "libm.h" + +static const double +erx = 8.45062911510467529297e-01, /* 0x3FEB0AC1, 0x60000000 */ +/* + * Coefficients for approximation to erf on [0,0.84375] + */ +efx8 = 1.02703333676410069053e+00, /* 0x3FF06EBA, 0x8214DB69 */ +pp0 = 1.28379167095512558561e-01, /* 0x3FC06EBA, 0x8214DB68 */ +pp1 = -3.25042107247001499370e-01, /* 0xBFD4CD7D, 0x691CB913 */ +pp2 = -2.84817495755985104766e-02, /* 0xBF9D2A51, 0xDBD7194F */ +pp3 = -5.77027029648944159157e-03, /* 0xBF77A291, 0x236668E4 */ +pp4 = -2.37630166566501626084e-05, /* 0xBEF8EAD6, 0x120016AC */ +qq1 = 3.97917223959155352819e-01, /* 0x3FD97779, 0xCDDADC09 */ +qq2 = 6.50222499887672944485e-02, /* 0x3FB0A54C, 0x5536CEBA */ +qq3 = 5.08130628187576562776e-03, /* 0x3F74D022, 0xC4D36B0F */ +qq4 = 1.32494738004321644526e-04, /* 0x3F215DC9, 0x221C1A10 */ +qq5 = -3.96022827877536812320e-06, /* 0xBED09C43, 0x42A26120 */ +/* + * Coefficients for approximation to erf in [0.84375,1.25] + */ +pa0 = -2.36211856075265944077e-03, /* 0xBF6359B8, 0xBEF77538 */ +pa1 = 4.14856118683748331666e-01, /* 0x3FDA8D00, 0xAD92B34D */ +pa2 = -3.72207876035701323847e-01, /* 0xBFD7D240, 0xFBB8C3F1 */ +pa3 = 3.18346619901161753674e-01, /* 0x3FD45FCA, 0x805120E4 */ +pa4 = -1.10894694282396677476e-01, /* 0xBFBC6398, 0x3D3E28EC */ +pa5 = 3.54783043256182359371e-02, /* 0x3FA22A36, 0x599795EB */ +pa6 = -2.16637559486879084300e-03, /* 0xBF61BF38, 0x0A96073F */ +qa1 = 1.06420880400844228286e-01, /* 0x3FBB3E66, 0x18EEE323 */ +qa2 = 5.40397917702171048937e-01, /* 0x3FE14AF0, 0x92EB6F33 */ +qa3 = 7.18286544141962662868e-02, /* 0x3FB2635C, 0xD99FE9A7 */ +qa4 = 1.26171219808761642112e-01, /* 0x3FC02660, 0xE763351F */ +qa5 = 1.36370839120290507362e-02, /* 0x3F8BEDC2, 0x6B51DD1C */ +qa6 = 1.19844998467991074170e-02, /* 0x3F888B54, 0x5735151D */ +/* + * Coefficients for approximation to erfc in [1.25,1/0.35] + */ +ra0 = -9.86494403484714822705e-03, /* 0xBF843412, 0x600D6435 */ +ra1 = -6.93858572707181764372e-01, /* 0xBFE63416, 0xE4BA7360 */ +ra2 = -1.05586262253232909814e+01, /* 0xC0251E04, 0x41B0E726 */ +ra3 = -6.23753324503260060396e+01, /* 0xC04F300A, 0xE4CBA38D */ +ra4 = -1.62396669462573470355e+02, /* 0xC0644CB1, 0x84282266 */ +ra5 = -1.84605092906711035994e+02, /* 0xC067135C, 0xEBCCABB2 */ +ra6 = -8.12874355063065934246e+01, /* 0xC0545265, 0x57E4D2F2 */ +ra7 = -9.81432934416914548592e+00, /* 0xC023A0EF, 0xC69AC25C */ +sa1 = 1.96512716674392571292e+01, /* 0x4033A6B9, 0xBD707687 */ +sa2 = 1.37657754143519042600e+02, /* 0x4061350C, 0x526AE721 */ +sa3 = 4.34565877475229228821e+02, /* 0x407B290D, 0xD58A1A71 */ +sa4 = 6.45387271733267880336e+02, /* 0x40842B19, 0x21EC2868 */ +sa5 = 4.29008140027567833386e+02, /* 0x407AD021, 0x57700314 */ +sa6 = 1.08635005541779435134e+02, /* 0x405B28A3, 0xEE48AE2C */ +sa7 = 6.57024977031928170135e+00, /* 0x401A47EF, 0x8E484A93 */ +sa8 = -6.04244152148580987438e-02, /* 0xBFAEEFF2, 0xEE749A62 */ +/* + * Coefficients for approximation to erfc in [1/.35,28] + */ +rb0 = -9.86494292470009928597e-03, /* 0xBF843412, 0x39E86F4A */ +rb1 = -7.99283237680523006574e-01, /* 0xBFE993BA, 0x70C285DE */ +rb2 = -1.77579549177547519889e+01, /* 0xC031C209, 0x555F995A */ +rb3 = -1.60636384855821916062e+02, /* 0xC064145D, 0x43C5ED98 */ +rb4 = -6.37566443368389627722e+02, /* 0xC083EC88, 0x1375F228 */ +rb5 = -1.02509513161107724954e+03, /* 0xC0900461, 0x6A2E5992 */ +rb6 = -4.83519191608651397019e+02, /* 0xC07E384E, 0x9BDC383F */ +sb1 = 3.03380607434824582924e+01, /* 0x403E568B, 0x261D5190 */ +sb2 = 3.25792512996573918826e+02, /* 0x40745CAE, 0x221B9F0A */ +sb3 = 1.53672958608443695994e+03, /* 0x409802EB, 0x189D5118 */ +sb4 = 3.19985821950859553908e+03, /* 0x40A8FFB7, 0x688C246A */ +sb5 = 2.55305040643316442583e+03, /* 0x40A3F219, 0xCEDF3BE6 */ +sb6 = 4.74528541206955367215e+02, /* 0x407DA874, 0xE79FE763 */ +sb7 = -2.24409524465858183362e+01; /* 0xC03670E2, 0x42712D62 */ + +static double erfc1(double x) +{ + double_t s,P,Q; + + s = fabs(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 double erfc2(uint32_t ix, double x) +{ + double_t s,R,S; + double z; + + if (ix < 0x3ff40000) /* |x| < 1.25 */ + return erfc1(x); + + x = fabs(x); + s = 1/(x*x); + if (ix < 0x4006db6d) { /* |x| < 1/.35 ~ 2.85714 */ + R = ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*( + ra5+s*(ra6+s*ra7)))))); + S = 1.0+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*( + sa5+s*(sa6+s*(sa7+s*sa8))))))); + } else { /* |x| > 1/.35 */ + R = rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*( + rb5+s*rb6))))); + S = 1.0+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*( + sb5+s*(sb6+s*sb7)))))); + } + z = x; + SET_LOW_WORD(z,0); + return exp(-z*z-0.5625)*exp((z-x)*(z+x)+R/S)/x; +} + +double erf(double x) +{ + double r,s,z,y; + uint32_t ix; + int sign; + + GET_HIGH_WORD(ix, x); + sign = ix>>31; + ix &= 0x7fffffff; + if (ix >= 0x7ff00000) { + /* erf(nan)=nan, erf(+-inf)=+-1 */ + return 1-2*sign + 1/x; + } + if (ix < 0x3feb0000) { /* |x| < 0.84375 */ + if (ix < 0x3e300000) { /* |x| < 2**-28 */ + /* avoid underflow */ + return 0.125*(8*x + efx8*x); + } + z = x*x; + r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4))); + s = 1.0+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5)))); + y = r/s; + return x + x*y; + } + if (ix < 0x40180000) /* 0.84375 <= |x| < 6 */ + y = 1 - erfc2(ix,x); + else + y = 1 - 0x1p-1022; + return sign ? -y : y; +} + +double erfc(double x) +{ + double r,s,z,y; + uint32_t ix; + int sign; + + GET_HIGH_WORD(ix, x); + sign = ix>>31; + ix &= 0x7fffffff; + if (ix >= 0x7ff00000) { + /* erfc(nan)=nan, erfc(+-inf)=0,2 */ + return 2*sign + 1/x; + } + if (ix < 0x3feb0000) { /* |x| < 0.84375 */ + if (ix < 0x3c700000) /* |x| < 2**-56 */ + return 1.0 - x; + z = x*x; + r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4))); + s = 1.0+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5)))); + y = r/s; + if (sign || ix < 0x3fd00000) { /* x < 1/4 */ + return 1.0 - (x+x*y); + } + return 0.5 - (x - 0.5 + x*y); + } + if (ix < 0x403c0000) { /* 0.84375 <= |x| < 28 */ + return sign ? 2 - erfc2(ix,x) : erfc2(ix,x); + } + return sign ? 2 - 0x1p-1022 : 0x1p-1022*0x1p-1022; +} diff --git a/lib/libm_dbl/exp.c b/lib/libm_dbl/exp.c new file mode 100644 index 0000000000..9ea672fac6 --- /dev/null +++ b/lib/libm_dbl/exp.c @@ -0,0 +1,134 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/e_exp.c */ +/* + * ==================================================== + * Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved. + * + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ +/* exp(x) + * Returns the exponential of x. + * + * Method + * 1. Argument reduction: + * Reduce x to an r so that |r| <= 0.5*ln2 ~ 0.34658. + * Given x, find r and integer k such that + * + * x = k*ln2 + r, |r| <= 0.5*ln2. + * + * Here r will be represented as r = hi-lo for better + * accuracy. + * + * 2. Approximation of exp(r) by a special rational function on + * the interval [0,0.34658]: + * Write + * R(r**2) = r*(exp(r)+1)/(exp(r)-1) = 2 + r*r/6 - r**4/360 + ... + * We use a special Remez algorithm on [0,0.34658] to generate + * a polynomial of degree 5 to approximate R. The maximum error + * of this polynomial approximation is bounded by 2**-59. In + * other words, + * R(z) ~ 2.0 + P1*z + P2*z**2 + P3*z**3 + P4*z**4 + P5*z**5 + * (where z=r*r, and the values of P1 to P5 are listed below) + * and + * | 5 | -59 + * | 2.0+P1*z+...+P5*z - R(z) | <= 2 + * | | + * The computation of exp(r) thus becomes + * 2*r + * exp(r) = 1 + ---------- + * R(r) - r + * r*c(r) + * = 1 + r + ----------- (for better accuracy) + * 2 - c(r) + * where + * 2 4 10 + * c(r) = r - (P1*r + P2*r + ... + P5*r ). + * + * 3. Scale back to obtain exp(x): + * From step 1, we have + * exp(x) = 2^k * exp(r) + * + * Special cases: + * exp(INF) is INF, exp(NaN) is NaN; + * exp(-INF) is 0, and + * for finite argument, only exp(0)=1 is exact. + * + * Accuracy: + * according to an error analysis, the error is always less than + * 1 ulp (unit in the last place). + * + * Misc. info. + * For IEEE double + * if x > 709.782712893383973096 then exp(x) overflows + * if x < -745.133219101941108420 then exp(x) underflows + */ + +#include "libm.h" + +static const double +half[2] = {0.5,-0.5}, +ln2hi = 6.93147180369123816490e-01, /* 0x3fe62e42, 0xfee00000 */ +ln2lo = 1.90821492927058770002e-10, /* 0x3dea39ef, 0x35793c76 */ +invln2 = 1.44269504088896338700e+00, /* 0x3ff71547, 0x652b82fe */ +P1 = 1.66666666666666019037e-01, /* 0x3FC55555, 0x5555553E */ +P2 = -2.77777777770155933842e-03, /* 0xBF66C16C, 0x16BEBD93 */ +P3 = 6.61375632143793436117e-05, /* 0x3F11566A, 0xAF25DE2C */ +P4 = -1.65339022054652515390e-06, /* 0xBEBBBD41, 0xC5D26BF1 */ +P5 = 4.13813679705723846039e-08; /* 0x3E663769, 0x72BEA4D0 */ + +double exp(double x) +{ + double_t hi, lo, c, xx, y; + int k, sign; + uint32_t hx; + + GET_HIGH_WORD(hx, x); + sign = hx>>31; + hx &= 0x7fffffff; /* high word of |x| */ + + /* special cases */ + if (hx >= 0x4086232b) { /* if |x| >= 708.39... */ + if (isnan(x)) + return x; + if (x > 709.782712893383973096) { + /* overflow if x!=inf */ + x *= 0x1p1023; + return x; + } + if (x < -708.39641853226410622) { + /* underflow if x!=-inf */ + FORCE_EVAL((float)(-0x1p-149/x)); + if (x < -745.13321910194110842) + return 0; + } + } + + /* argument reduction */ + if (hx > 0x3fd62e42) { /* if |x| > 0.5 ln2 */ + if (hx >= 0x3ff0a2b2) /* if |x| >= 1.5 ln2 */ + k = (int)(invln2*x + half[sign]); + else + k = 1 - sign - sign; + hi = x - k*ln2hi; /* k*ln2hi is exact here */ + lo = k*ln2lo; + x = hi - lo; + } else if (hx > 0x3e300000) { /* if |x| > 2**-28 */ + k = 0; + hi = x; + lo = 0; + } else { + /* inexact if x!=0 */ + FORCE_EVAL(0x1p1023 + x); + return 1 + x; + } + + /* x is now in primary range */ + xx = x*x; + c = x - xx*(P1+xx*(P2+xx*(P3+xx*(P4+xx*P5)))); + y = 1 + (x*c/(2-c) - lo + hi); + if (k == 0) + return y; + return scalbn(y, k); +} diff --git a/lib/libm_dbl/expm1.c b/lib/libm_dbl/expm1.c new file mode 100644 index 0000000000..ac1e61e4f7 --- /dev/null +++ b/lib/libm_dbl/expm1.c @@ -0,0 +1,201 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_expm1.c */ +/* + * ==================================================== + * 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. + * ==================================================== + */ +/* expm1(x) + * Returns exp(x)-1, the exponential of x minus 1. + * + * Method + * 1. Argument reduction: + * Given x, find r and integer k such that + * + * x = k*ln2 + r, |r| <= 0.5*ln2 ~ 0.34658 + * + * Here a correction term c will be computed to compensate + * the error in r when rounded to a floating-point number. + * + * 2. Approximating expm1(r) by a special rational function on + * the interval [0,0.34658]: + * Since + * r*(exp(r)+1)/(exp(r)-1) = 2+ r^2/6 - r^4/360 + ... + * we define R1(r*r) by + * r*(exp(r)+1)/(exp(r)-1) = 2+ r^2/6 * R1(r*r) + * That is, + * R1(r**2) = 6/r *((exp(r)+1)/(exp(r)-1) - 2/r) + * = 6/r * ( 1 + 2.0*(1/(exp(r)-1) - 1/r)) + * = 1 - r^2/60 + r^4/2520 - r^6/100800 + ... + * We use a special Remez algorithm on [0,0.347] to generate + * a polynomial of degree 5 in r*r to approximate R1. The + * maximum error of this polynomial approximation is bounded + * by 2**-61. In other words, + * R1(z) ~ 1.0 + Q1*z + Q2*z**2 + Q3*z**3 + Q4*z**4 + Q5*z**5 + * where Q1 = -1.6666666666666567384E-2, + * Q2 = 3.9682539681370365873E-4, + * Q3 = -9.9206344733435987357E-6, + * Q4 = 2.5051361420808517002E-7, + * Q5 = -6.2843505682382617102E-9; + * z = r*r, + * with error bounded by + * | 5 | -61 + * | 1.0+Q1*z+...+Q5*z - R1(z) | <= 2 + * | | + * + * expm1(r) = exp(r)-1 is then computed by the following + * specific way which minimize the accumulation rounding error: + * 2 3 + * r r [ 3 - (R1 + R1*r/2) ] + * expm1(r) = r + --- + --- * [--------------------] + * 2 2 [ 6 - r*(3 - R1*r/2) ] + * + * To compensate the error in the argument reduction, we use + * expm1(r+c) = expm1(r) + c + expm1(r)*c + * ~ expm1(r) + c + r*c + * Thus c+r*c will be added in as the correction terms for + * expm1(r+c). Now rearrange the term to avoid optimization + * screw up: + * ( 2 2 ) + * ({ ( r [ R1 - (3 - R1*r/2) ] ) } r ) + * expm1(r+c)~r - ({r*(--- * [--------------------]-c)-c} - --- ) + * ({ ( 2 [ 6 - r*(3 - R1*r/2) ] ) } 2 ) + * ( ) + * + * = r - E + * 3. Scale back to obtain expm1(x): + * From step 1, we have + * expm1(x) = either 2^k*[expm1(r)+1] - 1 + * = or 2^k*[expm1(r) + (1-2^-k)] + * 4. Implementation notes: + * (A). To save one multiplication, we scale the coefficient Qi + * to Qi*2^i, and replace z by (x^2)/2. + * (B). To achieve maximum accuracy, we compute expm1(x) by + * (i) if x < -56*ln2, return -1.0, (raise inexact if x!=inf) + * (ii) if k=0, return r-E + * (iii) if k=-1, return 0.5*(r-E)-0.5 + * (iv) if k=1 if r < -0.25, return 2*((r+0.5)- E) + * else return 1.0+2.0*(r-E); + * (v) if (k<-2||k>56) return 2^k(1-(E-r)) - 1 (or exp(x)-1) + * (vi) if k <= 20, return 2^k((1-2^-k)-(E-r)), else + * (vii) return 2^k(1-((E+2^-k)-r)) + * + * Special cases: + * expm1(INF) is INF, expm1(NaN) is NaN; + * expm1(-INF) is -1, and + * for finite argument, only expm1(0)=0 is exact. + * + * Accuracy: + * according to an error analysis, the error is always less than + * 1 ulp (unit in the last place). + * + * Misc. info. + * For IEEE double + * if x > 7.09782712893383973096e+02 then expm1(x) overflow + * + * Constants: + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough + * to produce the hexadecimal values shown. + */ + +#include "libm.h" + +static const double +o_threshold = 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */ +ln2_hi = 6.93147180369123816490e-01, /* 0x3fe62e42, 0xfee00000 */ +ln2_lo = 1.90821492927058770002e-10, /* 0x3dea39ef, 0x35793c76 */ +invln2 = 1.44269504088896338700e+00, /* 0x3ff71547, 0x652b82fe */ +/* Scaled Q's: Qn_here = 2**n * Qn_above, for R(2*z) where z = hxs = x*x/2: */ +Q1 = -3.33333333333331316428e-02, /* BFA11111 111110F4 */ +Q2 = 1.58730158725481460165e-03, /* 3F5A01A0 19FE5585 */ +Q3 = -7.93650757867487942473e-05, /* BF14CE19 9EAADBB7 */ +Q4 = 4.00821782732936239552e-06, /* 3ED0CFCA 86E65239 */ +Q5 = -2.01099218183624371326e-07; /* BE8AFDB7 6E09C32D */ + +double expm1(double x) +{ + double_t y,hi,lo,c,t,e,hxs,hfx,r1,twopk; + union {double f; uint64_t i;} u = {x}; + uint32_t hx = u.i>>32 & 0x7fffffff; + int k, sign = u.i>>63; + + /* filter out huge and non-finite argument */ + if (hx >= 0x4043687A) { /* if |x|>=56*ln2 */ + if (isnan(x)) + return x; + if (sign) + return -1; + if (x > o_threshold) { + x *= 0x1p1023; + return x; + } + } + + /* argument reduction */ + if (hx > 0x3fd62e42) { /* if |x| > 0.5 ln2 */ + if (hx < 0x3FF0A2B2) { /* and |x| < 1.5 ln2 */ + if (!sign) { + hi = x - ln2_hi; + lo = ln2_lo; + k = 1; + } else { + hi = x + ln2_hi; + lo = -ln2_lo; + k = -1; + } + } else { + k = invln2*x + (sign ? -0.5 : 0.5); + t = k; + hi = x - t*ln2_hi; /* t*ln2_hi is exact here */ + lo = t*ln2_lo; + } + x = hi-lo; + c = (hi-x)-lo; + } else if (hx < 0x3c900000) { /* |x| < 2**-54, return x */ + if (hx < 0x00100000) + FORCE_EVAL((float)x); + return x; + } else + k = 0; + + /* x is now in primary range */ + hfx = 0.5*x; + hxs = x*hfx; + r1 = 1.0+hxs*(Q1+hxs*(Q2+hxs*(Q3+hxs*(Q4+hxs*Q5)))); + t = 3.0-r1*hfx; + e = hxs*((r1-t)/(6.0 - x*t)); + if (k == 0) /* c is 0 */ + return x - (x*e-hxs); + e = x*(e-c) - c; + e -= hxs; + /* exp(x) ~ 2^k (x_reduced - e + 1) */ + if (k == -1) + return 0.5*(x-e) - 0.5; + if (k == 1) { + if (x < -0.25) + return -2.0*(e-(x+0.5)); + return 1.0+2.0*(x-e); + } + u.i = (uint64_t)(0x3ff + k)<<52; /* 2^k */ + twopk = u.f; + if (k < 0 || k > 56) { /* suffice to return exp(x)-1 */ + y = x - e + 1.0; + if (k == 1024) + y = y*2.0*0x1p1023; + else + y = y*twopk; + return y - 1.0; + } + u.i = (uint64_t)(0x3ff - k)<<52; /* 2^-k */ + if (k < 20) + y = (x-e+(1-u.f))*twopk; + else + y = (x-(e+u.f)+1)*twopk; + return y; +} diff --git a/lib/libm_dbl/floor.c b/lib/libm_dbl/floor.c new file mode 100644 index 0000000000..14a31cd8c4 --- /dev/null +++ b/lib/libm_dbl/floor.c @@ -0,0 +1,31 @@ +#include "libm.h" + +#if FLT_EVAL_METHOD==0 || FLT_EVAL_METHOD==1 +#define EPS DBL_EPSILON +#elif FLT_EVAL_METHOD==2 +#define EPS LDBL_EPSILON +#endif +static const double_t toint = 1/EPS; + +double floor(double x) +{ + union {double f; uint64_t i;} u = {x}; + int e = u.i >> 52 & 0x7ff; + double_t y; + + if (e >= 0x3ff+52 || x == 0) + return x; + /* y = int(x) - x, where int(x) is an integer neighbor of x */ + if (u.i >> 63) + y = x - toint + toint - x; + else + y = x + toint - toint - x; + /* special case because of non-nearest rounding modes */ + if (e <= 0x3ff-1) { + FORCE_EVAL(y); + return u.i >> 63 ? -1 : 0; + } + if (y > 0) + return x + y - 1; + return x + y; +} diff --git a/lib/libm_dbl/fmod.c b/lib/libm_dbl/fmod.c new file mode 100644 index 0000000000..6849722bac --- /dev/null +++ b/lib/libm_dbl/fmod.c @@ -0,0 +1,68 @@ +#include <math.h> +#include <stdint.h> + +double fmod(double x, double y) +{ + union {double f; uint64_t i;} ux = {x}, uy = {y}; + int ex = ux.i>>52 & 0x7ff; + int ey = uy.i>>52 & 0x7ff; + int sx = ux.i>>63; + uint64_t i; + + /* in the followings uxi should be ux.i, but then gcc wrongly adds */ + /* float load/store to inner loops ruining performance and code size */ + uint64_t uxi = ux.i; + + if (uy.i<<1 == 0 || isnan(y) || ex == 0x7ff) + return (x*y)/(x*y); + if (uxi<<1 <= uy.i<<1) { + if (uxi<<1 == uy.i<<1) + return 0*x; + return x; + } + + /* normalize x and y */ + if (!ex) { + for (i = uxi<<12; i>>63 == 0; ex--, i <<= 1); + uxi <<= -ex + 1; + } else { + uxi &= -1ULL >> 12; + uxi |= 1ULL << 52; + } + if (!ey) { + for (i = uy.i<<12; i>>63 == 0; ey--, i <<= 1); + uy.i <<= -ey + 1; + } else { + uy.i &= -1ULL >> 12; + uy.i |= 1ULL << 52; + } + + /* x mod y */ + for (; ex > ey; ex--) { + i = uxi - uy.i; + if (i >> 63 == 0) { + if (i == 0) + return 0*x; + uxi = i; + } + uxi <<= 1; + } + i = uxi - uy.i; + if (i >> 63 == 0) { + if (i == 0) + return 0*x; + uxi = i; + } + for (; uxi>>52 == 0; uxi <<= 1, ex--); + + /* scale result */ + if (ex > 0) { + uxi -= 1ULL << 52; + uxi |= (uint64_t)ex << 52; + } else { + uxi >>= -ex + 1; + } + uxi |= (uint64_t)sx << 63; + ux.i = uxi; + return ux.f; +} diff --git a/lib/libm_dbl/frexp.c b/lib/libm_dbl/frexp.c new file mode 100644 index 0000000000..27b6266ed0 --- /dev/null +++ b/lib/libm_dbl/frexp.c @@ -0,0 +1,23 @@ +#include <math.h> +#include <stdint.h> + +double frexp(double x, int *e) +{ + union { double d; uint64_t i; } y = { x }; + int ee = y.i>>52 & 0x7ff; + + if (!ee) { + if (x) { + x = frexp(x*0x1p64, e); + *e -= 64; + } else *e = 0; + return x; + } else if (ee == 0x7ff) { + return x; + } + + *e = ee - 0x3fe; + y.i &= 0x800fffffffffffffull; + y.i |= 0x3fe0000000000000ull; + return y.d; +} diff --git a/lib/libm_dbl/ldexp.c b/lib/libm_dbl/ldexp.c new file mode 100644 index 0000000000..f4d1cd6af5 --- /dev/null +++ b/lib/libm_dbl/ldexp.c @@ -0,0 +1,6 @@ +#include <math.h> + +double ldexp(double x, int n) +{ + return scalbn(x, n); +} diff --git a/lib/libm_dbl/lgamma.c b/lib/libm_dbl/lgamma.c new file mode 100644 index 0000000000..ed193da17d --- /dev/null +++ b/lib/libm_dbl/lgamma.c @@ -0,0 +1,8 @@ +#include <math.h> + +double __lgamma_r(double, int*); + +double lgamma(double x) { + int sign; + return __lgamma_r(x, &sign); +} diff --git a/lib/libm_dbl/libm.h b/lib/libm_dbl/libm.h new file mode 100644 index 0000000000..dc0b431a44 --- /dev/null +++ b/lib/libm_dbl/libm.h @@ -0,0 +1,96 @@ +// Portions of this file are extracted from musl-1.1.16 src/internal/libm.h + +/* origin: FreeBSD /usr/src/lib/msun/src/math_private.h */ +/* + * ==================================================== + * 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 <stdint.h> +#include <math.h> + +#define FLT_EVAL_METHOD 0 + +#define FORCE_EVAL(x) do { \ + if (sizeof(x) == sizeof(float)) { \ + volatile float __x; \ + __x = (x); \ + (void)__x; \ + } else if (sizeof(x) == sizeof(double)) { \ + volatile double __x; \ + __x = (x); \ + (void)__x; \ + } else { \ + volatile long double __x; \ + __x = (x); \ + (void)__x; \ + } \ +} while(0) + +/* Get two 32 bit ints from a double. */ +#define EXTRACT_WORDS(hi,lo,d) \ +do { \ + union {double f; uint64_t i;} __u; \ + __u.f = (d); \ + (hi) = __u.i >> 32; \ + (lo) = (uint32_t)__u.i; \ +} while (0) + +/* Get the more significant 32 bit int from a double. */ +#define GET_HIGH_WORD(hi,d) \ +do { \ + union {double f; uint64_t i;} __u; \ + __u.f = (d); \ + (hi) = __u.i >> 32; \ +} while (0) + +/* Get the less significant 32 bit int from a double. */ +#define GET_LOW_WORD(lo,d) \ +do { \ + union {double f; uint64_t i;} __u; \ + __u.f = (d); \ + (lo) = (uint32_t)__u.i; \ +} while (0) + +/* Set a double from two 32 bit ints. */ +#define INSERT_WORDS(d,hi,lo) \ +do { \ + union {double f; uint64_t i;} __u; \ + __u.i = ((uint64_t)(hi)<<32) | (uint32_t)(lo); \ + (d) = __u.f; \ +} while (0) + +/* Set the more significant 32 bits of a double from an int. */ +#define SET_HIGH_WORD(d,hi) \ +do { \ + union {double f; uint64_t i;} __u; \ + __u.f = (d); \ + __u.i &= 0xffffffff; \ + __u.i |= (uint64_t)(hi) << 32; \ + (d) = __u.f; \ +} while (0) + +/* Set the less significant 32 bits of a double from an int. */ +#define SET_LOW_WORD(d,lo) \ +do { \ + union {double f; uint64_t i;} __u; \ + __u.f = (d); \ + __u.i &= 0xffffffff00000000ull; \ + __u.i |= (uint32_t)(lo); \ + (d) = __u.f; \ +} while (0) + +#define DBL_EPSILON 2.22044604925031308085e-16 + +int __rem_pio2(double, double*); +int __rem_pio2_large(double*, double*, int, int, int); +double __sin(double, double, int); +double __cos(double, double); +double __tan(double, double, int); +double __expo2(double); diff --git a/lib/libm_dbl/log.c b/lib/libm_dbl/log.c new file mode 100644 index 0000000000..e61e113d41 --- /dev/null +++ b/lib/libm_dbl/log.c @@ -0,0 +1,118 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/e_log.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. + * ==================================================== + */ +/* log(x) + * Return the logarithm of x + * + * Method : + * 1. Argument Reduction: find k and f such that + * x = 2^k * (1+f), + * where sqrt(2)/2 < 1+f < sqrt(2) . + * + * 2. Approximation of log(1+f). + * Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s) + * = 2s + 2/3 s**3 + 2/5 s**5 + ....., + * = 2s + s*R + * We use a special Remez algorithm on [0,0.1716] to generate + * a polynomial of degree 14 to approximate R The maximum error + * of this polynomial approximation is bounded by 2**-58.45. In + * other words, + * 2 4 6 8 10 12 14 + * R(z) ~ Lg1*s +Lg2*s +Lg3*s +Lg4*s +Lg5*s +Lg6*s +Lg7*s + * (the values of Lg1 to Lg7 are listed in the program) + * and + * | 2 14 | -58.45 + * | Lg1*s +...+Lg7*s - R(z) | <= 2 + * | | + * Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2. + * In order to guarantee error in log below 1ulp, we compute log + * by + * log(1+f) = f - s*(f - R) (if f is not too large) + * log(1+f) = f - (hfsq - s*(hfsq+R)). (better accuracy) + * + * 3. Finally, log(x) = k*ln2 + log(1+f). + * = k*ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*ln2_lo))) + * Here ln2 is split into two floating point number: + * ln2_hi + ln2_lo, + * where n*ln2_hi is always exact for |n| < 2000. + * + * Special cases: + * log(x) is NaN with signal if x < 0 (including -INF) ; + * log(+INF) is +INF; log(0) is -INF with signal; + * log(NaN) is that NaN with no signal. + * + * Accuracy: + * according to an error analysis, the error is always less than + * 1 ulp (unit in the last place). + * + * Constants: + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough + * to produce the hexadecimal values shown. + */ + +#include <math.h> +#include <stdint.h> + +static const double +ln2_hi = 6.93147180369123816490e-01, /* 3fe62e42 fee00000 */ +ln2_lo = 1.90821492927058770002e-10, /* 3dea39ef 35793c76 */ +Lg1 = 6.666666666666735130e-01, /* 3FE55555 55555593 */ +Lg2 = 3.999999999940941908e-01, /* 3FD99999 9997FA04 */ +Lg3 = 2.857142874366239149e-01, /* 3FD24924 94229359 */ +Lg4 = 2.222219843214978396e-01, /* 3FCC71C5 1D8E78AF */ +Lg5 = 1.818357216161805012e-01, /* 3FC74664 96CB03DE */ +Lg6 = 1.531383769920937332e-01, /* 3FC39A09 D078C69F */ +Lg7 = 1.479819860511658591e-01; /* 3FC2F112 DF3E5244 */ + +double log(double x) +{ + union {double f; uint64_t i;} u = {x}; + double_t hfsq,f,s,z,R,w,t1,t2,dk; + uint32_t hx; + int k; + + hx = u.i>>32; + k = 0; + if (hx < 0x00100000 || hx>>31) { + if (u.i<<1 == 0) + return -1/(x*x); /* log(+-0)=-inf */ + if (hx>>31) + return (x-x)/0.0; /* log(-#) = NaN */ + /* subnormal number, scale x up */ + k -= 54; + x *= 0x1p54; + u.f = x; + hx = u.i>>32; + } else if (hx >= 0x7ff00000) { + return x; + } else if (hx == 0x3ff00000 && u.i<<32 == 0) + return 0; + + /* reduce x into [sqrt(2)/2, sqrt(2)] */ + hx += 0x3ff00000 - 0x3fe6a09e; + k += (int)(hx>>20) - 0x3ff; + hx = (hx&0x000fffff) + 0x3fe6a09e; + u.i = (uint64_t)hx<<32 | (u.i&0xffffffff); + x = u.f; + + f = x - 1.0; + hfsq = 0.5*f*f; + s = f/(2.0+f); + z = s*s; + w = z*z; + t1 = w*(Lg2+w*(Lg4+w*Lg6)); + t2 = z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7))); + R = t2 + t1; + dk = k; + return s*(hfsq+R) + dk*ln2_lo - hfsq + f + dk*ln2_hi; +} diff --git a/lib/libm_dbl/log10.c b/lib/libm_dbl/log10.c new file mode 100644 index 0000000000..bddedd6829 --- /dev/null +++ b/lib/libm_dbl/log10.c @@ -0,0 +1,7 @@ +#include <math.h> + +static const double _M_LN10 = 2.302585092994046; + +double log10(double x) { + return log(x) / (double)_M_LN10; +} diff --git a/lib/libm_dbl/log1p.c b/lib/libm_dbl/log1p.c new file mode 100644 index 0000000000..0097134940 --- /dev/null +++ b/lib/libm_dbl/log1p.c @@ -0,0 +1,122 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_log1p.c */ +/* + * ==================================================== + * 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. + * ==================================================== + */ +/* double log1p(double x) + * Return the natural logarithm of 1+x. + * + * Method : + * 1. Argument Reduction: find k and f such that + * 1+x = 2^k * (1+f), + * where sqrt(2)/2 < 1+f < sqrt(2) . + * + * Note. If k=0, then f=x is exact. However, if k!=0, then f + * may not be representable exactly. In that case, a correction + * term is need. Let u=1+x rounded. Let c = (1+x)-u, then + * log(1+x) - log(u) ~ c/u. Thus, we proceed to compute log(u), + * and add back the correction term c/u. + * (Note: when x > 2**53, one can simply return log(x)) + * + * 2. Approximation of log(1+f): See log.c + * + * 3. Finally, log1p(x) = k*ln2 + log(1+f) + c/u. See log.c + * + * Special cases: + * log1p(x) is NaN with signal if x < -1 (including -INF) ; + * log1p(+INF) is +INF; log1p(-1) is -INF with signal; + * log1p(NaN) is that NaN with no signal. + * + * Accuracy: + * according to an error analysis, the error is always less than + * 1 ulp (unit in the last place). + * + * Constants: + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough + * to produce the hexadecimal values shown. + * + * Note: Assuming log() return accurate answer, the following + * algorithm can be used to compute log1p(x) to within a few ULP: + * + * u = 1+x; + * if(u==1.0) return x ; else + * return log(u)*(x/(u-1.0)); + * + * See HP-15C Advanced Functions Handbook, p.193. + */ + +#include "libm.h" + +static const double +ln2_hi = 6.93147180369123816490e-01, /* 3fe62e42 fee00000 */ +ln2_lo = 1.90821492927058770002e-10, /* 3dea39ef 35793c76 */ +Lg1 = 6.666666666666735130e-01, /* 3FE55555 55555593 */ +Lg2 = 3.999999999940941908e-01, /* 3FD99999 9997FA04 */ +Lg3 = 2.857142874366239149e-01, /* 3FD24924 94229359 */ +Lg4 = 2.222219843214978396e-01, /* 3FCC71C5 1D8E78AF */ +Lg5 = 1.818357216161805012e-01, /* 3FC74664 96CB03DE */ +Lg6 = 1.531383769920937332e-01, /* 3FC39A09 D078C69F */ +Lg7 = 1.479819860511658591e-01; /* 3FC2F112 DF3E5244 */ + +double log1p(double x) +{ + union {double f; uint64_t i;} u = {x}; + double_t hfsq,f,c,s,z,R,w,t1,t2,dk; + uint32_t hx,hu; + int k; + + hx = u.i>>32; + k = 1; + if (hx < 0x3fda827a || hx>>31) { /* 1+x < sqrt(2)+ */ + if (hx >= 0xbff00000) { /* x <= -1.0 */ + if (x == -1) + return x/0.0; /* log1p(-1) = -inf */ + return (x-x)/0.0; /* log1p(x<-1) = NaN */ + } + if (hx<<1 < 0x3ca00000<<1) { /* |x| < 2**-53 */ + /* underflow if subnormal */ + if ((hx&0x7ff00000) == 0) + FORCE_EVAL((float)x); + return x; + } + if (hx <= 0xbfd2bec4) { /* sqrt(2)/2- <= 1+x < sqrt(2)+ */ + k = 0; + c = 0; + f = x; + } + } else if (hx >= 0x7ff00000) + return x; + if (k) { + u.f = 1 + x; + hu = u.i>>32; + hu += 0x3ff00000 - 0x3fe6a09e; + k = (int)(hu>>20) - 0x3ff; + /* correction term ~ log(1+x)-log(u), avoid underflow in c/u */ + if (k < 54) { + c = k >= 2 ? 1-(u.f-x) : x-(u.f-1); + c /= u.f; + } else + c = 0; + /* reduce u into [sqrt(2)/2, sqrt(2)] */ + hu = (hu&0x000fffff) + 0x3fe6a09e; + u.i = (uint64_t)hu<<32 | (u.i&0xffffffff); + f = u.f - 1; + } + hfsq = 0.5*f*f; + s = f/(2.0+f); + z = s*s; + w = z*z; + t1 = w*(Lg2+w*(Lg4+w*Lg6)); + t2 = z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7))); + R = t2 + t1; + dk = k; + return s*(hfsq+R) + (dk*ln2_lo+c) - hfsq + f + dk*ln2_hi; +} diff --git a/lib/libm_dbl/modf.c b/lib/libm_dbl/modf.c new file mode 100644 index 0000000000..1c8a1db90d --- /dev/null +++ b/lib/libm_dbl/modf.c @@ -0,0 +1,34 @@ +#include "libm.h" + +double modf(double x, double *iptr) +{ + union {double f; uint64_t i;} u = {x}; + uint64_t mask; + int e = (int)(u.i>>52 & 0x7ff) - 0x3ff; + + /* no fractional part */ + if (e >= 52) { + *iptr = x; + if (e == 0x400 && u.i<<12 != 0) /* nan */ + return x; + u.i &= 1ULL<<63; + return u.f; + } + + /* no integral part*/ + if (e < 0) { + u.i &= 1ULL<<63; + *iptr = u.f; + return x; + } + + mask = -1ULL>>12>>e; + if ((u.i & mask) == 0) { + *iptr = x; + u.i &= 1ULL<<63; + return u.f; + } + u.i &= ~mask; + *iptr = u.f; + return x - u.f; +} diff --git a/lib/libm_dbl/nearbyint.c b/lib/libm_dbl/nearbyint.c new file mode 100644 index 0000000000..6e9b0c1f78 --- /dev/null +++ b/lib/libm_dbl/nearbyint.c @@ -0,0 +1,20 @@ +//#include <fenv.h> +#include <math.h> + +/* nearbyint is the same as rint, but it must not raise the inexact exception */ + +double nearbyint(double x) +{ +#ifdef FE_INEXACT + #pragma STDC FENV_ACCESS ON + int e; + + e = fetestexcept(FE_INEXACT); +#endif + x = rint(x); +#ifdef FE_INEXACT + if (!e) + feclearexcept(FE_INEXACT); +#endif + return x; +} diff --git a/lib/libm_dbl/pow.c b/lib/libm_dbl/pow.c new file mode 100644 index 0000000000..3ddc1b6ff8 --- /dev/null +++ b/lib/libm_dbl/pow.c @@ -0,0 +1,328 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/e_pow.c */ +/* + * ==================================================== + * Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved. + * + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ +/* pow(x,y) return x**y + * + * n + * Method: Let x = 2 * (1+f) + * 1. Compute and return log2(x) in two pieces: + * log2(x) = w1 + w2, + * where w1 has 53-24 = 29 bit trailing zeros. + * 2. Perform y*log2(x) = n+y' by simulating muti-precision + * arithmetic, where |y'|<=0.5. + * 3. Return x**y = 2**n*exp(y'*log2) + * + * Special cases: + * 1. (anything) ** 0 is 1 + * 2. 1 ** (anything) is 1 + * 3. (anything except 1) ** NAN is NAN + * 4. NAN ** (anything except 0) is NAN + * 5. +-(|x| > 1) ** +INF is +INF + * 6. +-(|x| > 1) ** -INF is +0 + * 7. +-(|x| < 1) ** +INF is +0 + * 8. +-(|x| < 1) ** -INF is +INF + * 9. -1 ** +-INF is 1 + * 10. +0 ** (+anything except 0, NAN) is +0 + * 11. -0 ** (+anything except 0, NAN, odd integer) is +0 + * 12. +0 ** (-anything except 0, NAN) is +INF, raise divbyzero + * 13. -0 ** (-anything except 0, NAN, odd integer) is +INF, raise divbyzero + * 14. -0 ** (+odd integer) is -0 + * 15. -0 ** (-odd integer) is -INF, raise divbyzero + * 16. +INF ** (+anything except 0,NAN) is +INF + * 17. +INF ** (-anything except 0,NAN) is +0 + * 18. -INF ** (+odd integer) is -INF + * 19. -INF ** (anything) = -0 ** (-anything), (anything except odd integer) + * 20. (anything) ** 1 is (anything) + * 21. (anything) ** -1 is 1/(anything) + * 22. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer) + * 23. (-anything except 0 and inf) ** (non-integer) is NAN + * + * Accuracy: + * pow(x,y) returns x**y nearly rounded. In particular + * pow(integer,integer) + * always returns the correct integer provided it is + * representable. + * + * Constants : + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough + * to produce the hexadecimal values shown. + */ + +#include "libm.h" + +static const double +bp[] = {1.0, 1.5,}, +dp_h[] = { 0.0, 5.84962487220764160156e-01,}, /* 0x3FE2B803, 0x40000000 */ +dp_l[] = { 0.0, 1.35003920212974897128e-08,}, /* 0x3E4CFDEB, 0x43CFD006 */ +two53 = 9007199254740992.0, /* 0x43400000, 0x00000000 */ +huge = 1.0e300, +tiny = 1.0e-300, +/* poly coefs for (3/2)*(log(x)-2s-2/3*s**3 */ +L1 = 5.99999999999994648725e-01, /* 0x3FE33333, 0x33333303 */ +L2 = 4.28571428578550184252e-01, /* 0x3FDB6DB6, 0xDB6FABFF */ +L3 = 3.33333329818377432918e-01, /* 0x3FD55555, 0x518F264D */ +L4 = 2.72728123808534006489e-01, /* 0x3FD17460, 0xA91D4101 */ +L5 = 2.30660745775561754067e-01, /* 0x3FCD864A, 0x93C9DB65 */ +L6 = 2.06975017800338417784e-01, /* 0x3FCA7E28, 0x4A454EEF */ +P1 = 1.66666666666666019037e-01, /* 0x3FC55555, 0x5555553E */ +P2 = -2.77777777770155933842e-03, /* 0xBF66C16C, 0x16BEBD93 */ +P3 = 6.61375632143793436117e-05, /* 0x3F11566A, 0xAF25DE2C */ +P4 = -1.65339022054652515390e-06, /* 0xBEBBBD41, 0xC5D26BF1 */ +P5 = 4.13813679705723846039e-08, /* 0x3E663769, 0x72BEA4D0 */ +lg2 = 6.93147180559945286227e-01, /* 0x3FE62E42, 0xFEFA39EF */ +lg2_h = 6.93147182464599609375e-01, /* 0x3FE62E43, 0x00000000 */ +lg2_l = -1.90465429995776804525e-09, /* 0xBE205C61, 0x0CA86C39 */ +ovt = 8.0085662595372944372e-017, /* -(1024-log2(ovfl+.5ulp)) */ +cp = 9.61796693925975554329e-01, /* 0x3FEEC709, 0xDC3A03FD =2/(3ln2) */ +cp_h = 9.61796700954437255859e-01, /* 0x3FEEC709, 0xE0000000 =(float)cp */ +cp_l = -7.02846165095275826516e-09, /* 0xBE3E2FE0, 0x145B01F5 =tail of cp_h*/ +ivln2 = 1.44269504088896338700e+00, /* 0x3FF71547, 0x652B82FE =1/ln2 */ +ivln2_h = 1.44269502162933349609e+00, /* 0x3FF71547, 0x60000000 =24b 1/ln2*/ +ivln2_l = 1.92596299112661746887e-08; /* 0x3E54AE0B, 0xF85DDF44 =1/ln2 tail*/ + +double pow(double x, double y) +{ + double z,ax,z_h,z_l,p_h,p_l; + double y1,t1,t2,r,s,t,u,v,w; + int32_t i,j,k,yisint,n; + int32_t hx,hy,ix,iy; + uint32_t lx,ly; + + EXTRACT_WORDS(hx, lx, x); + EXTRACT_WORDS(hy, ly, y); + ix = hx & 0x7fffffff; + iy = hy & 0x7fffffff; + + /* x**0 = 1, even if x is NaN */ + if ((iy|ly) == 0) + return 1.0; + /* 1**y = 1, even if y is NaN */ + if (hx == 0x3ff00000 && lx == 0) + return 1.0; + /* NaN if either arg is NaN */ + if (ix > 0x7ff00000 || (ix == 0x7ff00000 && lx != 0) || + iy > 0x7ff00000 || (iy == 0x7ff00000 && ly != 0)) + return x + y; + + /* determine if y is an odd int when x < 0 + * yisint = 0 ... y is not an integer + * yisint = 1 ... y is an odd int + * yisint = 2 ... y is an even int + */ + yisint = 0; + if (hx < 0) { + if (iy >= 0x43400000) + yisint = 2; /* even integer y */ + else if (iy >= 0x3ff00000) { + k = (iy>>20) - 0x3ff; /* exponent */ + if (k > 20) { + uint32_t j = ly>>(52-k); + if ((j<<(52-k)) == ly) + yisint = 2 - (j&1); + } else if (ly == 0) { + uint32_t j = iy>>(20-k); + if ((j<<(20-k)) == iy) + yisint = 2 - (j&1); + } + } + } + + /* special value of y */ + if (ly == 0) { + if (iy == 0x7ff00000) { /* y is +-inf */ + if (((ix-0x3ff00000)|lx) == 0) /* (-1)**+-inf is 1 */ + return 1.0; + else if (ix >= 0x3ff00000) /* (|x|>1)**+-inf = inf,0 */ + return hy >= 0 ? y : 0.0; + else /* (|x|<1)**+-inf = 0,inf */ + return hy >= 0 ? 0.0 : -y; + } + if (iy == 0x3ff00000) { /* y is +-1 */ + if (hy >= 0) + return x; + y = 1/x; +#if FLT_EVAL_METHOD!=0 + { + union {double f; uint64_t i;} u = {y}; + uint64_t i = u.i & -1ULL/2; + if (i>>52 == 0 && (i&(i-1))) + FORCE_EVAL((float)y); + } +#endif + return y; + } + if (hy == 0x40000000) /* y is 2 */ + return x*x; + if (hy == 0x3fe00000) { /* y is 0.5 */ + if (hx >= 0) /* x >= +0 */ + return sqrt(x); + } + } + + ax = fabs(x); + /* special value of x */ + if (lx == 0) { + if (ix == 0x7ff00000 || ix == 0 || ix == 0x3ff00000) { /* x is +-0,+-inf,+-1 */ + z = ax; + if (hy < 0) /* z = (1/|x|) */ + z = 1.0/z; + if (hx < 0) { + if (((ix-0x3ff00000)|yisint) == 0) { + z = (z-z)/(z-z); /* (-1)**non-int is NaN */ + } else if (yisint == 1) + z = -z; /* (x<0)**odd = -(|x|**odd) */ + } + return z; + } + } + + s = 1.0; /* sign of result */ + if (hx < 0) { + if (yisint == 0) /* (x<0)**(non-int) is NaN */ + return (x-x)/(x-x); + if (yisint == 1) /* (x<0)**(odd int) */ + s = -1.0; + } + + /* |y| is huge */ + if (iy > 0x41e00000) { /* if |y| > 2**31 */ + if (iy > 0x43f00000) { /* if |y| > 2**64, must o/uflow */ + if (ix <= 0x3fefffff) + return hy < 0 ? huge*huge : tiny*tiny; + if (ix >= 0x3ff00000) + return hy > 0 ? huge*huge : tiny*tiny; + } + /* over/underflow if x is not close to one */ + if (ix < 0x3fefffff) + return hy < 0 ? s*huge*huge : s*tiny*tiny; + if (ix > 0x3ff00000) + return hy > 0 ? s*huge*huge : s*tiny*tiny; + /* now |1-x| is tiny <= 2**-20, suffice to compute + log(x) by x-x^2/2+x^3/3-x^4/4 */ + t = ax - 1.0; /* t has 20 trailing zeros */ + w = (t*t)*(0.5 - t*(0.3333333333333333333333-t*0.25)); + u = ivln2_h*t; /* ivln2_h has 21 sig. bits */ + v = t*ivln2_l - w*ivln2; + t1 = u + v; + SET_LOW_WORD(t1, 0); + t2 = v - (t1-u); + } else { + double ss,s2,s_h,s_l,t_h,t_l; + n = 0; + /* take care subnormal number */ + if (ix < 0x00100000) { + ax *= two53; + n -= 53; + GET_HIGH_WORD(ix,ax); + } + n += ((ix)>>20) - 0x3ff; + j = ix & 0x000fffff; + /* determine interval */ + ix = j | 0x3ff00000; /* normalize ix */ + if (j <= 0x3988E) /* |x|<sqrt(3/2) */ + k = 0; + else if (j < 0xBB67A) /* |x|<sqrt(3) */ + k = 1; + else { + k = 0; + n += 1; + ix -= 0x00100000; + } + SET_HIGH_WORD(ax, ix); + + /* compute ss = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */ + u = ax - bp[k]; /* bp[0]=1.0, bp[1]=1.5 */ + v = 1.0/(ax+bp[k]); + ss = u*v; + s_h = ss; + SET_LOW_WORD(s_h, 0); + /* t_h=ax+bp[k] High */ + t_h = 0.0; + SET_HIGH_WORD(t_h, ((ix>>1)|0x20000000) + 0x00080000 + (k<<18)); + t_l = ax - (t_h-bp[k]); + s_l = v*((u-s_h*t_h)-s_h*t_l); + /* compute log(ax) */ + s2 = ss*ss; + r = s2*s2*(L1+s2*(L2+s2*(L3+s2*(L4+s2*(L5+s2*L6))))); + r += s_l*(s_h+ss); + s2 = s_h*s_h; + t_h = 3.0 + s2 + r; + SET_LOW_WORD(t_h, 0); + t_l = r - ((t_h-3.0)-s2); + /* u+v = ss*(1+...) */ + u = s_h*t_h; + v = s_l*t_h + t_l*ss; + /* 2/(3log2)*(ss+...) */ + p_h = u + v; + SET_LOW_WORD(p_h, 0); + p_l = v - (p_h-u); + z_h = cp_h*p_h; /* cp_h+cp_l = 2/(3*log2) */ + z_l = cp_l*p_h+p_l*cp + dp_l[k]; + /* log2(ax) = (ss+..)*2/(3*log2) = n + dp_h + z_h + z_l */ + t = (double)n; + t1 = ((z_h + z_l) + dp_h[k]) + t; + SET_LOW_WORD(t1, 0); + t2 = z_l - (((t1 - t) - dp_h[k]) - z_h); + } + + /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */ + y1 = y; + SET_LOW_WORD(y1, 0); + p_l = (y-y1)*t1 + y*t2; + p_h = y1*t1; + z = p_l + p_h; + EXTRACT_WORDS(j, i, z); + if (j >= 0x40900000) { /* z >= 1024 */ + if (((j-0x40900000)|i) != 0) /* if z > 1024 */ + return s*huge*huge; /* overflow */ + if (p_l + ovt > z - p_h) + return s*huge*huge; /* overflow */ + } else if ((j&0x7fffffff) >= 0x4090cc00) { /* z <= -1075 */ // FIXME: instead of abs(j) use unsigned j + if (((j-0xc090cc00)|i) != 0) /* z < -1075 */ + return s*tiny*tiny; /* underflow */ + if (p_l <= z - p_h) + return s*tiny*tiny; /* underflow */ + } + /* + * compute 2**(p_h+p_l) + */ + i = j & 0x7fffffff; + k = (i>>20) - 0x3ff; + n = 0; + if (i > 0x3fe00000) { /* if |z| > 0.5, set n = [z+0.5] */ + n = j + (0x00100000>>(k+1)); + k = ((n&0x7fffffff)>>20) - 0x3ff; /* new k for n */ + t = 0.0; + SET_HIGH_WORD(t, n & ~(0x000fffff>>k)); + n = ((n&0x000fffff)|0x00100000)>>(20-k); + if (j < 0) + n = -n; + p_h -= t; + } + t = p_l + p_h; + SET_LOW_WORD(t, 0); + u = t*lg2_h; + v = (p_l-(t-p_h))*lg2 + t*lg2_l; + z = u + v; + w = v - (z-u); + t = z*z; + t1 = z - t*(P1+t*(P2+t*(P3+t*(P4+t*P5)))); + r = (z*t1)/(t1-2.0) - (w + z*w); + z = 1.0 - (r-z); + GET_HIGH_WORD(j, z); + j += n<<20; + if ((j>>20) <= 0) /* subnormal output */ + z = scalbn(z,n); + else + SET_HIGH_WORD(z, j); + return s*z; +} diff --git a/lib/libm_dbl/rint.c b/lib/libm_dbl/rint.c new file mode 100644 index 0000000000..fbba390e7d --- /dev/null +++ b/lib/libm_dbl/rint.c @@ -0,0 +1,28 @@ +#include <float.h> +#include <math.h> +#include <stdint.h> + +#if FLT_EVAL_METHOD==0 || FLT_EVAL_METHOD==1 +#define EPS DBL_EPSILON +#elif FLT_EVAL_METHOD==2 +#define EPS LDBL_EPSILON +#endif +static const double_t toint = 1/EPS; + +double rint(double x) +{ + union {double f; uint64_t i;} u = {x}; + int e = u.i>>52 & 0x7ff; + int s = u.i>>63; + double_t y; + + if (e >= 0x3ff+52) + return x; + if (s) + y = x - toint + toint; + else + y = x + toint - toint; + if (y == 0) + return s ? -0.0 : 0; + return y; +} diff --git a/lib/libm_dbl/scalbn.c b/lib/libm_dbl/scalbn.c new file mode 100644 index 0000000000..182f561068 --- /dev/null +++ b/lib/libm_dbl/scalbn.c @@ -0,0 +1,33 @@ +#include <math.h> +#include <stdint.h> + +double scalbn(double x, int n) +{ + union {double f; uint64_t i;} u; + double_t y = x; + + if (n > 1023) { + y *= 0x1p1023; + n -= 1023; + if (n > 1023) { + y *= 0x1p1023; + n -= 1023; + if (n > 1023) + n = 1023; + } + } else if (n < -1022) { + /* make sure final n < -53 to avoid double + rounding in the subnormal range */ + y *= 0x1p-1022 * 0x1p53; + n += 1022 - 53; + if (n < -1022) { + y *= 0x1p-1022 * 0x1p53; + n += 1022 - 53; + if (n < -1022) + n = -1022; + } + } + u.i = (uint64_t)(0x3ff+n)<<52; + x = y * u.f; + return x; +} diff --git a/lib/libm_dbl/sin.c b/lib/libm_dbl/sin.c new file mode 100644 index 0000000000..055e215bc8 --- /dev/null +++ b/lib/libm_dbl/sin.c @@ -0,0 +1,78 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_sin.c */ +/* + * ==================================================== + * 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. + * ==================================================== + */ +/* sin(x) + * Return sine function of x. + * + * kernel function: + * __sin ... sine function on [-pi/4,pi/4] + * __cos ... cose function on [-pi/4,pi/4] + * __rem_pio2 ... argument reduction routine + * + * Method. + * Let S,C and T denote the sin, cos and tan respectively on + * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2 + * in [-pi/4 , +pi/4], and let n = k mod 4. + * We have + * + * n sin(x) cos(x) tan(x) + * ---------------------------------------------------------- + * 0 S C T + * 1 C -S -1/T + * 2 -S -C T + * 3 -C S -1/T + * ---------------------------------------------------------- + * + * Special cases: + * Let trig be any of sin, cos, or tan. + * trig(+-INF) is NaN, with signals; + * trig(NaN) is that NaN; + * + * Accuracy: + * TRIG(x) returns trig(x) nearly rounded + */ + +#include "libm.h" + +double sin(double x) +{ + double y[2]; + uint32_t ix; + unsigned n; + + /* High word of x. */ + GET_HIGH_WORD(ix, x); + ix &= 0x7fffffff; + + /* |x| ~< pi/4 */ + if (ix <= 0x3fe921fb) { + if (ix < 0x3e500000) { /* |x| < 2**-26 */ + /* raise inexact if x != 0 and underflow if subnormal*/ + FORCE_EVAL(ix < 0x00100000 ? x/0x1p120f : x+0x1p120f); + return x; + } + return __sin(x, 0.0, 0); + } + + /* sin(Inf or NaN) is NaN */ + if (ix >= 0x7ff00000) + return x - x; + + /* argument reduction needed */ + n = __rem_pio2(x, y); + switch (n&3) { + case 0: return __sin(y[0], y[1], 1); + case 1: return __cos(y[0], y[1]); + case 2: return -__sin(y[0], y[1], 1); + default: + return -__cos(y[0], y[1]); + } +} diff --git a/lib/libm_dbl/sinh.c b/lib/libm_dbl/sinh.c new file mode 100644 index 0000000000..00022c4e6f --- /dev/null +++ b/lib/libm_dbl/sinh.c @@ -0,0 +1,39 @@ +#include "libm.h" + +/* sinh(x) = (exp(x) - 1/exp(x))/2 + * = (exp(x)-1 + (exp(x)-1)/exp(x))/2 + * = x + x^3/6 + o(x^5) + */ +double sinh(double x) +{ + union {double f; uint64_t i;} u = {.f = x}; + uint32_t w; + double t, h, absx; + + h = 0.5; + if (u.i >> 63) + h = -h; + /* |x| */ + u.i &= (uint64_t)-1/2; + absx = u.f; + w = u.i >> 32; + + /* |x| < log(DBL_MAX) */ + if (w < 0x40862e42) { + t = expm1(absx); + if (w < 0x3ff00000) { + if (w < 0x3ff00000 - (26<<20)) + /* note: inexact and underflow are raised by expm1 */ + /* note: this branch avoids spurious underflow */ + return x; + return h*(2*t - t*t/(t+1)); + } + /* note: |x|>log(0x1p26)+eps could be just h*exp(x) */ + return h*(t + t/(t+1)); + } + + /* |x| > log(DBL_MAX) or nan */ + /* note: the result is stored to handle overflow */ + t = 2*h*__expo2(absx); + return t; +} diff --git a/lib/libm_dbl/sqrt.c b/lib/libm_dbl/sqrt.c new file mode 100644 index 0000000000..b277567385 --- /dev/null +++ b/lib/libm_dbl/sqrt.c @@ -0,0 +1,185 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/e_sqrt.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. + * ==================================================== + */ +/* sqrt(x) + * Return correctly rounded sqrt. + * ------------------------------------------ + * | Use the hardware sqrt if you have one | + * ------------------------------------------ + * Method: + * Bit by bit method using integer arithmetic. (Slow, but portable) + * 1. Normalization + * Scale x to y in [1,4) with even powers of 2: + * find an integer k such that 1 <= (y=x*2^(2k)) < 4, then + * sqrt(x) = 2^k * sqrt(y) + * 2. Bit by bit computation + * Let q = sqrt(y) truncated to i bit after binary point (q = 1), + * i 0 + * i+1 2 + * s = 2*q , and y = 2 * ( y - q ). (1) + * i i i i + * + * To compute q from q , one checks whether + * i+1 i + * + * -(i+1) 2 + * (q + 2 ) <= y. (2) + * i + * -(i+1) + * If (2) is false, then q = q ; otherwise q = q + 2 . + * i+1 i i+1 i + * + * With some algebric manipulation, it is not difficult to see + * that (2) is equivalent to + * -(i+1) + * s + 2 <= y (3) + * i i + * + * The advantage of (3) is that s and y can be computed by + * i i + * the following recurrence formula: + * if (3) is false + * + * s = s , y = y ; (4) + * i+1 i i+1 i + * + * otherwise, + * -i -(i+1) + * s = s + 2 , y = y - s - 2 (5) + * i+1 i i+1 i i + * + * One may easily use induction to prove (4) and (5). + * Note. Since the left hand side of (3) contain only i+2 bits, + * it does not necessary to do a full (53-bit) comparison + * in (3). + * 3. Final rounding + * After generating the 53 bits result, we compute one more bit. + * Together with the remainder, we can decide whether the + * result is exact, bigger than 1/2ulp, or less than 1/2ulp + * (it will never equal to 1/2ulp). + * The rounding mode can be detected by checking whether + * huge + tiny is equal to huge, and whether huge - tiny is + * equal to huge for some floating point number "huge" and "tiny". + * + * Special cases: + * sqrt(+-0) = +-0 ... exact + * sqrt(inf) = inf + * sqrt(-ve) = NaN ... with invalid signal + * sqrt(NaN) = NaN ... with invalid signal for signaling NaN + */ + +#include "libm.h" + +static const double tiny = 1.0e-300; + +double sqrt(double x) +{ + double z; + int32_t sign = (int)0x80000000; + int32_t ix0,s0,q,m,t,i; + uint32_t r,t1,s1,ix1,q1; + + EXTRACT_WORDS(ix0, ix1, x); + + /* take care of Inf and NaN */ + if ((ix0&0x7ff00000) == 0x7ff00000) { + return x*x + x; /* sqrt(NaN)=NaN, sqrt(+inf)=+inf, sqrt(-inf)=sNaN */ + } + /* take care of zero */ + if (ix0 <= 0) { + if (((ix0&~sign)|ix1) == 0) + return x; /* sqrt(+-0) = +-0 */ + if (ix0 < 0) + return (x-x)/(x-x); /* sqrt(-ve) = sNaN */ + } + /* normalize x */ + m = ix0>>20; + if (m == 0) { /* subnormal x */ + while (ix0 == 0) { + m -= 21; + ix0 |= (ix1>>11); + ix1 <<= 21; + } + for (i=0; (ix0&0x00100000) == 0; i++) + ix0<<=1; + m -= i - 1; + ix0 |= ix1>>(32-i); + ix1 <<= i; + } + m -= 1023; /* unbias exponent */ + ix0 = (ix0&0x000fffff)|0x00100000; + if (m & 1) { /* odd m, double x to make it even */ + ix0 += ix0 + ((ix1&sign)>>31); + ix1 += ix1; + } + m >>= 1; /* m = [m/2] */ + + /* generate sqrt(x) bit by bit */ + ix0 += ix0 + ((ix1&sign)>>31); + ix1 += ix1; + q = q1 = s0 = s1 = 0; /* [q,q1] = sqrt(x) */ + r = 0x00200000; /* r = moving bit from right to left */ + + while (r != 0) { + t = s0 + r; + if (t <= ix0) { + s0 = t + r; + ix0 -= t; + q += r; + } + ix0 += ix0 + ((ix1&sign)>>31); + ix1 += ix1; + r >>= 1; + } + + r = sign; + while (r != 0) { + t1 = s1 + r; + t = s0; + if (t < ix0 || (t == ix0 && t1 <= ix1)) { + s1 = t1 + r; + if ((t1&sign) == sign && (s1&sign) == 0) + s0++; + ix0 -= t; + if (ix1 < t1) + ix0--; + ix1 -= t1; + q1 += r; + } + ix0 += ix0 + ((ix1&sign)>>31); + ix1 += ix1; + r >>= 1; + } + + /* use floating add to find out rounding direction */ + if ((ix0|ix1) != 0) { + z = 1.0 - tiny; /* raise inexact flag */ + if (z >= 1.0) { + z = 1.0 + tiny; + if (q1 == (uint32_t)0xffffffff) { + q1 = 0; + q++; + } else if (z > 1.0) { + if (q1 == (uint32_t)0xfffffffe) + q++; + q1 += 2; + } else + q1 += q1 & 1; + } + } + ix0 = (q>>1) + 0x3fe00000; + ix1 = q1>>1; + if (q&1) + ix1 |= sign; + ix0 += m << 20; + INSERT_WORDS(z, ix0, ix1); + return z; +} diff --git a/lib/libm_dbl/tan.c b/lib/libm_dbl/tan.c new file mode 100644 index 0000000000..9c724a45af --- /dev/null +++ b/lib/libm_dbl/tan.c @@ -0,0 +1,70 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_tan.c */ +/* + * ==================================================== + * 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. + * ==================================================== + */ +/* tan(x) + * Return tangent function of x. + * + * kernel function: + * __tan ... tangent function on [-pi/4,pi/4] + * __rem_pio2 ... argument reduction routine + * + * Method. + * Let S,C and T denote the sin, cos and tan respectively on + * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2 + * in [-pi/4 , +pi/4], and let n = k mod 4. + * We have + * + * n sin(x) cos(x) tan(x) + * ---------------------------------------------------------- + * 0 S C T + * 1 C -S -1/T + * 2 -S -C T + * 3 -C S -1/T + * ---------------------------------------------------------- + * + * Special cases: + * Let trig be any of sin, cos, or tan. + * trig(+-INF) is NaN, with signals; + * trig(NaN) is that NaN; + * + * Accuracy: + * TRIG(x) returns trig(x) nearly rounded + */ + +#include "libm.h" + +double tan(double x) +{ + double y[2]; + uint32_t ix; + unsigned n; + + GET_HIGH_WORD(ix, x); + ix &= 0x7fffffff; + + /* |x| ~< pi/4 */ + if (ix <= 0x3fe921fb) { + if (ix < 0x3e400000) { /* |x| < 2**-27 */ + /* raise inexact if x!=0 and underflow if subnormal */ + FORCE_EVAL(ix < 0x00100000 ? x/0x1p120f : x+0x1p120f); + return x; + } + return __tan(x, 0.0, 0); + } + + /* tan(Inf or NaN) is NaN */ + if (ix >= 0x7ff00000) + return x - x; + + /* argument reduction */ + n = __rem_pio2(x, y); + return __tan(y[0], y[1], n&1); +} diff --git a/lib/libm_dbl/tanh.c b/lib/libm_dbl/tanh.c new file mode 100644 index 0000000000..89743ba90f --- /dev/null +++ b/lib/libm_dbl/tanh.c @@ -0,0 +1,5 @@ +#include <math.h> + +double tanh(double x) { + return sinh(x) / cosh(x); +} diff --git a/lib/libm_dbl/tgamma.c b/lib/libm_dbl/tgamma.c new file mode 100644 index 0000000000..d1d0a04839 --- /dev/null +++ b/lib/libm_dbl/tgamma.c @@ -0,0 +1,222 @@ +/* +"A Precision Approximation of the Gamma Function" - Cornelius Lanczos (1964) +"Lanczos Implementation of the Gamma Function" - Paul Godfrey (2001) +"An Analysis of the Lanczos Gamma Approximation" - Glendon Ralph Pugh (2004) + +approximation method: + + (x - 0.5) S(x) +Gamma(x) = (x + g - 0.5) * ---------------- + exp(x + g - 0.5) + +with + a1 a2 a3 aN +S(x) ~= [ a0 + ----- + ----- + ----- + ... + ----- ] + x + 1 x + 2 x + 3 x + N + +with a0, a1, a2, a3,.. aN constants which depend on g. + +for x < 0 the following reflection formula is used: + +Gamma(x)*Gamma(-x) = -pi/(x sin(pi x)) + +most ideas and constants are from boost and python +*/ +#include "libm.h" + +static const double pi = 3.141592653589793238462643383279502884; + +/* sin(pi x) with x > 0x1p-100, if sin(pi*x)==0 the sign is arbitrary */ +static double sinpi(double x) +{ + int n; + + /* argument reduction: x = |x| mod 2 */ + /* spurious inexact when x is odd int */ + x = x * 0.5; + x = 2 * (x - floor(x)); + + /* reduce x into [-.25,.25] */ + n = 4 * x; + n = (n+1)/2; + x -= n * 0.5; + + x *= pi; + switch (n) { + default: /* case 4 */ + case 0: + return __sin(x, 0, 0); + case 1: + return __cos(x, 0); + case 2: + return __sin(-x, 0, 0); + case 3: + return -__cos(x, 0); + } +} + +#define N 12 +//static const double g = 6.024680040776729583740234375; +static const double gmhalf = 5.524680040776729583740234375; +static const double Snum[N+1] = { + 23531376880.410759688572007674451636754734846804940, + 42919803642.649098768957899047001988850926355848959, + 35711959237.355668049440185451547166705960488635843, + 17921034426.037209699919755754458931112671403265390, + 6039542586.3520280050642916443072979210699388420708, + 1439720407.3117216736632230727949123939715485786772, + 248874557.86205415651146038641322942321632125127801, + 31426415.585400194380614231628318205362874684987640, + 2876370.6289353724412254090516208496135991145378768, + 186056.26539522349504029498971604569928220784236328, + 8071.6720023658162106380029022722506138218516325024, + 210.82427775157934587250973392071336271166969580291, + 2.5066282746310002701649081771338373386264310793408, +}; +static const double Sden[N+1] = { + 0, 39916800, 120543840, 150917976, 105258076, 45995730, 13339535, + 2637558, 357423, 32670, 1925, 66, 1, +}; +/* n! for small integer n */ +static const double fact[] = { + 1, 1, 2, 6, 24, 120, 720, 5040.0, 40320.0, 362880.0, 3628800.0, 39916800.0, + 479001600.0, 6227020800.0, 87178291200.0, 1307674368000.0, 20922789888000.0, + 355687428096000.0, 6402373705728000.0, 121645100408832000.0, + 2432902008176640000.0, 51090942171709440000.0, 1124000727777607680000.0, +}; + +/* S(x) rational function for positive x */ +static double S(double x) +{ + double_t num = 0, den = 0; + int i; + + /* to avoid overflow handle large x differently */ + if (x < 8) + for (i = N; i >= 0; i--) { + num = num * x + Snum[i]; + den = den * x + Sden[i]; + } + else + for (i = 0; i <= N; i++) { + num = num / x + Snum[i]; + den = den / x + Sden[i]; + } + return num/den; +} + +double tgamma(double x) +{ + union {double f; uint64_t i;} u = {x}; + double absx, y; + double_t dy, z, r; + uint32_t ix = u.i>>32 & 0x7fffffff; + int sign = u.i>>63; + + /* special cases */ + if (ix >= 0x7ff00000) + /* tgamma(nan)=nan, tgamma(inf)=inf, tgamma(-inf)=nan with invalid */ + return x + INFINITY; + if (ix < (0x3ff-54)<<20) + /* |x| < 2^-54: tgamma(x) ~ 1/x, +-0 raises div-by-zero */ + return 1/x; + + /* integer arguments */ + /* raise inexact when non-integer */ + if (x == floor(x)) { + if (sign) + return 0/0.0; + if (x <= sizeof fact/sizeof *fact) + return fact[(int)x - 1]; + } + + /* x >= 172: tgamma(x)=inf with overflow */ + /* x =< -184: tgamma(x)=+-0 with underflow */ + if (ix >= 0x40670000) { /* |x| >= 184 */ + if (sign) { + FORCE_EVAL((float)(0x1p-126/x)); + if (floor(x) * 0.5 == floor(x * 0.5)) + return 0; + return -0.0; + } + x *= 0x1p1023; + return x; + } + + absx = sign ? -x : x; + + /* handle the error of x + g - 0.5 */ + y = absx + gmhalf; + if (absx > gmhalf) { + dy = y - absx; + dy -= gmhalf; + } else { + dy = y - gmhalf; + dy -= absx; + } + + z = absx - 0.5; + r = S(absx) * exp(-y); + if (x < 0) { + /* reflection formula for negative x */ + /* sinpi(absx) is not 0, integers are already handled */ + r = -pi / (sinpi(absx) * absx * r); + dy = -dy; + z = -z; + } + r += dy * (gmhalf+0.5) * r / y; + z = pow(y, 0.5*z); + y = r * z * z; + return y; +} + +#if 1 +double __lgamma_r(double x, int *sign) +{ + double r, absx; + + *sign = 1; + + /* special cases */ + if (!isfinite(x)) + /* lgamma(nan)=nan, lgamma(+-inf)=inf */ + return x*x; + + /* integer arguments */ + if (x == floor(x) && x <= 2) { + /* n <= 0: lgamma(n)=inf with divbyzero */ + /* n == 1,2: lgamma(n)=0 */ + if (x <= 0) + return 1/0.0; + return 0; + } + + absx = fabs(x); + + /* lgamma(x) ~ -log(|x|) for tiny |x| */ + if (absx < 0x1p-54) { + *sign = 1 - 2*!!signbit(x); + return -log(absx); + } + + /* use tgamma for smaller |x| */ + if (absx < 128) { + x = tgamma(x); + *sign = 1 - 2*!!signbit(x); + return log(fabs(x)); + } + + /* second term (log(S)-g) could be more precise here.. */ + /* or with stirling: (|x|-0.5)*(log(|x|)-1) + poly(1/|x|) */ + r = (absx-0.5)*(log(absx+gmhalf)-1) + (log(S(absx)) - (gmhalf+0.5)); + if (x < 0) { + /* reflection formula for negative x */ + x = sinpi(absx); + *sign = 2*!!signbit(x) - 1; + r = log(pi/(fabs(x)*absx)) - r; + } + return r; +} + +//weak_alias(__lgamma_r, lgamma_r); +#endif diff --git a/lib/libm_dbl/trunc.c b/lib/libm_dbl/trunc.c new file mode 100644 index 0000000000..d13711b501 --- /dev/null +++ b/lib/libm_dbl/trunc.c @@ -0,0 +1,19 @@ +#include "libm.h" + +double trunc(double x) +{ + union {double f; uint64_t i;} u = {x}; + int e = (int)(u.i >> 52 & 0x7ff) - 0x3ff + 12; + uint64_t m; + + if (e >= 52 + 12) + return x; + if (e < 12) + e = 1; + m = -1ULL >> e; + if ((u.i & m) == 0) + return x; + FORCE_EVAL(x + 0x1p120f); + u.i &= ~m; + return u.f; +} |