lib: Add libm_dbl, a double-precision math library, from musl-1.1.16.
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This directory contains source code for the standard double-precision math
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functions.
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The files lgamma.c, log10.c and tanh.c are too small to have a meaningful
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copyright or license.
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The rest of the files in this directory are copied from the musl library,
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v1.1.16, and, unless otherwise stated in the individual file, have the
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following copyright and MIT license:
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----------------------------------------------------------------------
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Copyright © 2005-2014 Rich Felker, et al.
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Permission is hereby granted, free of charge, to any person obtaining
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a copy of this software and associated documentation files (the
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"Software"), to deal in the Software without restriction, including
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without limitation the rights to use, copy, modify, merge, publish,
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distribute, sublicense, and/or sell copies of the Software, and to
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permit persons to whom the Software is furnished to do so, subject to
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the following conditions:
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The above copyright notice and this permission notice shall be
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included in all copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
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CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
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TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
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SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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----------------------------------------------------------------------
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/* origin: FreeBSD /usr/src/lib/msun/src/k_cos.c */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunSoft, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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/*
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* __cos( x, y )
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* kernel cos function on [-pi/4, pi/4], pi/4 ~ 0.785398164
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* Input x is assumed to be bounded by ~pi/4 in magnitude.
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* Input y is the tail of x.
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*
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* Algorithm
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* 1. Since cos(-x) = cos(x), we need only to consider positive x.
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* 2. if x < 2^-27 (hx<0x3e400000 0), return 1 with inexact if x!=0.
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* 3. cos(x) is approximated by a polynomial of degree 14 on
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* [0,pi/4]
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* 4 14
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* cos(x) ~ 1 - x*x/2 + C1*x + ... + C6*x
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* where the remez error is
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*
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* | 2 4 6 8 10 12 14 | -58
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* |cos(x)-(1-.5*x +C1*x +C2*x +C3*x +C4*x +C5*x +C6*x )| <= 2
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* | |
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*
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* 4 6 8 10 12 14
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* 4. let r = C1*x +C2*x +C3*x +C4*x +C5*x +C6*x , then
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* cos(x) ~ 1 - x*x/2 + r
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* since cos(x+y) ~ cos(x) - sin(x)*y
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* ~ cos(x) - x*y,
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* a correction term is necessary in cos(x) and hence
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* cos(x+y) = 1 - (x*x/2 - (r - x*y))
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* For better accuracy, rearrange to
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* cos(x+y) ~ w + (tmp + (r-x*y))
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* where w = 1 - x*x/2 and tmp is a tiny correction term
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* (1 - x*x/2 == w + tmp exactly in infinite precision).
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* The exactness of w + tmp in infinite precision depends on w
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* and tmp having the same precision as x. If they have extra
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* precision due to compiler bugs, then the extra precision is
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* only good provided it is retained in all terms of the final
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* expression for cos(). Retention happens in all cases tested
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* under FreeBSD, so don't pessimize things by forcibly clipping
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* any extra precision in w.
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*/
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#include "libm.h"
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static const double
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C1 = 4.16666666666666019037e-02, /* 0x3FA55555, 0x5555554C */
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C2 = -1.38888888888741095749e-03, /* 0xBF56C16C, 0x16C15177 */
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C3 = 2.48015872894767294178e-05, /* 0x3EFA01A0, 0x19CB1590 */
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C4 = -2.75573143513906633035e-07, /* 0xBE927E4F, 0x809C52AD */
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C5 = 2.08757232129817482790e-09, /* 0x3E21EE9E, 0xBDB4B1C4 */
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C6 = -1.13596475577881948265e-11; /* 0xBDA8FAE9, 0xBE8838D4 */
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double __cos(double x, double y)
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{
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double_t hz,z,r,w;
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z = x*x;
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w = z*z;
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r = z*(C1+z*(C2+z*C3)) + w*w*(C4+z*(C5+z*C6));
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hz = 0.5*z;
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w = 1.0-hz;
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return w + (((1.0-w)-hz) + (z*r-x*y));
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}
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#include "libm.h"
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/* k is such that k*ln2 has minimal relative error and x - kln2 > log(DBL_MIN) */
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static const int k = 2043;
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static const double kln2 = 0x1.62066151add8bp+10;
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/* exp(x)/2 for x >= log(DBL_MAX), slightly better than 0.5*exp(x/2)*exp(x/2) */
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double __expo2(double x)
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{
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double scale;
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/* note that k is odd and scale*scale overflows */
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INSERT_WORDS(scale, (uint32_t)(0x3ff + k/2) << 20, 0);
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/* exp(x - k ln2) * 2**(k-1) */
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return exp(x - kln2) * scale * scale;
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}
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#include <math.h>
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#include <stdint.h>
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int __fpclassifyd(double x)
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{
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union {double f; uint64_t i;} u = {x};
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int e = u.i>>52 & 0x7ff;
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if (!e) return u.i<<1 ? FP_SUBNORMAL : FP_ZERO;
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if (e==0x7ff) return u.i<<12 ? FP_NAN : FP_INFINITE;
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return FP_NORMAL;
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}
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/* origin: FreeBSD /usr/src/lib/msun/src/e_rem_pio2.c */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunSoft, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*
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* Optimized by Bruce D. Evans.
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*/
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/* __rem_pio2(x,y)
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*
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* return the remainder of x rem pi/2 in y[0]+y[1]
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* use __rem_pio2_large() for large x
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*/
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#include "libm.h"
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#if FLT_EVAL_METHOD==0 || FLT_EVAL_METHOD==1
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#define EPS DBL_EPSILON
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#elif FLT_EVAL_METHOD==2
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#define EPS LDBL_EPSILON
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#endif
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/*
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* invpio2: 53 bits of 2/pi
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* pio2_1: first 33 bit of pi/2
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* pio2_1t: pi/2 - pio2_1
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* pio2_2: second 33 bit of pi/2
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* pio2_2t: pi/2 - (pio2_1+pio2_2)
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* pio2_3: third 33 bit of pi/2
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* pio2_3t: pi/2 - (pio2_1+pio2_2+pio2_3)
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*/
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static const double
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toint = 1.5/EPS,
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invpio2 = 6.36619772367581382433e-01, /* 0x3FE45F30, 0x6DC9C883 */
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pio2_1 = 1.57079632673412561417e+00, /* 0x3FF921FB, 0x54400000 */
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pio2_1t = 6.07710050650619224932e-11, /* 0x3DD0B461, 0x1A626331 */
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pio2_2 = 6.07710050630396597660e-11, /* 0x3DD0B461, 0x1A600000 */
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pio2_2t = 2.02226624879595063154e-21, /* 0x3BA3198A, 0x2E037073 */
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pio2_3 = 2.02226624871116645580e-21, /* 0x3BA3198A, 0x2E000000 */
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pio2_3t = 8.47842766036889956997e-32; /* 0x397B839A, 0x252049C1 */
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/* caller must handle the case when reduction is not needed: |x| ~<= pi/4 */
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int __rem_pio2(double x, double *y)
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{
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union {double f; uint64_t i;} u = {x};
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double_t z,w,t,r,fn;
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double tx[3],ty[2];
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uint32_t ix;
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int sign, n, ex, ey, i;
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sign = u.i>>63;
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ix = u.i>>32 & 0x7fffffff;
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if (ix <= 0x400f6a7a) { /* |x| ~<= 5pi/4 */
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if ((ix & 0xfffff) == 0x921fb) /* |x| ~= pi/2 or 2pi/2 */
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goto medium; /* cancellation -- use medium case */
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if (ix <= 0x4002d97c) { /* |x| ~<= 3pi/4 */
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if (!sign) {
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z = x - pio2_1; /* one round good to 85 bits */
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y[0] = z - pio2_1t;
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y[1] = (z-y[0]) - pio2_1t;
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return 1;
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} else {
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z = x + pio2_1;
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y[0] = z + pio2_1t;
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y[1] = (z-y[0]) + pio2_1t;
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return -1;
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}
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} else {
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if (!sign) {
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z = x - 2*pio2_1;
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y[0] = z - 2*pio2_1t;
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y[1] = (z-y[0]) - 2*pio2_1t;
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return 2;
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} else {
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z = x + 2*pio2_1;
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y[0] = z + 2*pio2_1t;
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y[1] = (z-y[0]) + 2*pio2_1t;
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return -2;
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}
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}
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}
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if (ix <= 0x401c463b) { /* |x| ~<= 9pi/4 */
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if (ix <= 0x4015fdbc) { /* |x| ~<= 7pi/4 */
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if (ix == 0x4012d97c) /* |x| ~= 3pi/2 */
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goto medium;
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if (!sign) {
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z = x - 3*pio2_1;
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y[0] = z - 3*pio2_1t;
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y[1] = (z-y[0]) - 3*pio2_1t;
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return 3;
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} else {
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z = x + 3*pio2_1;
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y[0] = z + 3*pio2_1t;
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y[1] = (z-y[0]) + 3*pio2_1t;
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return -3;
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}
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} else {
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if (ix == 0x401921fb) /* |x| ~= 4pi/2 */
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goto medium;
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if (!sign) {
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z = x - 4*pio2_1;
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y[0] = z - 4*pio2_1t;
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y[1] = (z-y[0]) - 4*pio2_1t;
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return 4;
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} else {
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z = x + 4*pio2_1;
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y[0] = z + 4*pio2_1t;
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y[1] = (z-y[0]) + 4*pio2_1t;
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return -4;
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}
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}
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}
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if (ix < 0x413921fb) { /* |x| ~< 2^20*(pi/2), medium size */
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medium:
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/* rint(x/(pi/2)), Assume round-to-nearest. */
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fn = (double_t)x*invpio2 + toint - toint;
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n = (int32_t)fn;
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r = x - fn*pio2_1;
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w = fn*pio2_1t; /* 1st round, good to 85 bits */
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y[0] = r - w;
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u.f = y[0];
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ey = u.i>>52 & 0x7ff;
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ex = ix>>20;
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if (ex - ey > 16) { /* 2nd round, good to 118 bits */
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t = r;
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w = fn*pio2_2;
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r = t - w;
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w = fn*pio2_2t - ((t-r)-w);
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y[0] = r - w;
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u.f = y[0];
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ey = u.i>>52 & 0x7ff;
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if (ex - ey > 49) { /* 3rd round, good to 151 bits, covers all cases */
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t = r;
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w = fn*pio2_3;
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r = t - w;
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w = fn*pio2_3t - ((t-r)-w);
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y[0] = r - w;
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}
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}
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y[1] = (r - y[0]) - w;
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return n;
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}
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/*
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* all other (large) arguments
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*/
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if (ix >= 0x7ff00000) { /* x is inf or NaN */
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y[0] = y[1] = x - x;
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return 0;
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}
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/* set z = scalbn(|x|,-ilogb(x)+23) */
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u.f = x;
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u.i &= (uint64_t)-1>>12;
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u.i |= (uint64_t)(0x3ff + 23)<<52;
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z = u.f;
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for (i=0; i < 2; i++) {
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tx[i] = (double)(int32_t)z;
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z = (z-tx[i])*0x1p24;
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}
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tx[i] = z;
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/* skip zero terms, first term is non-zero */
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while (tx[i] == 0.0)
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i--;
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n = __rem_pio2_large(tx,ty,(int)(ix>>20)-(0x3ff+23),i+1,1);
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if (sign) {
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y[0] = -ty[0];
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y[1] = -ty[1];
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return -n;
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}
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y[0] = ty[0];
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y[1] = ty[1];
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return n;
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}
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/* origin: FreeBSD /usr/src/lib/msun/src/k_rem_pio2.c */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunSoft, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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/*
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* __rem_pio2_large(x,y,e0,nx,prec)
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* double x[],y[]; int e0,nx,prec;
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*
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* __rem_pio2_large return the last three digits of N with
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* y = x - N*pi/2
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* so that |y| < pi/2.
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*
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* The method is to compute the integer (mod 8) and fraction parts of
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* (2/pi)*x without doing the full multiplication. In general we
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* skip the part of the product that are known to be a huge integer (
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* more accurately, = 0 mod 8 ). Thus the number of operations are
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* independent of the exponent of the input.
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*
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* (2/pi) is represented by an array of 24-bit integers in ipio2[].
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*
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* Input parameters:
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* x[] The input value (must be positive) is broken into nx
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* pieces of 24-bit integers in double precision format.
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* x[i] will be the i-th 24 bit of x. The scaled exponent
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* of x[0] is given in input parameter e0 (i.e., x[0]*2^e0
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* match x's up to 24 bits.
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*
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* Example of breaking a double positive z into x[0]+x[1]+x[2]:
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* e0 = ilogb(z)-23
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* z = scalbn(z,-e0)
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* for i = 0,1,2
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* x[i] = floor(z)
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* z = (z-x[i])*2**24
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*
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*
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* y[] ouput result in an array of double precision numbers.
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* The dimension of y[] is:
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* 24-bit precision 1
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* 53-bit precision 2
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* 64-bit precision 2
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* 113-bit precision 3
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* The actual value is the sum of them. Thus for 113-bit
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* precison, one may have to do something like:
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*
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* long double t,w,r_head, r_tail;
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* t = (long double)y[2] + (long double)y[1];
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* w = (long double)y[0];
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* r_head = t+w;
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* r_tail = w - (r_head - t);
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*
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* e0 The exponent of x[0]. Must be <= 16360 or you need to
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* expand the ipio2 table.
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*
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* nx dimension of x[]
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*
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* prec an integer indicating the precision:
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* 0 24 bits (single)
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* 1 53 bits (double)
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* 2 64 bits (extended)
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* 3 113 bits (quad)
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*
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* External function:
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* double scalbn(), floor();
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*
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*
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* Here is the description of some local variables:
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*
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* jk jk+1 is the initial number of terms of ipio2[] needed
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* in the computation. The minimum and recommended value
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* for jk is 3,4,4,6 for single, double, extended, and quad.
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* jk+1 must be 2 larger than you might expect so that our
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* recomputation test works. (Up to 24 bits in the integer
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* part (the 24 bits of it that we compute) and 23 bits in
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* the fraction part may be lost to cancelation before we
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* recompute.)
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*
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* jz local integer variable indicating the number of
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* terms of ipio2[] used.
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*
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* jx nx - 1
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*
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* jv index for pointing to the suitable ipio2[] for the
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* computation. In general, we want
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* ( 2^e0*x[0] * ipio2[jv-1]*2^(-24jv) )/8
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* is an integer. Thus
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* e0-3-24*jv >= 0 or (e0-3)/24 >= jv
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* Hence jv = max(0,(e0-3)/24).
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*
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||||
* 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;
|
||||
}
|
@ -0,0 +1,12 @@
|
||||
#include "libm.h"
|
||||
|
||||
int __signbitd(double x)
|
||||
{
|
||||
union {
|
||||
double d;
|
||||
uint64_t i;
|
||||
} y = { x };
|
||||
return y.i>>63;
|
||||
}
|
||||
|
||||
|
@ -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);
|
||||
}
|
@ -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);
|
||||
}
|
@ -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);
|
||||
}
|
@ -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;
|
||||
}
|
@ -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;
|
||||
}
|
@ -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;
|
||||
}
|
@ -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;
|
||||
}
|
@ -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) |