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diff --git a/lib/mlibc/options/ansi/musl-generic-math/powl.c b/lib/mlibc/options/ansi/musl-generic-math/powl.c
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@@ -1,522 +0,0 @@
-/* origin: OpenBSD /usr/src/lib/libm/src/ld80/e_powl.c */
-/*
- * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net>
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-/* powl.c
- *
- * Power function, long double precision
- *
- *
- * SYNOPSIS:
- *
- * long double x, y, z, powl();
- *
- * z = powl( x, y );
- *
- *
- * DESCRIPTION:
- *
- * Computes x raised to the yth power. Analytically,
- *
- * x**y = exp( y log(x) ).
- *
- * Following Cody and Waite, this program uses a lookup table
- * of 2**-i/32 and pseudo extended precision arithmetic to
- * obtain several extra bits of accuracy in both the logarithm
- * and the exponential.
- *
- *
- * ACCURACY:
- *
- * The relative error of pow(x,y) can be estimated
- * by y dl ln(2), where dl is the absolute error of
- * the internally computed base 2 logarithm. At the ends
- * of the approximation interval the logarithm equal 1/32
- * and its relative error is about 1 lsb = 1.1e-19. Hence
- * the predicted relative error in the result is 2.3e-21 y .
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- *
- * IEEE +-1000 40000 2.8e-18 3.7e-19
- * .001 < x < 1000, with log(x) uniformly distributed.
- * -1000 < y < 1000, y uniformly distributed.
- *
- * IEEE 0,8700 60000 6.5e-18 1.0e-18
- * 0.99 < x < 1.01, 0 < y < 8700, uniformly distributed.
- *
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * pow overflow x**y > MAXNUM INFINITY
- * pow underflow x**y < 1/MAXNUM 0.0
- * pow domain x<0 and y noninteger 0.0
- *
- */
-
-#include "libm.h"
-
-#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
-long double powl(long double x, long double y)
-{
- return pow(x, y);
-}
-#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
-
-/* Table size */
-#define NXT 32
-
-/* log(1+x) = x - .5x^2 + x^3 * P(z)/Q(z)
- * on the domain 2^(-1/32) - 1 <= x <= 2^(1/32) - 1
- */
-static const long double P[] = {
- 8.3319510773868690346226E-4L,
- 4.9000050881978028599627E-1L,
- 1.7500123722550302671919E0L,
- 1.4000100839971580279335E0L,
-};
-static const long double Q[] = {
-/* 1.0000000000000000000000E0L,*/
- 5.2500282295834889175431E0L,
- 8.4000598057587009834666E0L,
- 4.2000302519914740834728E0L,
-};
-/* A[i] = 2^(-i/32), rounded to IEEE long double precision.
- * If i is even, A[i] + B[i/2] gives additional accuracy.
- */
-static const long double A[33] = {
- 1.0000000000000000000000E0L,
- 9.7857206208770013448287E-1L,
- 9.5760328069857364691013E-1L,
- 9.3708381705514995065011E-1L,
- 9.1700404320467123175367E-1L,
- 8.9735453750155359320742E-1L,
- 8.7812608018664974155474E-1L,
- 8.5930964906123895780165E-1L,
- 8.4089641525371454301892E-1L,
- 8.2287773907698242225554E-1L,
- 8.0524516597462715409607E-1L,
- 7.8799042255394324325455E-1L,
- 7.7110541270397041179298E-1L,
- 7.5458221379671136985669E-1L,
- 7.3841307296974965571198E-1L,
- 7.2259040348852331001267E-1L,
- 7.0710678118654752438189E-1L,
- 6.9195494098191597746178E-1L,
- 6.7712777346844636413344E-1L,
- 6.6261832157987064729696E-1L,
- 6.4841977732550483296079E-1L,
- 6.3452547859586661129850E-1L,
- 6.2092890603674202431705E-1L,
- 6.0762367999023443907803E-1L,
- 5.9460355750136053334378E-1L,
- 5.8186242938878875689693E-1L,
- 5.6939431737834582684856E-1L,
- 5.5719337129794626814472E-1L,
- 5.4525386633262882960438E-1L,
- 5.3357020033841180906486E-1L,
- 5.2213689121370692017331E-1L,
- 5.1094857432705833910408E-1L,
- 5.0000000000000000000000E-1L,
-};
-static const long double B[17] = {
- 0.0000000000000000000000E0L,
- 2.6176170809902549338711E-20L,
--1.0126791927256478897086E-20L,
- 1.3438228172316276937655E-21L,
- 1.2207982955417546912101E-20L,
--6.3084814358060867200133E-21L,
- 1.3164426894366316434230E-20L,
--1.8527916071632873716786E-20L,
- 1.8950325588932570796551E-20L,
- 1.5564775779538780478155E-20L,
- 6.0859793637556860974380E-21L,
--2.0208749253662532228949E-20L,
- 1.4966292219224761844552E-20L,
- 3.3540909728056476875639E-21L,
--8.6987564101742849540743E-22L,
--1.2327176863327626135542E-20L,
- 0.0000000000000000000000E0L,
-};
-
-/* 2^x = 1 + x P(x),
- * on the interval -1/32 <= x <= 0
- */
-static const long double R[] = {
- 1.5089970579127659901157E-5L,
- 1.5402715328927013076125E-4L,
- 1.3333556028915671091390E-3L,
- 9.6181291046036762031786E-3L,
- 5.5504108664798463044015E-2L,
- 2.4022650695910062854352E-1L,
- 6.9314718055994530931447E-1L,
-};
-
-#define MEXP (NXT*16384.0L)
-/* The following if denormal numbers are supported, else -MEXP: */
-#define MNEXP (-NXT*(16384.0L+64.0L))
-/* log2(e) - 1 */
-#define LOG2EA 0.44269504088896340735992L
-
-#define F W
-#define Fa Wa
-#define Fb Wb
-#define G W
-#define Ga Wa
-#define Gb u
-#define H W
-#define Ha Wb
-#define Hb Wb
-
-static const long double MAXLOGL = 1.1356523406294143949492E4L;
-static const long double MINLOGL = -1.13994985314888605586758E4L;
-static const long double LOGE2L = 6.9314718055994530941723E-1L;
-static const long double huge = 0x1p10000L;
-/* XXX Prevent gcc from erroneously constant folding this. */
-static const volatile long double twom10000 = 0x1p-10000L;
-
-static long double reducl(long double);
-static long double powil(long double, int);
-
-long double powl(long double x, long double y)
-{
- /* double F, Fa, Fb, G, Ga, Gb, H, Ha, Hb */
- int i, nflg, iyflg, yoddint;
- long e;
- volatile long double z=0;
- long double w=0, W=0, Wa=0, Wb=0, ya=0, yb=0, u=0;
-
- /* make sure no invalid exception is raised by nan comparision */
- if (isnan(x)) {
- if (!isnan(y) && y == 0.0)
- return 1.0;
- return x;
- }
- if (isnan(y)) {
- if (x == 1.0)
- return 1.0;
- return y;
- }
- if (x == 1.0)
- return 1.0; /* 1**y = 1, even if y is nan */
- if (x == -1.0 && !isfinite(y))
- return 1.0; /* -1**inf = 1 */
- if (y == 0.0)
- return 1.0; /* x**0 = 1, even if x is nan */
- if (y == 1.0)
- return x;
- if (y >= LDBL_MAX) {
- if (x > 1.0 || x < -1.0)
- return INFINITY;
- if (x != 0.0)
- return 0.0;
- }
- if (y <= -LDBL_MAX) {
- if (x > 1.0 || x < -1.0)
- return 0.0;
- if (x != 0.0 || y == -INFINITY)
- return INFINITY;
- }
- if (x >= LDBL_MAX) {
- if (y > 0.0)
- return INFINITY;
- return 0.0;
- }
-
- w = floorl(y);
-
- /* Set iyflg to 1 if y is an integer. */
- iyflg = 0;
- if (w == y)
- iyflg = 1;
-
- /* Test for odd integer y. */
- yoddint = 0;
- if (iyflg) {
- ya = fabsl(y);
- ya = floorl(0.5 * ya);
- yb = 0.5 * fabsl(w);
- if( ya != yb )
- yoddint = 1;
- }
-
- if (x <= -LDBL_MAX) {
- if (y > 0.0) {
- if (yoddint)
- return -INFINITY;
- return INFINITY;
- }
- if (y < 0.0) {
- if (yoddint)
- return -0.0;
- return 0.0;
- }
- }
- nflg = 0; /* (x<0)**(odd int) */
- if (x <= 0.0) {
- if (x == 0.0) {
- if (y < 0.0) {
- if (signbit(x) && yoddint)
- /* (-0.0)**(-odd int) = -inf, divbyzero */
- return -1.0/0.0;
- /* (+-0.0)**(negative) = inf, divbyzero */
- return 1.0/0.0;
- }
- if (signbit(x) && yoddint)
- return -0.0;
- return 0.0;
- }
- if (iyflg == 0)
- return (x - x) / (x - x); /* (x<0)**(non-int) is NaN */
- /* (x<0)**(integer) */
- if (yoddint)
- nflg = 1; /* negate result */
- x = -x;
- }
- /* (+integer)**(integer) */
- if (iyflg && floorl(x) == x && fabsl(y) < 32768.0) {
- w = powil(x, (int)y);
- return nflg ? -w : w;
- }
-
- /* separate significand from exponent */
- x = frexpl(x, &i);
- e = i;
-
- /* find significand in antilog table A[] */
- i = 1;
- if (x <= A[17])
- i = 17;
- if (x <= A[i+8])
- i += 8;
- if (x <= A[i+4])
- i += 4;
- if (x <= A[i+2])
- i += 2;
- if (x >= A[1])
- i = -1;
- i += 1;
-
- /* Find (x - A[i])/A[i]
- * in order to compute log(x/A[i]):
- *
- * log(x) = log( a x/a ) = log(a) + log(x/a)
- *
- * log(x/a) = log(1+v), v = x/a - 1 = (x-a)/a
- */
- x -= A[i];
- x -= B[i/2];
- x /= A[i];
-
- /* rational approximation for log(1+v):
- *
- * log(1+v) = v - v**2/2 + v**3 P(v) / Q(v)
- */
- z = x*x;
- w = x * (z * __polevll(x, P, 3) / __p1evll(x, Q, 3));
- w = w - 0.5*z;
-
- /* Convert to base 2 logarithm:
- * multiply by log2(e) = 1 + LOG2EA
- */
- z = LOG2EA * w;
- z += w;
- z += LOG2EA * x;
- z += x;
-
- /* Compute exponent term of the base 2 logarithm. */
- w = -i;
- w /= NXT;
- w += e;
- /* Now base 2 log of x is w + z. */
-
- /* Multiply base 2 log by y, in extended precision. */
-
- /* separate y into large part ya
- * and small part yb less than 1/NXT
- */
- ya = reducl(y);
- yb = y - ya;
-
- /* (w+z)(ya+yb)
- * = w*ya + w*yb + z*y
- */
- F = z * y + w * yb;
- Fa = reducl(F);
- Fb = F - Fa;
-
- G = Fa + w * ya;
- Ga = reducl(G);
- Gb = G - Ga;
-
- H = Fb + Gb;
- Ha = reducl(H);
- w = (Ga + Ha) * NXT;
-
- /* Test the power of 2 for overflow */
- if (w > MEXP)
- return huge * huge; /* overflow */
- if (w < MNEXP)
- return twom10000 * twom10000; /* underflow */
-
- e = w;
- Hb = H - Ha;
-
- if (Hb > 0.0) {
- e += 1;
- Hb -= 1.0/NXT; /*0.0625L;*/
- }
-
- /* Now the product y * log2(x) = Hb + e/NXT.
- *
- * Compute base 2 exponential of Hb,
- * where -0.0625 <= Hb <= 0.
- */
- z = Hb * __polevll(Hb, R, 6); /* z = 2**Hb - 1 */
-
- /* Express e/NXT as an integer plus a negative number of (1/NXT)ths.
- * Find lookup table entry for the fractional power of 2.
- */
- if (e < 0)
- i = 0;
- else
- i = 1;
- i = e/NXT + i;
- e = NXT*i - e;
- w = A[e];
- z = w * z; /* 2**-e * ( 1 + (2**Hb-1) ) */
- z = z + w;
- z = scalbnl(z, i); /* multiply by integer power of 2 */
-
- if (nflg)
- z = -z;
- return z;
-}
-
-
-/* Find a multiple of 1/NXT that is within 1/NXT of x. */
-static long double reducl(long double x)
-{
- long double t;
-
- t = x * NXT;
- t = floorl(t);
- t = t / NXT;
- return t;
-}
-
-/*
- * Positive real raised to integer power, long double precision
- *
- *
- * SYNOPSIS:
- *
- * long double x, y, powil();
- * int n;
- *
- * y = powil( x, n );
- *
- *
- * DESCRIPTION:
- *
- * Returns argument x>0 raised to the nth power.
- * The routine efficiently decomposes n as a sum of powers of
- * two. The desired power is a product of two-to-the-kth
- * powers of x. Thus to compute the 32767 power of x requires
- * 28 multiplications instead of 32767 multiplications.
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic x domain n domain # trials peak rms
- * IEEE .001,1000 -1022,1023 50000 4.3e-17 7.8e-18
- * IEEE 1,2 -1022,1023 20000 3.9e-17 7.6e-18
- * IEEE .99,1.01 0,8700 10000 3.6e-16 7.2e-17
- *
- * Returns MAXNUM on overflow, zero on underflow.
- */
-
-static long double powil(long double x, int nn)
-{
- long double ww, y;
- long double s;
- int n, e, sign, lx;
-
- if (nn == 0)
- return 1.0;
-
- if (nn < 0) {
- sign = -1;
- n = -nn;
- } else {
- sign = 1;
- n = nn;
- }
-
- /* Overflow detection */
-
- /* Calculate approximate logarithm of answer */
- s = x;
- s = frexpl( s, &lx);
- e = (lx - 1)*n;
- if ((e == 0) || (e > 64) || (e < -64)) {
- s = (s - 7.0710678118654752e-1L) / (s + 7.0710678118654752e-1L);
- s = (2.9142135623730950L * s - 0.5 + lx) * nn * LOGE2L;
- } else {
- s = LOGE2L * e;
- }
-
- if (s > MAXLOGL)
- return huge * huge; /* overflow */
-
- if (s < MINLOGL)
- return twom10000 * twom10000; /* underflow */
- /* Handle tiny denormal answer, but with less accuracy
- * since roundoff error in 1.0/x will be amplified.
- * The precise demarcation should be the gradual underflow threshold.
- */
- if (s < -MAXLOGL+2.0) {
- x = 1.0/x;
- sign = -sign;
- }
-
- /* First bit of the power */
- if (n & 1)
- y = x;
- else
- y = 1.0;
-
- ww = x;
- n >>= 1;
- while (n) {
- ww = ww * ww; /* arg to the 2-to-the-kth power */
- if (n & 1) /* if that bit is set, then include in product */
- y *= ww;
- n >>= 1;
- }
-
- if (sign < 0)
- y = 1.0/y;
- return y;
-}
-#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
-// TODO: broken implementation to make things compile
-long double powl(long double x, long double y)
-{
- return pow(x, y);
-}
-#endif
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