msun: add ld80/ld128 powl, cpow, cpowf, cpowl from openbsd

This corresponds to the latest status (hasn't changed in 9+
years) from openbsd of ld80/ld128 powl, and source cpowf, cpow,
cpowl (the complex power functions for float complex, double
complex, and long double complex) which are required for C99
compliance and were missing from FreeBSD. Also required for
some numerical codes using complex numbered Hamiltonians.

Thanks to jhb for tracking down the issue with making
weak_reference compile on powerpc.

When asked to review, bde said "I don't like it" - but
provided no actionable feedback or superior implementations.

Discussed with: jhb
Submitted by: jmd
Differential Revision: https://reviews.freebsd.org/D15919
This commit is contained in:
Matt Macy 2018-07-15 00:23:10 +00:00
parent c8b1bdc31c
commit 6813d08ff5
14 changed files with 1511 additions and 16 deletions

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@ -109,6 +109,10 @@ double complex conj(double complex) __pure2;
float complex conjf(float complex) __pure2;
long double complex
conjl(long double complex) __pure2;
float complex cpowf(float complex, float complex);
double complex cpow(double complex, double complex);
long double complex
cpowl(long double complex, long double complex);
float complex cprojf(float complex) __pure2;
double complex cproj(double complex) __pure2;
long double complex

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@ -56,6 +56,7 @@ COMMON_SRCS= b_exp.c b_log.c b_tgamma.c \
imprecise.c \
k_cos.c k_cosf.c k_exp.c k_expf.c k_rem_pio2.c k_sin.c k_sinf.c \
k_tan.c k_tanf.c \
polevll.c \
s_asinh.c s_asinhf.c s_atan.c s_atanf.c s_carg.c s_cargf.c s_cargl.c \
s_cbrt.c s_cbrtf.c s_ceil.c s_ceilf.c s_clog.c s_clogf.c \
s_copysign.c s_copysignf.c s_cos.c s_cosf.c \
@ -98,7 +99,7 @@ COMMON_SRCS+= s_copysignl.c s_fabsl.c s_llrintl.c s_lrintl.c s_modfl.c
COMMON_SRCS+= catrigl.c \
e_acoshl.c e_acosl.c e_asinl.c e_atan2l.c e_atanhl.c \
e_coshl.c e_fmodl.c e_hypotl.c \
e_lgammal.c e_lgammal_r.c \
e_lgammal.c e_lgammal_r.c e_powl.c \
e_remainderl.c e_sinhl.c e_sqrtl.c \
invtrig.c k_cosl.c k_sinl.c k_tanl.c \
s_asinhl.c s_atanl.c s_cbrtl.c s_ceill.c \
@ -115,6 +116,7 @@ COMMON_SRCS+= catrig.c catrigf.c \
s_ccosh.c s_ccoshf.c s_cexp.c s_cexpf.c \
s_cimag.c s_cimagf.c s_cimagl.c \
s_conj.c s_conjf.c s_conjl.c \
s_cpow.c s_cpowf.c s_cpowl.c \
s_cproj.c s_cprojf.c s_creal.c s_crealf.c s_creall.c \
s_csinh.c s_csinhf.c s_ctanh.c s_ctanhf.c
@ -134,7 +136,7 @@ INCS+= fenv.h math.h
MAN= acos.3 acosh.3 asin.3 asinh.3 atan.3 atan2.3 atanh.3 \
ceil.3 cacos.3 ccos.3 ccosh.3 cexp.3 \
cimag.3 clog.3 copysign.3 cos.3 cosh.3 csqrt.3 erf.3 \
cimag.3 clog.3 copysign.3 cos.3 cosh.3 cpow.3 csqrt.3 erf.3 \
exp.3 fabs.3 fdim.3 \
feclearexcept.3 feenableexcept.3 fegetenv.3 \
fegetround.3 fenv.3 floor.3 \
@ -172,6 +174,7 @@ MLINKS+=clog.3 clogf.3 clog.3 clogl.3
MLINKS+=copysign.3 copysignf.3 copysign.3 copysignl.3
MLINKS+=cos.3 cosf.3 cos.3 cosl.3
MLINKS+=cosh.3 coshf.3 cosh.3 coshl.3
MLINKS+=cpow.3 cpowf.3 cpow.3 cpowl.3
MLINKS+=csqrt.3 csqrtf.3 csqrt.3 csqrtl.3
MLINKS+=erf.3 erfc.3 erf.3 erff.3 erf.3 erfcf.3 erf.3 erfl.3 erf.3 erfcl.3
MLINKS+=exp.3 expm1.3 exp.3 expm1f.3 exp.3 expm1l.3 exp.3 pow.3 exp.3 powf.3 \

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@ -274,10 +274,10 @@ FBSD_1.3 {
log1pl;
log2l;
logl;
powl;
sinhl;
tanhl;
/* Implemented as weak aliases for imprecise versions */
powl;
tgammal;
};
@ -297,6 +297,9 @@ FBSD_1.5 {
clog;
clogf;
clogl;
cpow;
cpowf;
cpowl;
sincos;
sincosf;
sincosl;

443
lib/msun/ld128/e_powl.c Normal file
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@ -0,0 +1,443 @@
/*-
* ====================================================
* 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.
* ====================================================
*/
/*
* 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(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 113-53 = 60 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. (anything) ** 1 is itself
* 3. (anything) ** 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 NAN
* 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
* 13. -0 ** (-anything except 0, NAN, odd integer) is +INF
* 14. -0 ** (odd integer) = -( +0 ** (odd integer) )
* 15. +INF ** (+anything except 0,NAN) is +INF
* 16. +INF ** (-anything except 0,NAN) is +0
* 17. -INF ** (anything) = -0 ** (-anything)
* 18. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer)
* 19. (-anything except 0 and inf) ** (non-integer) is NAN
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <float.h>
#include <math.h>
#include "math_private.h"
static const long double bp[] = {
1.0L,
1.5L,
};
/* log_2(1.5) */
static const long double dp_h[] = {
0.0,
5.8496250072115607565592654282227158546448E-1L
};
/* Low part of log_2(1.5) */
static const long double dp_l[] = {
0.0,
1.0579781240112554492329533686862998106046E-16L
};
static const long double zero = 0.0L,
one = 1.0L,
two = 2.0L,
two113 = 1.0384593717069655257060992658440192E34L,
huge = 1.0e3000L,
tiny = 1.0e-3000L;
/* 3/2 log x = 3 z + z^3 + z^3 (z^2 R(z^2))
z = (x-1)/(x+1)
1 <= x <= 1.25
Peak relative error 2.3e-37 */
static const long double LN[] =
{
-3.0779177200290054398792536829702930623200E1L,
6.5135778082209159921251824580292116201640E1L,
-4.6312921812152436921591152809994014413540E1L,
1.2510208195629420304615674658258363295208E1L,
-9.9266909031921425609179910128531667336670E-1L
};
static const long double LD[] =
{
-5.129862866715009066465422805058933131960E1L,
1.452015077564081884387441590064272782044E2L,
-1.524043275549860505277434040464085593165E2L,
7.236063513651544224319663428634139768808E1L,
-1.494198912340228235853027849917095580053E1L
/* 1.0E0 */
};
/* exp(x) = 1 + x - x / (1 - 2 / (x - x^2 R(x^2)))
0 <= x <= 0.5
Peak relative error 5.7e-38 */
static const long double PN[] =
{
5.081801691915377692446852383385968225675E8L,
9.360895299872484512023336636427675327355E6L,
4.213701282274196030811629773097579432957E4L,
5.201006511142748908655720086041570288182E1L,
9.088368420359444263703202925095675982530E-3L,
};
static const long double PD[] =
{
3.049081015149226615468111430031590411682E9L,
1.069833887183886839966085436512368982758E8L,
8.259257717868875207333991924545445705394E5L,
1.872583833284143212651746812884298360922E3L,
/* 1.0E0 */
};
static const long double
/* ln 2 */
lg2 = 6.9314718055994530941723212145817656807550E-1L,
lg2_h = 6.9314718055994528622676398299518041312695E-1L,
lg2_l = 2.3190468138462996154948554638754786504121E-17L,
ovt = 8.0085662595372944372e-0017L,
/* 2/(3*log(2)) */
cp = 9.6179669392597560490661645400126142495110E-1L,
cp_h = 9.6179669392597555432899980587535537779331E-1L,
cp_l = 5.0577616648125906047157785230014751039424E-17L;
long double
powl(long double x, long double y)
{
long double z, ax, z_h, z_l, p_h, p_l;
long double yy1, t1, t2, r, s, t, u, v, w;
long double s2, s_h, s_l, t_h, t_l;
int32_t i, j, k, yisint, n;
u_int32_t ix, iy;
int32_t hx, hy;
ieee_quad_shape_type o, p, q;
p.value = x;
hx = p.parts32.mswhi;
ix = hx & 0x7fffffff;
q.value = y;
hy = q.parts32.mswhi;
iy = hy & 0x7fffffff;
/* y==zero: x**0 = 1 */
if ((iy | q.parts32.mswlo | q.parts32.lswhi | q.parts32.lswlo) == 0)
return one;
/* 1.0**y = 1; -1.0**+-Inf = 1 */
if (x == one)
return one;
if (x == -1.0L && iy == 0x7fff0000
&& (q.parts32.mswlo | q.parts32.lswhi | q.parts32.lswlo) == 0)
return one;
/* +-NaN return x+y */
if ((ix > 0x7fff0000)
|| ((ix == 0x7fff0000)
&& ((p.parts32.mswlo | p.parts32.lswhi | p.parts32.lswlo) != 0))
|| (iy > 0x7fff0000)
|| ((iy == 0x7fff0000)
&& ((q.parts32.mswlo | q.parts32.lswhi | q.parts32.lswlo) != 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 >= 0x40700000) /* 2^113 */
yisint = 2; /* even integer y */
else if (iy >= 0x3fff0000) /* 1.0 */
{
if (floorl (y) == y)
{
z = 0.5 * y;
if (floorl (z) == z)
yisint = 2;
else
yisint = 1;
}
}
}
/* special value of y */
if ((q.parts32.mswlo | q.parts32.lswhi | q.parts32.lswlo) == 0)
{
if (iy == 0x7fff0000) /* y is +-inf */
{
if (((ix - 0x3fff0000) | p.parts32.mswlo | p.parts32.lswhi |
p.parts32.lswlo) == 0)
return y - y; /* +-1**inf is NaN */
else if (ix >= 0x3fff0000) /* (|x|>1)**+-inf = inf,0 */
return (hy >= 0) ? y : zero;
else /* (|x|<1)**-,+inf = inf,0 */
return (hy < 0) ? -y : zero;
}
if (iy == 0x3fff0000)
{ /* y is +-1 */
if (hy < 0)
return one / x;
else
return x;
}
if (hy == 0x40000000)
return x * x; /* y is 2 */
if (hy == 0x3ffe0000)
{ /* y is 0.5 */
if (hx >= 0) /* x >= +0 */
return sqrtl (x);
}
}
ax = fabsl (x);
/* special value of x */
if ((p.parts32.mswlo | p.parts32.lswhi | p.parts32.lswlo) == 0)
{
if (ix == 0x7fff0000 || ix == 0 || ix == 0x3fff0000)
{
z = ax; /*x is +-0,+-inf,+-1 */
if (hy < 0)
z = one / z; /* z = (1/|x|) */
if (hx < 0)
{
if (((ix - 0x3fff0000) | 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;
}
}
/* (x<0)**(non-int) is NaN */
if (((((u_int32_t) hx >> 31) - 1) | yisint) == 0)
return (x - x) / (x - x);
/* |y| is huge.
2^-16495 = 1/2 of smallest representable value.
If (1 - 1/131072)^y underflows, y > 1.4986e9 */
if (iy > 0x401d654b)
{
/* if (1 - 2^-113)^y underflows, y > 1.1873e38 */
if (iy > 0x407d654b)
{
if (ix <= 0x3ffeffff)
return (hy < 0) ? huge * huge : tiny * tiny;
if (ix >= 0x3fff0000)
return (hy > 0) ? huge * huge : tiny * tiny;
}
/* over/underflow if x is not close to one */
if (ix < 0x3ffeffff)
return (hy < 0) ? huge * huge : tiny * tiny;
if (ix > 0x3fff0000)
return (hy > 0) ? huge * huge : tiny * tiny;
}
n = 0;
/* take care subnormal number */
if (ix < 0x00010000)
{
ax *= two113;
n -= 113;
o.value = ax;
ix = o.parts32.mswhi;
}
n += ((ix) >> 16) - 0x3fff;
j = ix & 0x0000ffff;
/* determine interval */
ix = j | 0x3fff0000; /* normalize ix */
if (j <= 0x3988)
k = 0; /* |x|<sqrt(3/2) */
else if (j < 0xbb67)
k = 1; /* |x|<sqrt(3) */
else
{
k = 0;
n += 1;
ix -= 0x00010000;
}
o.value = ax;
o.parts32.mswhi = ix;
ax = o.value;
/* compute s = 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 = one / (ax + bp[k]);
s = u * v;
s_h = s;
o.value = s_h;
o.parts32.lswlo = 0;
o.parts32.lswhi &= 0xf8000000;
s_h = o.value;
/* t_h=ax+bp[k] High */
t_h = ax + bp[k];
o.value = t_h;
o.parts32.lswlo = 0;
o.parts32.lswhi &= 0xf8000000;
t_h = o.value;
t_l = ax - (t_h - bp[k]);
s_l = v * ((u - s_h * t_h) - s_h * t_l);
/* compute log(ax) */
s2 = s * s;
u = LN[0] + s2 * (LN[1] + s2 * (LN[2] + s2 * (LN[3] + s2 * LN[4])));
v = LD[0] + s2 * (LD[1] + s2 * (LD[2] + s2 * (LD[3] + s2 * (LD[4] + s2))));
r = s2 * s2 * u / v;
r += s_l * (s_h + s);
s2 = s_h * s_h;
t_h = 3.0 + s2 + r;
o.value = t_h;
o.parts32.lswlo = 0;
o.parts32.lswhi &= 0xf8000000;
t_h = o.value;
t_l = r - ((t_h - 3.0) - s2);
/* u+v = s*(1+...) */
u = s_h * t_h;
v = s_l * t_h + t_l * s;
/* 2/(3log2)*(s+...) */
p_h = u + v;
o.value = p_h;
o.parts32.lswlo = 0;
o.parts32.lswhi &= 0xf8000000;
p_h = o.value;
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) = (s+..)*2/(3*log2) = n + dp_h + z_h + z_l */
t = (long double) n;
t1 = (((z_h + z_l) + dp_h[k]) + t);
o.value = t1;
o.parts32.lswlo = 0;
o.parts32.lswhi &= 0xf8000000;
t1 = o.value;
t2 = z_l - (((t1 - t) - dp_h[k]) - z_h);
/* s (sign of result -ve**odd) = -1 else = 1 */
s = one;
if (((((u_int32_t) hx >> 31) - 1) | (yisint - 1)) == 0)
s = -one; /* (-ve)**(odd int) */
/* split up y into yy1+y2 and compute (yy1+y2)*(t1+t2) */
yy1 = y;
o.value = yy1;
o.parts32.lswlo = 0;
o.parts32.lswhi &= 0xf8000000;
yy1 = o.value;
p_l = (y - yy1) * t1 + y * t2;
p_h = yy1 * t1;
z = p_l + p_h;
o.value = z;
j = o.parts32.mswhi;
if (j >= 0x400d0000) /* z >= 16384 */
{
/* if z > 16384 */
if (((j - 0x400d0000) | o.parts32.mswlo | o.parts32.lswhi |
o.parts32.lswlo) != 0)
return s * huge * huge; /* overflow */
else
{
if (p_l + ovt > z - p_h)
return s * huge * huge; /* overflow */
}
}
else if ((j & 0x7fffffff) >= 0x400d01b9) /* z <= -16495 */
{
/* z < -16495 */
if (((j - 0xc00d01bc) | o.parts32.mswlo | o.parts32.lswhi |
o.parts32.lswlo)
!= 0)
return s * tiny * tiny; /* underflow */
else
{
if (p_l <= z - p_h)
return s * tiny * tiny; /* underflow */
}
}
/* compute 2**(p_h+p_l) */
i = j & 0x7fffffff;
k = (i >> 16) - 0x3fff;
n = 0;
if (i > 0x3ffe0000)
{ /* if |z| > 0.5, set n = [z+0.5] */
n = floorl (z + 0.5L);
t = n;
p_h -= t;
}
t = p_l + p_h;
o.value = t;
o.parts32.lswlo = 0;
o.parts32.lswhi &= 0xf8000000;
t = o.value;
u = t * lg2_h;
v = (p_l - (t - p_h)) * lg2 + t * lg2_l;
z = u + v;
w = v - (z - u);
/* exp(z) */
t = z * z;
u = PN[0] + t * (PN[1] + t * (PN[2] + t * (PN[3] + t * PN[4])));
v = PD[0] + t * (PD[1] + t * (PD[2] + t * (PD[3] + t)));
t1 = z - t * u / v;
r = (z * t1) / (t1 - two) - (w + z * w);
z = one - (r - z);
o.value = z;
j = o.parts32.mswhi;
j += (n << 16);
if ((j >> 16) <= 0)
z = scalbnl (z, n); /* subnormal output */
else
{
o.parts32.mswhi = j;
z = o.value;
}
return s * z;
}

616
lib/msun/ld80/e_powl.c Normal file
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@ -0,0 +1,616 @@
/*-
* 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <float.h>
#include <math.h>
#include "math_private.h"
/* Table size */
#define NXT 32
/* log2(Table size) */
#define LNXT 5
/* 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 long double P[] = {
8.3319510773868690346226E-4L,
4.9000050881978028599627E-1L,
1.7500123722550302671919E0L,
1.4000100839971580279335E0L,
};
static 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 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 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 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 douba(k) A[k]
#define doubb(k) B[k]
#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 volatile long double z;
static long double w, W, Wa, Wb, ya, yb, u;
static const long double huge = 0x1p10000L;
#if 0 /* XXX Prevent gcc from erroneously constant folding this. */
static const long double twom10000 = 0x1p-10000L;
#else
static volatile long double twom10000 = 0x1p-10000L;
#endif
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;
if( y == 0.0L )
return( 1.0L );
if( x == 1.0L )
return( 1.0L );
if( isnan(x) )
return( x );
if( isnan(y) )
return( y );
if( y == 1.0L )
return( x );
if( !isfinite(y) && x == -1.0L )
return( 1.0L );
if( y >= LDBL_MAX )
{
if( x > 1.0L )
return( INFINITY );
if( x > 0.0L && x < 1.0L )
return( 0.0L );
if( x < -1.0L )
return( INFINITY );
if( x > -1.0L && x < 0.0L )
return( 0.0L );
}
if( y <= -LDBL_MAX )
{
if( x > 1.0L )
return( 0.0L );
if( x > 0.0L && x < 1.0L )
return( INFINITY );
if( x < -1.0L )
return( 0.0L );
if( x > -1.0L && x < 0.0L )
return( INFINITY );
}
if( x >= LDBL_MAX )
{
if( y > 0.0L )
return( INFINITY );
return( 0.0L );
}
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(0.5L * ya);
yb = 0.5L * fabsl(w);
if( ya != yb )
yoddint = 1;
}
if( x <= -LDBL_MAX )
{
if( y > 0.0L )
{
if( yoddint )
return( -INFINITY );
return( INFINITY );
}
if( y < 0.0L )
{
if( yoddint )
return( -0.0L );
return( 0.0 );
}
}
nflg = 0; /* flag = 1 if x<0 raised to integer power */
if( x <= 0.0L )
{
if( x == 0.0L )
{
if( y < 0.0 )
{
if( signbit(x) && yoddint )
return( -INFINITY );
return( INFINITY );
}
if( y > 0.0 )
{
if( signbit(x) && yoddint )
return( -0.0L );
return( 0.0 );
}
if( y == 0.0L )
return( 1.0L ); /* 0**0 */
else
return( 0.0L ); /* 0**y */
}
else
{
if( iyflg == 0 )
return (x - x) / (x - x); /* (x<0)**(non-int) is NaN */
nflg = 1;
}
}
/* Integer power of an integer. */
if( iyflg )
{
i = w;
w = floorl(x);
if( (w == x) && (fabsl(y) < 32768.0) )
{
w = powil( x, (int) y );
return( w );
}
}
if( nflg )
x = fabsl(x);
/* separate significand from exponent */
x = frexpl( x, &i );
e = i;
/* find significand in antilog table A[] */
i = 1;
if( x <= douba(17) )
i = 17;
if( x <= douba(i+8) )
i += 8;
if( x <= douba(i+4) )
i += 4;
if( x <= douba(i+2) )
i += 2;
if( x >= douba(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 -= douba(i);
x -= doubb(i/2);
x /= douba(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 - ldexpl( z, -1 ); /* 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 = ldexpl( w, -LNXT ); /* divide by 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 = ldexpl( Ga+Ha, LNXT );
/* 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 > 0.0L )
{
e += 1;
Hb -= (1.0L/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 = douba( e );
z = w * z; /* 2**-e * ( 1 + (2**Hb-1) ) */
z = z + w;
z = ldexpl( z, i ); /* multiply by integer power of 2 */
if( nflg )
{
/* For negative x,
* find out if the integer exponent
* is odd or even.
*/
w = ldexpl( y, -1 );
w = floorl(w);
w = ldexpl( w, 1 );
if( w != y )
z = -z; /* odd exponent */
}
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 = ldexpl( x, LNXT );
t = floorl( t );
t = ldexpl( t, -LNXT );
return(t);
}
/* powil.c
*
* Real raised to integer power, long double precision
*
*
*
* SYNOPSIS:
*
* long double x, y, powil();
* int n;
*
* y = powil( x, n );
*
*
*
* DESCRIPTION:
*
* Returns argument x 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, asign, lx;
if( x == 0.0L )
{
if( nn == 0 )
return( 1.0L );
else if( nn < 0 )
return( LDBL_MAX );
else
return( 0.0L );
}
if( nn == 0 )
return( 1.0L );
if( x < 0.0L )
{
asign = -1;
x = -x;
}
else
asign = 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 - 0.5L + 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+2.0L) )
{
x = 1.0L/x;
sign = -sign;
}
/* First bit of the power */
if( n & 1 )
y = x;
else
{
y = 1.0L;
asign = 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( asign )
y = -y; /* odd power of negative number */
if( sign < 0 )
y = 1.0L/y;
return(y);
}

View File

@ -24,7 +24,7 @@
.\"
.\" $FreeBSD$
.\"
.Dd June 6, 2018
.Dd June 19, 2018
.Dt COMPLEX 3
.Os
.Sh NAME
@ -101,6 +101,7 @@ catan arc tangent
catanh arc hyperbolic tangent
ccos cosine
ccosh hyperbolic cosine
cpow power function
csin sine
csinh hyperbolic sine
ctan tangent
@ -120,7 +121,3 @@ The
.In complex.h
functions described here conform to
.St -isoC-99 .
.Sh BUGS
The power functions
.Fn cpow
are not implemented.

63
lib/msun/man/cpow.3 Normal file
View File

@ -0,0 +1,63 @@
.\" Copyright (c) 2011 Martynas Venckus <martynas@openbsd.org>
.\"
.\" 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.
.\" $FreeBSD$
.\"
.Dd $Mdocdate: June 5 2013 $
.Dt CPOW 3
.Os
.Sh NAME
.Nm cpow ,
.Nm cpowf ,
.Nm cpowl
.Nd complex power functions
.Sh SYNOPSIS
.In complex.h
.Ft double complex
.Fn cpow "double complex x" "double complex z"
.Ft float complex
.Fn cpowf "float complex x" "float complex z"
.Ft long double complex
.Fn cpowl "long double complex x" "long double complex z"
.Sh DESCRIPTION
The
.Fn cpow ,
.Fn cpowf
and
.Fn cpowl
functions compute the complex number
.Fa x
raised to the complex power
.Fa z ,
with a branch cut along the negative real axis for the first argument.
.Sh RETURN VALUES
The
.Fn cpow ,
.Fn cpowf
and
.Fn cpowl
functions return the complex number
.Fa x
raised to the complex power
.Fa z .
.Sh SEE ALSO
.Xr cexp 3 ,
.Xr clog 3
.Sh STANDARDS
The
.Fn cpow ,
.Fn cpowf
and
.Fn cpowl
functions conform to
.St -isoC-99 .

View File

@ -57,6 +57,7 @@ __FBSDID("$FreeBSD$");
* to produce the hexadecimal values shown.
*/
#include <float.h>
#include "math.h"
#include "math_private.h"
@ -307,3 +308,7 @@ __ieee754_pow(double x, double y)
else SET_HIGH_WORD(z,j);
return s*z;
}
#if (LDBL_MANT_DIG == 53)
__weak_reference(pow, powl);
#endif

View File

@ -50,14 +50,6 @@
__weak_reference(imprecise_## x, x);\
WARN_IMPRECISE(x)
long double
imprecise_powl(long double x, long double y)
{
return pow(x, y);
}
DECLARE_WEAK(powl);
#define DECLARE_IMPRECISE(f) \
long double imprecise_ ## f ## l(long double v) { return f(v); }\
DECLARE_WEAK(f ## l)

View File

@ -48,6 +48,47 @@
#define IEEE_WORD_ORDER BYTE_ORDER
#endif
/* A union which permits us to convert between a long double and
four 32 bit ints. */
#if IEEE_WORD_ORDER == BIG_ENDIAN
typedef union
{
long double value;
struct {
u_int32_t mswhi;
u_int32_t mswlo;
u_int32_t lswhi;
u_int32_t lswlo;
} parts32;
struct {
u_int64_t msw;
u_int64_t lsw;
} parts64;
} ieee_quad_shape_type;
#endif
#if IEEE_WORD_ORDER == LITTLE_ENDIAN
typedef union
{
long double value;
struct {
u_int32_t lswlo;
u_int32_t lswhi;
u_int32_t mswlo;
u_int32_t mswhi;
} parts32;
struct {
u_int64_t lsw;
u_int64_t msw;
} parts64;
} ieee_quad_shape_type;
#endif
#if IEEE_WORD_ORDER == BIG_ENDIAN
typedef union
@ -787,4 +828,7 @@ long double __kernel_sinl(long double, long double, int);
long double __kernel_cosl(long double, long double);
long double __kernel_tanl(long double, long double, int);
long double __p1evll(long double, void *, int);
long double __polevll(long double, void *, int);
#endif /* !_MATH_PRIVATE_H_ */

105
lib/msun/src/polevll.c Normal file
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@ -0,0 +1,105 @@
/*-
* 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.
*/
/* polevll.c
* p1evll.c
*
* Evaluate polynomial
*
*
*
* SYNOPSIS:
*
* int N;
* long double x, y, coef[N+1], polevl[];
*
* y = polevll( x, coef, N );
*
*
*
* DESCRIPTION:
*
* Evaluates polynomial of degree N:
*
* 2 N
* y = C + C x + C x +...+ C x
* 0 1 2 N
*
* Coefficients are stored in reverse order:
*
* coef[0] = C , ..., coef[N] = C .
* N 0
*
* The function p1evll() assumes that coef[N] = 1.0 and is
* omitted from the array. Its calling arguments are
* otherwise the same as polevll().
*
*
* SPEED:
*
* In the interest of speed, there are no checks for out
* of bounds arithmetic. This routine is used by most of
* the functions in the library. Depending on available
* equipment features, the user may wish to rewrite the
* program in microcode or assembly language.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <math.h>
#include "math_private.h"
/*
* Polynomial evaluator:
* P[0] x^n + P[1] x^(n-1) + ... + P[n]
*/
long double
__polevll(long double x, void *PP, int n)
{
long double y;
long double *P;
P = (long double *)PP;
y = *P++;
do {
y = y * x + *P++;
} while (--n);
return (y);
}
/*
* Polynomial evaluator:
* x^n + P[0] x^(n-1) + P[1] x^(n-2) + ... + P[n]
*/
long double
__p1evll(long double x, void *PP, int n)
{
long double y;
long double *P;
P = (long double *)PP;
n -= 1;
y = x + *P++;
do {
y = y * x + *P++;
} while (--n);
return (y);
}

74
lib/msun/src/s_cpow.c Normal file
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@ -0,0 +1,74 @@
/*-
* 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.
*/
/* cpow
*
* Complex power function
*
*
*
* SYNOPSIS:
*
* double complex cpow();
* double complex a, z, w;
*
* w = cpow (a, z);
*
*
*
* DESCRIPTION:
*
* Raises complex A to the complex Zth power.
* Definition is per AMS55 # 4.2.8,
* analytically equivalent to cpow(a,z) = cexp(z clog(a)).
*
* ACCURACY:
*
* Relative error:
* arithmetic domain # trials peak rms
* IEEE -10,+10 30000 9.4e-15 1.5e-15
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <complex.h>
#include <float.h>
#include <math.h>
double complex
cpow(double complex a, double complex z)
{
double complex w;
double x, y, r, theta, absa, arga;
x = creal (z);
y = cimag (z);
absa = cabs (a);
if (absa == 0.0) {
return (0.0 + 0.0 * I);
}
arga = carg (a);
r = pow (absa, x);
theta = x * arga;
if (y != 0.0) {
r = r * exp (-y * arga);
theta = theta + y * log (absa);
}
w = r * cos (theta) + (r * sin (theta)) * I;
return (w);
}

73
lib/msun/src/s_cpowf.c Normal file
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@ -0,0 +1,73 @@
/*-
* 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.
*/
/* cpowf
*
* Complex power function
*
*
*
* SYNOPSIS:
*
* float complex cpowf();
* float complex a, z, w;
*
* w = cpowf (a, z);
*
*
*
* DESCRIPTION:
*
* Raises complex A to the complex Zth power.
* Definition is per AMS55 # 4.2.8,
* analytically equivalent to cpow(a,z) = cexp(z clog(a)).
*
* ACCURACY:
*
* Relative error:
* arithmetic domain # trials peak rms
* IEEE -10,+10 30000 9.4e-15 1.5e-15
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <complex.h>
#include <math.h>
float complex
cpowf(float complex a, float complex z)
{
float complex w;
float x, y, r, theta, absa, arga;
x = crealf(z);
y = cimagf(z);
absa = cabsf (a);
if (absa == 0.0f) {
return (0.0f + 0.0f * I);
}
arga = cargf (a);
r = powf (absa, x);
theta = x * arga;
if (y != 0.0f) {
r = r * expf (-y * arga);
theta = theta + y * logf (absa);
}
w = r * cosf (theta) + (r * sinf (theta)) * I;
return (w);
}

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@ -0,0 +1,73 @@
/*-
* 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.
*/
/* cpowl
*
* Complex power function
*
*
*
* SYNOPSIS:
*
* long double complex cpowl();
* long double complex a, z, w;
*
* w = cpowl (a, z);
*
*
*
* DESCRIPTION:
*
* Raises complex A to the complex Zth power.
* Definition is per AMS55 # 4.2.8,
* analytically equivalent to cpow(a,z) = cexp(z clog(a)).
*
* ACCURACY:
*
* Relative error:
* arithmetic domain # trials peak rms
* IEEE -10,+10 30000 9.4e-15 1.5e-15
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <complex.h>
#include <math.h>
long double complex
cpowl(long double complex a, long double complex z)
{
long double complex w;
long double x, y, r, theta, absa, arga;
x = creall(z);
y = cimagl(z);
absa = cabsl(a);
if (absa == 0.0L) {
return (0.0L + 0.0L * I);
}
arga = cargl(a);
r = powl(absa, x);
theta = x * arga;
if (y != 0.0L) {
r = r * expl(-y * arga);
theta = theta + y * logl(absa);
}
w = r * cosl(theta) + (r * sinl(theta)) * I;
return (w);
}