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diff --git a/sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c b/sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c
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-/* Implementation of gamma function according to ISO C.
- Copyright (C) 1997-2017 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
- Jakub Jelinek <jj@ultra.linux.cz, 1999.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#include <math.h>
-#include <math_private.h>
-#include <float.h>
-
-/* Coefficients B_2k / 2k(2k-1) of x^-(2k-1) inside exp in Stirling's
- approximation to gamma function. */
-
-static const long double gamma_coeff[] =
- {
- 0x1.555555555555555555555555558p-4L,
- -0xb.60b60b60b60b60b60b60b60b6p-12L,
- 0x3.4034034034034034034034034p-12L,
- -0x2.7027027027027027027027027p-12L,
- 0x3.72a3c5631fe46ae1d4e700dca9p-12L,
- -0x7.daac36664f1f207daac36664f2p-12L,
- 0x1.a41a41a41a41a41a41a41a41a4p-8L,
- -0x7.90a1b2c3d4e5f708192a3b4c5ep-8L,
- 0x2.dfd2c703c0cfff430edfd2c704p-4L,
- -0x1.6476701181f39edbdb9ce625988p+0L,
- 0xd.672219167002d3a7a9c886459cp+0L,
- -0x9.cd9292e6660d55b3f712eb9e08p+4L,
- 0x8.911a740da740da740da740da74p+8L,
- };
-
-#define NCOEFF (sizeof (gamma_coeff) / sizeof (gamma_coeff[0]))
-
-/* Return gamma (X), for positive X less than 191, in the form R *
- 2^(*EXP2_ADJ), where R is the return value and *EXP2_ADJ is set to
- avoid overflow or underflow in intermediate calculations. */
-
-static long double
-gammal_positive (long double x, int *exp2_adj)
-{
- int local_signgam;
- if (x < 0.5L)
- {
- *exp2_adj = 0;
- return __ieee754_expl (__ieee754_lgammal_r (x + 1, &local_signgam)) / x;
- }
- else if (x <= 1.5L)
- {
- *exp2_adj = 0;
- return __ieee754_expl (__ieee754_lgammal_r (x, &local_signgam));
- }
- else if (x < 11.5L)
- {
- /* Adjust into the range for using exp (lgamma). */
- *exp2_adj = 0;
- long double n = __ceill (x - 1.5L);
- long double x_adj = x - n;
- long double eps;
- long double prod = __gamma_productl (x_adj, 0, n, &eps);
- return (__ieee754_expl (__ieee754_lgammal_r (x_adj, &local_signgam))
- * prod * (1.0L + eps));
- }
- else
- {
- long double eps = 0;
- long double x_eps = 0;
- long double x_adj = x;
- long double prod = 1;
- if (x < 23.0L)
- {
- /* Adjust into the range for applying Stirling's
- approximation. */
- long double n = __ceill (23.0L - x);
- x_adj = x + n;
- x_eps = (x - (x_adj - n));
- prod = __gamma_productl (x_adj - n, x_eps, n, &eps);
- }
- /* The result is now gamma (X_ADJ + X_EPS) / (PROD * (1 + EPS)).
- Compute gamma (X_ADJ + X_EPS) using Stirling's approximation,
- starting by computing pow (X_ADJ, X_ADJ) with a power of 2
- factored out. */
- long double exp_adj = -eps;
- long double x_adj_int = __roundl (x_adj);
- long double x_adj_frac = x_adj - x_adj_int;
- int x_adj_log2;
- long double x_adj_mant = __frexpl (x_adj, &x_adj_log2);
- if (x_adj_mant < M_SQRT1_2l)
- {
- x_adj_log2--;
- x_adj_mant *= 2.0L;
- }
- *exp2_adj = x_adj_log2 * (int) x_adj_int;
- long double ret = (__ieee754_powl (x_adj_mant, x_adj)
- * __ieee754_exp2l (x_adj_log2 * x_adj_frac)
- * __ieee754_expl (-x_adj)
- * __ieee754_sqrtl (2 * M_PIl / x_adj)
- / prod);
- exp_adj += x_eps * __ieee754_logl (x_adj);
- long double bsum = gamma_coeff[NCOEFF - 1];
- long double x_adj2 = x_adj * x_adj;
- for (size_t i = 1; i <= NCOEFF - 1; i++)
- bsum = bsum / x_adj2 + gamma_coeff[NCOEFF - 1 - i];
- exp_adj += bsum / x_adj;
- return ret + ret * __expm1l (exp_adj);
- }
-}
-
-long double
-__ieee754_gammal_r (long double x, int *signgamp)
-{
- int64_t hx;
- double xhi;
- long double ret;
-
- xhi = ldbl_high (x);
- EXTRACT_WORDS64 (hx, xhi);
-
- if ((hx & 0x7fffffffffffffffLL) == 0)
- {
- /* Return value for x == 0 is Inf with divide by zero exception. */
- *signgamp = 0;
- return 1.0 / x;
- }
- if (hx < 0 && (u_int64_t) hx < 0xfff0000000000000ULL && __rintl (x) == x)
- {
- /* Return value for integer x < 0 is NaN with invalid exception. */
- *signgamp = 0;
- return (x - x) / (x - x);
- }
- if (hx == 0xfff0000000000000ULL)
- {
- /* x == -Inf. According to ISO this is NaN. */
- *signgamp = 0;
- return x - x;
- }
- if ((hx & 0x7ff0000000000000ULL) == 0x7ff0000000000000ULL)
- {
- /* Positive infinity (return positive infinity) or NaN (return
- NaN). */
- *signgamp = 0;
- return x + x;
- }
-
- if (x >= 172.0L)
- {
- /* Overflow. */
- *signgamp = 0;
- return LDBL_MAX * LDBL_MAX;
- }
- else
- {
- SET_RESTORE_ROUNDL (FE_TONEAREST);
- if (x > 0.0L)
- {
- *signgamp = 0;
- int exp2_adj;
- ret = gammal_positive (x, &exp2_adj);
- ret = __scalbnl (ret, exp2_adj);
- }
- else if (x >= -0x1p-110L)
- {
- *signgamp = 0;
- ret = 1.0L / x;
- }
- else
- {
- long double tx = __truncl (x);
- *signgamp = (tx == 2.0L * __truncl (tx / 2.0L)) ? -1 : 1;
- if (x <= -191.0L)
- /* Underflow. */
- ret = LDBL_MIN * LDBL_MIN;
- else
- {
- long double frac = tx - x;
- if (frac > 0.5L)
- frac = 1.0L - frac;
- long double sinpix = (frac <= 0.25L
- ? __sinl (M_PIl * frac)
- : __cosl (M_PIl * (0.5L - frac)));
- int exp2_adj;
- ret = M_PIl / (-x * sinpix
- * gammal_positive (-x, &exp2_adj));
- ret = __scalbnl (ret, -exp2_adj);
- math_check_force_underflow_nonneg (ret);
- }
- }
- }
- if (isinf (ret) && x != 0)
- {
- if (*signgamp < 0)
- return -(-__copysignl (LDBL_MAX, ret) * LDBL_MAX);
- else
- return __copysignl (LDBL_MAX, ret) * LDBL_MAX;
- }
- else if (ret == 0)
- {
- if (*signgamp < 0)
- return -(-__copysignl (LDBL_MIN, ret) * LDBL_MIN);
- else
- return __copysignl (LDBL_MIN, ret) * LDBL_MIN;
- }
- else
- return ret;
-}
-strong_alias (__ieee754_gammal_r, __gammal_r_finite)
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