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-rw-r--r--sysdeps/ieee754/ldbl-128ibm/e_log2l.c250
1 files changed, 0 insertions, 250 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_log2l.c b/sysdeps/ieee754/ldbl-128ibm/e_log2l.c
deleted file mode 100644
index fe8a8e1d6c..0000000000
--- a/sysdeps/ieee754/ldbl-128ibm/e_log2l.c
+++ /dev/null
@@ -1,250 +0,0 @@
-/*                                                      log2l.c
- *      Base 2 logarithm, 128-bit long double precision
- *
- *
- *
- * SYNOPSIS:
- *
- * long double x, y, log2l();
- *
- * y = log2l( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns the base 2 logarithm of x.
- *
- * The argument is separated into its exponent and fractional
- * parts.  If the exponent is between -1 and +1, the (natural)
- * logarithm of the fraction is approximated by
- *
- *     log(1+x) = x - 0.5 x^2 + x^3 P(x)/Q(x).
- *
- * Otherwise, setting  z = 2(x-1)/x+1),
- *
- *     log(x) = z + z^3 P(z)/Q(z).
- *
- *
- *
- * ACCURACY:
- *
- *                      Relative error:
- * arithmetic   domain     # trials      peak         rms
- *    IEEE      0.5, 2.0     100,000    2.6e-34     4.9e-35
- *    IEEE     exp(+-10000)  100,000    9.6e-35     4.0e-35
- *
- * In the tests over the interval exp(+-10000), the logarithms
- * of the random arguments were uniformly distributed over
- * [-10000, +10000].
- *
- */
-
-/*
-   Cephes Math Library Release 2.2:  January, 1991
-   Copyright 1984, 1991 by Stephen L. Moshier
-   Adapted for glibc November, 2001
-
-    This 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.
-
-    This 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 this library; if not, write to the Free Software
-    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
- */
-
-#include "math.h"
-#include "math_private.h"
-
-/* Coefficients for ln(1+x) = x - x**2/2 + x**3 P(x)/Q(x)
- * 1/sqrt(2) <= x < sqrt(2)
- * Theoretical peak relative error = 5.3e-37,
- * relative peak error spread = 2.3e-14
- */
-static const long double P[13] =
-{
-  1.313572404063446165910279910527789794488E4L,
-  7.771154681358524243729929227226708890930E4L,
-  2.014652742082537582487669938141683759923E5L,
-  3.007007295140399532324943111654767187848E5L,
-  2.854829159639697837788887080758954924001E5L,
-  1.797628303815655343403735250238293741397E5L,
-  7.594356839258970405033155585486712125861E4L,
-  2.128857716871515081352991964243375186031E4L,
-  3.824952356185897735160588078446136783779E3L,
-  4.114517881637811823002128927449878962058E2L,
-  2.321125933898420063925789532045674660756E1L,
-  4.998469661968096229986658302195402690910E-1L,
-  1.538612243596254322971797716843006400388E-6L
-};
-static const long double Q[12] =
-{
-  3.940717212190338497730839731583397586124E4L,
-  2.626900195321832660448791748036714883242E5L,
-  7.777690340007566932935753241556479363645E5L,
-  1.347518538384329112529391120390701166528E6L,
-  1.514882452993549494932585972882995548426E6L,
-  1.158019977462989115839826904108208787040E6L,
-  6.132189329546557743179177159925690841200E5L,
-  2.248234257620569139969141618556349415120E5L,
-  5.605842085972455027590989944010492125825E4L,
-  9.147150349299596453976674231612674085381E3L,
-  9.104928120962988414618126155557301584078E2L,
-  4.839208193348159620282142911143429644326E1L
-/* 1.000000000000000000000000000000000000000E0L, */
-};
-
-/* Coefficients for log(x) = z + z^3 P(z^2)/Q(z^2),
- * where z = 2(x-1)/(x+1)
- * 1/sqrt(2) <= x < sqrt(2)
- * Theoretical peak relative error = 1.1e-35,
- * relative peak error spread 1.1e-9
- */
-static const long double R[6] =
-{
-  1.418134209872192732479751274970992665513E5L,
- -8.977257995689735303686582344659576526998E4L,
-  2.048819892795278657810231591630928516206E4L,
- -2.024301798136027039250415126250455056397E3L,
-  8.057002716646055371965756206836056074715E1L,
- -8.828896441624934385266096344596648080902E-1L
-};
-static const long double S[6] =
-{
-  1.701761051846631278975701529965589676574E6L,
- -1.332535117259762928288745111081235577029E6L,
-  4.001557694070773974936904547424676279307E5L,
- -5.748542087379434595104154610899551484314E4L,
-  3.998526750980007367835804959888064681098E3L,
- -1.186359407982897997337150403816839480438E2L
-/* 1.000000000000000000000000000000000000000E0L, */
-};
-
-static const long double
-/* log2(e) - 1 */
-LOG2EA = 4.4269504088896340735992468100189213742664595E-1L,
-/* sqrt(2)/2 */
-SQRTH = 7.071067811865475244008443621048490392848359E-1L;
-
-
-/* Evaluate P[n] x^n  +  P[n-1] x^(n-1)  +  ...  +  P[0] */
-
-static long double
-neval (long double x, const long double *p, int n)
-{
-  long double y;
-
-  p += n;
-  y = *p--;
-  do
-    {
-      y = y * x + *p--;
-    }
-  while (--n > 0);
-  return y;
-}
-
-
-/* Evaluate x^n+1  +  P[n] x^(n)  +  P[n-1] x^(n-1)  +  ...  +  P[0] */
-
-static long double
-deval (long double x, const long double *p, int n)
-{
-  long double y;
-
-  p += n;
-  y = x + *p--;
-  do
-    {
-      y = y * x + *p--;
-    }
-  while (--n > 0);
-  return y;
-}
-
-
-
-long double
-__ieee754_log2l (x)
-     long double x;
-{
-  long double z;
-  long double y;
-  int e;
-  int64_t hx, lx;
-
-/* Test for domain */
-  GET_LDOUBLE_WORDS64 (hx, lx, x);
-  if (((hx & 0x7fffffffffffffffLL) | (lx & 0x7fffffffffffffffLL)) == 0)
-    return (-1.0L / (x - x));
-  if (hx < 0)
-    return (x - x) / (x - x);
-  if (hx >= 0x7ff0000000000000LL)
-    return (x + x);
-
-/* separate mantissa from exponent */
-
-/* Note, frexp is used so that denormal numbers
- * will be handled properly.
- */
-  x = __frexpl (x, &e);
-
-
-/* logarithm using log(x) = z + z**3 P(z)/Q(z),
- * where z = 2(x-1)/x+1)
- */
-  if ((e > 2) || (e < -2))
-    {
-      if (x < SQRTH)
-	{			/* 2( 2x-1 )/( 2x+1 ) */
-	  e -= 1;
-	  z = x - 0.5L;
-	  y = 0.5L * z + 0.5L;
-	}
-      else
-	{			/*  2 (x-1)/(x+1)   */
-	  z = x - 0.5L;
-	  z -= 0.5L;
-	  y = 0.5L * x + 0.5L;
-	}
-      x = z / y;
-      z = x * x;
-      y = x * (z * neval (z, R, 5) / deval (z, S, 5));
-      goto done;
-    }
-
-
-/* logarithm using log(1+x) = x - .5x**2 + x**3 P(x)/Q(x) */
-
-  if (x < SQRTH)
-    {
-      e -= 1;
-      x = 2.0 * x - 1.0L;	/*  2x - 1  */
-    }
-  else
-    {
-      x = x - 1.0L;
-    }
-  z = x * x;
-  y = x * (z * neval (x, P, 12) / deval (x, Q, 11));
-  y = y - 0.5 * z;
-
-done:
-
-/* Multiply log of fraction by log2(e)
- * and base 2 exponent by 1
- */
-  z = y * LOG2EA;
-  z += x * LOG2EA;
-  z += y;
-  z += x;
-  z += e;
-  return (z);
-}