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authorRoland McGrath <roland@gnu.org>2006-01-28 00:15:15 +0000
committerRoland McGrath <roland@gnu.org>2006-01-28 00:15:15 +0000
commitf964490f3c4f094fd684960c2e98885b23e31376 (patch)
treee10f697bd55240b9be7a9c1a5109ee07893d3136 /sysdeps/ieee754/ldbl-128ibm/e_log2l.c
parentd421a7801d1bdfd8175e53a79068833ae4de56b1 (diff)
2006-01-27 Dwayne Grant McConnell <decimal@us.ibm.com>cvs/fedora-glibc-20060130T0922
Jakub Jelinek <jakub@redhat.com> Roland McGrath <roland@redhat.com> Steven Munroe <sjmunroe@us.ibm.com> Alan Modra <amodra@bigpond.net.au> * sysdeps/powerpc/powerpc64/fpu/s_truncf.S: Comment fix. * sysdeps/powerpc/powerpc32/fpu/s_truncf.S: Likewise. * sysdeps/powerpc/powerpc64/fpu/s_llroundf.S: Likewise. * sysdeps/powerpc/fpu/libm-test-ulps: Update. * math/libm-test.inc (check_float_internal): Allow ulp <= 0.5. (erfc_test): Don't run erfcl (27.0L) test if erfcl (27.0L) is denormal. [TEST_LDOUBLE] (ceil_test, floor_test, llrint_test, llround_test, rint_test, round_test, trunc_test): Add new tests. * sysdeps/powerpc/powerpc32/fpu/s_copysignl.S: New file. * sysdeps/powerpc/powerpc32/fpu/s_fabs.S: New file. * sysdeps/powerpc/powerpc32/fpu/s_fabsl.S: New file. * sysdeps/powerpc/powerpc32/fpu/s_fdim.c: New file. * sysdeps/powerpc/powerpc32/fpu/s_fmax.S: New file. * sysdeps/powerpc/powerpc32/fpu/s_fmin.S: New file. * sysdeps/powerpc/powerpc32/fpu/s_isnan.c: New file. * sysdeps/powerpc/powerpc64/fpu/s_ceill.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_copysignl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_fabs.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_fabsl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_fdim.c: New file. * sysdeps/powerpc/powerpc64/fpu/s_floorl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_fmax.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_fmin.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_isnan.c: New file. * sysdeps/powerpc/powerpc64/fpu/s_llrintl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_llroundl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_lrintl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_lroundl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_nearbyintl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_rintl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_roundl.S: New file. * sysdeps/powerpc/powerpc64/fpu/s_truncl.S: New file. * sysdeps/unix/sysv/linux/powerpc/Implies: New file. * sysdeps/unix/sysv/linux/powerpc/powerpc64/fpu/Implies: New file. * sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/Implies: New file. * sysdeps/unix/sysv/linux/powerpc/configure.in: New file. * sysdeps/unix/sysv/linux/powerpc/configure: New file. * sysdeps/unix/sysv/linux/powerpc/bits/wordsize.h (__LONG_DOUBLE_MATH_OPTIONAL): Define. (__NO_LONG_DOUBLE_MATH): Define. * sysdeps/unix/sysv/linux/powerpc/nldbl-abi.h: New file. * sysdeps/powerpc/fpu/s_isnan.c: Include math_ldbl_opt.h. * sysdeps/powerpc/powerpc64/fpu/s_ceil.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (ceill): Add compatibility symbols. * sysdeps/powerpc/powerpc64/fpu/s_copysign.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (copysignl): Add compatibility symbols. * sysdeps/powerpc/powerpc64/fpu/s_floor.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (floorl): Add compatibility symbols. * sysdeps/powerpc/powerpc64/fpu/s_llrint.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (llrintl, lrintl): Add compatibility symbols. * sysdeps/powerpc/powerpc64/fpu/s_llround.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (llroundl, lroundl): Add compatibility symbols. * sysdeps/powerpc/powerpc64/fpu/s_rint.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (rintl): Add compatibility symbols. * sysdeps/powerpc/powerpc64/fpu/s_round.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (roundl): Add compatibility symbols. * sysdeps/powerpc/powerpc64/fpu/s_trunc.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (truncl): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_ceil.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (ceill): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_copysign.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (copysignl): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_floor.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (floorl): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_lrint.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (lrintl): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_llrint.c: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (llrintl): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_lround.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (lroundl): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_rint.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (rintl): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_round.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (roundl): Add compatibility symbols. * sysdeps/powerpc/powerpc32/fpu/s_trunc.S: Include math_ldbl_opt.h. [LONG_DOUBLE_COMPAT] (truncl): Add compatibility symbols. * misc/qefgcvt_r.c [LDBL_MIN_10_EXP == -291] (FLOAT_MIN_10_NORM): New. * sysdeps/powerpc/fpu/bits/mathdef.h (__NO_LONG_DOUBLE_MATH): Remove. * sysdeps/powerpc/Implies: Add ieee754/ldbl-128ibm. * sysdeps/powerpc/powerpc32/Implies: Remove powerpc/soft-fp. * sysdeps/ieee754/ldbl-128ibm/Makefile: New file. * sysdeps/ieee754/ldbl-128ibm/e_acoshl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_acosl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_asinl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_atan2l.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_atanhl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_coshl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_expl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_fmodl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_hypotl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_j0l.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_j1l.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_jnl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_lgammal_r.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_log10l.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_log2l.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_logl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_powl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_rem_pio2l.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_remainderl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_sinhl.c: New file. * sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c: New file. * sysdeps/ieee754/ldbl-128ibm/ieee754.h: New file. * sysdeps/ieee754/ldbl-128ibm/k_cosl.c: New file. * sysdeps/ieee754/ldbl-128ibm/k_sincosl.c: New file. * sysdeps/ieee754/ldbl-128ibm/k_sinl.c: New file. * sysdeps/ieee754/ldbl-128ibm/k_tanl.c: New file. * sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c: New file. * sysdeps/ieee754/ldbl-128ibm/math_ldbl.h: New file. * sysdeps/ieee754/ldbl-128ibm/mpn2ldbl.c: New file. * sysdeps/ieee754/ldbl-128ibm/printf_fphex.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_asinhl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_atanl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_cbrtl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_cosl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_erfl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_expm1l.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_fabsl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_finitel.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_fpclassifyl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_frexpl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_ilogbl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_isinfl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_isnanl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_log1pl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_logbl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_modfl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_remquol.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_rintl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_scalblnl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_scalbnl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_signbitl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_sincosl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_sinl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_tanhl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_tanl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_truncl.c: New file. * sysdeps/ieee754/ldbl-128ibm/strtold_l.c: New file. * sysdeps/ieee754/ldbl-128ibm/t_sincosl.c: New file. * sysdeps/ieee754/ldbl-128ibm/w_expl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_copysignl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_floorl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_llrintl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_llroundl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_roundl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_ceill.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_lrintl.c: New file. * sysdeps/ieee754/ldbl-128ibm/s_lroundl.c: New file. * sysdeps/ieee754/ldbl-128/e_powl.c: Fix old comment.
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/e_log2l.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/e_log2l.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_log2l.c b/sysdeps/ieee754/ldbl-128ibm/e_log2l.c
new file mode 100644
index 0000000000..fe8a8e1d6c
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/e_log2l.c
@@ -0,0 +1,250 @@
+/* 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);
+}