glibc/sysdeps/ieee754/ldbl-128/k_cosl.c
Paul Eggert 5a82c74822 Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:

sed -ri '
  s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
  s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
  $(find $(git ls-files) -prune -type f \
      ! -name '*.po' \
      ! -name 'ChangeLog*' \
      ! -path COPYING ! -path COPYING.LIB \
      ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
      ! -path manual/texinfo.tex ! -path scripts/config.guess \
      ! -path scripts/config.sub ! -path scripts/install-sh \
      ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
      ! -path INSTALL ! -path  locale/programs/charmap-kw.h \
      ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
      ! '(' -name configure \
            -execdir test -f configure.ac -o -f configure.in ';' ')' \
      ! '(' -name preconfigure \
            -execdir test -f preconfigure.ac ';' ')' \
      -print)

and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:

  chmod a+x sysdeps/unix/sysv/linux/riscv/configure
  # Omit irrelevant whitespace and comment-only changes,
  # perhaps from a slightly-different Autoconf version.
  git checkout -f \
    sysdeps/csky/configure \
    sysdeps/hppa/configure \
    sysdeps/riscv/configure \
    sysdeps/unix/sysv/linux/csky/configure
  # Omit changes that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
  git checkout -f \
    sysdeps/powerpc/powerpc64/ppc-mcount.S \
    sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
  # Omit change that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
  git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 02:43:31 -07:00

132 lines
5.1 KiB
C

/* Quad-precision floating point cosine on <-pi/4,pi/4>.
Copyright (C) 1999-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jj@ultra.linux.cz>
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
<https://www.gnu.org/licenses/>. */
#include <math.h>
#include <math_private.h>
static const _Float128 c[] = {
#define ONE c[0]
L(1.00000000000000000000000000000000000E+00), /* 3fff0000000000000000000000000000 */
/* cos x ~ ONE + x^2 ( SCOS1 + SCOS2 * x^2 + ... + SCOS4 * x^6 + SCOS5 * x^8 )
x in <0,1/256> */
#define SCOS1 c[1]
#define SCOS2 c[2]
#define SCOS3 c[3]
#define SCOS4 c[4]
#define SCOS5 c[5]
L(-5.00000000000000000000000000000000000E-01), /* bffe0000000000000000000000000000 */
L(4.16666666666666666666666666556146073E-02), /* 3ffa5555555555555555555555395023 */
L(-1.38888888888888888888309442601939728E-03), /* bff56c16c16c16c16c16a566e42c0375 */
L(2.48015873015862382987049502531095061E-05), /* 3fefa01a01a019ee02dcf7da2d6d5444 */
L(-2.75573112601362126593516899592158083E-07), /* bfe927e4f5dce637cb0b54908754bde0 */
/* cos x ~ ONE + x^2 ( COS1 + COS2 * x^2 + ... + COS7 * x^12 + COS8 * x^14 )
x in <0,0.1484375> */
#define COS1 c[6]
#define COS2 c[7]
#define COS3 c[8]
#define COS4 c[9]
#define COS5 c[10]
#define COS6 c[11]
#define COS7 c[12]
#define COS8 c[13]
L(-4.99999999999999999999999999999999759E-01), /* bffdfffffffffffffffffffffffffffb */
L(4.16666666666666666666666666651287795E-02), /* 3ffa5555555555555555555555516f30 */
L(-1.38888888888888888888888742314300284E-03), /* bff56c16c16c16c16c16c16a463dfd0d */
L(2.48015873015873015867694002851118210E-05), /* 3fefa01a01a01a01a0195cebe6f3d3a5 */
L(-2.75573192239858811636614709689300351E-07), /* bfe927e4fb7789f5aa8142a22044b51f */
L(2.08767569877762248667431926878073669E-09), /* 3fe21eed8eff881d1e9262d7adff4373 */
L(-1.14707451049343817400420280514614892E-11), /* bfda9397496922a9601ed3d4ca48944b */
L(4.77810092804389587579843296923533297E-14), /* 3fd2ae5f8197cbcdcaf7c3fb4523414c */
/* sin x ~ ONE * x + x^3 ( SSIN1 + SSIN2 * x^2 + ... + SSIN4 * x^6 + SSIN5 * x^8 )
x in <0,1/256> */
#define SSIN1 c[14]
#define SSIN2 c[15]
#define SSIN3 c[16]
#define SSIN4 c[17]
#define SSIN5 c[18]
L(-1.66666666666666666666666666666666659E-01), /* bffc5555555555555555555555555555 */
L(8.33333333333333333333333333146298442E-03), /* 3ff81111111111111111111110fe195d */
L(-1.98412698412698412697726277416810661E-04), /* bff2a01a01a01a01a019e7121e080d88 */
L(2.75573192239848624174178393552189149E-06), /* 3fec71de3a556c640c6aaa51aa02ab41 */
L(-2.50521016467996193495359189395805639E-08), /* bfe5ae644ee90c47dc71839de75b2787 */
};
#define SINCOSL_COS_HI 0
#define SINCOSL_COS_LO 1
#define SINCOSL_SIN_HI 2
#define SINCOSL_SIN_LO 3
extern const _Float128 __sincosl_table[];
_Float128
__kernel_cosl(_Float128 x, _Float128 y)
{
_Float128 h, l, z, sin_l, cos_l_m1;
int64_t ix;
uint32_t tix, hix, index;
GET_LDOUBLE_MSW64 (ix, x);
tix = ((uint64_t)ix) >> 32;
tix &= ~0x80000000; /* tix = |x|'s high 32 bits */
if (tix < 0x3ffc3000) /* |x| < 0.1484375 */
{
/* Argument is small enough to approximate it by a Chebyshev
polynomial of degree 16. */
if (tix < 0x3fc60000) /* |x| < 2^-57 */
if (!((int)x)) return ONE; /* generate inexact */
z = x * x;
return ONE + (z*(COS1+z*(COS2+z*(COS3+z*(COS4+
z*(COS5+z*(COS6+z*(COS7+z*COS8))))))));
}
else
{
/* So that we don't have to use too large polynomial, we find
l and h such that x = l + h, where fabsl(l) <= 1.0/256 with 83
possible values for h. We look up cosl(h) and sinl(h) in
pre-computed tables, compute cosl(l) and sinl(l) using a
Chebyshev polynomial of degree 10(11) and compute
cosl(h+l) = cosl(h)cosl(l) - sinl(h)sinl(l). */
index = 0x3ffe - (tix >> 16);
hix = (tix + (0x200 << index)) & (0xfffffc00 << index);
if (signbit (x))
{
x = -x;
y = -y;
}
switch (index)
{
case 0: index = ((45 << 10) + hix - 0x3ffe0000) >> 8; break;
case 1: index = ((13 << 11) + hix - 0x3ffd0000) >> 9; break;
default:
case 2: index = (hix - 0x3ffc3000) >> 10; break;
}
SET_LDOUBLE_WORDS64(h, ((uint64_t)hix) << 32, 0);
l = y - (h - x);
z = l * l;
sin_l = l*(ONE+z*(SSIN1+z*(SSIN2+z*(SSIN3+z*(SSIN4+z*SSIN5)))));
cos_l_m1 = z*(SCOS1+z*(SCOS2+z*(SCOS3+z*(SCOS4+z*SCOS5))));
return __sincosl_table [index + SINCOSL_COS_HI]
+ (__sincosl_table [index + SINCOSL_COS_LO]
- (__sincosl_table [index + SINCOSL_SIN_HI] * sin_l
- __sincosl_table [index + SINCOSL_COS_HI] * cos_l_m1));
}
}