diff options
Diffstat (limited to 'sysdeps/libm-ieee754/s_lroundl.c')
| -rw-r--r-- | sysdeps/libm-ieee754/s_lroundl.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_lroundl.c b/sysdeps/libm-ieee754/s_lroundl.c new file mode 100644 index 0000000000..d8b7db4b5c --- /dev/null +++ b/sysdeps/libm-ieee754/s_lroundl.c @@ -0,0 +1,78 @@ +/* Round long double value to long int. + Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. 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" + + +long int +__lroundl (long double x) +{ + int32_t j0; + u_int32_t se, i1, i0; + long int result; + int sign; + + GET_LDOUBLE_WORDS (se, i0, i1, x); + j0 = (se & 0x7fff) - 0x3fff; + sign = (se & 0x8000) != 0 ? -1 : 1; + + if (j0 < 31) + { + if (j0 < 0) + return j0 < -1 ? 0 : sign; + else + { + u_int32_t j = i0 + (0x40000000 >> j0); + if (j < i0) + { + j >>= 1; + j |= 0x80000000; + ++j0; + } + + result = j >> (31 - j0); + } + } + else if (j0 < (int32_t) (8 * sizeof (long int))) + { + if (j0 >= 63) + result = ((long int) i0 << (j0 - 31)) | (i1 << (j0 - 63)); + else + { + u_int32_t j = i1 + (0x80000000 >> (j0 - 31)); + if (j < i1) + ++i0; + + result = ((long int) i0 << (j0 - 31)) | (j >> (63 - j0)); + } + } + else + { + /* The number is too large. It is left implementation defined + what happens. */ + return (long int) x; + } + + return sign * result; +} + +weak_alias (__lroundl, lroundl) |