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Diffstat (limited to 'libquadmath/math/llroundq.c')
| -rw-r--r-- | libquadmath/math/llroundq.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/libquadmath/math/llroundq.c b/libquadmath/math/llroundq.c new file mode 100644 index 000000000..c108e7ad1 --- /dev/null +++ b/libquadmath/math/llroundq.c @@ -0,0 +1,73 @@ +/* Round long double value to long long int. + Copyright (C) 1997, 1999, 2004 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include "quadmath-imp.h" + + +long long int +llroundq (__float128 x) +{ + int64_t j0; + uint64_t i1, i0; + long long int result; + int sign; + + GET_FLT128_WORDS64 (i0, i1, x); + j0 = ((i0 >> 48) & 0x7fff) - 0x3fff; + sign = (i0 & 0x8000000000000000ULL) != 0 ? -1 : 1; + i0 &= 0x0000ffffffffffffLL; + i0 |= 0x0001000000000000LL; + + if (j0 < 48) + { + if (j0 < 0) + return j0 < -1 ? 0 : sign; + else + { + i0 += 0x0000800000000000LL >> j0; + result = i0 >> (48 - j0); + } + } + else if (j0 < (int32_t) (8 * sizeof (long long int)) - 1) + { + if (j0 >= 112) + result = ((long long int) i0 << (j0 - 48)) | (i1 << (j0 - 112)); + else + { + uint64_t j = i1 + (0x8000000000000000ULL >> (j0 - 48)); + if (j < i1) + ++i0; + + if (j0 == 48) + result = (long long int) i0; + else + result = ((long long int) i0 << (j0 - 48)) | (j >> (112 - j0)); + } + } + else + { + /* The number is too large. It is left implementation defined + what happens. */ + return (long long int) x; + } + + return sign * result; +} |