diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/dbl2mpn.c')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/dbl2mpn.c | 107 |
1 files changed, 0 insertions, 107 deletions
diff --git a/sysdeps/ieee754/dbl-64/dbl2mpn.c b/sysdeps/ieee754/dbl-64/dbl2mpn.c deleted file mode 100644 index 8294dc26ed..0000000000 --- a/sysdeps/ieee754/dbl-64/dbl2mpn.c +++ /dev/null @@ -1,107 +0,0 @@ -/* Copyright (C) 1993-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - 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 - <http://www.gnu.org/licenses/>. */ - -#include "gmp.h" -#include "gmp-impl.h" -#include "longlong.h" -#include <ieee754.h> -#include <float.h> -#include <stdlib.h> - -/* Convert a `double' in IEEE754 standard double-precision format to a - multi-precision integer representing the significand scaled up by its - number of bits (52 for double) and an integral power of two (MPN frexp). */ - -mp_size_t -__mpn_extract_double (mp_ptr res_ptr, mp_size_t size, - int *expt, int *is_neg, - double value) -{ - union ieee754_double u; - u.d = value; - - *is_neg = u.ieee.negative; - *expt = (int) u.ieee.exponent - IEEE754_DOUBLE_BIAS; - -#if BITS_PER_MP_LIMB == 32 - res_ptr[0] = u.ieee.mantissa1; /* Low-order 32 bits of fraction. */ - res_ptr[1] = u.ieee.mantissa0; /* High-order 20 bits. */ - # define N 2 -#elif BITS_PER_MP_LIMB == 64 - /* Hopefully the compiler will combine the two bitfield extracts - and this composition into just the original quadword extract. */ - res_ptr[0] = ((mp_limb_t) u.ieee.mantissa0 << 32) | u.ieee.mantissa1; - # define N 1 -#else - # error "mp_limb size " BITS_PER_MP_LIMB "not accounted for" -#endif -/* The format does not fill the last limb. There are some zeros. */ -#define NUM_LEADING_ZEROS (BITS_PER_MP_LIMB \ - - (DBL_MANT_DIG - ((N - 1) * BITS_PER_MP_LIMB))) - - if (u.ieee.exponent == 0) - { - /* A biased exponent of zero is a special case. - Either it is a zero or it is a denormal number. */ - if (res_ptr[0] == 0 && res_ptr[N - 1] == 0) /* Assumes N<=2. */ - /* It's zero. */ - *expt = 0; - else - { - /* It is a denormal number, meaning it has no implicit leading - one bit, and its exponent is in fact the format minimum. */ - int cnt; - - if (res_ptr[N - 1] != 0) - { - count_leading_zeros (cnt, res_ptr[N - 1]); - cnt -= NUM_LEADING_ZEROS; -#if N == 2 - res_ptr[N - 1] = res_ptr[1] << cnt - | (N - 1) - * (res_ptr[0] >> (BITS_PER_MP_LIMB - cnt)); - res_ptr[0] <<= cnt; -#else - res_ptr[N - 1] <<= cnt; -#endif - *expt = DBL_MIN_EXP - 1 - cnt; - } - else - { - count_leading_zeros (cnt, res_ptr[0]); - if (cnt >= NUM_LEADING_ZEROS) - { - res_ptr[N - 1] = res_ptr[0] << (cnt - NUM_LEADING_ZEROS); - res_ptr[0] = 0; - } - else - { - res_ptr[N - 1] = res_ptr[0] >> (NUM_LEADING_ZEROS - cnt); - res_ptr[0] <<= BITS_PER_MP_LIMB - (NUM_LEADING_ZEROS - cnt); - } - *expt = DBL_MIN_EXP - 1 - - (BITS_PER_MP_LIMB - NUM_LEADING_ZEROS) - cnt; - } - } - } - else - /* Add the implicit leading one bit for a normalized number. */ - res_ptr[N - 1] |= (mp_limb_t) 1 << (DBL_MANT_DIG - 1 - - ((N - 1) * BITS_PER_MP_LIMB)); - - return N; -} |