diff options
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c')
| -rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c | 175 |
1 files changed, 0 insertions, 175 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c b/sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c deleted file mode 100644 index 18a2e67..0000000 --- a/sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c +++ /dev/null @@ -1,175 +0,0 @@ -/* Copyright (C) 1995,1996,1997,1998,1999,2002,2003,2006 - 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, write to the Free - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA - 02111-1307 USA. */ - -#include "gmp.h" -#include "gmp-impl.h" -#include "longlong.h" -#include <ieee754.h> -#include <float.h> -#include <math.h> -#include <stdlib.h> - -/* Convert a `long double' in IBM extended format to a multi-precision - integer representing the significand scaled up by its number of - bits (106 for long double) and an integral power of two (MPN - frexpl). */ - -mp_size_t -__mpn_extract_long_double (mp_ptr res_ptr, mp_size_t size, - int *expt, int *is_neg, - long double value) -{ - union ibm_extended_long_double u; - unsigned long long hi, lo; - int ediff; - u.d = value; - - *is_neg = u.ieee.negative; - *expt = (int) u.ieee.exponent - IBM_EXTENDED_LONG_DOUBLE_BIAS; - - lo = ((long long) u.ieee.mantissa2 << 32) | u.ieee.mantissa3; - hi = ((long long) u.ieee.mantissa0 << 32) | u.ieee.mantissa1; - /* If the lower double is not a denomal or zero then set the hidden - 53rd bit. */ - if (u.ieee.exponent2 > 0) - { - lo |= 1LL << 52; - - /* The lower double is normalized separately from the upper. We may - need to adjust the lower manitissa to reflect this. */ - ediff = u.ieee.exponent - u.ieee.exponent2; - if (ediff > 53) - lo = lo >> (ediff-53); - } - /* The high double may be rounded and the low double reflects the - difference between the long double and the rounded high double - value. This is indicated by a differnce between the signs of the - high and low doubles. */ - if ((u.ieee.negative != u.ieee.negative2) - && ((u.ieee.exponent2 != 0) && (lo != 0L))) - { - lo = (1ULL << 53) - lo; - if (hi == 0LL) - { - /* we have a borrow from the hidden bit, so shift left 1. */ - hi = 0x0ffffffffffffeLL | (lo >> 51); - lo = 0x1fffffffffffffLL & (lo << 1); - (*expt)--; - } - else - hi--; - } -#if BITS_PER_MP_LIMB == 32 - /* Combine the mantissas to be contiguous. */ - res_ptr[0] = lo; - res_ptr[1] = (hi << (53 - 32)) | (lo >> 32); - res_ptr[2] = hi >> 11; - res_ptr[3] = hi >> (32 + 11); - #define N 4 -#elif BITS_PER_MP_LIMB == 64 - /* Combine the two mantissas to be contiguous. */ - res_ptr[0] = (hi << 53) | lo; - res_ptr[1] = hi >> 11; - #define N 2 -#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 \ - - (LDBL_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[1] == 0 - && res_ptr[N - 2] == 0 && res_ptr[N - 1] == 0) /* Assumes N<=4. */ - /* 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 N == 2 - if (res_ptr[N - 1] != 0) - { - count_leading_zeros (cnt, res_ptr[N - 1]); - cnt -= NUM_LEADING_ZEROS; - res_ptr[N - 1] = res_ptr[N - 1] << cnt - | (res_ptr[0] >> (BITS_PER_MP_LIMB - cnt)); - res_ptr[0] <<= cnt; - *expt = LDBL_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 = LDBL_MIN_EXP - 1 - - (BITS_PER_MP_LIMB - NUM_LEADING_ZEROS) - cnt; - } -#else - int j, k, l; - - for (j = N - 1; j > 0; j--) - if (res_ptr[j] != 0) - break; - - count_leading_zeros (cnt, res_ptr[j]); - cnt -= NUM_LEADING_ZEROS; - l = N - 1 - j; - if (cnt < 0) - { - cnt += BITS_PER_MP_LIMB; - l--; - } - if (!cnt) - for (k = N - 1; k >= l; k--) - res_ptr[k] = res_ptr[k-l]; - else - { - for (k = N - 1; k > l; k--) - res_ptr[k] = res_ptr[k-l] << cnt - | res_ptr[k-l-1] >> (BITS_PER_MP_LIMB - cnt); - res_ptr[k--] = res_ptr[0] << cnt; - } - - for (; k >= 0; k--) - res_ptr[k] = 0; - *expt = LDBL_MIN_EXP - 1 - l * BITS_PER_MP_LIMB - cnt; -#endif - } - } - else - /* Add the implicit leading one bit for a normalized number. */ - res_ptr[N - 1] |= (mp_limb_t) 1 << (LDBL_MANT_DIG - 1 - - ((N - 1) * BITS_PER_MP_LIMB)); - - return N; -} |