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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c197
1 files changed, 0 insertions, 197 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c b/sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c
deleted file mode 100644
index 4146e5c2d4..0000000000
--- a/sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c
+++ /dev/null
@@ -1,197 +0,0 @@
-/* Copyright (C) 1995-2017 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 <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). */
-
-
-/* When signs differ, the actual value is the difference between the
- significant double and the less significant double. Sometimes a
- bit can be lost when we borrow from the significant mantissa. */
-#define EXTRA_INTERNAL_PRECISION (7)
-
-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.ld = value;
-
- *is_neg = u.d[0].ieee.negative;
- *expt = (int) u.d[0].ieee.exponent - IEEE754_DOUBLE_BIAS;
-
- lo = ((long long) u.d[1].ieee.mantissa0 << 32) | u.d[1].ieee.mantissa1;
- hi = ((long long) u.d[0].ieee.mantissa0 << 32) | u.d[0].ieee.mantissa1;
-
- /* Hold 7 extra bits of precision in the mantissa. This allows
- the normalizing shifts below to prevent losing precision when
- the signs differ and the exponents are sufficiently far apart. */
- lo <<= EXTRA_INTERNAL_PRECISION;
-
- /* If the lower double is not a denormal or zero then set the hidden
- 53rd bit. */
- if (u.d[1].ieee.exponent != 0)
- lo |= 1ULL << (52 + EXTRA_INTERNAL_PRECISION);
- else
- lo = lo << 1;
-
- /* The lower double is normalized separately from the upper. We may
- need to adjust the lower manitissa to reflect this. */
- ediff = u.d[0].ieee.exponent - u.d[1].ieee.exponent - 53;
- if (ediff > 0)
- {
- if (ediff < 64)
- lo = lo >> ediff;
- else
- lo = 0;
- }
- else if (ediff < 0)
- lo = lo << -ediff;
-
- /* 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.d[0].ieee.negative != u.d[1].ieee.negative
- && lo != 0)
- {
- lo = (1ULL << (53 + EXTRA_INTERNAL_PRECISION)) - lo;
- if (hi == 0)
- {
- /* we have a borrow from the hidden bit, so shift left 1. */
- hi = 0x000ffffffffffffeLL | (lo >> (52 + EXTRA_INTERNAL_PRECISION));
- lo = 0x0fffffffffffffffLL & (lo << 1);
- (*expt)--;
- }
- else
- hi--;
- }
-#if BITS_PER_MP_LIMB == 32
- /* Combine the mantissas to be contiguous. */
- res_ptr[0] = lo >> EXTRA_INTERNAL_PRECISION;
- res_ptr[1] = (hi << (53 - 32)) | (lo >> (32 + EXTRA_INTERNAL_PRECISION));
- 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 >> EXTRA_INTERNAL_PRECISION);
- 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.d[0].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. We
- use DBL_MIN_EXP instead of LDBL_MIN_EXP below because the
- latter describes the properties of both parts together, but
- the exponent is computed from the high part only. */
- 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 = 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
- 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 = DBL_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;
-}
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