glibc/sysdeps/ieee754/ldbl2mpn.c

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Wed Feb 21 02:25:07 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> * Rules (others): Depend on $(extra-objs), $(install-lib), $(install-bin), $(install-sbin), in object directory. * Makeconfig (link-libc): Don't pass -rpath option with default path, since ld.so should use the same default. * Makerules (build-shlib): Likewise. * Makerules (make-target-directory): Use mkinstalldirs. * sysdeps/mach/i386/sysdep.h: Include unix/i386/sysdep.h to redefine ENTRY et al. * sysdeps/unix/sysv/linux/i386/sysdep.h (NO_UNDERSCORES, ENTRY): Macros removed. The code in unix/i386/sysdep.h should now suffice. * sysdeps/unix/i386/sysdep.h (ALIGNARG): New macro, defns for [HAVE_ELF] and not. (ENTRY): Use it in .align directive. (CALL_MCOUNT): New macro, empty unless [PROF]. (ENTRY): Do CALL_MCOUNT just after the label. * Makeconfig (CPPFLAGS-.po): New variable, use -DPROF so assembly code can call mcount. Tue Feb 20 23:05:16 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> * time/private.h, time/zdump.c, time/zic.c: Updated verbatim from ADO; translation markings are now integrated in his distribution. * stdlib/strtod.c (round_and_return): Add missing (mp_limb) 1 cast. * po: New directory where `LANG.po' files for message translations will reside. * po/SYS_libc.pot: New file, template of message strings as in source. * MakeTAGS: New rules to build po/SYS_libc.pot automatically from the source using xgettext. * Makerules ($(..)po/%.pot): New rule. * manual/Makefile (../po/manual.pot): New target, make it empty. * sysdeps/unix/bsd/alarm.c: Moved to sysdeps/unix/alarm.c. * sysdeps/unix/bsd/nice.c: Moved to sysdeps/unix/nice.c. * sysdeps/unix/bsd/stime.c: Moved to sysdeps/unix/stime.c. * sysdeps/unix/bsd/time.c: Moved to sysdeps/unix/time.c. * sysdeps/unix/bsd/utime.c: Moved to sysdeps/unix/utime.c.
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/* Copyright (C) 1995, 1996 Free Software Foundation, Inc.
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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 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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include "gmp.h"
#include "gmp-impl.h"
#include "longlong.h"
#include "ieee754.h"
#include <float.h>
#include <stdlib.h>
/* Convert a `long double' in IEEE854 standard double-precision format to a
multi-precision integer representing the significand scaled up by its
number of bits (64 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 ieee854_long_double u;
u.d = value;
*is_neg = u.ieee.negative;
*expt = (int) u.ieee.exponent - IEEE854_LONG_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 32 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. */
Wed Feb 21 02:25:07 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> * Rules (others): Depend on $(extra-objs), $(install-lib), $(install-bin), $(install-sbin), in object directory. * Makeconfig (link-libc): Don't pass -rpath option with default path, since ld.so should use the same default. * Makerules (build-shlib): Likewise. * Makerules (make-target-directory): Use mkinstalldirs. * sysdeps/mach/i386/sysdep.h: Include unix/i386/sysdep.h to redefine ENTRY et al. * sysdeps/unix/sysv/linux/i386/sysdep.h (NO_UNDERSCORES, ENTRY): Macros removed. The code in unix/i386/sysdep.h should now suffice. * sysdeps/unix/i386/sysdep.h (ALIGNARG): New macro, defns for [HAVE_ELF] and not. (ENTRY): Use it in .align directive. (CALL_MCOUNT): New macro, empty unless [PROF]. (ENTRY): Do CALL_MCOUNT just after the label. * Makeconfig (CPPFLAGS-.po): New variable, use -DPROF so assembly code can call mcount. Tue Feb 20 23:05:16 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> * time/private.h, time/zdump.c, time/zic.c: Updated verbatim from ADO; translation markings are now integrated in his distribution. * stdlib/strtod.c (round_and_return): Add missing (mp_limb) 1 cast. * po: New directory where `LANG.po' files for message translations will reside. * po/SYS_libc.pot: New file, template of message strings as in source. * MakeTAGS: New rules to build po/SYS_libc.pot automatically from the source using xgettext. * Makerules ($(..)po/%.pot): New rule. * manual/Makefile (../po/manual.pot): New target, make it empty. * sysdeps/unix/bsd/alarm.c: Moved to sysdeps/unix/alarm.c. * sysdeps/unix/bsd/nice.c: Moved to sysdeps/unix/nice.c. * sysdeps/unix/bsd/stime.c: Moved to sysdeps/unix/stime.c. * sysdeps/unix/bsd/time.c: Moved to sysdeps/unix/time.c. * sysdeps/unix/bsd/utime.c: Moved to sysdeps/unix/utime.c.
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res_ptr[0] = ((unsigned long int) u.ieee.mantissa0 << 32) | u.ieee.mantissa1;
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#define N 1
#else
#error "mp_limb size " BITS_PER_MP_LIMB "not accounted for"
#endif
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;
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if (res_ptr[N - 1] != 0)
{
count_leading_zeros (cnt, res_ptr[N - 1]);
if (cnt != 0)
{
#if N == 2
res_ptr[N - 1] = res_ptr[N - 1] << cnt
| (res_ptr[0] >> (BITS_PER_MP_LIMB - cnt));
res_ptr[0] <<= cnt;
#else
res_ptr[N - 1] <<= cnt;
#endif
}
*expt = LDBL_MIN_EXP - 1 - cnt;
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}
else
{
count_leading_zeros (cnt, res_ptr[0]);
res_ptr[N - 1] = res_ptr[0] << cnt;
res_ptr[0] = 0;
*expt = LDBL_MIN_EXP - 1 - BITS_PER_MP_LIMB - cnt;
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}
}
}
return N;
}