diff options
author | vlefevre <vlefevre@280ebfd0-de03-0410-8827-d642c229c3f4> | 2010-08-17 09:10:13 +0000 |
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committer | vlefevre <vlefevre@280ebfd0-de03-0410-8827-d642c229c3f4> | 2010-08-17 09:10:13 +0000 |
commit | c9583bdfe064e1069828e518533f7bc29a8fdddb (patch) | |
tree | 2400842d4095628b8486fbeabaf7bc7b8af4ed02 /src/set_f.c | |
parent | 50ac5b5985174201c7fa6e20496cd2b096107001 (diff) | |
download | mpfr-c9583bdfe064e1069828e518533f7bc29a8fdddb.tar.gz |
Source reorganization. In short:
* Added directories and moved related files into them:
- src for the MPFR source files (to build the library).
- doc for documentation files (except INSTALL, README...).
- tools for various tools (scripts) and mbench.
- tune for tuneup-related source files.
- other for other source files (not distributed in tarballs).
Existing directories:
- tests for the source files of the test suite (make check).
- examples for examples.
- m4 for m4 files.
* Renamed configure.in to configure.ac.
* Added/updated Makefile.am files where needed.
* Updated acinclude.m4 and configure.ac (AC_CONFIG_FILES line).
* Updated the documentation (INSTALL, README, doc/README.dev and
doc/mpfr.texi).
* Updated NEWS and TODO.
* Updated the scripts now in tools.
The following script was used:
#!/usr/bin/env zsh
svn mkdir doc other src tools tune
svn mv ${${(M)$(sed -n '/libmpfr_la_SOURCES/,/[^\]$/p' \
Makefile.am):#*.[ch]}:#get_patches.c} mparam_h.in \
round_raw_generic.c jyn_asympt.c src
svn mv mbench check_inits_clears coverage get_patches.sh mpfrlint \
nightly-test update-patchv update-version tools
svn mv bidimensional_sample.c speed.c tuneup.c tune
svn mv *.{c,h} other
svn mv FAQ.html README.dev algorithm* faq.xsl fdl.texi mpfr.texi \
update-faq doc
svn mv configure.in configure.ac
svn cp Makefile.am src/Makefile.am
svn rm replace_all
[Modifying some files, see above]
svn add doc/Makefile.am
svn add tune/Makefile.am
git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@7087 280ebfd0-de03-0410-8827-d642c229c3f4
Diffstat (limited to 'src/set_f.c')
-rw-r--r-- | src/set_f.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/src/set_f.c b/src/set_f.c new file mode 100644 index 000000000..bbd6e5efd --- /dev/null +++ b/src/set_f.c @@ -0,0 +1,99 @@ +/* mpfr_set_f -- set a MPFR number from a GNU MPF number + +Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. +Contributed by the Arenaire and Caramel projects, INRIA. + +This file is part of the GNU MPFR Library. + +The GNU MPFR 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 3 of the License, or (at your +option) any later version. + +The GNU MPFR 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 MPFR Library; see the file COPYING.LESSER. If not, see +http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., +51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ + +#define MPFR_NEED_LONGLONG_H +#include "mpfr-impl.h" + +int +mpfr_set_f (mpfr_ptr y, mpf_srcptr x, mpfr_rnd_t rnd_mode) +{ + mp_limb_t *my, *mx, *tmp; + unsigned long cnt, sx, sy; + int inexact, carry = 0; + MPFR_TMP_DECL(marker); + + sx = ABS(SIZ(x)); /* number of limbs of the mantissa of x */ + + if (sx == 0) /* x is zero */ + { + MPFR_SET_ZERO(y); + MPFR_SET_POS(y); + return 0; /* 0 is exact */ + } + + if (SIZ(x) * MPFR_FROM_SIGN_TO_INT(MPFR_SIGN(y)) < 0) + MPFR_CHANGE_SIGN (y); + + sy = 1 + (MPFR_PREC(y) - 1) / GMP_NUMB_BITS; + my = MPFR_MANT(y); + mx = PTR(x); + + count_leading_zeros(cnt, mx[sx - 1]); + + if (sy <= sx) /* we may have to round even when sy = sx */ + { + unsigned long xprec = sx * GMP_NUMB_BITS; + + MPFR_TMP_MARK(marker); + tmp = (mp_limb_t*) MPFR_TMP_ALLOC(sx * BYTES_PER_MP_LIMB); + if (cnt) + mpn_lshift (tmp, mx, sx, cnt); + else + /* FIXME: we may avoid the copy here, and directly call mpfr_round_raw + on mx instead of tmp */ + MPN_COPY (tmp, mx, sx); + carry = mpfr_round_raw (my, tmp, xprec, (SIZ(x) < 0), MPFR_PREC(y), + rnd_mode, &inexact); + if (MPFR_UNLIKELY(carry)) /* result is a power of two */ + my[sy - 1] = MPFR_LIMB_HIGHBIT; + MPFR_TMP_FREE(marker); + } + else + { + if (cnt) + mpn_lshift (my + sy - sx, mx, sx, cnt); + else + MPN_COPY (my + sy - sx, mx, sx); + MPN_ZERO(my, sy - sx); + /* no rounding necessary, since y has a larger mantissa */ + inexact = 0; + } + + /* warning: EXP(x) * GMP_NUMB_BITS may exceed the maximal exponent */ + if (EXP(x) > 1 + (__gmpfr_emax - 1) / GMP_NUMB_BITS) + { + /* EXP(x) >= 2 + floor((__gmpfr_emax-1)/GMP_NUMB_BITS) + EXP(x) >= 2 + (__gmpfr_emax - GMP_NUMB_BITS) / GMP_NUMB_BITS + >= 1 + __gmpfr_emax / GMP_NUMB_BITS + EXP(x) * GMP_NUMB_BITS >= __gmpfr_emax + GMP_NUMB_BITS + Since 0 <= cnt <= GMP_NUMB_BITS-1, and 0 <= carry <= 1, + we have then EXP(x) * GMP_NUMB_BITS - cnt + carry > __gmpfr_emax */ + return mpfr_overflow (y, rnd_mode, MPFR_SIGN (y)); + } + else + { + /* Do not use MPFR_SET_EXP as the exponent may be out of range. */ + MPFR_EXP (y) = EXP (x) * GMP_NUMB_BITS - (mpfr_exp_t) cnt + carry; + } + + return mpfr_check_range (y, inexact, rnd_mode); +} |