X-Git-Url: https://oss.titaniummirror.com/gitweb/?a=blobdiff_plain;f=mpfr%2Fset.c;fp=mpfr%2Fset.c;h=85618e4aaa9b9342f80557306bbf08a89689e6d6;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/mpfr/set.c b/mpfr/set.c new file mode 100644 index 00000000..85618e4a --- /dev/null +++ b/mpfr/set.c @@ -0,0 +1,81 @@ +/* mpfr_set -- copy of a floating-point number + +Copyright 1999, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. +Contributed by the Arenaire and Cacao 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 2.1 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.LIB. If not, write to +the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, +MA 02110-1301, USA. */ + +#include "mpfr-impl.h" + +/* set a to abs(b) * signb: a=b when signb = SIGN(b), a=abs(b) when signb=1 */ +int +mpfr_set4 (mpfr_ptr a, mpfr_srcptr b, mp_rnd_t rnd_mode, int signb) +{ + /* Sign is ALWAYS copied */ + MPFR_SET_SIGN (a, signb); + + /* Exponent is also always copied since if the number is singular, + the exponent field determined the number. + Can't use MPFR_SET_EXP since the exponent may be singular */ + MPFR_EXP (a) = MPFR_EXP (b); + + if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (b))) + { + /* MPFR_SET_NAN, MPFR_SET_ZERO and MPFR_SET_INF are useless + since MPFR_EXP (a) = MPFR_EXP (b) does the job */ + if (MPFR_IS_NAN (b)) + MPFR_RET_NAN; + else + MPFR_RET (0); + } + else if (MPFR_LIKELY (MPFR_PREC (b) == MPFR_PREC (a))) + { + /* Same precision and b is not singular: + * just copy the mantissa, and set the exponent and the sign + * The result is exact. */ + MPN_COPY (MPFR_MANT (a), MPFR_MANT (b), + (MPFR_PREC (b) + BITS_PER_MP_LIMB-1)/BITS_PER_MP_LIMB); + MPFR_RET (0); + } + else + { + int inex; + + /* Else Round B inside a */ + MPFR_RNDRAW (inex, a, MPFR_MANT (b), MPFR_PREC (b), rnd_mode, signb, + if (MPFR_UNLIKELY ( ++MPFR_EXP (a) > __gmpfr_emax)) + return mpfr_overflow (a, rnd_mode, signb) ); + MPFR_RET (inex); + } +} + +/* Set a to b */ +#undef mpfr_set +int +mpfr_set (mpfr_ptr a, mpfr_srcptr b, mp_rnd_t rnd_mode) +{ + return mpfr_set4 (a, b, rnd_mode, MPFR_SIGN (b)); +} + +/* Set a to |b| */ +#undef mpfr_abs +int +mpfr_abs (mpfr_ptr a, mpfr_srcptr b, mp_rnd_t rnd_mode) +{ + return mpfr_set4 (a, b, rnd_mode, MPFR_SIGN_POS); +}