1/* mpfr_ui_div -- divide a machine integer by a floating-point number 2 mpfr_si_div -- divide a machine number by a floating-point number 3 4Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc. 5Contributed by the Arenaire and Cacao projects, INRIA. 6 7This file is part of the GNU MPFR Library. 8 9The GNU MPFR Library is free software; you can redistribute it and/or modify 10it under the terms of the GNU Lesser General Public License as published by 11the Free Software Foundation; either version 3 of the License, or (at your 12option) any later version. 13 14The GNU MPFR Library is distributed in the hope that it will be useful, but 15WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 16or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 17License for more details. 18 19You should have received a copy of the GNU Lesser General Public License 20along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see 21http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 2251 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ 23 24 25#define MPFR_NEED_LONGLONG_H 26#include "mpfr-impl.h" 27 28int 29mpfr_ui_div (mpfr_ptr y, unsigned long int u, mpfr_srcptr x, mpfr_rnd_t rnd_mode) 30{ 31 mpfr_t uu; 32 mp_limb_t up[1]; 33 unsigned long cnt; 34 35 if (MPFR_UNLIKELY(MPFR_IS_SINGULAR(x))) 36 { 37 if (MPFR_IS_NAN(x)) 38 { 39 MPFR_SET_NAN(y); 40 MPFR_RET_NAN; 41 } 42 else if (MPFR_IS_INF(x)) /* u/Inf = 0 */ 43 { 44 MPFR_SET_ZERO(y); 45 MPFR_SET_SAME_SIGN(y,x); 46 MPFR_RET(0); 47 } 48 else /* u / 0 */ 49 { 50 MPFR_ASSERTD(MPFR_IS_ZERO(x)); 51 if (u) 52 { 53 /* u > 0, so y = sign(x) * Inf */ 54 MPFR_SET_SAME_SIGN(y, x); 55 MPFR_SET_INF(y); 56 MPFR_RET(0); 57 } 58 else 59 { 60 /* 0 / 0 */ 61 MPFR_SET_NAN(y); 62 MPFR_RET_NAN; 63 } 64 } 65 } 66 else if (MPFR_LIKELY(u != 0)) 67 { 68 MPFR_TMP_INIT1(up, uu, GMP_NUMB_BITS); 69 MPFR_ASSERTN(u == (mp_limb_t) u); 70 count_leading_zeros(cnt, (mp_limb_t) u); 71 up[0] = (mp_limb_t) u << cnt; 72 MPFR_SET_EXP (uu, GMP_NUMB_BITS - cnt); 73 return mpfr_div (y, uu, x, rnd_mode); 74 } 75 else /* u = 0, and x != 0 */ 76 { 77 MPFR_SET_ZERO(y); /* if u=0, then set y to 0 */ 78 MPFR_SET_SAME_SIGN(y, x); /* u considered as +0: sign(+0/x) = sign(x) */ 79 MPFR_RET(0); 80 } 81} 82 83 84int mpfr_si_div (mpfr_ptr y, long int u, mpfr_srcptr x,mpfr_rnd_t rnd_mode) 85{ 86 int res; 87 88 if (u >= 0) 89 res = mpfr_ui_div (y, u, x, rnd_mode); 90 else 91 { 92 res = -mpfr_ui_div (y, -u, x, MPFR_INVERT_RND(rnd_mode)); 93 MPFR_CHANGE_SIGN (y); 94 } 95 return res; 96} 97