1/* double mpz_get_d_2exp (signed long int *exp, mpz_t src). 2 3Copyright 2001, 2003, 2004 Free Software Foundation, Inc. 4 5This file is part of the GNU MP Library. 6 7The GNU MP Library is free software; you can redistribute it and/or modify 8it under the terms of the GNU Lesser General Public License as published by 9the Free Software Foundation; either version 3 of the License, or (at your 10option) any later version. 11 12The GNU MP Library is distributed in the hope that it will be useful, but 13WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 14or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 15License for more details. 16 17You should have received a copy of the GNU Lesser General Public License 18along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ 19 20#include "gmp.h" 21#include "gmp-impl.h" 22#include "longlong.h" 23 24double 25mpz_get_d_2exp (signed long int *exp2, mpz_srcptr src) 26{ 27 mp_size_t size, abs_size; 28 mp_srcptr ptr; 29 int cnt; 30 long exp; 31 32 size = SIZ(src); 33 if (UNLIKELY (size == 0)) 34 { 35 *exp2 = 0; 36 return 0.0; 37 } 38 39 ptr = PTR(src); 40 abs_size = ABS(size); 41 count_leading_zeros (cnt, ptr[abs_size - 1]); 42 exp = abs_size * GMP_NUMB_BITS - (cnt - GMP_NAIL_BITS); 43 *exp2 = exp; 44 return mpn_get_d (ptr, abs_size, size, -exp); 45} 46