1 /* double mpz_get_d_2exp (signed long int *exp, mpz_t src). 2 3 Copyright 2001, 2003, 2004 Free Software Foundation, Inc. 4 5 This file is part of the GNU MP Library. 6 7 The GNU MP Library is free software; you can redistribute it and/or modify 8 it under the terms of the GNU Lesser General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or (at your 10 option) any later version. 11 12 The GNU MP Library is distributed in the hope that it will be useful, but 13 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 14 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 15 License for more details. 16 17 You should have received a copy of the GNU Lesser General Public License 18 along 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 24 double 25 mpz_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