1 /* mpz_divexact_ui -- exact division mpz by ulong. 2 3 Copyright 2001, 2002 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 23 void 24 mpz_divexact_ui (mpz_ptr dst, mpz_srcptr src, unsigned long divisor) 25 { 26 mp_size_t size, abs_size; 27 mp_ptr dst_ptr; 28 29 if (divisor == 0) 30 DIVIDE_BY_ZERO; 31 32 /* For nails don't try to be clever if d is bigger than a limb, just fake 33 up an mpz_t and go to the main mpz_divexact. */ 34 if (divisor > GMP_NUMB_MAX) 35 { 36 mp_limb_t dlimbs[2]; 37 mpz_t dz; 38 ALLOC(dz) = 2; 39 PTR(dz) = dlimbs; 40 mpz_set_ui (dz, divisor); 41 mpz_divexact (dst, src, dz); 42 return; 43 } 44 45 size = SIZ(src); 46 if (size == 0) 47 { 48 SIZ(dst) = 0; 49 return; 50 } 51 abs_size = ABS (size); 52 53 MPZ_REALLOC (dst, abs_size); 54 dst_ptr = PTR(dst); 55 56 MPN_DIVREM_OR_DIVEXACT_1 (dst_ptr, PTR(src), abs_size, (mp_limb_t) divisor); 57 abs_size -= (dst_ptr[abs_size-1] == 0); 58 SIZ(dst) = (size >= 0 ? abs_size : -abs_size); 59 } 60