1/* Test mpn_gcdext_1. 2 3Copyright 2019 Free Software Foundation, Inc. 4 5This file is part of the GNU MP Library test suite. 6 7The GNU MP Library test suite is free software; you can redistribute it 8and/or modify it under the terms of the GNU General Public License as 9published by the Free Software Foundation; either version 3 of the License, 10or (at your option) any later version. 11 12The GNU MP Library test suite is distributed in the hope that it will be 13useful, but WITHOUT ANY WARRANTY; without even the implied warranty of 14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 15Public License for more details. 16 17You should have received a copy of the GNU General Public License along with 18the GNU MP Library test suite. If not, see https://www.gnu.org/licenses/. */ 19 20#include <stdio.h> 21#include <stdlib.h> 22 23#include "gmp-impl.h" 24#include "tests.h" 25 26#ifndef COUNT 27#define COUNT 250000 28#endif 29 30static void 31set_signed_limb (mpz_t r, mp_limb_signed_t x) 32{ 33 mpz_t t; 34 mp_limb_t abs_x = ABS_CAST(mp_limb_t, x); 35 mpz_set (r, mpz_roinit_n (t, &abs_x, 1)); 36 if (x < 0) 37 mpz_neg (r, r); 38} 39 40static void 41one_test (mp_limb_t a, mp_limb_t b) 42{ 43 mp_limb_signed_t s, t; 44 mp_limb_t g; 45 46 g = mpn_gcdext_1 (&s, &t, a, b); 47 48 if (g > 0) 49 { 50 mpz_t d, sz, tz, tmp; 51 52 mpz_init (d); 53 mpz_init (sz); 54 mpz_init (tz); 55 56 set_signed_limb (sz, s); 57 set_signed_limb (tz, t); 58 59 mpz_mul (d, mpz_roinit_n (tmp, &a, 1), sz); 60 mpz_addmul (d, mpz_roinit_n (tmp, &b, 1), tz); 61 62 if (mpz_cmp (d, mpz_roinit_n (tmp, &g, 1)) == 0 63 && a % g == 0 && b % g == 0) 64 { 65 mp_limb_t a_div_g = a / g; 66 mp_limb_t b_div_g = b / g; 67 mp_limb_t abs_s = ABS_CAST(mp_limb_t, s); 68 mp_limb_t abs_t = ABS_CAST(mp_limb_t, t); 69 mpz_mul_ui (sz, sz, 2); 70 mpz_mul_ui (tz, tz, 2); 71 if ((abs_s == 1 || mpz_cmpabs (sz, mpz_roinit_n (tmp, &b_div_g, 1)) < 0) 72 && (abs_t == 1 || mpz_cmpabs (tz, mpz_roinit_n (tmp, &a_div_g, 1)) < 0)) 73 { 74 mpz_clear (d); 75 mpz_clear (sz); 76 mpz_clear (tz); 77 78 return; 79 } 80 } 81 } 82 gmp_fprintf (stderr, 83 "gcdext_1 (0x%Mx, 0x%Mx) failed, got: g = 0x%Mx, s = %s0x%Mx, t = %s0x%Mx\n", 84 a, b, g, 85 s < 0 ? "-" : "", ABS_CAST(mp_limb_t, s), 86 t < 0 ? "-" : "", ABS_CAST(mp_limb_t, t)); 87 abort(); 88} 89 90int 91main (int argc, char **argv) 92{ 93 mpz_t a, b; 94 int count = COUNT; 95 int test; 96 gmp_randstate_ptr rands; 97 98 TESTS_REPS (count, argv, argc); 99 100 tests_start (); 101 rands = RANDS; 102 103 mpz_init (a); 104 mpz_init (b); 105 for (test = 0; test < count; test++) 106 { 107 mp_limb_t al, bl; 108 mp_bitcnt_t asize = 1 + gmp_urandomm_ui(rands, GMP_NUMB_BITS); 109 mp_bitcnt_t bsize = 1 + gmp_urandomm_ui(rands, GMP_NUMB_BITS); 110 if (test & 1) 111 { 112 mpz_urandomb (a, rands, asize); 113 mpz_urandomb (b, rands, bsize); 114 } 115 else 116 { 117 mpz_rrandomb (a, rands, asize); 118 mpz_rrandomb (b, rands, bsize); 119 } 120 121 al = mpz_getlimbn (a, 0); 122 bl = mpz_getlimbn (b, 0); 123 al += (al == 0); 124 bl += (bl == 0); 125 126 one_test (al, bl); 127 } 128 129 mpz_clear (a); 130 mpz_clear (b); 131 132 tests_end (); 133 return 0; 134} 135