1 /* Test mpz_[cft]div_[qr]_2exp. 2 3 Copyright 2001 Free Software Foundation, Inc. 4 5 This file is part of the GNU MP Library test suite. 6 7 The GNU MP Library test suite is free software; you can redistribute it 8 and/or modify it under the terms of the GNU General Public License as 9 published by the Free Software Foundation; either version 3 of the License, 10 or (at your option) any later version. 11 12 The GNU MP Library test suite is distributed in the hope that it will be 13 useful, but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 15 Public License for more details. 16 17 You should have received a copy of the GNU General Public License along with 18 the GNU MP Library test suite. If not, see http://www.gnu.org/licenses/. */ 19 20 #include <stdio.h> 21 #include <stdlib.h> 22 23 #include "gmp.h" 24 #include "gmp-impl.h" 25 #include "tests.h" 26 27 28 /* If the remainder is in the correct range and q*d+r is correct, then q 29 must have rounded correctly. */ 30 31 void 32 check_one (mpz_srcptr a, unsigned long d) 33 { 34 mpz_t q, r, p, d2exp; 35 int inplace; 36 37 mpz_init (d2exp); 38 mpz_init (q); 39 mpz_init (r); 40 mpz_init (p); 41 42 mpz_set_ui (d2exp, 1L); 43 mpz_mul_2exp (d2exp, d2exp, d); 44 45 #define INPLACE(fun,dst,src,d) \ 46 if (inplace) \ 47 { \ 48 mpz_set (dst, src); \ 49 fun (dst, dst, d); \ 50 } \ 51 else \ 52 fun (dst, src, d); 53 54 for (inplace = 0; inplace <= 1; inplace++) 55 { 56 INPLACE (mpz_fdiv_q_2exp, q, a, d); 57 INPLACE (mpz_fdiv_r_2exp, r, a, d); 58 59 mpz_mul_2exp (p, q, d); 60 mpz_add (p, p, r); 61 if (mpz_sgn (r) < 0 || mpz_cmp (r, d2exp) >= 0) 62 { 63 printf ("mpz_fdiv_r_2exp result out of range\n"); 64 goto error; 65 } 66 if (mpz_cmp (p, a) != 0) 67 { 68 printf ("mpz_fdiv_[qr]_2exp doesn't multiply back\n"); 69 goto error; 70 } 71 72 73 INPLACE (mpz_cdiv_q_2exp, q, a, d); 74 INPLACE (mpz_cdiv_r_2exp, r, a, d); 75 76 mpz_mul_2exp (p, q, d); 77 mpz_add (p, p, r); 78 if (mpz_sgn (r) > 0 || mpz_cmpabs (r, d2exp) >= 0) 79 { 80 printf ("mpz_cdiv_r_2exp result out of range\n"); 81 goto error; 82 } 83 if (mpz_cmp (p, a) != 0) 84 { 85 printf ("mpz_cdiv_[qr]_2exp doesn't multiply back\n"); 86 goto error; 87 } 88 89 90 INPLACE (mpz_tdiv_q_2exp, q, a, d); 91 INPLACE (mpz_tdiv_r_2exp, r, a, d); 92 93 mpz_mul_2exp (p, q, d); 94 mpz_add (p, p, r); 95 if (mpz_sgn (r) != 0 && mpz_sgn (r) != mpz_sgn (a)) 96 { 97 printf ("mpz_tdiv_r_2exp result wrong sign\n"); 98 goto error; 99 } 100 if (mpz_cmpabs (r, d2exp) >= 0) 101 { 102 printf ("mpz_tdiv_r_2exp result out of range\n"); 103 goto error; 104 } 105 if (mpz_cmp (p, a) != 0) 106 { 107 printf ("mpz_tdiv_[qr]_2exp doesn't multiply back\n"); 108 goto error; 109 } 110 } 111 112 mpz_clear (d2exp); 113 mpz_clear (q); 114 mpz_clear (r); 115 mpz_clear (p); 116 return; 117 118 119 error: 120 mpz_trace ("a", a); 121 printf ("d=%lu\n", d); 122 mpz_trace ("q", q); 123 mpz_trace ("r", r); 124 mpz_trace ("p", p); 125 126 mp_trace_base = -16; 127 mpz_trace ("a", a); 128 printf ("d=0x%lX\n", d); 129 mpz_trace ("q", q); 130 mpz_trace ("r", r); 131 mpz_trace ("p", p); 132 133 abort (); 134 } 135 136 137 void 138 check_all (mpz_ptr a, unsigned long d) 139 { 140 check_one (a, d); 141 mpz_neg (a, a); 142 check_one (a, d); 143 } 144 145 146 void 147 check_various (void) 148 { 149 static const unsigned long table[] = { 150 0, 1, 2, 3, 4, 5, 151 GMP_NUMB_BITS-1, GMP_NUMB_BITS, GMP_NUMB_BITS+1, 152 2*GMP_NUMB_BITS-1, 2*GMP_NUMB_BITS, 2*GMP_NUMB_BITS+1, 153 3*GMP_NUMB_BITS-1, 3*GMP_NUMB_BITS, 3*GMP_NUMB_BITS+1, 154 4*GMP_NUMB_BITS-1, 4*GMP_NUMB_BITS, 4*GMP_NUMB_BITS+1 155 }; 156 157 int i, j; 158 unsigned long n, d; 159 mpz_t a; 160 161 mpz_init (a); 162 163 /* a==0, and various d */ 164 mpz_set_ui (a, 0L); 165 for (i = 0; i < numberof (table); i++) 166 check_one (a, table[i]); 167 168 /* a==2^n, and various d */ 169 for (i = 0; i < numberof (table); i++) 170 { 171 n = table[i]; 172 mpz_set_ui (a, 1L); 173 mpz_mul_2exp (a, a, n); 174 175 for (j = 0; j < numberof (table); j++) 176 { 177 d = table[j]; 178 check_all (a, d); 179 } 180 } 181 182 mpz_clear (a); 183 } 184 185 186 void 187 check_random (int argc, char *argv[]) 188 { 189 gmp_randstate_ptr rands = RANDS; 190 int reps = 100; 191 mpz_t a; 192 unsigned long d; 193 int i; 194 195 if (argc == 2) 196 reps = atoi (argv[1]); 197 198 mpz_init (a); 199 200 for (i = 0; i < reps; i++) 201 { 202 /* exponentially within 2 to 257 bits */ 203 mpz_erandomb (a, rands, urandom () % 8 + 2); 204 205 d = urandom () % 256; 206 207 check_all (a, d); 208 } 209 210 mpz_clear (a); 211 } 212 213 214 int 215 main (int argc, char *argv[]) 216 { 217 tests_start (); 218 219 check_various (); 220 check_random (argc, argv); 221 222 tests_end (); 223 exit (0); 224 } 225