1/* Test mpz_set_d and mpz_init_set_d. 2 3Copyright 2000-2003, 2006 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#include "gmp-impl.h" 23#include "tests.h" 24 25 26void 27check_data (void) 28{ 29 static const struct { 30 double d; 31 mp_size_t want_size; 32 mp_limb_t want_data[2]; 33 } data[] = { 34 35 { 0.0, 0 }, 36 { 1.0, 1, { 1 } }, 37 { -1.0, -1, { 1 } }, 38 39 { 123.0, 1, { 123 } }, 40 { -123.0, -1, { 123 } }, 41 42 { 1e-1, 0, { 0 } }, 43 { -1e-1, 0, { 0 } }, 44 { 2.328306436538696e-10, 0, { 0 } }, 45 { -2.328306436538696e-10, 0, { 0 } }, 46 { 5.421010862427522e-20, 0, { 0 } }, 47 { -5.421010862427522e-20, 0, { 0 } }, 48 { 2.938735877055719e-39, 0, { 0 } }, 49 { -2.938735877055719e-39, 0, { 0 } }, 50 }; 51 52 mpz_t z; 53 int i; 54 55 for (i = 0; i < numberof (data); i++) 56 { 57 mpz_init (z); 58 mpz_set_d (z, data[i].d); 59 MPZ_CHECK_FORMAT (z); 60 if (z->_mp_size != data[i].want_size 61 || refmpn_cmp_allowzero (z->_mp_d, data[i].want_data, 62 ABS (data[i].want_size)) != 0) 63 { 64 printf ("mpz_set_d wrong on data[%d]\n", i); 65 bad: 66 d_trace (" d ", data[i].d); 67 printf (" got size %ld\n", (long) z->_mp_size); 68 printf (" want size %ld\n", (long) data[i].want_size); 69 mpn_trace (" got z", z->_mp_d, z->_mp_size); 70 mpn_trace (" want z", data[i].want_data, data[i].want_size); 71 abort(); 72 } 73 mpz_clear (z); 74 75 mpz_init_set_d (z, data[i].d); 76 MPZ_CHECK_FORMAT (z); 77 if (z->_mp_size != data[i].want_size 78 || refmpn_cmp_allowzero (z->_mp_d, data[i].want_data, 79 ABS (data[i].want_size)) != 0) 80 { 81 printf ("mpz_init_set_d wrong on data[%d]\n", i); 82 goto bad; 83 } 84 mpz_clear (z); 85 } 86} 87 88/* Try mpz_set_d on values 2^i+1, while such a value fits a double. */ 89void 90check_2n_plus_1 (void) 91{ 92 volatile double p, d, diff; 93 mpz_t want, got; 94 int i; 95 96 mpz_init (want); 97 mpz_init (got); 98 99 p = 1.0; 100 mpz_set_ui (want, 2L); /* gives 3 on first step */ 101 102 for (i = 1; i < 500; i++) 103 { 104 mpz_mul_2exp (want, want, 1L); 105 mpz_sub_ui (want, want, 1L); /* want = 2^i+1 */ 106 107 p *= 2.0; /* p = 2^i */ 108 d = p + 1.0; 109 diff = d - p; 110 if (diff != 1.0) 111 break; /* rounding occurred, stop now */ 112 113 mpz_set_d (got, d); 114 MPZ_CHECK_FORMAT (got); 115 if (mpz_cmp (got, want) != 0) 116 { 117 printf ("mpz_set_d wrong on 2^%d+1\n", i); 118 d_trace (" d ", d); 119 mpz_trace (" got ", got); 120 mpz_trace (" want ", want); 121 abort (); 122 } 123 } 124 125 mpz_clear (want); 126 mpz_clear (got); 127} 128 129int 130main (void) 131{ 132 tests_start (); 133 134 check_data (); 135 check_2n_plus_1 (); 136 137 tests_end (); 138 exit (0); 139} 140