1 // Copyright John Maddock 2015.
3 // Use, modification and distribution are subject to the
4 // Boost Software License, Version 1.0.
5 // (See accompanying file LICENSE_1_0.txt
6 // or copy at http://www.boost.org/LICENSE_1_0.txt)
9 #define _SCL_SECURE_NO_WARNINGS
12 #include <boost/multiprecision/cpp_int.hpp>
14 #include <boost/algorithm/string/case_conv.hpp>
15 #include <boost/random/mersenne_twister.hpp>
16 #include <boost/random/uniform_int.hpp>
22 #pragma warning(disable : 4127)
30 template <unsigned MinBits, unsigned MaxBits, boost::multiprecision::cpp_integer_type SignType, boost::multiprecision::cpp_int_check_type Checked, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
31 struct unchecked_type<boost::multiprecision::number<boost::multiprecision::cpp_int_backend<MinBits, MaxBits, SignType, Checked, Allocator>, ExpressionTemplates> >
33 typedef boost::multiprecision::number<boost::multiprecision::cpp_int_backend<MinBits, MaxBits, SignType, boost::multiprecision::unchecked, Allocator>, ExpressionTemplates> type;
39 typedef typename unchecked_type<T>::type unchecked_T;
41 static const unsigned limbs = std::numeric_limits<T>::is_specialized && std::numeric_limits<T>::is_bounded ? std::numeric_limits<T>::digits / std::numeric_limits<unsigned>::digits + 3 : 20;
43 static boost::random::uniform_int_distribution<unsigned> ui(0, limbs);
44 static boost::random::mt19937 gen;
45 unchecked_T val = gen();
46 unsigned lim = ui(gen);
47 for (unsigned i = 0; i < lim; ++i)
56 void test_round_trip_neg(T val, const boost::mpl::true_&)
58 // Try some negative values:
59 std::vector<unsigned char> cv;
62 export_bits(val, std::back_inserter(cv), 8, false);
63 import_bits(newval, cv.begin(), cv.end(), 8, false);
64 BOOST_CHECK_EQUAL(-val, newval);
68 void test_round_trip_neg(const T&, const boost::mpl::false_&)
73 void test_round_trip(T val)
75 std::vector<unsigned char> cv;
76 export_bits(val, std::back_inserter(cv), 8);
78 import_bits(newval, cv.begin(), cv.end());
79 BOOST_CHECK_EQUAL(val, newval);
80 // Should get the same value if we reverse the bytes:
81 std::reverse(cv.begin(), cv.end());
83 import_bits(newval, cv.begin(), cv.end(), 8, false);
84 BOOST_CHECK_EQUAL(val, newval);
85 // Also try importing via pointers as these may memcpy:
87 import_bits(newval, &cv[0], &cv[0] + cv.size(), 8, false);
88 BOOST_CHECK_EQUAL(val, newval);
91 export_bits(val, std::back_inserter(cv), 8, false);
92 import_bits(newval, cv.begin(), cv.end(), 8, false);
93 BOOST_CHECK_EQUAL(val, newval);
94 std::reverse(cv.begin(), cv.end());
96 import_bits(newval, cv.begin(), cv.end(), 8, true);
97 BOOST_CHECK_EQUAL(val, newval);
99 std::vector<boost::uintmax_t> bv;
100 export_bits(val, std::back_inserter(bv), std::numeric_limits<boost::uintmax_t>::digits);
101 import_bits(newval, bv.begin(), bv.end());
102 BOOST_CHECK_EQUAL(val, newval);
103 // Should get the same value if we reverse the values:
104 std::reverse(bv.begin(), bv.end());
106 import_bits(newval, bv.begin(), bv.end(), std::numeric_limits<boost::uintmax_t>::digits, false);
107 BOOST_CHECK_EQUAL(val, newval);
108 // Also try importing via pointers as these may memcpy:
110 import_bits(newval, &bv[0], &bv[0] + bv.size(), std::numeric_limits<boost::uintmax_t>::digits, false);
111 BOOST_CHECK_EQUAL(val, newval);
114 export_bits(val, std::back_inserter(bv), std::numeric_limits<boost::uintmax_t>::digits, false);
115 import_bits(newval, bv.begin(), bv.end(), std::numeric_limits<boost::uintmax_t>::digits, false);
116 BOOST_CHECK_EQUAL(val, newval);
118 // Try with an unconventional number of bits, to model some machine with guard bits:
121 export_bits(val, std::back_inserter(bv), std::numeric_limits<boost::uintmax_t>::digits - 3);
122 import_bits(newval, bv.begin(), bv.end(), std::numeric_limits<boost::uintmax_t>::digits - 3);
123 BOOST_CHECK_EQUAL(val, newval);
126 export_bits(val, std::back_inserter(bv), std::numeric_limits<boost::uintmax_t>::digits - 3, false);
127 import_bits(newval, bv.begin(), bv.end(), std::numeric_limits<boost::uintmax_t>::digits - 3, false);
128 BOOST_CHECK_EQUAL(val, newval);
131 export_bits(val, std::back_inserter(cv), 6);
132 import_bits(newval, cv.begin(), cv.end(), 6);
133 BOOST_CHECK_EQUAL(val, newval);
136 export_bits(val, std::back_inserter(cv), 6, false);
137 import_bits(newval, cv.begin(), cv.end(), 6, false);
138 BOOST_CHECK_EQUAL(val, newval);
140 test_round_trip_neg(val, boost::mpl::bool_<std::numeric_limits<T>::is_signed>());
144 void test_round_trip()
146 std::cout << std::hex;
147 std::cerr << std::hex;
148 for (unsigned i = 0; i < 1000; ++i)
150 T val = generate_random<T>();
151 test_round_trip(val);
155 // See https://github.com/boostorg/multiprecision/issues/21
157 bug << std::numeric_limits<T>::digits - 1;
159 test_round_trip(bug);
164 test_round_trip<boost::multiprecision::cpp_int>();
165 test_round_trip<boost::multiprecision::checked_int1024_t>();
166 test_round_trip<boost::multiprecision::checked_uint512_t>();
167 test_round_trip<boost::multiprecision::number<boost::multiprecision::cpp_int_backend<64, 64, boost::multiprecision::unsigned_magnitude, boost::multiprecision::checked, void> > >();
168 test_round_trip<boost::multiprecision::number<boost::multiprecision::cpp_int_backend<23, 23, boost::multiprecision::unsigned_magnitude, boost::multiprecision::checked, void> > >();
169 return boost::report_errors();