Files
multiprecision/test/test_mixed_cpp_int.cpp
John Maddock 788449ffa5 Add non-member functions for mixed precision arithmetic + tests for same.
Fix a couple of bugs discovered along the way.

[SVN r81151]
2012-11-02 19:13:50 +00:00

86 lines
2.7 KiB
C++

///////////////////////////////////////////////////////////////
// Copyright 2012 John Maddock. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_
//
// Compare arithmetic results using fixed_int to GMP results.
//
#ifdef _MSC_VER
# define _SCL_SECURE_NO_WARNINGS
#endif
#include <boost/multiprecision/cpp_int.hpp>
#include "test.hpp"
template <class Number, class BigNumber>
void test()
{
using namespace boost::multiprecision;
typedef Number test_type;
test_type h = (std::numeric_limits<test_type>::max)();
test_type l = (std::numeric_limits<test_type>::max)();
BigNumber r;
add(r, h, h);
BOOST_CHECK_EQUAL(r, cpp_int(h) + cpp_int(h));
multiply(r, h, h);
BOOST_CHECK_EQUAL(r, cpp_int(h) * cpp_int(h));
if(std::numeric_limits<test_type>::is_signed)
{
subtract(r, l, h);
BOOST_CHECK_EQUAL(r, cpp_int(l) - cpp_int(h));
subtract(r, h, l);
BOOST_CHECK_EQUAL(r, cpp_int(h) - cpp_int(l));
multiply(r, l, l);
BOOST_CHECK_EQUAL(r, cpp_int(l) * cpp_int(l));
}
//
// Try again with integer types as the source:
//
static const unsigned max_digits = std::numeric_limits<test_type>::is_signed ? std::numeric_limits<long long>::digits : std::numeric_limits<unsigned long long>::digits;
static const unsigned require_digits = std::numeric_limits<test_type>::digits <= 2 * max_digits ? std::numeric_limits<test_type>::digits / 2 : max_digits;
typedef typename boost::mpl::if_c<std::numeric_limits<test_type>::is_signed, typename boost::int_t<require_digits>::least, typename boost::uint_t<require_digits>::least>::type i_type;
i_type ih = (std::numeric_limits<i_type>::max)();
i_type il = (std::numeric_limits<i_type>::max)();
add(r, ih, ih);
BOOST_CHECK_EQUAL(r, cpp_int(ih) + cpp_int(ih));
multiply(r, ih, ih);
BOOST_CHECK_EQUAL(r, cpp_int(ih) * cpp_int(ih));
if(std::numeric_limits<test_type>::is_signed)
{
subtract(r, il, ih);
BOOST_CHECK_EQUAL(r, cpp_int(il) - cpp_int(ih));
subtract(r, ih, il);
BOOST_CHECK_EQUAL(r, cpp_int(ih) - cpp_int(il));
multiply(r, il, il);
BOOST_CHECK_EQUAL(r, cpp_int(il) * cpp_int(il));
}
}
int main()
{
using namespace boost::multiprecision;
test<checked_int512_t, checked_int1024_t>();
test<checked_int256_t, checked_int512_t>();
test<number<cpp_int_backend<64, 64, signed_magnitude, checked, void>, et_off>, checked_int512_t>();
test<checked_uint512_t, checked_uint1024_t>();
test<checked_uint256_t, checked_uint512_t>();
test<number<cpp_int_backend<64, 64, unsigned_magnitude, checked, void>, et_off>, checked_uint512_t>();
return boost::report_errors();
}