ceph/src/boost/libs/core/test/bit_popcount_test.cpp

   1 // Test for boost/core/bit.hpp (bit_ceil)
   2 //
   3 // Copyright 2020 Peter Dimov
   4 // Distributed under the Boost Software License, Version 1.0.
   5 // https://www.boost.org/LICENSE_1_0.txt
   6
   7 #include <boost/core/bit.hpp>
   8 #include <boost/core/lightweight_test.hpp>
   9 #include <boost/core/detail/splitmix64.hpp>
  10 #include <boost/cstdint.hpp>
  11 #include <limits>
  12 #include <iostream>
  13
  14 template<class T> void test_popcount( T x )
  15 {
  16     int k = 0;
  17     for( T y = x; y; y &= y - 1, ++k );
  18
  19     BOOST_TEST_EQ( boost::core::popcount( x ), k ) || ( std::cerr << "x: " << +x << std::endl );
  20 }
  21
  22 int main()
  23 {
  24     {
  25         test_popcount( static_cast<unsigned char>( 0 ) );
  26         test_popcount( static_cast<unsigned short>( 0 ) );
  27         test_popcount( static_cast<unsigned int>( 0 ) );
  28         test_popcount( static_cast<unsigned long>( 0 ) );
  29         test_popcount( static_cast<boost::ulong_long_type>( 0 ) );
  30     }
  31
  32     boost::detail::splitmix64 rng;
  33
  34     for( int i = 0; i < 1000; ++i )
  35     {
  36         boost::uint64_t x = rng();
  37
  38         test_popcount( static_cast<unsigned char>( x ) );
  39         test_popcount( static_cast<unsigned short>( x ) );
  40         test_popcount( static_cast<unsigned int>( x ) );
  41         test_popcount( static_cast<unsigned long>( x ) );
  42         test_popcount( static_cast<boost::ulong_long_type>( x ) );
  43     }
  44
  45     return boost::report_errors();
  46 }