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made fast_modulo universally available in 64 bits and never used in 32 bits

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This commit is contained in:
joaquintides
2022-06-26 19:13:54 +02:00
parent 2670bb149d
commit fb733483c6
2 changed files with 26 additions and 78 deletions
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test/unordered/prime_fmod_tests.cpp
+11 -48
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@@ -28,15 +28,6 @@ void macros_test()
"BOOST_UNORDERED_FCA_HAS_64B_SIZE_T is defined");
#endif
}
#if ((defined(__GNUC__) || defined(__clang__)) && \
defined(__SIZEOF_INT128__)) || \
(defined(_MSC_VER) && defined(_M_X64))
#if !defined(BOOST_UNORDERED_FCA_FASTMOD_SUPPORT)
BOOST_ERROR("fast_modulo support should be enabled for this toolchain but "
"it's currently not");
#endif
#endif
}
// Pretty inefficient, but the test is fast enough.
@@ -93,7 +84,7 @@ void prime_sizes_test()
BOOST_TEST_GT(sizes[i], sizes[i - 1]);
}
#if defined(BOOST_UNORDERED_FCA_FASTMOD_SUPPORT)
#if defined(BOOST_UNORDERED_FCA_HAS_64B_SIZE_T)
// now we wish to prove that if we do have the reciprocals stored, we have the
// correct amount of them, i.e. one for every entry in sizes[] that fits in 32
// bits
@@ -140,13 +131,14 @@ void prime_sizes_test()
void get_remainder_test()
{
#if defined(BOOST_UNORDERED_FCA_FASTMOD_SUPPORT)
#if defined(BOOST_UNORDERED_FCA_HAS_64B_SIZE_T)
struct
{
// internally, our get_remainder() function will rely on either msvc
// intrinsics or 128 bit integer support which isn't always available. This
// is a slower, portable version we can use for verification of the
// routines.
// boost::unordered::detail::prime_fmod_size<>::get_remainder
// uses several internal implementations depending on the availability of
// certain intrinsics or 128 bit integer support, defaulting to a slow,
// portable routine. The following is a transcription of the portable
// routine used here for verification purposes.
//
boost::uint64_t operator()(boost::uint64_t f, boost::uint32_t d)
{
@@ -178,7 +170,7 @@ void get_remainder_test()
#endif
}
void modulo32_test()
void modulo_test()
{
std::size_t* sizes = boost::unordered::detail::prime_fmod_size<>::sizes;
@@ -188,39 +180,12 @@ void modulo32_test()
boost::detail::splitmix64 rng;
for (std::size_t i = 0; i < 1000000u; ++i) {
std::size_t hash = static_cast<boost::uint32_t>(rng());
for (std::size_t j = 0; j < sizes_len; ++j) {
std::size_t p1 =
boost::unordered::detail::prime_fmod_size<>::position(hash, j);
std::size_t p2 = hash % sizes[j];
if (!BOOST_TEST_EQ(p1, p2)) {
std::cerr << "hash: " << hash << ", j: " << j << ", sizes[" << j
<< "]: " << sizes[j] << std::endl;
return;
}
}
}
}
void modulo64_test()
{
#if defined(BOOST_UNORDERED_FCA_HAS_64B_SIZE_T)
std::size_t* sizes = boost::unordered::detail::prime_fmod_size<>::sizes;
std::size_t const sizes_len =
boost::unordered::detail::prime_fmod_size<>::sizes_len;
boost::detail::splitmix64 rng;
for (std::size_t i = 0; i < 1000000u; ++i) {
std::size_t hash = rng();
std::size_t hash = static_cast<std::size_t>(rng());
for (std::size_t j = 0; j < sizes_len; ++j) {
std::size_t h = hash;
#if defined(BOOST_UNORDERED_FCA_FASTMOD_SUPPORT)
#if defined(BOOST_UNORDERED_FCA_HAS_64B_SIZE_T)
if (sizes[j] <= UINT_MAX) {
h = boost::uint32_t(h) + boost::uint32_t(h >> 32);
}
@@ -237,16 +202,14 @@ void modulo64_test()
}
}
}
#endif
}
int main()
{
macros_test();
prime_sizes_test();
modulo32_test();
get_remainder_test();
modulo64_test();
modulo_test();
return boost::report_errors();
}