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#include "app.hpp"
#include "compat/hash.hpp"
#include "compat/array-size.hpp"
#include "src/global-coords.hpp"
#include "src/world.hpp"
#include <cr/StringView.h>
#include <bitset>
#include <memory>
#include <mg/Functions.h>
#ifdef __GNUG__
#pragma GCC diagnostic ignored "-Wunused-macros"
#endif
//#define FM_TEST_DEBUG_PRINT
//#define FM_TEST_DEBUG_VERBOSE
namespace floormat {
namespace {
bool first = true;
void test_simple()
{
constexpr StringView list[] = {
"foo"_s, "bar"_s, "bar\0"_s, "bar2"_s, "baz"_s,
"The quick brown fox jumps over the lazy dog"_s,
"The quick brown fox jumps over the lazy cog"_s,
};
constexpr auto size = array_size(list);
size_t hashes[size] = {};
for (auto i = 0uz; i < size; i++)
hashes[i] = hash_buf(list[i].data(), list[i].size());
for (auto i = 0uz; i < size; i++)
for (auto j = i+1; j < size; j++)
{
if (hashes[i] == hashes[j])
fm_abort("hash collision between '%s' and '%s': 0x%p",
list[i].data(), list[j].data(), (void*)hashes[i]);
}
}
template<int16_t CoordMax, int8_t ZMax, uint32_t MaxCollisions>
[[nodiscard]] bool test_collisions(const char* name)
{
constexpr size_t Iters = (CoordMax*2 + 1)*(CoordMax*2 + 1)*(1+ZMax); // NOLINT(*-implicit-widening-of-multiplication-result)
constexpr size_t BucketCount = Math::max(world::initial_capacity, size_t(Math::ceil(Iters / 0.2f)));
uint32_t num_collisions = 0, iters = 0;
auto bitset_ = std::make_unique<std::bitset<BucketCount>>(false);
auto& bitset = *bitset_;
for (int16_t j = -CoordMax; j <= CoordMax; j++)
for (int16_t i = -CoordMax; i <= CoordMax; i++)
for (int8_t k = 0; k <= ZMax; k++)
{
auto p = global_coords{i, j, k};
auto h = p.hash();
h %= BucketCount;
auto ref = bitset[h];
if (ref) [[unlikely]]
++num_collisions;
else
ref = true;
(void)ref;
iters++;
}
fm_assert_equal(Iters, iters);
constexpr auto print = [](Debug::Color c, StringView status, StringView name, StringView op,
uint32_t num_collisions, uint32_t iters)
{
if (first)
{
DBG_nospace << "";
}
first = false;
DBG_nospace << Debug::color(c) << status << Debug::resetColor
<< ": " << name << "\t"
<< num_collisions << "\t" << op << "\t" << MaxCollisions
<< "\t\t(iters:" << iters << " buckets:" << BucketCount << ")";
};
#define FM_FAIL fm_abort("test/hash: too many collisions")
#ifdef FM_TEST_DEBUG_PRINT
#define FM_MAYBE_FAIL void()
#else
#define FM_MAYBE_FAIL FM_MAYBE_FAIL_
#endif
#define FM_MAYBE_FAIL_ do { if (!success) { DBG_nospace << ""; FM_FAIL; } } while (false)
if (num_collisions > MaxCollisions)
{
print(Debug::Color::Magenta, "fail", name, "!", num_collisions, iters);
#ifdef FM_TEST_DEBUG_PRINT
return false;
#else
FM_FAIL;
#endif
}
else if (num_collisions < MaxCollisions)
{
#if defined FM_TEST_DEBUG_PRINT && defined FM_TEST_DEBUG_VERBOSE
print(Debug::Color::Cyan, "pass", name, " ", num_collisions, iters);
#endif
}
return true;
}
#if !defined FM_TEST_DEBUG_PRINT && defined FM_TEST_DEBUG_VERBOSE
#error assertion failed: !defined FM_TEST_DEBUG_PRINT && defined FM_TEST_DEBUG_VERBOSE
#endif
} // namespace
void Test::test_hash()
{
test_simple();
bool success = true;
first = true;
// best result is xxHash:
success &= test_collisions< 2, 1, 1 >("small1 "); FM_MAYBE_FAIL;
success &= test_collisions< 3, 0, 2 >("small2 "); FM_MAYBE_FAIL;
success &= test_collisions< 4, 0, 2 >("small3 "); FM_MAYBE_FAIL;
success &= test_collisions< 5, 0, 1 >("small4 "); FM_MAYBE_FAIL;
success &= test_collisions< 6, 0, 4 >("mid1 "); FM_MAYBE_FAIL;
success &= test_collisions< 7, 0, 7 >("mid2 "); FM_MAYBE_FAIL;
success &= test_collisions< 8, 0, 10 >("mid3 "); FM_MAYBE_FAIL;
success &= test_collisions< 9, 0, 15 >("mid4 "); FM_MAYBE_FAIL;
success &= test_collisions< 10, 0, 22 >("large1 "); FM_MAYBE_FAIL;
success &= test_collisions< 12, 0, 51 >("large2 "); FM_MAYBE_FAIL;
success &= test_collisions< 14, 0, 94 >("large3 "); FM_MAYBE_FAIL;
success &= test_collisions< 15, 0, 118 >("large4 "); FM_MAYBE_FAIL;
success &= test_collisions< 16, 0, 110 >("large5 "); FM_MAYBE_FAIL;
success &= test_collisions< 3, 1, 2 >("zsmall1"); FM_MAYBE_FAIL;
success &= test_collisions< 4, 1, 3 >("zsmall2"); FM_MAYBE_FAIL;
success &= test_collisions< 2, 3, 1 >("zmid1" ); FM_MAYBE_FAIL;
success &= test_collisions< 3, 3, 7 >("zmid1" ); FM_MAYBE_FAIL;
success &= test_collisions< 2, 6, 4 >("zmid2" ); FM_MAYBE_FAIL;
success &= test_collisions< 2, 10, 14 >("zmid3" ); FM_MAYBE_FAIL;
success &= test_collisions< 6, 2, 35 >("zmid4" ); FM_MAYBE_FAIL;
success &= test_collisions< 7, 1, 28 >("zmid5" ); FM_MAYBE_FAIL;
success &= test_collisions< 10, 1, 89 >("zlarge1"); FM_MAYBE_FAIL;
success &= test_collisions< 10, 4, 274 >("zlarge2"); FM_MAYBE_FAIL;
success &= test_collisions< 16, 8, 1126 >("zlarge3"); FM_MAYBE_FAIL;
success &= test_collisions< 32, 8, 4397 >("zlarge4"); FM_MAYBE_FAIL;
(void)success;
FM_MAYBE_FAIL_;
}
} // namespace floormat
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