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Fix initialization of tabulation hash #7144

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Fix initialization of tabulation hash #7144

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3809ae4
Fix initialization of tabulation hash
DennisOSRM Apr 3, 2025
adebca7
Merge branch 'master' into tabhash_init
DennisOSRM Apr 3, 2025
acb29ca
Merge branch 'master' into tabhash_init
DennisOSRM Apr 17, 2025
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10 changes: 4 additions & 6 deletions include/util/xor_fast_hash.hpp
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Original file line number Diff line number Diff line change
Expand Up @@ -42,13 +42,11 @@ template <std::size_t MaxNumElements = (1u << 16u)> class XORFastHash
public:
XORFastHash()
{
std::mt19937 generator(1); // impl. defined but deterministic default seed
std::mt19937 generator(0xdeadbeef);
std::uniform_int_distribution<> distrib(0, UINT16_MAX);

std::iota(begin(table1), end(table1), 0u);
std::shuffle(begin(table1), end(table1), generator);

std::iota(begin(table2), end(table2), 0u);
std::shuffle(begin(table2), end(table2), generator);
std::fill(begin(table1), end(table1), distrib(generator));
std::fill(begin(table2), end(table2), distrib(generator));
}

inline std::uint16_t operator()(const std::uint32_t originalValue) const
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