diff options
Diffstat (limited to 'absl')
| -rw-r--r-- | absl/hash/internal/hash.h | 52 | ||||
| -rw-r--r-- | absl/hash/internal/low_level_hash_test.cc | 50 |
2 files changed, 96 insertions, 6 deletions
diff --git a/absl/hash/internal/hash.h b/absl/hash/internal/hash.h index e5af0ac0..b1e33caf 100644 --- a/absl/hash/internal/hash.h +++ b/absl/hash/internal/hash.h @@ -21,6 +21,7 @@ #include <algorithm> #include <array> +#include <bitset> #include <cmath> #include <cstring> #include <deque> @@ -489,8 +490,9 @@ typename std::enable_if<is_hashable<T>::value, H>::type AbslHashValue( // AbslHashValue for hashing std::vector // -// Do not use this for vector<bool>. It does not have a .data(), and a fallback -// for std::hash<> is most likely faster. +// Do not use this for vector<bool> on platforms that have a working +// implementation of std::hash. It does not have a .data(), and a fallback for +// std::hash<> is most likely faster. template <typename H, typename T, typename Allocator> typename std::enable_if<is_hashable<T>::value && !std::is_same<T, bool>::value, H>::type @@ -500,6 +502,27 @@ AbslHashValue(H hash_state, const std::vector<T, Allocator>& vector) { vector.size()); } +#if defined(ABSL_IS_BIG_ENDIAN) && \ + (defined(__GLIBCXX__) || defined(__GLIBCPP__)) +// AbslHashValue for hashing std::vector<bool> +// +// std::hash in libstdc++ does not work correctly with vector<bool> on Big +// Endian platforms therefore we need to implement a custom AbslHashValue for +// it. More details on the bug: +// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102531 +template <typename H, typename T, typename Allocator> +typename std::enable_if<is_hashable<T>::value && std::is_same<T, bool>::value, + H>::type +AbslHashValue(H hash_state, const std::vector<T, Allocator>& vector) { + typename H::AbslInternalPiecewiseCombiner combiner; + for (const auto& i : vector) { + unsigned char c = static_cast<unsigned char>(i); + hash_state = combiner.add_buffer(std::move(hash_state), &c, sizeof(c)); + } + return H::combine(combiner.finalize(std::move(hash_state)), vector.size()); +} +#endif + // ----------------------------------------------------------------------------- // AbslHashValue for Ordered Associative Containers // ----------------------------------------------------------------------------- @@ -592,9 +615,28 @@ AbslHashValue(H hash_state, const absl::variant<T...>& v) { // AbslHashValue for Other Types // ----------------------------------------------------------------------------- -// AbslHashValue for hashing std::bitset is not defined, for the same reason as -// for vector<bool> (see std::vector above): It does not expose the raw bytes, -// and a fallback to std::hash<> is most likely faster. +// AbslHashValue for hashing std::bitset is not defined on Little Endian +// platforms, for the same reason as for vector<bool> (see std::vector above): +// It does not expose the raw bytes, and a fallback to std::hash<> is most +// likely faster. + +#if defined(ABSL_IS_BIG_ENDIAN) && \ + (defined(__GLIBCXX__) || defined(__GLIBCPP__)) +// AbslHashValue for hashing std::bitset +// +// std::hash in libstdc++ does not work correctly with std::bitset on Big Endian +// platforms therefore we need to implement a custom AbslHashValue for it. More +// details on the bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102531 +template <typename H, size_t N> +H AbslHashValue(H hash_state, const std::bitset<N>& set) { + typename H::AbslInternalPiecewiseCombiner combiner; + for (int i = 0; i < N; i++) { + unsigned char c = static_cast<unsigned char>(set[i]); + hash_state = combiner.add_buffer(std::move(hash_state), &c, sizeof(c)); + } + return H::combine(combiner.finalize(std::move(hash_state)), N); +} +#endif // ----------------------------------------------------------------------------- diff --git a/absl/hash/internal/low_level_hash_test.cc b/absl/hash/internal/low_level_hash_test.cc index cf22dc3c..ae930b34 100644 --- a/absl/hash/internal/low_level_hash_test.cc +++ b/absl/hash/internal/low_level_hash_test.cc @@ -404,7 +404,55 @@ TEST(LowLevelHashTest, VerifyGolden) { uint64_t{0xc9ae5c8759b4877a}}, }; -#if defined(__aarch64__) +#if defined(ABSL_IS_BIG_ENDIAN) + constexpr uint64_t kGolden[kNumGoldenOutputs] = { + 0xe5a40d39ab796423, 0x1766974bf7527d81, 0x5c3bbbe230db17a8, + 0xa6630143a7e6aa6f, 0x17645cb7318b86b, 0x218b175f30ba61f8, + 0xa6564b468248c683, 0xef192f401b116e1c, 0xbe8dc0c54617639d, + 0xe7b01610fc22dbb8, 0x99d9f694404af913, 0xf4eecd37464b45c5, + 0x7d2c653d63596d9b, 0x3f15c8544ec5393a, 0x6b9dc0c1704f796c, + 0xf1ded7a7eae5ed5a, 0x2db2fd7c6dd4641b, 0x151ca2d3d4cd33ab, + 0xa5af5994ac2ccd64, 0x2b2a4ca3191d2fce, 0xf89e68c9364e7c05, + 0x71724c70b799c21, 0x70536fabfd157369, 0xdee92794c3c3082b, + 0xac033a6743d3b3eb, 0xed2956b506cd5151, 0xbd669644755264b6, + 0x6ab1ff5d5f549a63, 0xf6bd551a2e3e04e, 0x7b5a8cef6875ea73, + 0x22bccf4d4db0a91c, 0x4f2bc07754c7c7eb, 0xfb6b8342a86725db, + 0x13a1a0d4c5854da, 0x5f6e44655f7dedac, 0x54a9198dff2bdf85, + 0xdb17e6915d4e4042, 0xa69926cf5c3b89f, 0xf77f031bfd74c096, + 0x1d6f916fdd50ec3c, 0x334ac76013ade393, 0x99370f899111de15, + 0x352457a03ada6de, 0x341974d4f42d854d, 0xda89ab02872aeb5, + 0x6ec2b74e143b10d9, 0x6f284c0b5cd60522, 0xf9670de353438f88, + 0xde920913adf0a2b4, 0xb7a07d7c0c17a8ec, 0x879a69f558ba3a98, + 0x360cf6d802df20f9, 0x53530f8046673738, 0xbd8f5f2bcf35e483, + 0x3f171f047144b983, 0x644d04e820823465, 0x50e44773a20b2702, + 0xe584ed4c05c745dd, 0x9a825c85b95ab6c0, 0xbce2931deb74e775, + 0x10468e9e705c7cfe, 0x12e01de3104141e2, 0x5c11ae2ee3713abd, + 0x6ac5ffb0860319e6, 0xc1e6da1849d30fc9, 0xa0e4d247a458b447, + 0x4530d4615c32b89b, 0x116aa09107a76505, 0xf941339d00d9bb73, + 0x573a0fc1615afb33, 0xa975c81dc868b258, 0x3ab2c5250ab54bda, + 0x37f99f208a3e3b11, 0x4b49b0ff706689d, 0x30bafa0b8f0a87fe, + 0xea6787a65cc20cdd, 0x55861729f1fc3ab8, 0xea38e009c5be9b72, + 0xcb8522cba33c3c66, 0x352e77653fe306f3, 0xe0bb760793bac064, + 0xf66ec59322662956, 0x637aa320455d56f8, 0x46ee546be5824a89, + 0x9e6842421e83d8a4, 0xf98ac2bc96b9fb8c, 0xf2c1002fd9a70b99, + 0x4c2b62b1e39e9405, 0x3248555fa3ade9c4, 0xd4d04c37f6417c21, + 0xf40cd506b1bf5653, 0x6c45d6005c760d2f, 0x61d88a7e61ff0d7e, + 0x131591e8a53cc967, 0xdae85cb9bc29bab6, 0xe98835334905e626, + 0x7cce50a2b66b8754, 0x5b0b3d0c5ac498ae, 0xd35a218c974d1756, + 0xfce436ddc1d003c, 0xd183901de90bb741, 0x9378f8f34974a66, + 0x21f11ae0a0402368, 0xf2fbd7c94ef89cb6, 0xc329c69d0f0d080b, + 0xf2841cba16216a61, 0x47aba97b44916df1, 0x724d4e00a8019fcf, + 0x2df9005c2a728d63, 0xc788892a1a5d7515, 0x9e993a65f9df0480, + 0x76876721ff49f969, 0xbe7a796cfba15bf5, 0xa4c8bd54586f5488, + 0xb390a325275501ab, 0x893f11317427ccf1, 0x92f2bb57da5695b9, + 0x30985b90da88269f, 0x2c690e268e086de8, 0x1c02df6097997196, + 0x1f9778f8bbdf6455, 0x7d57378c7bf8416d, 0xba8582a5f8d84d38, + 0xe8ca43b85050be4e, 0x5048cf6bed8a5d9f, 0xfbc5ba80917d0ea4, + 0x8011026525bf1691, 0x26b8dc6aed9fb50d, 0x191f5bfee77c1fe3, + 0xdd497891465a2cc1, 0x6f1fe8c57a33072e, 0x2c9f4ec078c460c0, + 0x9a725bde8f6a1437, 0x6ce545fa3ef61e4d, + }; +#elif defined(__aarch64__) constexpr uint64_t kGolden[kNumGoldenOutputs] = { 0x45c0aadee165dcbe, 0x25ed8587f6f20d06, 0x5f23ae668ce7926d, 0xfef74d1da0846719, 0x54478408e68cb7d4, 0xee27ddaf88c6fe68, |