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-rw-r--r--src/rocksdb/util/hash_test.cc853
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diff --git a/src/rocksdb/util/hash_test.cc b/src/rocksdb/util/hash_test.cc
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+++ b/src/rocksdb/util/hash_test.cc
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+// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
+// This source code is licensed under both the GPLv2 (found in the
+// COPYING file in the root directory) and Apache 2.0 License
+// (found in the LICENSE.Apache file in the root directory).
+//
+// Copyright (c) 2012 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/hash.h"
+
+#include <cstring>
+#include <type_traits>
+#include <vector>
+
+#include "test_util/testharness.h"
+#include "util/coding.h"
+#include "util/coding_lean.h"
+#include "util/hash128.h"
+#include "util/math.h"
+#include "util/math128.h"
+
+using ROCKSDB_NAMESPACE::BijectiveHash2x64;
+using ROCKSDB_NAMESPACE::BijectiveUnhash2x64;
+using ROCKSDB_NAMESPACE::DecodeFixed64;
+using ROCKSDB_NAMESPACE::EncodeFixed32;
+using ROCKSDB_NAMESPACE::EndianSwapValue;
+using ROCKSDB_NAMESPACE::GetSliceHash64;
+using ROCKSDB_NAMESPACE::Hash;
+using ROCKSDB_NAMESPACE::Hash128;
+using ROCKSDB_NAMESPACE::Hash2x64;
+using ROCKSDB_NAMESPACE::Hash64;
+using ROCKSDB_NAMESPACE::Lower32of64;
+using ROCKSDB_NAMESPACE::Lower64of128;
+using ROCKSDB_NAMESPACE::ReverseBits;
+using ROCKSDB_NAMESPACE::Slice;
+using ROCKSDB_NAMESPACE::Unsigned128;
+using ROCKSDB_NAMESPACE::Upper32of64;
+using ROCKSDB_NAMESPACE::Upper64of128;
+
+// The hash algorithm is part of the file format, for example for the Bloom
+// filters. Test that the hash values are stable for a set of random strings of
+// varying lengths.
+TEST(HashTest, Values) {
+ constexpr uint32_t kSeed = 0xbc9f1d34; // Same as BloomHash.
+
+ EXPECT_EQ(Hash("", 0, kSeed), 3164544308u);
+ EXPECT_EQ(Hash("\x08", 1, kSeed), 422599524u);
+ EXPECT_EQ(Hash("\x17", 1, kSeed), 3168152998u);
+ EXPECT_EQ(Hash("\x9a", 1, kSeed), 3195034349u);
+ EXPECT_EQ(Hash("\x1c", 1, kSeed), 2651681383u);
+ EXPECT_EQ(Hash("\x4d\x76", 2, kSeed), 2447836956u);
+ EXPECT_EQ(Hash("\x52\xd5", 2, kSeed), 3854228105u);
+ EXPECT_EQ(Hash("\x91\xf7", 2, kSeed), 31066776u);
+ EXPECT_EQ(Hash("\xd6\x27", 2, kSeed), 1806091603u);
+ EXPECT_EQ(Hash("\x30\x46\x0b", 3, kSeed), 3808221797u);
+ EXPECT_EQ(Hash("\x56\xdc\xd6", 3, kSeed), 2157698265u);
+ EXPECT_EQ(Hash("\xd4\x52\x33", 3, kSeed), 1721992661u);
+ EXPECT_EQ(Hash("\x6a\xb5\xf4", 3, kSeed), 2469105222u);
+ EXPECT_EQ(Hash("\x67\x53\x81\x1c", 4, kSeed), 118283265u);
+ EXPECT_EQ(Hash("\x69\xb8\xc0\x88", 4, kSeed), 3416318611u);
+ EXPECT_EQ(Hash("\x1e\x84\xaf\x2d", 4, kSeed), 3315003572u);
+ EXPECT_EQ(Hash("\x46\xdc\x54\xbe", 4, kSeed), 447346355u);
+ EXPECT_EQ(Hash("\xd0\x7a\x6e\xea\x56", 5, kSeed), 4255445370u);
+ EXPECT_EQ(Hash("\x86\x83\xd5\xa4\xd8", 5, kSeed), 2390603402u);
+ EXPECT_EQ(Hash("\xb7\x46\xbb\x77\xce", 5, kSeed), 2048907743u);
+ EXPECT_EQ(Hash("\x6c\xa8\xbc\xe5\x99", 5, kSeed), 2177978500u);
+ EXPECT_EQ(Hash("\x5c\x5e\xe1\xa0\x73\x81", 6, kSeed), 1036846008u);
+ EXPECT_EQ(Hash("\x08\x5d\x73\x1c\xe5\x2e", 6, kSeed), 229980482u);
+ EXPECT_EQ(Hash("\x42\xfb\xf2\x52\xb4\x10", 6, kSeed), 3655585422u);
+ EXPECT_EQ(Hash("\x73\xe1\xff\x56\x9c\xce", 6, kSeed), 3502708029u);
+ EXPECT_EQ(Hash("\x5c\xbe\x97\x75\x54\x9a\x52", 7, kSeed), 815120748u);
+ EXPECT_EQ(Hash("\x16\x82\x39\x49\x88\x2b\x36", 7, kSeed), 3056033698u);
+ EXPECT_EQ(Hash("\x59\x77\xf0\xa7\x24\xf4\x78", 7, kSeed), 587205227u);
+ EXPECT_EQ(Hash("\xd3\xa5\x7c\x0e\xc0\x02\x07", 7, kSeed), 2030937252u);
+ EXPECT_EQ(Hash("\x31\x1b\x98\x75\x96\x22\xd3\x9a", 8, kSeed), 469635402u);
+ EXPECT_EQ(Hash("\x38\xd6\xf7\x28\x20\xb4\x8a\xe9", 8, kSeed), 3530274698u);
+ EXPECT_EQ(Hash("\xbb\x18\x5d\xf4\x12\x03\xf7\x99", 8, kSeed), 1974545809u);
+ EXPECT_EQ(Hash("\x80\xd4\x3b\x3b\xae\x22\xa2\x78", 8, kSeed), 3563570120u);
+ EXPECT_EQ(Hash("\x1a\xb5\xd0\xfe\xab\xc3\x61\xb2\x99", 9, kSeed),
+ 2706087434u);
+ EXPECT_EQ(Hash("\x8e\x4a\xc3\x18\x20\x2f\x06\xe6\x3c", 9, kSeed),
+ 1534654151u);
+ EXPECT_EQ(Hash("\xb6\xc0\xdd\x05\x3f\xc4\x86\x4c\xef", 9, kSeed),
+ 2355554696u);
+ EXPECT_EQ(Hash("\x9a\x5f\x78\x0d\xaf\x50\xe1\x1f\x55", 9, kSeed),
+ 1400800912u);
+ EXPECT_EQ(Hash("\x22\x6f\x39\x1f\xf8\xdd\x4f\x52\x17\x94", 10, kSeed),
+ 3420325137u);
+ EXPECT_EQ(Hash("\x32\x89\x2a\x75\x48\x3a\x4a\x02\x69\xdd", 10, kSeed),
+ 3427803584u);
+ EXPECT_EQ(Hash("\x06\x92\x5c\xf4\x88\x0e\x7e\x68\x38\x3e", 10, kSeed),
+ 1152407945u);
+ EXPECT_EQ(Hash("\xbd\x2c\x63\x38\xbf\xe9\x78\xb7\xbf\x15", 10, kSeed),
+ 3382479516u);
+}
+
+// The hash algorithm is part of the file format, for example for the Bloom
+// filters.
+TEST(HashTest, Hash64Misc) {
+ constexpr uint32_t kSeed = 0; // Same as GetSliceHash64
+
+ for (char fill : {'\0', 'a', '1', '\xff'}) {
+ const size_t max_size = 1000;
+ const std::string str(max_size, fill);
+
+ for (size_t size = 0; size <= max_size; ++size) {
+ uint64_t here = Hash64(str.data(), size, kSeed);
+
+ // Must be same as unseeded Hash64 and GetSliceHash64
+ EXPECT_EQ(here, Hash64(str.data(), size));
+ EXPECT_EQ(here, GetSliceHash64(Slice(str.data(), size)));
+
+ // Upper and Lower must reconstruct hash
+ EXPECT_EQ(here, (uint64_t{Upper32of64(here)} << 32) | Lower32of64(here));
+ EXPECT_EQ(here, (uint64_t{Upper32of64(here)} << 32) + Lower32of64(here));
+ EXPECT_EQ(here, (uint64_t{Upper32of64(here)} << 32) ^ Lower32of64(here));
+
+ // Seed changes hash value (with high probability)
+ for (uint64_t var_seed = 1; var_seed != 0; var_seed <<= 1) {
+ EXPECT_NE(here, Hash64(str.data(), size, var_seed));
+ }
+
+ // Size changes hash value (with high probability)
+ size_t max_smaller_by = std::min(size_t{30}, size);
+ for (size_t smaller_by = 1; smaller_by <= max_smaller_by; ++smaller_by) {
+ EXPECT_NE(here, Hash64(str.data(), size - smaller_by, kSeed));
+ }
+ }
+ }
+}
+
+// Test that hash values are "non-trivial" for "trivial" inputs
+TEST(HashTest, Hash64Trivial) {
+ // Thorough test too slow for regression testing
+ constexpr bool thorough = false;
+
+ // For various seeds, make sure hash of empty string is not zero.
+ constexpr uint64_t max_seed = thorough ? 0x1000000 : 0x10000;
+ for (uint64_t seed = 0; seed < max_seed; ++seed) {
+ uint64_t here = Hash64("", 0, seed);
+ EXPECT_NE(Lower32of64(here), 0u);
+ EXPECT_NE(Upper32of64(here), 0u);
+ }
+
+ // For standard seed, make sure hash of small strings are not zero
+ constexpr uint32_t kSeed = 0; // Same as GetSliceHash64
+ char input[4];
+ constexpr int max_len = thorough ? 3 : 2;
+ for (int len = 1; len <= max_len; ++len) {
+ for (uint32_t i = 0; (i >> (len * 8)) == 0; ++i) {
+ EncodeFixed32(input, i);
+ uint64_t here = Hash64(input, len, kSeed);
+ EXPECT_NE(Lower32of64(here), 0u);
+ EXPECT_NE(Upper32of64(here), 0u);
+ }
+ }
+}
+
+// Test that the hash values are stable for a set of random strings of
+// varying small lengths.
+TEST(HashTest, Hash64SmallValueSchema) {
+ constexpr uint32_t kSeed = 0; // Same as GetSliceHash64
+
+ EXPECT_EQ(Hash64("", 0, kSeed), uint64_t{5999572062939766020u});
+ EXPECT_EQ(Hash64("\x08", 1, kSeed), uint64_t{583283813901344696u});
+ EXPECT_EQ(Hash64("\x17", 1, kSeed), uint64_t{16175549975585474943u});
+ EXPECT_EQ(Hash64("\x9a", 1, kSeed), uint64_t{16322991629225003903u});
+ EXPECT_EQ(Hash64("\x1c", 1, kSeed), uint64_t{13269285487706833447u});
+ EXPECT_EQ(Hash64("\x4d\x76", 2, kSeed), uint64_t{6859542833406258115u});
+ EXPECT_EQ(Hash64("\x52\xd5", 2, kSeed), uint64_t{4919611532550636959u});
+ EXPECT_EQ(Hash64("\x91\xf7", 2, kSeed), uint64_t{14199427467559720719u});
+ EXPECT_EQ(Hash64("\xd6\x27", 2, kSeed), uint64_t{12292689282614532691u});
+ EXPECT_EQ(Hash64("\x30\x46\x0b", 3, kSeed), uint64_t{11404699285340020889u});
+ EXPECT_EQ(Hash64("\x56\xdc\xd6", 3, kSeed), uint64_t{12404347133785524237u});
+ EXPECT_EQ(Hash64("\xd4\x52\x33", 3, kSeed), uint64_t{15853805298481534034u});
+ EXPECT_EQ(Hash64("\x6a\xb5\xf4", 3, kSeed), uint64_t{16863488758399383382u});
+ EXPECT_EQ(Hash64("\x67\x53\x81\x1c", 4, kSeed),
+ uint64_t{9010661983527562386u});
+ EXPECT_EQ(Hash64("\x69\xb8\xc0\x88", 4, kSeed),
+ uint64_t{6611781377647041447u});
+ EXPECT_EQ(Hash64("\x1e\x84\xaf\x2d", 4, kSeed),
+ uint64_t{15290969111616346501u});
+ EXPECT_EQ(Hash64("\x46\xdc\x54\xbe", 4, kSeed),
+ uint64_t{7063754590279313623u});
+ EXPECT_EQ(Hash64("\xd0\x7a\x6e\xea\x56", 5, kSeed),
+ uint64_t{6384167718754869899u});
+ EXPECT_EQ(Hash64("\x86\x83\xd5\xa4\xd8", 5, kSeed),
+ uint64_t{16874407254108011067u});
+ EXPECT_EQ(Hash64("\xb7\x46\xbb\x77\xce", 5, kSeed),
+ uint64_t{16809880630149135206u});
+ EXPECT_EQ(Hash64("\x6c\xa8\xbc\xe5\x99", 5, kSeed),
+ uint64_t{1249038833153141148u});
+ EXPECT_EQ(Hash64("\x5c\x5e\xe1\xa0\x73\x81", 6, kSeed),
+ uint64_t{17358142495308219330u});
+ EXPECT_EQ(Hash64("\x08\x5d\x73\x1c\xe5\x2e", 6, kSeed),
+ uint64_t{4237646583134806322u});
+ EXPECT_EQ(Hash64("\x42\xfb\xf2\x52\xb4\x10", 6, kSeed),
+ uint64_t{4373664924115234051u});
+ EXPECT_EQ(Hash64("\x73\xe1\xff\x56\x9c\xce", 6, kSeed),
+ uint64_t{12012981210634596029u});
+ EXPECT_EQ(Hash64("\x5c\xbe\x97\x75\x54\x9a\x52", 7, kSeed),
+ uint64_t{5716522398211028826u});
+ EXPECT_EQ(Hash64("\x16\x82\x39\x49\x88\x2b\x36", 7, kSeed),
+ uint64_t{15604531309862565013u});
+ EXPECT_EQ(Hash64("\x59\x77\xf0\xa7\x24\xf4\x78", 7, kSeed),
+ uint64_t{8601330687345614172u});
+ EXPECT_EQ(Hash64("\xd3\xa5\x7c\x0e\xc0\x02\x07", 7, kSeed),
+ uint64_t{8088079329364056942u});
+ EXPECT_EQ(Hash64("\x31\x1b\x98\x75\x96\x22\xd3\x9a", 8, kSeed),
+ uint64_t{9844314944338447628u});
+ EXPECT_EQ(Hash64("\x38\xd6\xf7\x28\x20\xb4\x8a\xe9", 8, kSeed),
+ uint64_t{10973293517982163143u});
+ EXPECT_EQ(Hash64("\xbb\x18\x5d\xf4\x12\x03\xf7\x99", 8, kSeed),
+ uint64_t{9986007080564743219u});
+ EXPECT_EQ(Hash64("\x80\xd4\x3b\x3b\xae\x22\xa2\x78", 8, kSeed),
+ uint64_t{1729303145008254458u});
+ EXPECT_EQ(Hash64("\x1a\xb5\xd0\xfe\xab\xc3\x61\xb2\x99", 9, kSeed),
+ uint64_t{13253403748084181481u});
+ EXPECT_EQ(Hash64("\x8e\x4a\xc3\x18\x20\x2f\x06\xe6\x3c", 9, kSeed),
+ uint64_t{7768754303876232188u});
+ EXPECT_EQ(Hash64("\xb6\xc0\xdd\x05\x3f\xc4\x86\x4c\xef", 9, kSeed),
+ uint64_t{12439346786701492u});
+ EXPECT_EQ(Hash64("\x9a\x5f\x78\x0d\xaf\x50\xe1\x1f\x55", 9, kSeed),
+ uint64_t{10841838338450144690u});
+ EXPECT_EQ(Hash64("\x22\x6f\x39\x1f\xf8\xdd\x4f\x52\x17\x94", 10, kSeed),
+ uint64_t{12883919702069153152u});
+ EXPECT_EQ(Hash64("\x32\x89\x2a\x75\x48\x3a\x4a\x02\x69\xdd", 10, kSeed),
+ uint64_t{12692903507676842188u});
+ EXPECT_EQ(Hash64("\x06\x92\x5c\xf4\x88\x0e\x7e\x68\x38\x3e", 10, kSeed),
+ uint64_t{6540985900674032620u});
+ EXPECT_EQ(Hash64("\xbd\x2c\x63\x38\xbf\xe9\x78\xb7\xbf\x15", 10, kSeed),
+ uint64_t{10551812464348219044u});
+}
+
+std::string Hash64TestDescriptor(const char *repeat, size_t limit) {
+ const char *mod61_encode =
+ "abcdefghijklmnopqrstuvwxyz123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
+ std::string input;
+ while (input.size() < limit) {
+ input.append(repeat);
+ }
+ std::string rv;
+ for (size_t i = 0; i < limit; ++i) {
+ uint64_t h = GetSliceHash64(Slice(input.data(), i));
+ rv.append(1, mod61_encode[static_cast<size_t>(h % 61)]);
+ }
+ return rv;
+}
+
+// XXPH3 changes its algorithm for various sizes up through 250 bytes, so
+// we need to check the stability of larger sizes also.
+TEST(HashTest, Hash64LargeValueSchema) {
+ // Each of these derives a "descriptor" from the hash values for all
+ // lengths up to 430.
+ // Note that "c" is common for the zero-length string.
+ EXPECT_EQ(
+ Hash64TestDescriptor("foo", 430),
+ "cRhyWsY67B6klRA1udmOuiYuX7IthyGBKqbeosz2hzVglWCmQx8nEdnpkvPfYX56Up2OWOTV"
+ "lTzfAoYwvtqKzjD8E9xttR2unelbXbIV67NUe6bOO23BxaSFRcA3njGu5cUWfgwOqNoTsszp"
+ "uPvKRP6qaUR5VdoBkJUCFIefd7edlNK5mv6JYWaGdwxehg65hTkTmjZoPKxTZo4PLyzbL9U4"
+ "xt12ITSfeP2MfBHuLI2z2pDlBb44UQKVMx27LEoAHsdLp3WfWfgH3sdRBRCHm33UxCM4QmE2"
+ "xJ7gqSvNwTeH7v9GlC8zWbGroyD3UVNeShMLx29O7tH1biemLULwAHyIw8zdtLMDpEJ8m2ic"
+ "l6Lb4fDuuFNAs1GCVUthjK8CV8SWI8Rsz5THSwn5CGhpqUwSZcFknjwWIl5rNCvDxXJqYr");
+ // Note that "1EeRk" is common for "Rocks"
+ EXPECT_EQ(
+ Hash64TestDescriptor("Rocks", 430),
+ "c1EeRkrzgOYWLA8PuhJrwTePJewoB44WdXYDfhbk3ZxTqqg25WlPExDl7IKIQLJvnA6gJxxn"
+ "9TCSLkFGfJeXehaSS1GBqWSzfhEH4VXiXIUCuxJXxtKXcSC6FrNIQGTZbYDiUOLD6Y5inzrF"
+ "9etwQhXUBanw55xAUdNMFQAm2GjJ6UDWp2mISLiMMkLjANWMKLaZMqaFLX37qB4MRO1ooVRv"
+ "zSvaNRSCLxlggQCasQq8icWjzf3HjBlZtU6pd4rkaUxSzHqmo9oM5MghbU5Rtxg8wEfO7lVN"
+ "5wdMONYecslQTwjZUpO1K3LDf3K3XK6sUXM6ShQQ3RHmMn2acB4YtTZ3QQcHYJSOHn2DuWpa"
+ "Q8RqzX5lab92YmOLaCdOHq1BPsM7SIBzMdLgePNsJ1vvMALxAaoDUHPxoFLO2wx18IXnyX");
+ EXPECT_EQ(
+ Hash64TestDescriptor("RocksDB", 430),
+ "c1EeRkukbkb28wLTahwD2sfUhZzaBEnF8SVrxnPVB6A7b8CaAl3UKsDZISF92GSq2wDCukOq"
+ "Jgrsp7A3KZhDiLW8dFXp8UPqPxMCRlMdZeVeJ2dJxrmA6cyt99zkQFj7ELbut6jAeVqARFnw"
+ "fnWVXOsaLrq7bDCbMcns2DKvTaaqTCLMYxI7nhtLpFN1jR755FRQFcOzrrDbh7QhypjdvlYw"
+ "cdAMSZgp9JMHxbM23wPSuH6BOFgxejz35PScZfhDPvTOxIy1jc3MZsWrMC3P324zNolO7JdW"
+ "CX2I5UDKjjaEJfxbgVgJIXxtQGlmj2xkO5sPpjULQV4X2HlY7FQleJ4QRaJIB4buhCA4vUTF"
+ "eMFlxCIYUpTCsal2qsmnGOWa8WCcefrohMjDj1fjzSvSaQwlpyR1GZHF2uPOoQagiCpHpm");
+}
+
+TEST(HashTest, Hash128Misc) {
+ constexpr uint32_t kSeed = 0; // Same as GetSliceHash128
+
+ for (char fill : {'\0', 'a', '1', '\xff', 'e'}) {
+ const size_t max_size = 1000;
+ std::string str(max_size, fill);
+
+ if (fill == 'e') {
+ // Use different characters to check endianness handling
+ for (size_t i = 0; i < str.size(); ++i) {
+ str[i] += static_cast<char>(i);
+ }
+ }
+
+ for (size_t size = 0; size <= max_size; ++size) {
+ Unsigned128 here = Hash128(str.data(), size, kSeed);
+
+ // Must be same as unseeded Hash128 and GetSliceHash128
+ EXPECT_EQ(here, Hash128(str.data(), size));
+ EXPECT_EQ(here, GetSliceHash128(Slice(str.data(), size)));
+ {
+ uint64_t hi, lo;
+ Hash2x64(str.data(), size, &hi, &lo);
+ EXPECT_EQ(Lower64of128(here), lo);
+ EXPECT_EQ(Upper64of128(here), hi);
+ }
+ if (size == 16) {
+ const uint64_t in_hi = DecodeFixed64(str.data() + 8);
+ const uint64_t in_lo = DecodeFixed64(str.data());
+ uint64_t hi, lo;
+ BijectiveHash2x64(in_hi, in_lo, &hi, &lo);
+ EXPECT_EQ(Lower64of128(here), lo);
+ EXPECT_EQ(Upper64of128(here), hi);
+ uint64_t un_hi, un_lo;
+ BijectiveUnhash2x64(hi, lo, &un_hi, &un_lo);
+ EXPECT_EQ(in_lo, un_lo);
+ EXPECT_EQ(in_hi, un_hi);
+ }
+
+ // Upper and Lower must reconstruct hash
+ EXPECT_EQ(here,
+ (Unsigned128{Upper64of128(here)} << 64) | Lower64of128(here));
+ EXPECT_EQ(here,
+ (Unsigned128{Upper64of128(here)} << 64) ^ Lower64of128(here));
+
+ // Seed changes hash value (with high probability)
+ for (uint64_t var_seed = 1; var_seed != 0; var_seed <<= 1) {
+ Unsigned128 seeded = Hash128(str.data(), size, var_seed);
+ EXPECT_NE(here, seeded);
+ // Must match seeded Hash2x64
+ {
+ uint64_t hi, lo;
+ Hash2x64(str.data(), size, var_seed, &hi, &lo);
+ EXPECT_EQ(Lower64of128(seeded), lo);
+ EXPECT_EQ(Upper64of128(seeded), hi);
+ }
+ if (size == 16) {
+ const uint64_t in_hi = DecodeFixed64(str.data() + 8);
+ const uint64_t in_lo = DecodeFixed64(str.data());
+ uint64_t hi, lo;
+ BijectiveHash2x64(in_hi, in_lo, var_seed, &hi, &lo);
+ EXPECT_EQ(Lower64of128(seeded), lo);
+ EXPECT_EQ(Upper64of128(seeded), hi);
+ uint64_t un_hi, un_lo;
+ BijectiveUnhash2x64(hi, lo, var_seed, &un_hi, &un_lo);
+ EXPECT_EQ(in_lo, un_lo);
+ EXPECT_EQ(in_hi, un_hi);
+ }
+ }
+
+ // Size changes hash value (with high probability)
+ size_t max_smaller_by = std::min(size_t{30}, size);
+ for (size_t smaller_by = 1; smaller_by <= max_smaller_by; ++smaller_by) {
+ EXPECT_NE(here, Hash128(str.data(), size - smaller_by, kSeed));
+ }
+ }
+ }
+}
+
+// Test that hash values are "non-trivial" for "trivial" inputs
+TEST(HashTest, Hash128Trivial) {
+ // Thorough test too slow for regression testing
+ constexpr bool thorough = false;
+
+ // For various seeds, make sure hash of empty string is not zero.
+ constexpr uint64_t max_seed = thorough ? 0x1000000 : 0x10000;
+ for (uint64_t seed = 0; seed < max_seed; ++seed) {
+ Unsigned128 here = Hash128("", 0, seed);
+ EXPECT_NE(Lower64of128(here), 0u);
+ EXPECT_NE(Upper64of128(here), 0u);
+ }
+
+ // For standard seed, make sure hash of small strings are not zero
+ constexpr uint32_t kSeed = 0; // Same as GetSliceHash128
+ char input[4];
+ constexpr int max_len = thorough ? 3 : 2;
+ for (int len = 1; len <= max_len; ++len) {
+ for (uint32_t i = 0; (i >> (len * 8)) == 0; ++i) {
+ EncodeFixed32(input, i);
+ Unsigned128 here = Hash128(input, len, kSeed);
+ EXPECT_NE(Lower64of128(here), 0u);
+ EXPECT_NE(Upper64of128(here), 0u);
+ }
+ }
+}
+
+std::string Hash128TestDescriptor(const char *repeat, size_t limit) {
+ const char *mod61_encode =
+ "abcdefghijklmnopqrstuvwxyz123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
+ std::string input;
+ while (input.size() < limit) {
+ input.append(repeat);
+ }
+ std::string rv;
+ for (size_t i = 0; i < limit; ++i) {
+ auto h = GetSliceHash128(Slice(input.data(), i));
+ uint64_t h2 = Upper64of128(h) + Lower64of128(h);
+ rv.append(1, mod61_encode[static_cast<size_t>(h2 % 61)]);
+ }
+ return rv;
+}
+
+// XXH3 changes its algorithm for various sizes up through 250 bytes, so
+// we need to check the stability of larger sizes also.
+TEST(HashTest, Hash128ValueSchema) {
+ // Each of these derives a "descriptor" from the hash values for all
+ // lengths up to 430.
+ // Note that "b" is common for the zero-length string.
+ EXPECT_EQ(
+ Hash128TestDescriptor("foo", 430),
+ "bUMA3As8n9I4vNGhThXlEevxZlyMcbb6TYAlIKJ2f5ponsv99q962rYclQ7u3gfnRdCDQ5JI"
+ "2LrGUaCycbXrvLFe4SjgRb9RQwCfrnmNQ7VSEwSKMnkGCK3bDbXSrnIh5qLXdtvIZklbJpGH"
+ "Dqr93BlqF9ubTnOSYkSdx89XvQqflMIW8bjfQp9BPjQejWOeEQspnN1D3sfgVdFhpaQdHYA5"
+ "pI2XcPlCMFPxvrFuRr7joaDvjNe9IUZaunLPMewuXmC3EL95h52Ju3D7y9RNKhgYxMTrA84B"
+ "yJrMvyjdm3vlBxet4EN7v2GEyjbGuaZW9UL6lrX6PghJDg7ACfLGdxNbH3qXM4zaiG2RKnL5"
+ "S3WXKR78RBB5fRFQ8KDIEQjHFvSNsc3GrAEi6W8P2lv8JMTzjBODO2uN4wadVQFT9wpGfV");
+ // Note that "35D2v" is common for "Rocks"
+ EXPECT_EQ(
+ Hash128TestDescriptor("Rocks", 430),
+ "b35D2vzvklFVDqJmyLRXyApwGGO3EAT3swhe8XJAN3mY2UVPglzdmydxcba6JI2tSvwO6zSu"
+ "ANpjSM7tc9G5iMhsa7R8GfyCXRO1TnLg7HvdWNdgGGBirxZR68BgT7TQsYJt6zyEyISeXI1n"
+ "MXA48Xo7dWfJeYN6Z4KWlqZY7TgFXGbks9AX4ehZNSGtIhdO5i58qlgVX1bEejeOVaCcjC79"
+ "67DrMfOKds7rUQzjBa77sMPcoPW1vu6ljGJPZH3XkRyDMZ1twxXKkNxN3tE8nR7JHwyqBAxE"
+ "fTcjbOWrLZ1irWxRSombD8sGDEmclgF11IxqEhe3Rt7gyofO3nExGckKkS9KfRqsCHbiUyva"
+ "JGkJwUHRXaZnh58b4i1Ei9aQKZjXlvIVDixoZrjcNaH5XJIJlRZce9Z9t82wYapTpckYSg");
+ EXPECT_EQ(
+ Hash128TestDescriptor("RocksDB", 430),
+ "b35D2vFUst3XDZCRlSrhmYYakmqImV97LbBsV6EZlOEQpUPH1d1sD3xMKAPlA5UErHehg5O7"
+ "n966fZqhAf3hRc24kGCLfNAWjyUa7vSNOx3IcPoTyVRFZeFlcCtfl7t1QJumHOCpS33EBmBF"
+ "hvK13QjBbDWYWeHQhJhgV9Mqbx17TIcvUkEnYZxb8IzWNmjVsJG44Z7v52DjGj1ZzS62S2Vv"
+ "qWcDO7apvH5VHg68E9Wl6nXP21vlmUqEH9GeWRehfWVvY7mUpsAg5drHHQyDSdiMceiUuUxJ"
+ "XJqHFcDdzbbPk7xDvbLgWCKvH8k3MpQNWOmbSSRDdAP6nGlDjoTToYkcqVREHJzztSWAAq5h"
+ "GHSUNJ6OxsMHhf8EhXfHtKyUzRmPtjYyeckQcGmrQfFFLidc6cjMDKCdBG6c6HVBrS7H2R");
+}
+
+TEST(FastRange32Test, Values) {
+ using ROCKSDB_NAMESPACE::FastRange32;
+ // Zero range
+ EXPECT_EQ(FastRange32(0, 0), 0U);
+ EXPECT_EQ(FastRange32(123, 0), 0U);
+ EXPECT_EQ(FastRange32(0xffffffff, 0), 0U);
+
+ // One range
+ EXPECT_EQ(FastRange32(0, 1), 0U);
+ EXPECT_EQ(FastRange32(123, 1), 0U);
+ EXPECT_EQ(FastRange32(0xffffffff, 1), 0U);
+
+ // Two range
+ EXPECT_EQ(FastRange32(0, 2), 0U);
+ EXPECT_EQ(FastRange32(123, 2), 0U);
+ EXPECT_EQ(FastRange32(0x7fffffff, 2), 0U);
+ EXPECT_EQ(FastRange32(0x80000000, 2), 1U);
+ EXPECT_EQ(FastRange32(0xffffffff, 2), 1U);
+
+ // Seven range
+ EXPECT_EQ(FastRange32(0, 7), 0U);
+ EXPECT_EQ(FastRange32(123, 7), 0U);
+ EXPECT_EQ(FastRange32(613566756, 7), 0U);
+ EXPECT_EQ(FastRange32(613566757, 7), 1U);
+ EXPECT_EQ(FastRange32(1227133513, 7), 1U);
+ EXPECT_EQ(FastRange32(1227133514, 7), 2U);
+ // etc.
+ EXPECT_EQ(FastRange32(0xffffffff, 7), 6U);
+
+ // Big
+ EXPECT_EQ(FastRange32(1, 0x80000000), 0U);
+ EXPECT_EQ(FastRange32(2, 0x80000000), 1U);
+ EXPECT_EQ(FastRange32(4, 0x7fffffff), 1U);
+ EXPECT_EQ(FastRange32(4, 0x80000000), 2U);
+ EXPECT_EQ(FastRange32(0xffffffff, 0x7fffffff), 0x7ffffffeU);
+ EXPECT_EQ(FastRange32(0xffffffff, 0x80000000), 0x7fffffffU);
+}
+
+TEST(FastRange64Test, Values) {
+ using ROCKSDB_NAMESPACE::FastRange64;
+ // Zero range
+ EXPECT_EQ(FastRange64(0, 0), 0U);
+ EXPECT_EQ(FastRange64(123, 0), 0U);
+ EXPECT_EQ(FastRange64(0xffffFFFF, 0), 0U);
+ EXPECT_EQ(FastRange64(0xffffFFFFffffFFFF, 0), 0U);
+
+ // One range
+ EXPECT_EQ(FastRange64(0, 1), 0U);
+ EXPECT_EQ(FastRange64(123, 1), 0U);
+ EXPECT_EQ(FastRange64(0xffffFFFF, 1), 0U);
+ EXPECT_EQ(FastRange64(0xffffFFFFffffFFFF, 1), 0U);
+
+ // Two range
+ EXPECT_EQ(FastRange64(0, 2), 0U);
+ EXPECT_EQ(FastRange64(123, 2), 0U);
+ EXPECT_EQ(FastRange64(0xffffFFFF, 2), 0U);
+ EXPECT_EQ(FastRange64(0x7fffFFFFffffFFFF, 2), 0U);
+ EXPECT_EQ(FastRange64(0x8000000000000000, 2), 1U);
+ EXPECT_EQ(FastRange64(0xffffFFFFffffFFFF, 2), 1U);
+
+ // Seven range
+ EXPECT_EQ(FastRange64(0, 7), 0U);
+ EXPECT_EQ(FastRange64(123, 7), 0U);
+ EXPECT_EQ(FastRange64(0xffffFFFF, 7), 0U);
+ EXPECT_EQ(FastRange64(2635249153387078802, 7), 0U);
+ EXPECT_EQ(FastRange64(2635249153387078803, 7), 1U);
+ EXPECT_EQ(FastRange64(5270498306774157604, 7), 1U);
+ EXPECT_EQ(FastRange64(5270498306774157605, 7), 2U);
+ EXPECT_EQ(FastRange64(0x7fffFFFFffffFFFF, 7), 3U);
+ EXPECT_EQ(FastRange64(0x8000000000000000, 7), 3U);
+ EXPECT_EQ(FastRange64(0xffffFFFFffffFFFF, 7), 6U);
+
+ // Big but 32-bit range
+ EXPECT_EQ(FastRange64(0x100000000, 0x80000000), 0U);
+ EXPECT_EQ(FastRange64(0x200000000, 0x80000000), 1U);
+ EXPECT_EQ(FastRange64(0x400000000, 0x7fffFFFF), 1U);
+ EXPECT_EQ(FastRange64(0x400000000, 0x80000000), 2U);
+ EXPECT_EQ(FastRange64(0xffffFFFFffffFFFF, 0x7fffFFFF), 0x7fffFFFEU);
+ EXPECT_EQ(FastRange64(0xffffFFFFffffFFFF, 0x80000000), 0x7fffFFFFU);
+
+ // Big, > 32-bit range
+#if SIZE_MAX == UINT64_MAX
+ EXPECT_EQ(FastRange64(0x7fffFFFFffffFFFF, 0x4200000002), 0x2100000000U);
+ EXPECT_EQ(FastRange64(0x8000000000000000, 0x4200000002), 0x2100000001U);
+
+ EXPECT_EQ(FastRange64(0x0000000000000000, 420000000002), 0U);
+ EXPECT_EQ(FastRange64(0x7fffFFFFffffFFFF, 420000000002), 210000000000U);
+ EXPECT_EQ(FastRange64(0x8000000000000000, 420000000002), 210000000001U);
+ EXPECT_EQ(FastRange64(0xffffFFFFffffFFFF, 420000000002), 420000000001U);
+
+ EXPECT_EQ(FastRange64(0xffffFFFFffffFFFF, 0xffffFFFFffffFFFF),
+ 0xffffFFFFffffFFFEU);
+#endif
+}
+
+TEST(FastRangeGenericTest, Values) {
+ using ROCKSDB_NAMESPACE::FastRangeGeneric;
+ // Generic (including big and small)
+ // Note that FastRangeGeneric is also tested indirectly above via
+ // FastRange32 and FastRange64.
+ EXPECT_EQ(
+ FastRangeGeneric(uint64_t{0x8000000000000000}, uint64_t{420000000002}),
+ uint64_t{210000000001});
+ EXPECT_EQ(FastRangeGeneric(uint64_t{0x8000000000000000}, uint16_t{12468}),
+ uint16_t{6234});
+ EXPECT_EQ(FastRangeGeneric(uint32_t{0x80000000}, uint16_t{12468}),
+ uint16_t{6234});
+ // Not recommended for typical use because for example this could fail on
+ // some platforms and pass on others:
+ // EXPECT_EQ(FastRangeGeneric(static_cast<unsigned long>(0x80000000),
+ // uint16_t{12468}),
+ // uint16_t{6234});
+}
+
+// for inspection of disassembly
+uint32_t FastRange32(uint32_t hash, uint32_t range) {
+ return ROCKSDB_NAMESPACE::FastRange32(hash, range);
+}
+
+// for inspection of disassembly
+size_t FastRange64(uint64_t hash, size_t range) {
+ return ROCKSDB_NAMESPACE::FastRange64(hash, range);
+}
+
+// Tests for math.h / math128.h (not worth a separate test binary)
+using ROCKSDB_NAMESPACE::BitParity;
+using ROCKSDB_NAMESPACE::BitsSetToOne;
+using ROCKSDB_NAMESPACE::ConstexprFloorLog2;
+using ROCKSDB_NAMESPACE::CountTrailingZeroBits;
+using ROCKSDB_NAMESPACE::DecodeFixed128;
+using ROCKSDB_NAMESPACE::DecodeFixedGeneric;
+using ROCKSDB_NAMESPACE::DownwardInvolution;
+using ROCKSDB_NAMESPACE::EncodeFixed128;
+using ROCKSDB_NAMESPACE::EncodeFixedGeneric;
+using ROCKSDB_NAMESPACE::FloorLog2;
+using ROCKSDB_NAMESPACE::Lower64of128;
+using ROCKSDB_NAMESPACE::Multiply64to128;
+using ROCKSDB_NAMESPACE::Unsigned128;
+using ROCKSDB_NAMESPACE::Upper64of128;
+
+int blah(int x) { return DownwardInvolution(x); }
+
+template <typename T>
+static void test_BitOps() {
+ // This complex code is to generalize to 128-bit values. Otherwise
+ // we could just use = static_cast<T>(0x5555555555555555ULL);
+ T everyOtherBit = 0;
+ for (unsigned i = 0; i < sizeof(T); ++i) {
+ everyOtherBit = (everyOtherBit << 8) | T{0x55};
+ }
+
+ // This one built using bit operations, as our 128-bit layer
+ // might not implement arithmetic such as subtraction.
+ T vm1 = 0; // "v minus one"
+
+ for (int i = 0; i < int{8 * sizeof(T)}; ++i) {
+ T v = T{1} << i;
+ // If we could directly use arithmetic:
+ // T vm1 = static_cast<T>(v - 1);
+
+ // FloorLog2
+ if (v > 0) {
+ EXPECT_EQ(FloorLog2(v), i);
+ EXPECT_EQ(ConstexprFloorLog2(v), i);
+ }
+ if (vm1 > 0) {
+ EXPECT_EQ(FloorLog2(vm1), i - 1);
+ EXPECT_EQ(ConstexprFloorLog2(vm1), i - 1);
+ EXPECT_EQ(FloorLog2(everyOtherBit & vm1), (i - 1) & ~1);
+ EXPECT_EQ(ConstexprFloorLog2(everyOtherBit & vm1), (i - 1) & ~1);
+ }
+
+ // CountTrailingZeroBits
+ if (v != 0) {
+ EXPECT_EQ(CountTrailingZeroBits(v), i);
+ }
+ if (vm1 != 0) {
+ EXPECT_EQ(CountTrailingZeroBits(vm1), 0);
+ }
+ if (i < int{8 * sizeof(T)} - 1) {
+ EXPECT_EQ(CountTrailingZeroBits(~vm1 & everyOtherBit), (i + 1) & ~1);
+ }
+
+ // BitsSetToOne
+ EXPECT_EQ(BitsSetToOne(v), 1);
+ EXPECT_EQ(BitsSetToOne(vm1), i);
+ EXPECT_EQ(BitsSetToOne(vm1 & everyOtherBit), (i + 1) / 2);
+
+ // BitParity
+ EXPECT_EQ(BitParity(v), 1);
+ EXPECT_EQ(BitParity(vm1), i & 1);
+ EXPECT_EQ(BitParity(vm1 & everyOtherBit), ((i + 1) / 2) & 1);
+
+ // EndianSwapValue
+ T ev = T{1} << (((sizeof(T) - 1 - (i / 8)) * 8) + i % 8);
+ EXPECT_EQ(EndianSwapValue(v), ev);
+
+ // ReverseBits
+ EXPECT_EQ(ReverseBits(v), static_cast<T>(T{1} << (8 * sizeof(T) - 1 - i)));
+#ifdef HAVE_UINT128_EXTENSION // Uses multiplication
+ if (std::is_unsigned<T>::value) { // Technical UB on signed type
+ T rv = T{1} << (8 * sizeof(T) - 1 - i);
+ EXPECT_EQ(ReverseBits(vm1), static_cast<T>(rv * ~T{1}));
+ }
+#endif
+
+ // DownwardInvolution
+ {
+ T misc = static_cast<T>(/*random*/ 0xc682cd153d0e3279U +
+ i * /*random*/ 0x9b3972f3bea0baa3U);
+ if constexpr (sizeof(T) > 8) {
+ misc = (misc << 64) | (/*random*/ 0x52af031a38ced62dU +
+ i * /*random*/ 0x936f803d9752ddc3U);
+ }
+ T misc_masked = misc & vm1;
+ EXPECT_LE(misc_masked, vm1);
+ T di_misc_masked = DownwardInvolution(misc_masked);
+ EXPECT_LE(di_misc_masked, vm1);
+ if (misc_masked > 0) {
+ // Highest-order 1 in same position
+ EXPECT_EQ(FloorLog2(misc_masked), FloorLog2(di_misc_masked));
+ }
+ // Validate involution property on short value
+ EXPECT_EQ(DownwardInvolution(di_misc_masked), misc_masked);
+
+ // Validate involution property on large value
+ T di_misc = DownwardInvolution(misc);
+ EXPECT_EQ(DownwardInvolution(di_misc), misc);
+ // Highest-order 1 in same position
+ if (misc > 0) {
+ EXPECT_EQ(FloorLog2(misc), FloorLog2(di_misc));
+ }
+
+ // Validate distributes over xor.
+ // static_casts to avoid numerical promotion effects.
+ EXPECT_EQ(DownwardInvolution(static_cast<T>(misc_masked ^ vm1)),
+ static_cast<T>(di_misc_masked ^ DownwardInvolution(vm1)));
+ T misc2 = static_cast<T>(misc >> 1);
+ EXPECT_EQ(DownwardInvolution(static_cast<T>(misc ^ misc2)),
+ static_cast<T>(di_misc ^ DownwardInvolution(misc2)));
+
+ // Choose some small number of bits to pull off to test combined
+ // uniqueness guarantee
+ int in_bits = i % 7;
+ unsigned in_mask = (unsigned{1} << in_bits) - 1U;
+ // IMPLICIT: int out_bits = 8 - in_bits;
+ std::vector<bool> seen(256, false);
+ for (int j = 0; j < 255; ++j) {
+ T t_in = misc ^ static_cast<T>(j);
+ unsigned in = static_cast<unsigned>(t_in);
+ unsigned out = static_cast<unsigned>(DownwardInvolution(t_in));
+ unsigned val = ((out << in_bits) | (in & in_mask)) & 255U;
+ EXPECT_FALSE(seen[val]);
+ seen[val] = true;
+ }
+
+ if (i + 8 < int{8 * sizeof(T)}) {
+ // Also test manipulating bits in the middle of input is
+ // bijective in bottom of output
+ seen = std::vector<bool>(256, false);
+ for (int j = 0; j < 255; ++j) {
+ T in = misc ^ (static_cast<T>(j) << i);
+ unsigned val = static_cast<unsigned>(DownwardInvolution(in)) & 255U;
+ EXPECT_FALSE(seen[val]);
+ seen[val] = true;
+ }
+ }
+ }
+
+ vm1 = (vm1 << 1) | 1;
+ }
+
+ EXPECT_EQ(ConstexprFloorLog2(T{1}), 0);
+ EXPECT_EQ(ConstexprFloorLog2(T{2}), 1);
+ EXPECT_EQ(ConstexprFloorLog2(T{3}), 1);
+ EXPECT_EQ(ConstexprFloorLog2(T{42}), 5);
+}
+
+TEST(MathTest, BitOps) {
+ test_BitOps<uint32_t>();
+ test_BitOps<uint64_t>();
+ test_BitOps<uint16_t>();
+ test_BitOps<uint8_t>();
+ test_BitOps<unsigned char>();
+ test_BitOps<unsigned short>();
+ test_BitOps<unsigned int>();
+ test_BitOps<unsigned long>();
+ test_BitOps<unsigned long long>();
+ test_BitOps<char>();
+ test_BitOps<size_t>();
+ test_BitOps<int32_t>();
+ test_BitOps<int64_t>();
+ test_BitOps<int16_t>();
+ test_BitOps<int8_t>();
+ test_BitOps<signed char>();
+ test_BitOps<short>();
+ test_BitOps<int>();
+ test_BitOps<long>();
+ test_BitOps<long long>();
+ test_BitOps<ptrdiff_t>();
+}
+
+TEST(MathTest, BitOps128) { test_BitOps<Unsigned128>(); }
+
+TEST(MathTest, Math128) {
+ const Unsigned128 sixteenHexOnes = 0x1111111111111111U;
+ const Unsigned128 thirtyHexOnes = (sixteenHexOnes << 56) | sixteenHexOnes;
+ const Unsigned128 sixteenHexTwos = 0x2222222222222222U;
+ const Unsigned128 thirtyHexTwos = (sixteenHexTwos << 56) | sixteenHexTwos;
+
+ // v will slide from all hex ones to all hex twos
+ Unsigned128 v = thirtyHexOnes;
+ for (int i = 0; i <= 30; ++i) {
+ // Test bitwise operations
+ EXPECT_EQ(BitsSetToOne(v), 30);
+ EXPECT_EQ(BitsSetToOne(~v), 128 - 30);
+ EXPECT_EQ(BitsSetToOne(v & thirtyHexOnes), 30 - i);
+ EXPECT_EQ(BitsSetToOne(v | thirtyHexOnes), 30 + i);
+ EXPECT_EQ(BitsSetToOne(v ^ thirtyHexOnes), 2 * i);
+ EXPECT_EQ(BitsSetToOne(v & thirtyHexTwos), i);
+ EXPECT_EQ(BitsSetToOne(v | thirtyHexTwos), 60 - i);
+ EXPECT_EQ(BitsSetToOne(v ^ thirtyHexTwos), 60 - 2 * i);
+
+ // Test comparisons
+ EXPECT_EQ(v == thirtyHexOnes, i == 0);
+ EXPECT_EQ(v == thirtyHexTwos, i == 30);
+ EXPECT_EQ(v > thirtyHexOnes, i > 0);
+ EXPECT_EQ(v > thirtyHexTwos, false);
+ EXPECT_EQ(v >= thirtyHexOnes, true);
+ EXPECT_EQ(v >= thirtyHexTwos, i == 30);
+ EXPECT_EQ(v < thirtyHexOnes, false);
+ EXPECT_EQ(v < thirtyHexTwos, i < 30);
+ EXPECT_EQ(v <= thirtyHexOnes, i == 0);
+ EXPECT_EQ(v <= thirtyHexTwos, true);
+
+ // Update v, clearing upper-most byte
+ v = ((v << 12) >> 8) | 0x2;
+ }
+
+ for (int i = 0; i < 128; ++i) {
+ // Test shifts
+ Unsigned128 sl = thirtyHexOnes << i;
+ Unsigned128 sr = thirtyHexOnes >> i;
+ EXPECT_EQ(BitsSetToOne(sl), std::min(30, 32 - i / 4));
+ EXPECT_EQ(BitsSetToOne(sr), std::max(0, 30 - (i + 3) / 4));
+ EXPECT_EQ(BitsSetToOne(sl & sr), i % 2 ? 0 : std::max(0, 30 - i / 2));
+ }
+
+ // Test 64x64->128 multiply
+ Unsigned128 product =
+ Multiply64to128(0x1111111111111111U, 0x2222222222222222U);
+ EXPECT_EQ(Lower64of128(product), 2295594818061633090U);
+ EXPECT_EQ(Upper64of128(product), 163971058432973792U);
+}
+
+TEST(MathTest, Coding128) {
+ const char *in = "_1234567890123456";
+ // Note: in + 1 is likely unaligned
+ Unsigned128 decoded = DecodeFixed128(in + 1);
+ EXPECT_EQ(Lower64of128(decoded), 0x3837363534333231U);
+ EXPECT_EQ(Upper64of128(decoded), 0x3635343332313039U);
+ char out[18];
+ out[0] = '_';
+ EncodeFixed128(out + 1, decoded);
+ out[17] = '\0';
+ EXPECT_EQ(std::string(in), std::string(out));
+}
+
+TEST(MathTest, CodingGeneric) {
+ const char *in = "_1234567890123456";
+ // Decode
+ // Note: in + 1 is likely unaligned
+ Unsigned128 decoded128 = DecodeFixedGeneric<Unsigned128>(in + 1);
+ EXPECT_EQ(Lower64of128(decoded128), 0x3837363534333231U);
+ EXPECT_EQ(Upper64of128(decoded128), 0x3635343332313039U);
+
+ uint64_t decoded64 = DecodeFixedGeneric<uint64_t>(in + 1);
+ EXPECT_EQ(decoded64, 0x3837363534333231U);
+
+ uint32_t decoded32 = DecodeFixedGeneric<uint32_t>(in + 1);
+ EXPECT_EQ(decoded32, 0x34333231U);
+
+ uint16_t decoded16 = DecodeFixedGeneric<uint16_t>(in + 1);
+ EXPECT_EQ(decoded16, 0x3231U);
+
+ // Encode
+ char out[18];
+ out[0] = '_';
+ memset(out + 1, '\0', 17);
+ EncodeFixedGeneric(out + 1, decoded128);
+ EXPECT_EQ(std::string(in), std::string(out));
+
+ memset(out + 1, '\0', 9);
+ EncodeFixedGeneric(out + 1, decoded64);
+ EXPECT_EQ(std::string("_12345678"), std::string(out));
+
+ memset(out + 1, '\0', 5);
+ EncodeFixedGeneric(out + 1, decoded32);
+ EXPECT_EQ(std::string("_1234"), std::string(out));
+
+ memset(out + 1, '\0', 3);
+ EncodeFixedGeneric(out + 1, decoded16);
+ EXPECT_EQ(std::string("_12"), std::string(out));
+}
+
+int main(int argc, char **argv) {
+ fprintf(stderr, "NPHash64 id: %x\n",
+ static_cast<int>(ROCKSDB_NAMESPACE::GetSliceNPHash64("RocksDB")));
+ ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
+ ::testing::InitGoogleTest(&argc, argv);
+
+ return RUN_ALL_TESTS();
+}