UUID has been updated to use a better hash and no unnecessary allocations (Big thanks to mosra!)

headers/Types.hpp

@@ -6,18 +6,18 @@
  * v. 2.0. If a copy of the MPL was not distributed with this file, You can
  * obtain one at http://mozilla.org/MPL/2.0/.
  */
+
 #ifndef GUARD_TOURMALINE_TYPES_H
 #define GUARD_TOURMALINE_TYPES_H
+
+#include "TourmalineExternal/random/xoshiro.h"
 #include <cstdint>
 #include <functional>
-#include <memory>
+#include <string>
+
 namespace Tourmaline::Type {
 class UUID {
 public:
-  constexpr static uint8_t BitLength = 128;
-  constexpr static uint8_t QWORDLength = BitLength / 64;
-  constexpr static uint8_t ByteLength = BitLength / 8;
-
   [[nodiscard]]
   std::string asString() const;
   bool operator==(const UUID &rhs) const;
@@ -25,14 +25,8 @@ public:
   UUID(uint64_t firstHalf, uint64_t secondHalf);
   UUID(const std::string &uuid);
 
-  UUID(const UUID &uuid);
-  UUID(UUID &&uuid) noexcept;
-  UUID &operator=(const UUID &uuid);
-  UUID &operator=(UUID &&uuid);
-  ~UUID() = default;
-
 private:
-  std::unique_ptr<uint64_t[]> data = std::make_unique<uint64_t[]>(QWORDLength);
+  uint64_t firstHalf = 0, secondHalf = 0;
   friend struct std::hash<Tourmaline::Type::UUID>;
 };
 } // namespace Tourmaline::Type
@@ -40,10 +34,9 @@ private:
 namespace std {
 template <> struct hash<Tourmaline::Type::UUID> {
   size_t operator()(const Tourmaline::Type::UUID &uuid) const noexcept {
-    const auto data = uuid.data.get();
+    uint64_t hash = Xoshiro::splitmix64(uuid.firstHalf);
-    size_t h1 = std::hash<uint64_t>{}(data[0]),
+    hash += uuid.secondHalf;
-           h2 = std::hash<uint64_t>{}(data[1]);
+    return Xoshiro::splitmix64(hash);
-    return h1 ^ (h2 << 1);
   }
 };
 

source/Types/UUID.cpp

@@ -13,57 +13,27 @@
 #include <cstdint>
 #include <cstring>
 #include <format>
-#include <memory>
 #include <string>
 
 using namespace Tourmaline::Type;
 std::string UUID::asString() const {
-  return std::format("{:016X}{:016X}", data[0], data[1]);
+  return std::format("{:016X}{:016X}", firstHalf, secondHalf);
 }
 
 bool UUID::operator==(const UUID &rhs) const {
   // Since size may be increased
-  for (uint8_t index = 0; index < QWORDLength; index++) {
+  return firstHalf == rhs.firstHalf && secondHalf == rhs.secondHalf;
-    if (this->data[index] != rhs.data[index]) {
-      return false;
-    }
-  }
-  return true;
 }
 
-UUID::UUID(const UUID &uuid) {
+UUID::UUID(uint64_t firstHalf, uint64_t secondHalf)
-  std::memcpy(data.get(), uuid.data.get(), UUID::ByteLength);
+    : firstHalf(firstHalf), secondHalf(secondHalf) {}
-}
-
-UUID &UUID::operator=(const UUID &uuid) {
-  if (this != &uuid) [[likely]] {
-    std::memcpy(data.get(), uuid.data.get(), UUID::ByteLength);
-  }
-
-  return *this;
-}
-
-UUID &UUID::operator=(UUID &&uuid) {
-  if (this != &uuid) [[likely]] {
-    data.swap(uuid.data);
-  }
-
-  return *this;
-}
-
-UUID::UUID(UUID &&uuid) noexcept { data.swap(uuid.data); }
-
-UUID::UUID(uint64_t firstHalf, uint64_t secondHalf) {
-  data[0] = firstHalf;
-  data[1] = secondHalf;
-}
 
 UUID::UUID(const std::string &uuid) {
   // We are assuming that it is a valid UUID, if not then somewhere else this
   // UUID should cause an error
-  auto start = uuid.c_str(), half = start + ByteLength,
+  auto start = uuid.c_str(), half = start + 16,
-       tail = half + ByteLength; // Each UUID element is 16 characters padded
+       tail = half + 16; // Each UUID element is 16 characters padded
 
-  std::from_chars(start, half, data[0], 16);
+  std::from_chars(start, half, firstHalf, 16);
-  std::from_chars(half, tail, data[1], 16);
+  std::from_chars(half, tail, secondHalf, 16);
 }