Merge pull request #2016 from Ivorforce/localvector-10.x

Sync `LocalVector` with upstream Godot

Author: dsnopek

include/godot_cpp/core/method_bind.hpp

@@ -111,7 +111,7 @@ class MethodBind {
 	}
 
 	void set_argument_names(const LocalVector<StringName> &p_names);
-	LocalVector<StringName> get_argument_names() const;
+	const LocalVector<StringName> &get_argument_names() const;
 
 	virtual GDExtensionClassMethodArgumentMetadata get_argument_metadata(int p_argument) const = 0;
 

include/godot_cpp/templates/local_vector.hpp

@@ -46,32 +46,48 @@ namespace godot {
 // Otherwise, it grows exponentially (the default and what you want in most cases).
 template <typename T, typename U = uint32_t, bool force_trivial = false, bool tight = false>
 class LocalVector {
+	static_assert(!force_trivial, "force_trivial is no longer supported. Use resize_uninitialized instead.");
+
 private:
 	U count = 0;
 	U capacity = 0;
 	T *data = nullptr;
 
+	template <bool p_init>
+	void _resize(U p_size) {
+		if (p_size < count) {
+			if constexpr (!std::is_trivially_destructible_v<T>) {
+				for (U i = p_size; i < count; i++) {
+					data[i].~T();
+				}
+			}
+			count = p_size;
+		} else if (p_size > count) {
+			reserve(p_size);
+			if constexpr (p_init) {
+				memnew_arr_placement(data + count, p_size - count);
+			} else {
+				static_assert(std::is_trivially_destructible_v<T>, "T must be trivially destructible to resize uninitialized");
+			}
+			count = p_size;
+		}
+	}
+
 public:
-	_FORCE_INLINE_ T *ptr() { return data; }
-	_FORCE_INLINE_ const T *ptr() const { return data; }
+	_FORCE_INLINE_ T *ptr() _LIFETIME_BOUND_ { return data; }
+	_FORCE_INLINE_ const T *ptr() const _LIFETIME_BOUND_ { return data; }
 	_FORCE_INLINE_ U size() const { return count; }
 
-	_FORCE_INLINE_ Span<T> span() const { return Span(data, count); }
-	_FORCE_INLINE_ operator Span<T>() const { return span(); }
+	_FORCE_INLINE_ Span<T> span() const _LIFETIME_BOUND_ { return Span(data, count); }
+	_FORCE_INLINE_ operator Span<T>() const _LIFETIME_BOUND_ { return span(); }
 
 	// Must take a copy instead of a reference (see GH-31736).
 	_FORCE_INLINE_ void push_back(T p_elem) {
 		if (unlikely(count == capacity)) {
-			capacity = tight ? (capacity + 1) : MAX((U)1, capacity << 1);
-			data = (T *)memrealloc(data, capacity * sizeof(T));
-			CRASH_COND_MSG(!data, "Out of memory");
+			reserve(count + 1);
 		}
 
-		if constexpr (!std::is_trivially_constructible_v<T> && !force_trivial) {
-			memnew_placement(&data[count++], T(p_elem));
-		} else {
-			data[count++] = std::move(p_elem);
-		}
+		memnew_placement(&data[count++], T(std::move(p_elem)));
 	}
 
 	void remove_at(U p_index) {
@@ -80,9 +96,7 @@ class LocalVector {
 		for (U i = p_index; i < count; i++) {
 			data[i] = std::move(data[i + 1]);
 		}
-		if constexpr (!std::is_trivially_destructible_v<T> && !force_trivial) {
-			data[count].~T();
-		}
+		data[count].~T();
 	}
 
 	/// Removes the item copying the last value into the position of the one to
@@ -93,9 +107,7 @@ class LocalVector {
 		if (count > p_index) {
 			data[p_index] = std::move(data[count]);
 		}
-		if constexpr (!std::is_trivially_destructible_v<T> && !force_trivial) {
-			data[count].~T();
-		}
+		data[count].~T();
 	}
 
 	_FORCE_INLINE_ bool erase(const T &p_val) {
@@ -107,6 +119,15 @@ class LocalVector {
 		return false;
 	}
 
+	bool erase_unordered(const T &p_val) {
+		int64_t idx = find(p_val);
+		if (idx >= 0) {
+			remove_at_unordered(idx);
+			return true;
+		}
+		return false;
+	}
+
 	U erase_multiple_unordered(const T &p_val) {
 		U from = 0;
 		U occurrences = 0;
@@ -123,11 +144,14 @@ class LocalVector {
 		return occurrences;
 	}
 
-	void invert() {
+	void reverse() {
 		for (U i = 0; i < count / 2; i++) {
 			SWAP(data[i], data[count - i - 1]);
 		}
 	}
+#ifndef DISABLE_DEPRECATED
+	[[deprecated("Use reverse() instead")]] void invert() { reverse(); }
+#endif
 
 	_FORCE_INLINE_ void clear() { resize(0); }
 	_FORCE_INLINE_ void reset() {
@@ -140,42 +164,48 @@ class LocalVector {
 	}
 	_FORCE_INLINE_ bool is_empty() const { return count == 0; }
 	_FORCE_INLINE_ U get_capacity() const { return capacity; }
-	_FORCE_INLINE_ void reserve(U p_size) {
-		p_size = tight ? p_size : Math::nearest_power_of_2_templated(p_size);
+	void reserve(U p_size) {
 		if (p_size > capacity) {
-			capacity = p_size;
+			if (tight) {
+				capacity = p_size;
+			} else {
+				// Try 1.5x the current capacity.
+				// This ratio was chosen because it is close to the ideal growth rate of the golden ratio.
+				// See https://archive.ph/Z2R8w for details.
+				capacity = MAX((U)2, capacity + ((1 + capacity) >> 1));
+				// If 1.5x growth isn't enough, just use the needed size exactly.
+				if (p_size > capacity) {
+					capacity = p_size;
+				}
+			}
 			data = (T *)memrealloc(data, capacity * sizeof(T));
 			CRASH_COND_MSG(!data, "Out of memory");
+		} else if (p_size < count) {
+			WARN_VERBOSE("reserve() called with a capacity smaller than the current size. This is likely a mistake.");
 		}
 	}
 
+	/// Resize the vector.
+	/// Elements are initialized (or not) depending on what the default C++ behavior for T is.
+	/// Note: If force_trivial is set, this will behave like resize_uninitialized instead.
 	void resize(U p_size) {
-		if (p_size < count) {
-			if constexpr (!std::is_trivially_destructible_v<T> && !force_trivial) {
-				for (U i = p_size; i < count; i++) {
-					data[i].~T();
-				}
-			}
-			count = p_size;
-		} else if (p_size > count) {
-			if (unlikely(p_size > capacity)) {
-				capacity = tight ? p_size : Math::nearest_power_of_2_templated(p_size);
-				data = (T *)memrealloc(data, capacity * sizeof(T));
-				CRASH_COND_MSG(!data, "Out of memory");
-			}
-			if constexpr (!std::is_trivially_constructible_v<T> && !force_trivial) {
-				for (U i = count; i < p_size; i++) {
-					memnew_placement(&data[i], T);
-				}
-			}
-			count = p_size;
-		}
+		// Don't init when trivially constructible.
+		_resize<!std::is_trivially_constructible_v<T>>(p_size);
 	}
-	_FORCE_INLINE_ const T &operator[](U p_index) const {
+
+	/// Resize and set new values to 0 / false / nullptr.
+	_FORCE_INLINE_ void resize_initialized(U p_size) { _resize<true>(p_size); }
+
+	/// Resize and keep memory uninitialized.
+	/// This means that any newly added elements have an unknown value, and are expected to be set after the `resize_uninitialized` call.
+	/// This is only available for trivially destructible types (otherwise, trivial resize might be UB).
+	_FORCE_INLINE_ void resize_uninitialized(U p_size) { _resize<false>(p_size); }
+
+	_FORCE_INLINE_ const T &operator[](U p_index) const _LIFETIME_BOUND_ {
 		CRASH_BAD_UNSIGNED_INDEX(p_index, count);
 		return data[p_index];
 	}
-	_FORCE_INLINE_ T &operator[](U p_index) {
+	_FORCE_INLINE_ T &operator[](U p_index) _LIFETIME_BOUND_ {
 		CRASH_BAD_UNSIGNED_INDEX(p_index, count);
 		return data[p_index];
 	}
@@ -230,17 +260,17 @@ class LocalVector {
 		const T *elem_ptr = nullptr;
 	};
 
-	_FORCE_INLINE_ Iterator begin() {
+	_FORCE_INLINE_ Iterator begin() _LIFETIME_BOUND_ {
 		return Iterator(data);
 	}
-	_FORCE_INLINE_ Iterator end() {
+	_FORCE_INLINE_ Iterator end() _LIFETIME_BOUND_ {
 		return Iterator(data + size());
 	}
 
-	_FORCE_INLINE_ ConstIterator begin() const {
+	_FORCE_INLINE_ ConstIterator begin() const _LIFETIME_BOUND_ {
 		return ConstIterator(ptr());
 	}
-	_FORCE_INLINE_ ConstIterator end() const {
+	_FORCE_INLINE_ ConstIterator end() const _LIFETIME_BOUND_ {
 		return ConstIterator(ptr() + size());
 	}
 
@@ -257,13 +287,14 @@ class LocalVector {
 		}
 	}
 
-	int64_t find(const T &p_val, U p_from = 0) const {
-		for (U i = p_from; i < count; i++) {
-			if (data[i] == p_val) {
-				return int64_t(i);
-			}
+	int64_t find(const T &p_val, int64_t p_from = 0) const {
+		if (p_from < 0) {
+			p_from = size() + p_from;
 		}
-		return -1;
+		if (p_from < 0 || p_from >= size()) {
+			return -1;
+		}
+		return span().find(p_val, p_from);
 	}
 
 	bool has(const T &p_val) const {
@@ -282,7 +313,7 @@ class LocalVector {
 	}
 
 	void sort() {
-		sort_custom<_DefaultComparator<T>>();
+		sort_custom<Comparator<T>>();
 	}
 
 	void ordered_insert(T p_val) {
@@ -295,22 +326,6 @@ class LocalVector {
 		insert(i, p_val);
 	}
 
-	operator Vector<T>() const {
-		Vector<T> ret;
-		ret.resize(count);
-		T *w = ret.ptrw();
-		if (w) {
-			if constexpr (std::is_trivially_copyable_v<T>) {
-				memcpy(w, data, sizeof(T) * count);
-			} else {
-				for (U i = 0; i < count; i++) {
-					w[i] = data[i];
-				}
-			}
-		}
-		return ret;
-	}
-
 	Vector<uint8_t> to_byte_array() const { //useful to pass stuff to gpu or variant
 		Vector<uint8_t> ret;
 		ret.resize(count * sizeof(T));
@@ -328,7 +343,7 @@ class LocalVector {
 			push_back(element);
 		}
 	}
-	_FORCE_INLINE_ LocalVector(const LocalVector &p_from) {
+	_FORCE_INLINE_ explicit LocalVector(const LocalVector &p_from) {
 		resize(p_from.size());
 		for (U i = 0; i < p_from.count; i++) {
 			data[i] = p_from.data[i];
@@ -384,7 +399,11 @@ class LocalVector {
 	}
 };
 
-template <typename T, typename U = uint32_t, bool force_trivial = false>
-using TightLocalVector = LocalVector<T, U, force_trivial, true>;
+template <typename T, typename U = uint32_t>
+using TightLocalVector = LocalVector<T, U, false, true>;
+
+// Zero-constructing LocalVector initializes count, capacity and data to 0 and thus empty.
+template <typename T, typename U, bool force_trivial, bool tight>
+struct is_zero_constructible<LocalVector<T, U, force_trivial, tight>> : std::true_type {};
 
 } // namespace godot

src/core/method_bind.cpp

@@ -60,7 +60,7 @@ void MethodBind::set_argument_names(const LocalVector<StringName> &p_names) {
 	argument_names = p_names;
 }
 
-LocalVector<StringName> MethodBind::get_argument_names() const {
+const LocalVector<StringName> &MethodBind::get_argument_names() const {
 	return argument_names;
 }