Common: implement MultiLevelPageTable.

src/common/multi_level_page_table.h

@@ -0,0 +1,79 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include "common/common_types.h"
+
+namespace Common {
+
+template <typename BaseAddr>
+class MultiLevelPageTable final {
+public:
+    constexpr MultiLevelPageTable() = default;
+    explicit MultiLevelPageTable(std::size_t address_space_bits, std::size_t first_level_bits,
+                                 std::size_t page_bits);
+
+    ~MultiLevelPageTable() noexcept;
+
+    MultiLevelPageTable(const MultiLevelPageTable&) = delete;
+    MultiLevelPageTable& operator=(const MultiLevelPageTable&) = delete;
+
+    MultiLevelPageTable(MultiLevelPageTable&& other) noexcept
+        : address_space_bits{std::exchange(other.address_space_bits, 0)},
+          first_level_bits{std::exchange(other.first_level_bits, 0)}, page_bits{std::exchange(
+                                                                          other.page_bits, 0)},
+          first_level_shift{std::exchange(other.first_level_shift, 0)},
+          first_level_chunk_size{std::exchange(other.first_level_chunk_size, 0)},
+          first_level_map{std::move(other.first_level_map)}, base_ptr{std::exchange(other.base_ptr,
+                                                                                    nullptr)} {}
+
+    MultiLevelPageTable& operator=(MultiLevelPageTable&& other) noexcept {
+        address_space_bits = std::exchange(other.address_space_bits, 0);
+        first_level_bits = std::exchange(other.first_level_bits, 0);
+        page_bits = std::exchange(other.page_bits, 0);
+        first_level_shift = std::exchange(other.first_level_shift, 0);
+        first_level_chunk_size = std::exchange(other.first_level_chunk_size, 0);
+        alloc_size = std::exchange(other.alloc_size, 0);
+        first_level_map = std::move(other.first_level_map);
+        base_ptr = std::exchange(other.base_ptr, nullptr);
+        return *this;
+    }
+
+    void ReserveRange(u64 start, std::size_t size);
+
+    [[nodiscard]] constexpr const BaseAddr& operator[](std::size_t index) const {
+        return base_ptr[index];
+    }
+
+    [[nodiscard]] constexpr BaseAddr& operator[](std::size_t index) {
+        return base_ptr[index];
+    }
+
+    [[nodiscard]] constexpr BaseAddr* data() {
+        return base_ptr;
+    }
+
+    [[nodiscard]] constexpr const BaseAddr* data() const {
+        return base_ptr;
+    }
+
+private:
+    void AllocateLevel(u64 level);
+
+    std::size_t address_space_bits{};
+    std::size_t first_level_bits{};
+    std::size_t page_bits{};
+    std::size_t first_level_shift{};
+    std::size_t first_level_chunk_size{};
+    std::size_t alloc_size{};
+    std::vector<void*> first_level_map{};
+    BaseAddr* base_ptr{};
+};
+
+} // namespace Common