412044960a
Prevents us from churning memory by freeing and reallocating a memory block that would have already been adequate as is.
83 lines
2.2 KiB
C++
83 lines
2.2 KiB
C++
// Copyright 2020 yuzu Emulator Project
|
|
// Licensed under GPLv2 or any later version
|
|
// Refer to the license.txt file included.
|
|
|
|
#pragma once
|
|
|
|
#include <type_traits>
|
|
#include <utility>
|
|
|
|
namespace Common {
|
|
|
|
void* AllocateMemoryPages(std::size_t size) noexcept;
|
|
void FreeMemoryPages(void* base, std::size_t size) noexcept;
|
|
|
|
template <typename T>
|
|
class VirtualBuffer final {
|
|
public:
|
|
static_assert(
|
|
std::is_trivially_constructible_v<T>,
|
|
"T must be trivially constructible, as non-trivial constructors will not be executed "
|
|
"with the current allocator");
|
|
|
|
constexpr VirtualBuffer() = default;
|
|
explicit VirtualBuffer(std::size_t count) : alloc_size{count * sizeof(T)} {
|
|
base_ptr = reinterpret_cast<T*>(AllocateMemoryPages(alloc_size));
|
|
}
|
|
|
|
~VirtualBuffer() noexcept {
|
|
FreeMemoryPages(base_ptr, alloc_size);
|
|
}
|
|
|
|
VirtualBuffer(const VirtualBuffer&) = delete;
|
|
VirtualBuffer& operator=(const VirtualBuffer&) = delete;
|
|
|
|
VirtualBuffer(VirtualBuffer&& other) noexcept
|
|
: alloc_size{std::exchange(other.alloc_size, 0)}, base_ptr{std::exchange(other.base_ptr),
|
|
nullptr} {}
|
|
|
|
VirtualBuffer& operator=(VirtualBuffer&& other) noexcept {
|
|
alloc_size = std::exchange(other.alloc_size, 0);
|
|
base_ptr = std::exchange(other.base_ptr, nullptr);
|
|
return *this;
|
|
}
|
|
|
|
void resize(std::size_t count) {
|
|
const auto new_size = count * sizeof(T);
|
|
if (new_size == alloc_size) {
|
|
return;
|
|
}
|
|
|
|
FreeMemoryPages(base_ptr, alloc_size);
|
|
|
|
alloc_size = new_size;
|
|
base_ptr = reinterpret_cast<T*>(AllocateMemoryPages(alloc_size));
|
|
}
|
|
|
|
[[nodiscard]] constexpr const T& operator[](std::size_t index) const {
|
|
return base_ptr[index];
|
|
}
|
|
|
|
[[nodiscard]] constexpr T& operator[](std::size_t index) {
|
|
return base_ptr[index];
|
|
}
|
|
|
|
[[nodiscard]] constexpr T* data() {
|
|
return base_ptr;
|
|
}
|
|
|
|
[[nodiscard]] constexpr const T* data() const {
|
|
return base_ptr;
|
|
}
|
|
|
|
[[nodiscard]] constexpr std::size_t size() const {
|
|
return alloc_size / sizeof(T);
|
|
}
|
|
|
|
private:
|
|
std::size_t alloc_size{};
|
|
T* base_ptr{};
|
|
};
|
|
|
|
} // namespace Common
|