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Diffstat (limited to 'src/common/scratch_buffer.h')
-rw-r--r-- | src/common/scratch_buffer.h | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/src/common/scratch_buffer.h b/src/common/scratch_buffer.h new file mode 100644 index 000000000..1245a5086 --- /dev/null +++ b/src/common/scratch_buffer.h @@ -0,0 +1,95 @@ +// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project +// SPDX-License-Identifier: GPL-2.0-or-later + +#pragma once + +#include "common/make_unique_for_overwrite.h" + +namespace Common { + +/** + * ScratchBuffer class + * This class creates a default initialized heap allocated buffer for cases such as intermediate + * buffers being copied into entirely, where value initializing members during allocation or resize + * is redundant. + */ +template <typename T> +class ScratchBuffer { +public: + ScratchBuffer() = default; + + explicit ScratchBuffer(size_t initial_capacity) + : last_requested_size{initial_capacity}, buffer_capacity{initial_capacity}, + buffer{Common::make_unique_for_overwrite<T[]>(initial_capacity)} {} + + ~ScratchBuffer() = default; + + /// This will only grow the buffer's capacity if size is greater than the current capacity. + /// The previously held data will remain intact. + void resize(size_t size) { + if (size > buffer_capacity) { + auto new_buffer = Common::make_unique_for_overwrite<T[]>(size); + std::move(buffer.get(), buffer.get() + buffer_capacity, new_buffer.get()); + buffer = std::move(new_buffer); + buffer_capacity = size; + } + last_requested_size = size; + } + + /// This will only grow the buffer's capacity if size is greater than the current capacity. + /// The previously held data will be destroyed if a reallocation occurs. + void resize_destructive(size_t size) { + if (size > buffer_capacity) { + buffer_capacity = size; + buffer = Common::make_unique_for_overwrite<T[]>(buffer_capacity); + } + last_requested_size = size; + } + + [[nodiscard]] T* data() noexcept { + return buffer.get(); + } + + [[nodiscard]] const T* data() const noexcept { + return buffer.get(); + } + + [[nodiscard]] T* begin() noexcept { + return data(); + } + + [[nodiscard]] const T* begin() const noexcept { + return data(); + } + + [[nodiscard]] T* end() noexcept { + return data() + last_requested_size; + } + + [[nodiscard]] const T* end() const noexcept { + return data() + last_requested_size; + } + + [[nodiscard]] T& operator[](size_t i) { + return buffer[i]; + } + + [[nodiscard]] const T& operator[](size_t i) const { + return buffer[i]; + } + + [[nodiscard]] size_t size() const noexcept { + return last_requested_size; + } + + [[nodiscard]] size_t capacity() const noexcept { + return buffer_capacity; + } + +private: + size_t last_requested_size{}; + size_t buffer_capacity{}; + std::unique_ptr<T[]> buffer{}; +}; + +} // namespace Common |