From cfc34dd41d63f45b0587d089b8ec7fc2ed27c04e Mon Sep 17 00:00:00 2001 From: ameerj <52414509+ameerj@users.noreply.github.com> Date: Sun, 18 Dec 2022 18:08:20 -0500 Subject: [PATCH] common: Add ScratchBuffer class This class creates a default initialized heap allocated buffer for cases where value initializing members during allocation or resize is redundant. --- src/common/CMakeLists.txt | 1 + src/common/scratch_buffer.h | 74 +++++++++++++++++++++++++++++++++++++ 2 files changed, 75 insertions(+) create mode 100644 src/common/scratch_buffer.h diff --git a/src/common/CMakeLists.txt b/src/common/CMakeLists.txt index f558f5a58..eb05e46a8 100644 --- a/src/common/CMakeLists.txt +++ b/src/common/CMakeLists.txt @@ -102,6 +102,7 @@ add_library(common STATIC ${CMAKE_CURRENT_BINARY_DIR}/scm_rev.cpp scm_rev.h scope_exit.h + scratch_buffer.h settings.cpp settings.h settings_input.cpp diff --git a/src/common/scratch_buffer.h b/src/common/scratch_buffer.h new file mode 100644 index 000000000..afbe2eee1 --- /dev/null +++ b/src/common/scratch_buffer.h @@ -0,0 +1,74 @@ +// 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 +class ScratchBuffer { +public: + ScratchBuffer() = default; + + explicit ScratchBuffer(size_t initial_capacity) + : last_requested_size{initial_capacity}, capacity{initial_capacity}, + buffer{Common::make_unique_for_overwrite(initial_capacity)} {} + + ~ScratchBuffer() = default; + + /// This will only grow the buffer's capacity if size is greater than the current capacity. + void resize(size_t size) { + if (size > capacity) { + capacity = size; + buffer = Common::make_unique_for_overwrite(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]] size_t size() const noexcept { + return last_requested_size; + } + +private: + size_t last_requested_size{}; + size_t capacity{}; + std::unique_ptr buffer{}; +}; + +} // namespace Common