improvement: replace (un)likely macro with C++20 attribute (#1516)

* improvement: replace (un)likely macro with C++20 attribute

copying.md

@@ -142,6 +142,7 @@ _the openage authors_ are:
 | Talha Aamir                 | sarcxd                      | sarcxd à gmail dawt com                           |
 | Matthias Geiger             | CountOmega                  | matthias dawt geiger1024 à outlook dawt com       |
 | Yuvraj Tetarwal             | YuviTz1                     | yuvi56789 à gmail dawt com                        |
+| Tarun Samanta               | TS                          | tarunsamanta77@gmail.com                          |
 
 If you're a first-time committer, add yourself to the above list. This is not
 just for legal reasons, but also to keep an overview of all those nicknames.

libopenage/assets/assetmanager.cpp

@@ -181,7 +181,7 @@ void AssetManager::check_updates() {
 
 std::shared_ptr<Texture> AssetManager::get_missing_tex() {
 	// if not loaded, fetch the "missing" texture (big red X).
-	if (unlikely(this->missing_tex.get() == nullptr)) {
+	if (this->missing_tex.get() == nullptr) [[unlikely]] {
 		this->missing_tex = std::make_shared<Texture>(
 			this->asset_path["test"]["textures"]["missing.png"],
 			false);

libopenage/assets/legacy_assetmanager.cpp

@@ -181,7 +181,7 @@ void LegacyAssetManager::check_updates() {
 
 std::shared_ptr<Texture> LegacyAssetManager::get_missing_tex() {
 	// if not loaded, fetch the "missing" texture (big red X).
-	if (unlikely(this->missing_tex.get() == nullptr)) {
+	if (this->missing_tex.get() == nullptr) [[unlikely]] {
 		this->missing_tex = std::make_shared<Texture>(
 			this->asset_path["test"]["textures"]["missing.png"],
 			false);

libopenage/audio/opus_loading.cpp

@@ -1,4 +1,4 @@
-// Copyright 2014-2019 the openage authors. See copying.md for legal info.
+// Copyright 2014-2023 the openage authors. See copying.md for legal info.
 
 #include "opus_loading.h"
 
@@ -30,7 +30,7 @@ static op_seek_func opus_seeker = [](void *stream,
                                      int whence) -> int {
 
 	auto *file = reinterpret_cast<util::File *>(stream);
-	if (unlikely(not file->seekable())) {
+	if (not file->seekable()) [[unlikely]] {
 		return -1;
 	}
 

libopenage/audio/resource.cpp

@@ -1,4 +1,4 @@
-// Copyright 2014-2017 the openage authors. See copying.md for legal info.
+// Copyright 2014-2023 the openage authors. See copying.md for legal info.
 
 #include "resource.h"
 
@@ -32,7 +32,7 @@ int Resource::get_id() const {
 std::shared_ptr<Resource> Resource::create_resource(AudioManager *manager,
                                                     const resource_def &def) {
 
-	if (unlikely(not def.location.is_file())) {
+	if (not def.location.is_file()) [[unlikely]] {
 		throw Error{ERR << "sound file does not exist: " << def.location};
 	}
 

libopenage/datastructure/pairing_heap.h

@@ -1,4 +1,4 @@
-// Copyright 2014-2018 the openage authors. See copying.md for legal info.
+// Copyright 2014-2023 the openage authors. See copying.md for legal info.
 
 #pragma once
 
@@ -256,8 +256,7 @@ class PairingHeap final {
 		// 1. link root children pairwise, last node may be alone
 		element_t first_pair = nullptr;
 		element_t previous_pair = nullptr;
-
-		while (unlikely(current_sibling != nullptr)) {
+		while (current_sibling != nullptr) [[unlikely]] {
 			element_t link0 = current_sibling;
 			element_t link1 = current_sibling->next_sibling;
 
@@ -627,7 +626,7 @@ class PairingHeap final {
 	 * insert a node into the heap.
 	 */
 	void root_insert(const element_t &node) {
-		if (unlikely(this->root_node == nullptr)) {
+		if (this->root_node == nullptr) [[unlikely]] {
 			this->root_node = node;
 		} else {
 			this->root_node = this->root_node->link_with(node);

libopenage/error/error.cpp

@@ -1,4 +1,4 @@
-// Copyright 2013-2021 the openage authors. See copying.md for legal info.
+// Copyright 2013-2023 the openage authors. See copying.md for legal info.
 
 #include "error.h"
 
@@ -22,8 +22,7 @@ Error::Error(const log::message &msg, bool generate_backtrace, bool store_cause)
 	:
 	std::runtime_error{runtime_error_message},
 	msg(msg) {
-
-	if (unlikely(enable_break_on_create)) {
+	if (enable_break_on_create) [[unlikely]] {
 		BREAKPOINT;
 	}
 

libopenage/error/error.h

@@ -1,4 +1,4 @@
-// Copyright 2013-2019 the openage authors. See copying.md for legal info.
+// Copyright 2013-2023 the openage authors. See copying.md for legal info.
 
 #pragma once
 
@@ -152,7 +152,7 @@ inline std::string no_ensuring_message()
 }
 
 // ENSURE(condition, errormessage << variable << etcetc)
-#define ENSURE(...) do { if (unlikely(not OPENAGE_ENS_FIRST(__VA_ARGS__))) { throw ::openage::error::Error(MSG(err) OPENAGE_ENS_REST(__VA_ARGS__)); } } while (0)
+#define ENSURE(...) do { if (not OPENAGE_ENS_FIRST(__VA_ARGS__)) [[unlikely]] { throw ::openage::error::Error(MSG(err) OPENAGE_ENS_REST(__VA_ARGS__)); } } while (0)
 
 /*
  *  expands to the first argument

libopenage/event/eventstore.cpp

@@ -1,4 +1,4 @@
-// Copyright 2018-2018 the openage authors. See copying.md for legal info.
+// Copyright 2018-2023 the openage authors. See copying.md for legal info.
 
 #include "eventstore.h"
 
@@ -13,7 +13,7 @@
 namespace openage::event {
 
 void EventStore::push(const std::shared_ptr<Event> &event) {
-	if (unlikely(event == nullptr)) {
+	if (event == nullptr) [[unlikely]] {
 		throw Error{ERR << "inserting nullptr event to queue"};
 	}
 
@@ -66,7 +66,7 @@ bool EventStore::erase(const std::shared_ptr<Event> &event) {
 
 void EventStore::update(const std::shared_ptr<Event> &event) {
 	auto it = this->events.find(event);
-	if (unlikely(it != std::end(this->events))) {
+	if (it != std::end(this->events)) [[unlikely]] {
 		this->heap.update(it->second);
 	}
 	else {

libopenage/presenter/assets/asset_manager.cpp

@@ -168,7 +168,7 @@ void AssetManager::check_updates() {
 
 std::shared_ptr<Texture> AssetManager::get_missing_tex() {
 	// if not loaded, fetch the "missing" texture (big red X).
-	if (unlikely(this->missing_tex.get() == nullptr)) {
+	if (this->missing_tex.get() == nullptr) [[unlikely]] {
 		this->missing_tex = std::make_shared<Texture>(
 			this->asset_dir["test"]["textures"]["missing.png"],
 			false);

libopenage/pyinterface/exctranslate.cpp

@@ -1,4 +1,4 @@
-// Copyright 2015-2019 the openage authors. See copying.md for legal info.
+// Copyright 2015-2023 the openage authors. See copying.md for legal info.
 
 #include "exctranslate.h"
 
@@ -55,8 +55,7 @@ void translate_exc_cpp_to_py() {
 		throw;
 
 	} catch (PyException &exc) {
-
-		if (unlikely(raise_cpp_pyexception == nullptr)) {
+		if (raise_cpp_pyexception == nullptr) [[unlikely]] {
 			throw Error(MSG(err) <<
 				"raise_pyexception_in_py is uninitialized; "
 				"can't translate C++ exception to Python exception.",
@@ -67,8 +66,7 @@ void translate_exc_cpp_to_py() {
 		raise_cpp_pyexception(&exc);
 
 	} catch (Error &exc) {
-
-		if (unlikely(raise_cpp_error == nullptr)) {
+		if (raise_cpp_error == nullptr) [[unlikely]] {
 			throw Error(MSG(err) <<
 				"raise_error_in_py is uninitialized; "
 				"can't translate C++ exception to Python exception.",
@@ -91,7 +89,7 @@ void translate_exc_cpp_to_py() {
 
 
 void translate_exc_py_to_cpp() {
-	if (unlikely(describe_py_exception == nullptr)) {
+	if (describe_py_exception == nullptr) [[unlikely]] {
 		throw Error(MSG(err) <<
 			"describe_py_exception is uninitialized; "
 			"can't check for and translate Python exception to C++ exception.");

libopenage/pyinterface/functional.h

@@ -109,7 +109,7 @@ class Func {
 	 * raises an Error if this->fptr is still uninitialized.
 	 */
 	inline void check_fptr() const {
-		if (unlikely(not this->fptr)) {
+		if (not this->fptr) [[unlikely]] {
 			throw Error(
 				MSG(err) << "Uninitialized Func object at " <<
 				util::symbol_name(static_cast<const void *>(this)) << ": "

libopenage/pyinterface/pyobject.cpp

@@ -1,4 +1,4 @@
-// Copyright 2015-2019 the openage authors. See copying.md for legal info.
+// Copyright 2015-2023 the openage authors. See copying.md for legal info.
 
 #include "pyobject.h"
 
@@ -101,7 +101,7 @@ PyObjectRef::~PyObjectRef() {
 
 
 void PyObjectRef::set_ref(PyObject *ref) {
-	if (unlikely(this->ref != nullptr)) {
+	if (this->ref != nullptr) [[unlikely]] {
 		py_xdecref.call(this->ref);
 	}
 
@@ -111,7 +111,7 @@ void PyObjectRef::set_ref(PyObject *ref) {
 
 
 void PyObjectRef::set_ref_without_incrementing(PyObject *ref) {
-	if (unlikely(this->ref != nullptr)) {
+	if (this->ref != nullptr) [[unlikely]] {
 		py_xdecref.call(this->ref);
 	}
 
@@ -259,7 +259,7 @@ std::string PyObjectRef::classname() const {
 
 
 std::ostream &operator <<(std::ostream &os, const PyObjectRef &ref) {
-	if (unlikely(ref.get_ref() == nullptr)) {
+	if (ref.get_ref() == nullptr) [[unlikely]] {
 		os << "PyObjectRef[null]";
 	} else {
 		os << "PyObjectRef[" << ref.repr() << "]";

libopenage/pyinterface/setup.cpp

@@ -1,4 +1,4 @@
-// Copyright 2015-2019 the openage authors. See copying.md for legal info.
+// Copyright 2015-2023 the openage authors. See copying.md for legal info.
 
 #include "setup.h"
 
@@ -47,7 +47,7 @@ void add_py_if_component(void *thisptr, std::function<bool ()> checker) {
 	std::unique_lock<std::mutex> lock{checkers.lock};
 
 	// enforce that the object has an associated symbol name.
-	if (unlikely(not util::is_symbol(thisptr))) {
+	if (not util::is_symbol(thisptr)) [[unlikely]] {
 		throw Error(
 			MSG(err) <<
 			"Can't instantiate py interface component as non-global object. " <<

libopenage/renderer/font/font.cpp

@@ -1,4 +1,4 @@
-// Copyright 2015-2019 the openage authors. See copying.md for legal info.
+// Copyright 2015-2023 the openage authors. See copying.md for legal info.
 
 #include "font.h"
 
@@ -112,10 +112,10 @@ Font::Font(FontManager *font_manager, const font_description &description)
 
 void Font::initialize(FT_Library ft_library) {
 	FT_Face ft_face;
-	if (unlikely(FT_New_Face(ft_library, this->description.font_file.c_str(), 0, &ft_face))) {
+	if (FT_New_Face(ft_library, this->description.font_file.c_str(), 0, &ft_face)) [[unlikely]] {
 		throw Error(MSG(err) << "Failed to create font from " << this->description.font_file);
 	}
-	if (unlikely(FT_Set_Char_Size(ft_face, 0, this->description.size * FREETYPE_UNIT, 72, 72))) {
+	if (FT_Set_Char_Size(ft_face, 0, this->description.size * FREETYPE_UNIT, 72, 72)) [[unlikely]] {
 		throw Error(MSG(err) << "Failed to set font face size to " << this->description.size);
 	}
 
@@ -213,7 +213,7 @@ std::vector<codepoint_t> Font::get_glyphs(const std::string &text) const {
 
 std::unique_ptr<unsigned char[]> Font::load_glyph(codepoint_t codepoint, Glyph &glyph) const {
 	FT_Face ft_face = hb_ft_font_get_face(this->hb_font);
-	if (unlikely(FT_Load_Glyph(ft_face, codepoint, FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING | FT_LOAD_RENDER))) {
+	if (FT_Load_Glyph(ft_face, codepoint, FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING | FT_LOAD_RENDER)) [[unlikely]] {
 		return nullptr;
 	}
 

libopenage/renderer/opengl/buffer.cpp

@@ -41,7 +41,7 @@ size_t GlBuffer::get_size() const {
 }
 
 void GlBuffer::upload_data(const uint8_t *data, size_t offset, size_t size) {
-	if (unlikely(offset + size > this->size)) {
+	if (offset + size > this->size) [[unlikely]] {
 		throw Error(MSG(err) << "Tried to upload more data to OpenGL buffer than can fit.");
 	}
 
@@ -50,7 +50,7 @@ void GlBuffer::upload_data(const uint8_t *data, size_t offset, size_t size) {
 }
 
 void GlBuffer::bind(GLenum target) const {
-	if (unlikely(!bool(this->handle))) {
+	if (!bool(this->handle)) [[unlikely]] {
 		throw Error(MSG(err) << "OpenGL buffer has been moved out of.");
 	}
 

libopenage/renderer/opengl/vertex_array.cpp

@@ -95,7 +95,7 @@ GlVertexArray::GlVertexArray(const std::shared_ptr<GlContext> &context,
 			auto const &buf = buf_info.first;
 			auto const &info = buf_info.second;
 
-			if (unlikely(info.get_shader_input_map())) {
+			if (info.get_shader_input_map()) [[unlikely]] {
 				throw Error(MSG(err) << "Shader input mapping is unsupported when constructing a VAO from multiple buffers.");
 			}
 

libopenage/renderer/resources/mesh_data.cpp

@@ -1,4 +1,4 @@
-// Copyright 2017-2021 the openage authors. See copying.md for legal info.
+// Copyright 2017-2023 the openage authors. See copying.md for legal info.
 
 #include "mesh_data.h"
 
@@ -47,7 +47,7 @@ VertexInputInfo::VertexInputInfo(std::vector<vertex_input_t> inputs, vertex_layo
 
 void VertexInputInfo::add_shader_input_map(std::unordered_map<size_t, size_t>&& in_map) {
 	for (auto mapping : in_map) {
-		if (unlikely(mapping.first >= this->inputs.size())) {
+		if (mapping.first >= this->inputs.size()) [[unlikely]] {
 			throw Error(MSG(err) << "A shader input mapping is out-of-range, exceeding the available number of attributes.");
 		}
 	}

libopenage/renderer/resources/parser/parse_blendmask.cpp

@@ -35,7 +35,7 @@ blending_mask parse_mask(const std::vector<std::string> &args) {
 		dir = std::stoul(args[0]);
 	}
 
-	if (unlikely(dir > 255)) {
+	if (dir > 255) [[unlikely]] {
 		throw Error(MSG(err) << "Reading .blmask file failed. Reason: "
 		                     << "directions value " << dir << " is too large");
 	}
@@ -49,7 +49,7 @@ blending_mask parse_mask(const std::vector<std::string> &args) {
 
 BlendPatternInfo parse_blendmask_file(const util::Path &file,
                                       const std::shared_ptr<AssetCache> &cache) {
-	if (unlikely(not file.is_file())) {
+	if (not file.is_file()) [[unlikely]] {
 		throw Error(MSG(err) << "Reading .blmask file '"
 		                     << file.get_name()
 		                     << "' failed. Reason: File not found");
@@ -91,7 +91,7 @@ BlendPatternInfo parse_blendmask_file(const util::Path &file,
 		std::vector<std::string> args{util::split(line, ' ')};
 
 		// TODO: Avoid double lookup with keywordfuncs.find(args[0])
-		if (unlikely(not keywordfuncs.contains(args[0]))) {
+		if (not keywordfuncs.contains(args[0])) [[unlikely]] {
 			throw Error(MSG(err) << "Reading .blmask file '"
 			                     << file.get_name()
 			                     << "' failed. Reason: Keyword "

libopenage/renderer/resources/parser/parse_blendtable.cpp

@@ -60,7 +60,7 @@ PatternData parse_pattern(const std::vector<std::string> &args) {
 
 BlendTableInfo parse_blendtable_file(const util::Path &file,
                                      const std::shared_ptr<AssetCache> &cache) {
-	if (unlikely(not file.is_file())) {
+	if (not file.is_file()) [[unlikely]] {
 		throw Error(MSG(err) << "Reading .bltable file '"
 		                     << file.get_name()
 		                     << "' failed. Reason: File not found");
@@ -99,7 +99,7 @@ BlendTableInfo parse_blendtable_file(const util::Path &file,
 		std::vector<std::string> args{util::split(line, ' ')};
 
 		// TODO: Avoid double lookup with keywordfuncs.find(args[0])
-		if (unlikely(not keywordfuncs.contains(args[0]))) {
+		if (not keywordfuncs.contains(args[0])) [[unlikely]] {
 			throw Error(MSG(err) << "Reading .bltable file '"
 			                     << file.get_name()
 			                     << "' failed. Reason: Keyword "

libopenage/renderer/resources/parser/parse_palette.cpp

@@ -39,7 +39,7 @@ std::vector<uint8_t> parse_colours(const std::vector<std::string> &lines) {
 		for (auto arg : line_args) {
 			auto channel = std::stoul(arg);
 
-			if (unlikely(channel > 255)) {
+			if (channel > 255) [[unlikely]] {
 				throw Error(MSG(err) << "Reading .opal file failed. Reason: "
 				                     << "color channel value " << channel << " is too large");
 			}
@@ -52,7 +52,7 @@ std::vector<uint8_t> parse_colours(const std::vector<std::string> &lines) {
 }
 
 PaletteInfo parse_palette_file(const util::Path &file) {
-	if (unlikely(not file.is_file())) {
+	if (not file.is_file()) [[unlikely]] {
 		throw Error(MSG(err) << "Reading .opal file '"
 		                     << file.get_name()
 		                     << "' failed. Reason: File not found");
@@ -91,7 +91,7 @@ PaletteInfo parse_palette_file(const util::Path &file) {
 		std::vector<std::string> args{util::split(line, ' ')};
 
 		// TODO: Avoid double lookup with keywordfuncs.find(args[0])
-		if (unlikely(not keywordfuncs.contains(args[0]))) {
+		if (not keywordfuncs.contains(args[0])) [[unlikely]] {
 			throw Error(MSG(err) << "Reading .opal file '"
 			                     << file.get_name()
 			                     << "' failed. Reason: Keyword "