RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-10-31 00:42:44 +00:00
Code Issues Activity Actions

Kernel: Change static constexpr variables to constexpr where possible

Browse source 
Function-local `static constexpr` variables can be `constexpr`. This
can reduce memory consumption, binary size, and offer additional
compiler optimizations.

These changes result in a stripped x86_64 kernel binary size reduction
of 592 bytes.
This commit is contained in:
Lenny Maiorani 2022-02-09 11:33:39 -07:00 • committed by Linus Groh
parent 6a4c8a66ae
commit c6acf64558
11 changed files with 26 additions and 15 deletions
Download patch file Download diff file Expand all files Collapse all files

3
Kernel/Arch/x86/common/Processor.cpp
View file

@ -1,5 +1,6 @@
/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -514,7 +515,7 @@ ErrorOr<Vector<FlatPtr, 32>> Processor::capture_stack_trace(Thread& thread, size
Vector<FlatPtr, 32> stack_trace;
auto walk_stack = [&](FlatPtr stack_ptr) -> ErrorOr<void> {
static constexpr size_t max_stack_frames = 4096;
constexpr size_t max_stack_frames = 4096;
bool is_walking_userspace_stack = false;
TRY(stack_trace.try_append(ip));
size_t count = 1;

3
Kernel/Firmware/ACPI/Parser.cpp
View file

@ -1,6 +1,7 @@
/*
* Copyright (c) 2020-2021, Liav A. <liavalb@hotmail.co.il>
* Copyright (c) 2020-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -395,7 +396,7 @@ static bool validate_table(const Structures::SDTHeader& v_header, size_t length)
// https://uefi.org/specs/ACPI/6.4/05_ACPI_Software_Programming_Model/ACPI_Software_Programming_Model.html#finding-the-rsdp-on-ia-pc-systems
UNMAP_AFTER_INIT Optional<PhysicalAddress> StaticParsing::find_rsdp()
{
static constexpr auto signature = "RSD PTR "sv;
constexpr auto signature = "RSD PTR "sv;
auto ebda_or_error = map_ebda();
if (!ebda_or_error.is_error()) {
auto rsdp = ebda_or_error.value().find_chunk_starting_with(signature, 16);

3
Kernel/Firmware/MultiProcessor/Parser.cpp
View file

@ -1,6 +1,7 @@
/*
* Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -86,7 +87,7 @@ UNMAP_AFTER_INIT void MultiProcessorParser::parse_configuration_table()
UNMAP_AFTER_INIT Optional<PhysicalAddress> MultiProcessorParser::find_floating_pointer()
{
static constexpr auto signature = "_MP_"sv;
constexpr auto signature = "_MP_"sv;
auto ebda_or_error = map_ebda();
if (!ebda_or_error.is_error()) {
auto mp_floating_pointer = ebda_or_error.value().find_chunk_starting_with(signature, 16);

3
Kernel/Graphics/VirtIOGPU/FramebufferDevice.cpp
View file

@ -1,5 +1,6 @@
/*
* Copyright (c) 2021, Sahan Fernando <sahan.h.fernando@gmail.com>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -342,7 +343,7 @@ void FramebufferDevice::clear_to_black(Buffer& buffer)
void FramebufferDevice::draw_ntsc_test_pattern(Buffer& buffer)
{
static constexpr u8 colors[12][4] = {
constexpr u8 colors[12][4] = {
{ 0xff, 0xff, 0xff, 0xff }, // White
{ 0x00, 0xff, 0xff, 0xff }, // Primary + Composite colors
{ 0xff, 0xff, 0x00, 0xff },

3
Kernel/Memory/VirtualRangeAllocator.cpp
View file

@ -1,5 +1,6 @@
/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -68,7 +69,7 @@ ErrorOr<VirtualRange> VirtualRangeAllocator::try_allocate_randomized(size_t size
VERIFY((alignment % PAGE_SIZE) == 0);
// FIXME: I'm sure there's a smarter way to do this.
static constexpr size_t maximum_randomization_attempts = 1000;
constexpr size_t maximum_randomization_attempts = 1000;
for (size_t i = 0; i < maximum_randomization_attempts; ++i) {
VirtualAddress random_address { round_up_to_power_of_two(get_fast_random<FlatPtr>() % m_total_range.end().get(), alignment) };

3
Kernel/Prekernel/Arch/aarch64/init.cpp
View file

@ -2,6 +2,7 @@
* Copyright (c) 2021, Nico Weber <thakis@chromium.org>
* Copyright (c) 2021, Marcin Undak <mcinek@gmail.com>
* Copyright (c) 2021, Jesse Buhagiar <jooster669@gmail.com>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -99,7 +100,7 @@ void __stack_chk_fail()
extern "C" void exception_common(TrapFrame const* const trap_frame)
{
static constexpr bool print_stack_frame = true;
constexpr bool print_stack_frame = true;
if constexpr (print_stack_frame) {
auto& uart = Prekernel::UART::the();

3
Kernel/Storage/NVMe/NVMeController.cpp
View file

@ -1,5 +1,6 @@
/*
* Copyright (c) 2021, Pankaj R <pankydev8@gmail.com>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -71,7 +72,7 @@ UNMAP_AFTER_INIT ErrorOr<void> NVMeController::initialize(bool is_queue_polled)
bool NVMeController::wait_for_ready(bool expected_ready_bit_value)
{
static constexpr size_t one_ms_io_delay = 1000;
constexpr size_t one_ms_io_delay = 1000;
auto wait_iterations = m_ready_timeout.to_milliseconds();
u32 expected_rdy = expected_ready_bit_value ? 1 : 0;

3
Kernel/Storage/StorageManagement.cpp
View file

@ -1,5 +1,6 @@
/*
* Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -57,7 +58,7 @@ UNMAP_AFTER_INIT void StorageManagement::enumerate_controllers(bool force_pio, b
}
{
static constexpr PCI::HardwareID vmd_device = { 0x8086, 0x9a0b };
constexpr PCI::HardwareID vmd_device = { 0x8086, 0x9a0b };
if (device_identifier.hardware_id() == vmd_device) {
auto controller = PCI::VolumeManagementDevice::must_create(device_identifier);
PCI::Access::the().add_host_controller_and_enumerate_attached_devices(move(controller), [this, nvme_poll](PCI::DeviceIdentifier const& device_identifier) -> void {

3
Kernel/Syscall.cpp
View file

@ -1,5 +1,6 @@
/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -196,7 +197,7 @@ NEVER_INLINE void syscall_handler(TrapFrame* trap)
asm volatile(""
: "=m"(*ptr));
static constexpr FlatPtr iopl_mask = 3u << 12;
constexpr FlatPtr iopl_mask = 3u << 12;
FlatPtr flags = regs.flags();
if ((flags & (iopl_mask)) != 0) {

5
Kernel/Syscalls/execve.cpp
View file

@ -1,5 +1,6 @@
/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -57,8 +58,8 @@ static bool validate_stack_size(NonnullOwnPtrVector<KString> const& arguments, N
total_arguments_size += sizeof(char*) * (arguments.size() + 1);
total_environment_size += sizeof(char*) * (environment.size() + 1);
static constexpr size_t max_arguments_size = Thread::default_userspace_stack_size / 8;
static constexpr size_t max_environment_size = Thread::default_userspace_stack_size / 8;
constexpr size_t max_arguments_size = Thread::default_userspace_stack_size / 8;
constexpr size_t max_environment_size = Thread::default_userspace_stack_size / 8;
if (total_arguments_size > max_arguments_size)
return false;

9
Kernel/TTY/TTY.cpp
View file

@ -1,5 +1,6 @@
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -403,7 +404,7 @@ ErrorOr<void> TTY::set_termios(const termios& t)
StringView name;
};
static constexpr FlagDescription unimplemented_iflags[] = {
constexpr FlagDescription unimplemented_iflags[] = {
{ IGNBRK, "IGNBRK" },
{ BRKINT, "BRKINT" },
{ IGNPAR, "IGNPAR" },
@ -424,7 +425,7 @@ ErrorOr<void> TTY::set_termios(const termios& t)
}
}
static constexpr FlagDescription unimplemented_oflags[] = {
constexpr FlagDescription unimplemented_oflags[] = {
{ OLCUC, "OLCUC" },
{ ONOCR, "ONOCR" },
{ ONLRET, "ONLRET" },
@ -443,7 +444,7 @@ ErrorOr<void> TTY::set_termios(const termios& t)
rc = ENOTIMPL;
}
static constexpr FlagDescription unimplemented_cflags[] = {
constexpr FlagDescription unimplemented_cflags[] = {
{ CSTOPB, "CSTOPB" },
{ CREAD, "CREAD" },
{ PARENB, "PARENB" },
@ -458,7 +459,7 @@ ErrorOr<void> TTY::set_termios(const termios& t)
}
}
static constexpr FlagDescription unimplemented_lflags[] = {
constexpr FlagDescription unimplemented_lflags[] = {
{ TOSTOP, "TOSTOP" },
{ IEXTEN, "IEXTEN" }
};