Sönke Holz
d7f65d06d6
This causes GCC and Clang to generate relative loads when accessing global variables instead of using the global offset table (GOT). This saves one load for every global variable access. We unfortunately have to do this by injecting a header into every source file, since "-fvisibility=hidden" doesn't affect `extern` declarations. This additionally means that accessing global variables doesn't depend on relocations anymore, so pre_init code no longer needs to access variables through `adjust_by_mapping_base()`. Next to this, some other small tweaks are required in pre_init because global variables now have the "correct" addresses while we are still identity mapped. Being able to simplify pre_init like this was also the original motivation for this patch. Clang trunk started optimizing `adjust_by_mapping_base()` on AArch64 such that it avoids using the GOT when we attempt to get the address of the global variable in high memory. As a consequence, we now directly get the address in low memory on Clang trunk, causing us to redundantly subtract the physical to link time address offset and end up with an incorrect address. With this patch, we no longer need to rely on the compiler not doing such optimizations anymore. The .got section still exists on non-x86 but only contains 2-3 entries: - the start of the .dynamic section (I'm not sure why), - the __stack_chk_guard (only actually used on RISC-V GCC), - __clz_tab (only on RISC-V GCC). Additionally, there are some other GOT entries caused by the RISC-V `la` pseudo-instruction, which will be removed in the next commit. It's a bit unfortunate that RISC-V GCC still uses the GOT to access the stack protector (__stack_chk_guard), but that's not under our control. RISC-V GCC and AArch64 GCC also still contain a .got.plt section, but none of the other toolchain+architecture combinations.
SerenityOS
Graphical Unix-like operating system for 64-bit x86, Arm, and RISC-V computers.
FAQ | Documentation | Build Instructions
About
SerenityOS is a love letter to '90s user interfaces with a custom Unix-like core. It flatters with sincerity by stealing beautiful ideas from various other systems.
Roughly speaking, the goal is a marriage between the aesthetic of late-1990s productivity software and the power-user accessibility of late-2000s *nix. This is a system by us, for us, based on the things we like.
You can watch videos of the system being developed on YouTube:
Screenshot
Features
- Modern 64-bit kernel with pre-emptive multi-threading
- Browser with JavaScript, WebAssembly, and more (check the spec compliance for JS, CSS, and Wasm)
- Security features (hardware protections, limited userland capabilities, W^X memory,
pledge&unveil, (K)ASLR, OOM-resistance, web-content isolation, state-of-the-art TLS algorithms, ...) - System services (WindowServer, LoginServer, AudioServer, WebServer, RequestServer, CrashServer, ...) and modern IPC
- Good POSIX compatibility (LibC, Shell, syscalls, signals, pseudoterminals, filesystem notifications, standard Unix utilities, ...)
- POSIX-like virtual file systems (/proc, /dev, /sys, /tmp, ...) and ext2 file system
- Network stack and applications with support for IPv4, TCP, UDP; DNS, HTTP, Gemini, IMAP, NTP
- Profiling, debugging and other development tools (Kernel-supported profiling, CrashReporter, interactive GUI playground, HexEditor, HackStudio IDE for C++ and more)
- Libraries for everything from cryptography to OpenGL, audio, JavaScript, GUI, playing chess, ...
- Support for many common and uncommon file formats (PNG, JPEG, GIF, MP3, WAV, FLAC, ZIP, TAR, PDF, QOI, Gemini, ...)
- Unified style and design philosophy, flexible theming system, custom (bitmap and vector) fonts
- Games (Solitaire, Minesweeper, 2048, chess, Conway's Game of Life, ...) and demos (CatDog, Starfield, Eyes, mandelbrot set, WidgetGallery, ...)
- Every-day GUI programs and utilities (Spreadsheet with JavaScript, TextEditor, Terminal, PixelPaint, various multimedia viewers and players, Mail, Assistant, Calculator, ...)
... and all of the above are right in this repository, no extra dependencies, built from-scratch by us :^)
Additionally, there are over three hundred ports of popular open-source software, including games, compilers, Unix tools, multimedia apps and more.
How do I read the documentation?
Man pages are available online at man.serenityos.org. These pages are generated from the Markdown source files in Base/usr/share/man and updated automatically.
When running SerenityOS you can use man for the terminal interface, or help for the GUI.
Code-related documentation can be found in the documentation folder.
How do I build and run this?
See the SerenityOS build instructions or the Ladybird build instructions.
The build system supports a cross-compilation build of SerenityOS from Linux, macOS, Windows (with WSL2) and many other *Nixes. The default build system commands will launch a QEMU instance running the OS with hardware or software virtualization enabled as supported.
Ladybird runs on the same platforms that can be the host for a cross build of SerenityOS and on SerenityOS itself.
Get in touch and participate!
Join our Discord server: SerenityOS Discord
Before opening an issue, please see the issue policy.
A general guide for contributing can be found in CONTRIBUTING.md.
Authors
- Andreas Kling - awesomekling
- Robin Burchell - rburchell
- Conrad Pankoff - deoxxa
- Sergey Bugaev - bugaevc
- Liav A - supercomputer7
- Linus Groh - linusg
- Ali Mohammad Pur - alimpfard
- Shannon Booth - shannonbooth
- Hüseyin ASLITÜRK - asliturk
- Matthew Olsson - mattco98
- Nico Weber - nico
- Brian Gianforcaro - bgianfo
- Ben Wiederhake - BenWiederhake
- Tom - tomuta
- Paul Scharnofske - asynts
- Itamar Shenhar - itamar8910
- Luke Wilde - Lubrsi
- Brendan Coles - bcoles
- Andrew Kaster - ADKaster
- thankyouverycool - thankyouverycool
- Idan Horowitz - IdanHo
- Gunnar Beutner - gunnarbeutner
- Tim Flynn - trflynn89
- Jean-Baptiste Boric - boricj
- Stephan Unverwerth - sunverwerth
- Max Wipfli - MaxWipfli
- Daniel Bertalan - BertalanD
- Jelle Raaijmakers - GMTA
- Sam Atkins - AtkinsSJ
- Tobias Christiansen - TobyAsE
- Lenny Maiorani - ldm5180
- sin-ack - sin-ack
- Jesse Buhagiar - Quaker762
- Peter Elliott - Petelliott
- Karol Kosek - krkk
- Mustafa Quraish - mustafaquraish
- David Tuin - davidot
- Leon Albrecht - Hendiadyoin1
- Tim Schumacher - timschumi
- Marcus Nilsson - metmo
- Gegga Thor - Xexxa
- kleines Filmröllchen - kleinesfilmroellchen
- Kenneth Myhra - kennethmyhra
- Maciej - sppmacd
- Sahan Fernando - ccapitalK
- Benjamin Maxwell - MacDue
- Dennis Esternon - djwisdom
- frhun - frhun
- networkException - networkException
- Brandon Jordan - electrikmilk
- Lucas Chollet - LucasChollet
- Timon Kruiper - FireFox317
- Martin Falisse - martinfalisse
- Gregory Bertilson - Zaggy1024
- Erik Wouters - EWouters
- Rodrigo Tobar - rtobar
- Alexander Kalenik - kalenikaliaksandr
- Tim Ledbetter - tcl3
- Steffen T. Larssen - stelar7
- Andi Gallo - axgallo
- Simon Wanner - skyrising
- FalseHonesty - FalseHonesty
- Bastiaan van der Plaat - bplaat
- Dan Klishch - DanShaders
- Julian Offenhäuser - janso3
- Sönke Holz - spholz
- implicitfield - implicitfield
And many more! See here for a full contributor list. The people listed above have landed more than 100 commits in the project. :^)
License
SerenityOS is licensed under a 2-clause BSD license.