76db9f022d
* Initial skeleton. * Add basic faerie support. This adds enough functionality to enable simple .o file writing through faerie. This included adding the functionality to Module to support RelocSink implementations. * Add basic SimpleJIT support. This adds enough functionality to enable a simple program to be jitted and executed. * Make declare_func_in_func take a Function instead of a Context. It only needs the Function, and sometimes it's useful to call it from places that don't have a full Context. * Temporarily disable local and exported global variables in the Faerie backend. Faerie assumes these variables use pc-relative offset instructions, and Cretonne is not yet emitting those instructions. * FaerieBackend depends on PIC. Faerie itself only supports PIC objects for now, so add an assert to Cretonne to check that it's using a PIC target flag. * SimpleJIT support for data objects. * Preliminary faerie support for data objects. * Support for data objects in faerie using the new colocated flag. * Unit tests for DataContext and friends. * Add a Module::consume() function. This consumes the Module and returns the contained Backend, so that users can call Backend-specific functions with it. For example, the Faerie backend has functions to write an object file. * Update the new crates to version 0.4.4. * Make FaerieBackend own its TargetIsa. This simplifies its interface, as it eliminates a lifetime parameter. While we may eventually want to look into allowing multiple clients to share a TargetIsa, it isn't worth the complexity for FaerieBackend right now. * Don't try to protect faerie from multiple declarations. Let faerie decide for itself whether it wants to consider two declarations to be compatible. * Use debug_assert_eq rather than debug_assert with ==. * Fix FaerieRelocSink's reloc_external to handle data object names. * Relax the asserts in get_function_definition and get_data_definition. These functions don't require definable symbols, but they do require that definable symbols be defined. This is needed for the simplejit backend. * Add a function to the faerie backend to retrieve the artifact name. * Sync up with cretonne changes.
=======================
Cretonne Code Generator
=======================
Cretonne is a low-level retargetable code generator. It translates a `target-independent
intermediate representation <https://cretonne.readthedocs.io/en/latest/langref.html>`_ into executable
machine code.
.. image:: https://readthedocs.org/projects/cretonne/badge/?version=latest
:target: https://cretonne.readthedocs.io/en/latest/?badge=latest
:alt: Documentation Status
.. image:: https://travis-ci.org/cretonne/cretonne.svg?branch=master
:target: https://travis-ci.org/cretonne/cretonne
:alt: Build Status
.. image:: https://badges.gitter.im/cretonne/cretonne.png
:target: https://gitter.im/cretonne/Lobby/~chat
:alt: Gitter chat
For more information, see `the documentation
<https://cretonne.readthedocs.io/en/latest/?badge=latest>`_.
Status
------
Cretonne currently supports enough functionality to run a wide variety of
programs, including all the functionality needed to execute WebAssembly MVP
functions, although it needs to be used within an external WebAssembly
embedding to be part of a complete WebAssembly implementation.
The x86-64 backend is currently the most complete and stable; other
architectures are in various stages of development. Cretonne currently supports
the System V AMD64 ABI calling convention used on many platforms, but does not
yet support the Windows x64 calling convention. The performance of code
produced by Cretonne is not yet impressive, though we have plans to fix that.
The core codegen crates have minimal dependencies, and do not require any host
floating-point support. Support for `no_std` mode in the core codegen crates is
`in development <https://github.com/cretonne/cretonne/tree/no_std>`_.
Cretonne does not yet perform mitigations for Spectre or related security
issues, though it may do so in the future. It does not currently make any
security-relevant instruction timing guarantees. It has seen a fair amount
of testing and fuzzing, although more work is needed before it would be
ready for a production use case.
Cretonne's APIs are not yet stable.
Cretonne currently supports Rust 1.22.1 and later. We intend to always support
the latest *stable* Rust. And, we currently support the version of Rust in the
latest Ubuntu LTS, although whether we will always do so is not yet determined.
Cretonne requires Python 2.7 or Python 3 to build.
Planned uses
------------
Cretonne is designed to be a code generator for WebAssembly, but it is general enough to be useful
elsewhere too. The initial planned uses that affected its design are:
1. `WebAssembly compiler for the SpiderMonkey engine in Firefox
<spidermonkey.rst#phase-1-webassembly>`_.
2. `Backend for the IonMonkey JavaScript JIT compiler in Firefox
<spidermonkey.rst#phase-2-ionmonkey>`_.
3. `Debug build backend for the Rust compiler <rustc.rst>`_.
Building Cretonne
-----------------
Cretonne is using the Cargo package manager format. First, ensure you have
installed a current stable rust (stable, beta, and nightly should all work, but
only stable and beta are tested consistently). Then, change the working
directory to your clone of cretonne and run::
cargo build
This will create a *target/debug* directory where you can find the generated
binary.
To build the optimized binary for release::
cargo build --release
You can then run tests with::
./test-all.sh
You may need to install the *wat2wasm* tool from the `wabt
<https://github.com/WebAssembly/wabt>`_ project in order to run all of the
WebAssembly tests. Tests requiring wat2wasm are ignored if the tool is not
installed.
Building the documentation
--------------------------
To build the Cretonne documentation, you need the `Sphinx documentation
generator <https://www.sphinx-doc.org/>`_::
$ pip install sphinx sphinx-autobuild sphinx_rtd_theme
$ cd cretonne/docs
$ make html
$ open _build/html/index.html
We don't support Sphinx versions before 1.4 since the format of index tuples
has changed.