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=======================
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Cretonne Code Generator
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=======================
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Cretonne is a low-level retargetable code generator. It translates a
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target-independent intermediate language into executable machine code.
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.. image:: https://readthedocs.org/projects/cretonne/badge/?version=latest
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:target: https://cretonne.readthedocs.io/en/latest/?badge=latest
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:alt: Documentation Status
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.. image:: https://travis-ci.org/stoklund/cretonne.svg?branch=master
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:target: https://travis-ci.org/stoklund/cretonne
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:alt: Build Status
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Cretonne is designed to be a code generator for WebAssembly with these design
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goals:
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No undefined behavior
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Cretonne does not have a nasal demons clause, and it won't generate code
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with unexpected behavior if invariants are broken.
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Portable semantics
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As far as possible, Cretonne's input language has well-defined semantics
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that are the same on all target architectures. The semantics are usually
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the same as WebAssembly's.
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Fast sandbox verification
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Cretonne's input language has a safe subset for sandboxed code. No advanced
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analysis is required to verify memory safety as long as only the safe
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instructions are used. The safe instruction set is expressive enough to
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implement WebAssembly.
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Scalable performance
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Cretonne can be configured to generate code as quickly as possible, or it
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can generate very good code at the cost of slower compile times.
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Predictable performance
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When optimizing, Cretonne focuses on adapting the target-independent IL to
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the quirks of the target architecture. There are no advanced optimizations
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that sometimes work, somtimes fail.
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Building the documentation
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--------------------------
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To build the Cretonne documentation, you need the `Sphinx documentation
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generator <http://www.sphinx-doc.org/>`_::
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$ pip install sphinx==1.3.5 sphinx-autobuild
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$ cd cretonne/docs
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$ make html
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$ open _build/html/index.html
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The specific Sphinx version is currently used by Read the Docs. Sphinx 1.4 has
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been released, but produces lots of warnings about four-column indices. We'll
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upgrade when Read the Docs does.
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