Package: numba-rvsdg
numba-rvsdgNumba compatible RVSDG (Regionalized Value State Dependence Graph)  utilities.aboutThis repository contains Numba compatible utilities for working with RVSDGs
(Regionalized Value State Dependency Graphs). RVSDGs are a type of
Intermediary Representation (IR) suitable for regularizing Python bytecode
within Numba.The code in this repository is an implementation of the CFG restructuring
algorithms in Bahmann 2015, specifically those from section 4.1 and 4.2: namely
"loop restructuring" and "branch restructuring". These are interesting for
Numba because they serve to clearly identify regions within the Python
bytecode.dependenciesPython 3.11graphvizpyyamlYou can create a conda env using the following:conda env create -n numba-rvsdg python=3.11 python-graphviz
conda activate numba-rvsdg
pip install pyyamlAt the time of writingpyyamlwas not available for Python 3.11 viadefaultsso it had to be installed withpip.overviewThe following files are included in this repository:numba_rvsdg
├── __init__.py
├── core
│   ├── datastructures
│   │   ├── basic_block.py  # BasicBlock implementation
│   │   ├── scfg.py         # SCFG implementation, maps names to blocks
│   │   ├── byte_flow.py    # ByteFlow implementation, SCFG + bytecode
│   │   ├── flow_info.py    # Converts program to ByteFlow
│   ├── transformations.py  # Algorithms
│   └── utils.py            # Miscellaneous utilities
├── networkx_vendored
│   └── scc.py              # Strongly Connected Componets (loop detection)
├── rendering
│   └── rendering.py        # Graphivz based rendering of SCFGs
├── tests
│   ├── simulator.py        # Simulator utility for running SCFGs
│   ├── test_byteflow.py    # Testung ByteFlow and others
│   ├── test_fig3.py        # Testing fig. 3 from Bahman2015
│   ├── test_fig4.py        # Testing fig. 4 from Bahman2015
│   ├── test_simulate.py    # Simulator based testing
│   └── test_transforms.py  # Testing graph transformations
└── utilsexampleThe following will process the given example function and display the four
different stages. "initial" is the unprocessed bytecode as produced by
cpython. "closed" is simply the closed variant of the initial CFG. "loop
restructuring" is the loop-restructured version and "branch-restructured" is
the final form which includes closing, loop-restructuring and
branch-restructuring.# Example: for loop with branch and early exitfromnumba_rvsdg.rendering.renderingimportrender_funcdeffoo(n):c=0foriinrange(n):c+=1ifi==100:breakreturncrender_func(foo)referencesReismann2020--https://arxiv.org/pdf/1912.05036.pdf-- Describes the concept of RVSDGsBahmann2015--https://dl.acm.org/doi/pdf/10.1145/2693261-- Describes the transformation
algorithms implementedlicenseCopyright (c) 2022, Anaconda, Inc.
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