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Guidelines to write fast code for PyPy's JIT
I was watching this talk at PyCon: http://pycon.tv/#/video/75
The speakers (the Pypy devs) mentioned that the Python language wasn't the problem with writing a speedy compiler so much as writing your code in a way that helps the JIT do its work quickly.
What are some techniques you can use to help a JIT compiler run quickly? The only one I can think of is that writing your code so it tends to follow the same path over and over again is an obvious help.