Friday, January 27, 2006

Shed Skin 0.0.6

Here goes 0.0.6.. :)

With the help of Bearophile, I optimized list comprehensions and iteration a bit further. Programs are now also compiled together with the builtins, which can greatly improve performance in some cases. For example, the Pythonchess speed test engine now becomes about 22 times faster on my computer. Please check it out, and let me know about any problems you encounter.

For 0.0.7, I am working on a 'char' type. That is, let the compiler use the C++ 'char' type whenever programs are working with strings of length one. This dramatically improves the speed of programs that use strings of length 1 and/or 'string[index]' a lot. If you'd like to try it out, keep a watch on CVS, because I will commit this change soon, and let me know about any problems.

Saturday, January 14, 2006

0.0.6 Update

Hello there,

Just to let anyone interested know that SS development is alive and kicking; expect me to release 0.0.6 within about a week! Unfortunately, I did not find the time to work on a connection with arbitrary external libraries. There have been many small improvements, though, relative to I also added two new largish programs:

-a stripped-down version of Pythonchess, thanks to Jyrki, the author! (360 lines)
-yet another sudoku solver, that would cause older versions of SS to choke badly (178 lines)

The former becomes about 9 times faster on my PC, but there are probably some simple optimizations I can do to improve this further. The latter really gave the type inferencer a hard time, so I added some simple heuristics to 'guess' types, for use as a starting point of the analysis. This greatly reduced the analysis time for many other tests.

Btw, the raytracer is 65 times faster on my PC at home (X2 4800+), instead of the 40 I measured in China :-)

Shed Skin now correctly compiles about 6000 lines of unit tests. Included in these are the following non-trivial programs:

-satisfiability solver 1
-satisfiability solver 2
-min/max othello player
-neural network simulator
-sudoku solver 1
-sudoku solver 2
-sudoku solver 3
-convex hull
-the pygmy raytracer
-tic-tac-toe on arbitrary-size boards
-linear algebra routines
-simple genetic algorithm
-conway game of life
-pythonchess speed test engine

I'm starting to become pretty confident the compiler will work well in general. The speedups are also pretty good in general, but I think it can be much improved still, by tweaking code generation and the C++ versions of the Python builtins. I could really use a hand here! :D

(update: Anyone would like to try and get SS to run using, say, vc++?)