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Author: Afnan Attar

README.md

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+# APReF: Automatic Parallelizer of REcursive Functions
+
+This is a source-to-source Haskell compiler that automatically identifies and rewrites recursive functions in a parallel form.
+
+Optimizations implemented:
+* Automatic parallelization
+* Constant folding
+* Reassociation of terms for commutative operations
+* Symbolic simplification of scan operations
+
+### References
+
+[**Automatic Parallelization of Recursive Functions with Rewriting Rules**](https://doi.org/10.1016/j.scico.2018.01.004)  
+Rodrigo C. O. Rocha, Luís F. W. Góes, Fernando M. Q. Pereira  
+Journal of Science of Computer Programming, 2018
+
+[An Algebraic Framework for Parallelizing Recurrence in Functional Programming](http://dx.doi.org/10.1007/978-3-319-45279-1_10)  
+Rodrigo C. O. Rocha, Luís F. W. Góes, Fernando M. Q. Pereira  
+SBLP 2016 - Brazilian Symposium on Programming Languages
+
+
+### Example
+
+Given the following sequential recursive function:
+```
+f :: Integer -> [Integer]
+f 0 = []
+f n = [n] ++ f(n-1) ++ [n]
+```
+the source-to-source compiler is able to rewrite it as in the following parallel version:
+```
+f_g_1 :: Integer -> [Integer]
+f_g_1 i = [i]
+f_g_2 :: Integer -> [Integer]
+f_g_2 i = [i]
+f :: Integer -> [Integer]
+f 0 = []
+f n = let k = n
+      in (parFoldr (++) (map f_g_1 (reverse [1..k]))) ++ [] ++
+         (parFoldr (++) (map f_g_2 [1..k]))
+```
+
+### Usage
+
+By passing a Haskell file to the source-to-source compiler,
+any parallelizable function will be rewritten in their parallel counterparts.
+Auxiliary packages and functions will also be added.
+
+```
+python apref.py -f <haskell-file> --scan --constfold
+```
+
+The flag '--scan' enables a scan-based optimization.
+Similarly, the '--constfold' enables a constant folding optimization.
+
+"# APReF-using-python3"