#MRSC
MRSC is a toolkit for rapid design and prototyping of (multi-result) supercompilers. MRSC 1.0 provides generic data structures and operations for building supercompilers based on the concept of graph of configurations. A supercompiler is encoded as a set of graph rewrite rules.
##Papers
The theory behind MRSC is described in the following papers:
- Ilya Klyuchnikov and Sergei Romanenko. Multi-Result Supercompilation as Branching Growth of the Penultimate Level in Metasystem Transitions. Ershov Informatics Conference 2011. pdf (Revised version is in LNCS 7162, pp. 210–226, 2012)
- Ilya Klyuchnikov and Sergei Romanenko. MRSC: a toolkit for building multi-result supercompilers. Preprint 77. Keldysh Institute of Applied Mathematics, Moscow. 2011. pdf
##Code structure
MRSC is divided in a number of packages:
mrsc.core- Generic data structures (
SGraphandTGraph) for representing a graph of configurations and operations on them. - An abstraction
GraphRewriteRulesfor encoding the logic of supercompilation in terms of rewriting rules. - The component
GraphGeneratorfor incremental producing all possible graphs of configurations for a given set of rewriting rules.
- Generic data structures (
mrsc.counters- Example of a very simple (but non-trivial!) supercompiler for counter systems (see below).
##Example: generating proofs of safety of cache-coherence protocols
The entry point to this example is mrsc/counters/demo.scala (just launch it to see results in the console).
The package mrsc.counters contains an example of building a traditional (single-result) supercompiler and a (novel)
multi-result supercompiler for counter systems. This example is inspired by works by Andrei Nemytykh, Alexei Lisitsa
and Andrei Klimov:
- A. Lisitsa and A. Nemytykh. Verification as a parameterized testing (experiments with the SCP4 supercompiler). Programming and Computer Software. vol. 33. 2007
- Andrei V. Klimov, A Java Supercompiler and its Application to Verification of Cache-Coherence Protocols. In: Perspectives of Systems Informatics: 7th International Andrei Ershov Memorial Conference, PSI 2009, Novosibirsk, Russia, June 15-19, 2009. Revised Papers. Lecture Notes in Computer Science, volume 5947/2010, pages 185-192. Springer Berlin / Heidelberg, 2010.
- Andrei V. Klimov, Solving Coverability Problem for Monotonic Counter Systems by Supercompilation. In: E.M. Clarke, I. Virbitskaite, A. Voronkov (eds.), Proceedings of the Ershov Informatics Conference (PSI 2011), June 17 – July 01, 2011, Akademgorodok, Novosibirsk, Russia. Novosibirsk: Ershov Institute of Informatics Systems, 2011. P. 92-103.
- SCP 4 : Verification of Protocols
- The project JVer
The works [1, 2, 4, 5] use the following approach for verification of protocols: express a protocol and its safety
property as a Java of Refal program, supercompile a boolean expression stating the safety property of protocol -
from the structure of supercompiled expression it will follow the safety of protocol. Following [3], we
created a tiny language (of configurations) for encoding states of protocols (mrsc/counters/language.scala).
Then protocols are expressed in Scala directly - as a DSL over the language of configurations
(mrsc/counters/protocols.scala). There are two supercompilers in mrsc/counters/rules.scala encoded as graph
rewrite rules - traditional single-result one and multi-result one. These supercompilers build graphs of
configurations for a given protocol. Using a graph of configurations, we are able to produce a proof
of safety of a protocol for a proof assistant Isabelle
(mrsc/counters/proof.scala). Demo application in mrsc/counters/demo.scala puts all things together:
for a number of protocols traditional supercompiler is launched (as in [3]), multi-result supercompiler is launched and
the smallest graphs is then selected from a set of graphs generated by multi-result supercompiler.
The smallest graph is then residuated into a proof for Isabelle. More details are in an upcoming paper.
The output of demo is shown in proofs.md.