PyPy's approach to virtual machine construction

ABSTRACT

The PyPy project seeks to prove both on a research and a practical level the feasibility of constructing a virtual machine (VM) for a dynamic language in a dynamic language - in this case, Python. The aim is to translate (i.e. compile) the VM to arbitrary target environments, ranging in level from C/Posix to Smalltalk/Squeak via Java and CLI/.NET, while still being of reasonable efficiency within these environments.A key tool to achieve this goal is the systematic reuse of the Python language as a system programming language at various levels of our architecture and translation process. For each level, we design a corresponding type system and apply a generic type inference engine - for example, the garbage collector is written in a style that manipulates simulated pointer and address objects, and when translated to C these operations become C-level pointer and address instructions.

References

1. B. Alpern, C. R. Attanasio, J. J. Barton, M. G. Burke, P. Cheng, J.-D. Choi, A. Cocchi, S. J. Fink, D. Grove, M. Hind, S. F. Hummel, D. Lieber, V. Litvinov, M. F. Mergen, T. Ngo, J. R. Russell, V. Sarkar, M. J. Serrano, J. C. Shepherd, S. E. Smith, V. C. Sreedhar, H. Srinivasan, and J. Whaley. The Jalapeno virtual machine. IBM Systems Journal, 39(1):211--, 2000.
2. C. S. Ananian. The static single information form. Master's thesis, Massachusetts Institute of Technology, September 1999.
3. M. Arnold, S. Fink, D. Grove, M. Hind, and P. F. Sweeney. Architecture and policy for adaptive optimization in virtual machines. Technical Report 23429, IBM Research, November 2004.
4. AT&T. Graphviz - graph visualization software. http://www.graphviz.org/.
5. S. M. Blackburn, P. Cheng, and K. S. McKinley. Oil and Water? High Performance Garbage Collection in Java with MMTk. In ICSE, pages 137--146, 2004.
6. H. Boehm. A garbage collector for C and C++. http://www.hpl.hp.com/personal/Hans_Boehm/gc/.
7. H.-J. Boehm and M. Weiser. Garbage collection in an uncooperative environment. Softw. Pract. Exper., 18(9):807--820, 1988.
8. G. Bracha. Pluggable type systems. In OOPSLA04 Workshop on Revival of Dynamic Languages, October 2004.
9. R. Cytron, J. Ferrante, B. K. Rosen, M. N. Wegman, and F. K. Zadeck. Efficiently computing static single assignment form and the control dependence graph. ACM Transactions on Programming Languages and Systems, 13(4):451--490, October 1991.
10. L. Damas and R. Milner. Principal type-schemes for functional programs. In POPL '82: Proceedings of the 9th ACM SIGPLAN-SIGACT symposium on Principles of programming languages, pages 207--212, New York, NY, USA, 1982. ACM Press.
11. D. Ingalls, T. Kaehler, J. Maloney, S. Wallace, and A. Kay. Back to the future: the story of Squeak, a practical Smalltalk written in itself. In OOPSLA '97: Proceedings of the 12th ACM SIGPLAN conference on Object-oriented programming, systems, languages, and applications, pages 318--326, New York, NY, USA, 1997. ACM Press.
12. N. Jones, C. Gomard, and P. Sestoft. Partial Evaluation and Automatic Program Generation. P-H, 1993.
13. R. Kelsey. Pre-scheme: A scheme dialect for systems programming.
14. C. Lattner and V. Adve. LLVM: A Compilation Framework for Lifelong Program Analysis & Transformation. In Proceedings of the 2004 International Symposium on Code Generation and Optimization (CGO'04), Palo Alto, California, Mar 2004.
15. R. Milner. A theory of type polymorphism in programming. J. Comput. Syst. Sci., 17(3):348--375, 1978.
16. PyPy Team. PyPy - Architecture Overview. Web page. http://codespeak.net/pypy/dist/pypy/doc/archi-tecture.html.
17. PyPy Team. PyPy - Translation. Web page, in-progress. http://codespeak.net/pypy/dist/pypy/doc/trans-lation.html.
18. PyPy Team. Complete python implementation running on top of cpython. Technical report, PyPy Consortium, 2005. http://codespeak.net/svn/pypy/extradoc/eu-report/.
19. A. Rigo. Representation-based just-in-time specialization and the psyco prototype for python. In PEPM '04: Proceedings of the 2004 ACM SIGPLAN symposium on Partial evaluation and semantics-based program manipulation, pages 15--26, New York, NY, USA, 2004. ACM Press.
20. A. Rigo, M. Hudson, and S. Pedroni. Compiling dynamic language implementations. Technical report, PyPy Consortium, 2005. http://codespeak.net/svn/pypy/extradoc/eu-report/.
21. D. Ungar, A. Spitz, and A. Ausch. Constructing a metacircular virtual machine in an exploratory programming environment. In OOPSLA '05: Companion to the 20th annual ACM SIGPLAN conference on Object-oriented programming, systems, languages, and applications, pages 11--20, New York, NY, USA, 2005. ACM Press.
22. G. van Rossum et al. CPython 2.4.3, March 2006. http://www.python.org/download/releases/2.4.3/.
23. T. Wang and S. F. Smith. Precise constraint-based type inference for java. In ECOOP '01: Proceedings of the 15th European Conference on Object-Oriented Programming, pages 99--117, London, UK, 2001. Springer-Verlag.
24. R. P. Weicker. Dhrystone benchmark: rationale for version 2 and measurement rules. SIGPLAN Not., 23(8):49--62, 1988.

Index Terms

• Software and its engineering

  • Software notations and tools

    • Compilers

      • Interpreters

      • Runtime environments

      • Source code generation

• Theory of computation

  • Semantics and reasoning

    • Program reasoning

      • Program analysis

    • Program semantics