395T Topics in Theorem Proving: ACL2

Schedule Details

Fall, 2000


``ACL2'' stands for ``A Computational Logic for Applicative Common Lisp.'' It is a functional programming language, a mathematical logic and a mechanical theorem prover for that logic. ACL2 is used to model computing systems -- both hardware and software -- and to prove properties of those models. The ACL2 home page is http://www.cs.utexas.edu/users/moore/acl2. ACL2 is used primarily in industry to prove properties of microprocessors. For example, the IEEE compliance of the RTL implementing the elementary floating-point operations on the AMD Athlon (TM) microprocessor was proved by David Russinoff using ACL2, and ACL2 was used at Rockwell-Collins to model the JEM1 microprocessor, the world's first silicon Java Virtual Machine. These and many other applications are described in http://www.cs.utexas.edu/users/moore/publications/acl2-papers.html.

In this class you will learn how to use ACL2. The class will start with an introduction to Lisp and to ACL2. You will then be given elementary exercises to do with ACL2 and we will gradually build up to more elaborate examples such as the modelling of simple programming languages, compilers, and architectures.

You will be expected to use ACL2 to do the assignments. ACL2 is freely available on the net (see the ACL2 home page). ACL2 can be installed on top of any Common Lisp. ACL2 is installed under the departmental Unix/Linux machines under /p/bin/acl2. Extensive hypertext documentation is available.

As a side-effect of the course, I hope to develop a FAQ for ACL2 for new users.

PhD dissertation topics in this area include new theorem proving techniques, new and effective models of computational systems (especially parallel and distributed systems), effective embeddings or connections to other formal systems such as model checking, Unity and TLA, proof management tools, and interface and visualization tools.


The ideal prerequisite is to have taken CS389R (Recursion and Induction). Alternatively, knowledge of Common Lisp and familiarity with mathematical logic is very helpful. However, the course is open to any graduate student.


Computer-Aided Reasoning: An Approach, Kaufmann, Manolios, and Moore, Kluwer, 2000.

Tests and Grades

Grades will be based on class participation.