Original Article

Acta Informatica

, Volume 44, Issue 2, pp 75-90

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Decision problems for pushdown threads

  • Jan A. BergstraAffiliated withFaculty of Science, Programming Research Group, University of AmsterdamUtrecht University, Department of Philosophy, Applied Logic Group
  • , Inge BethkeAffiliated withFaculty of Science, Programming Research Group, University of Amsterdam
  • , Alban PonseAffiliated withFaculty of Science, Programming Research Group, University of Amsterdam Email author 

Abstract

Threads as contained in a thread algebra emerge from the behavioral abstraction from programs in an appropriate program algebra. Threads may make use of services such as stacks, and a thread using a single stack is called a pushdown thread. Equivalence of pushdown threads is shown decidable whereas pushdown thread inclusion is undecidable. This is again an example of a borderline crossing where the equivalence problem is decidable, whereas the inclusion problem is not.