1 research outputs found
Linear Tree Constraints
Linear tree constraints were introduced by Hofmann and Rodriguez in the
context of amortized resource analysis for object oriented programs. More
precisely, they gave a reduction from inference of resource types to constraint
solving. Thus, once we have found an algorithm to solve the constraints
generated from a program, we can read off the resource consumption from their
solutions.
These constraints have the form of pointwise linear inequalities between
infinite trees labeled with nonnegative rational numbers. We are interested in
the question if a system of such constraints is simultaneously satisfiable.
Bauer and Hofmann have recently identified a fragment of the tree constraint
problem (UTC) that is still sufficient for program analysis and they proved
that the list case of UTC is decidable, whereas the case with trees of degree
at least two remained open. In this paper, we solve this problem. We give a
decision procedure that covers the entire range of constraints needed for
resource analysis