Graal IR: An Extensible Declarative Intermediate Representation

We present an intermediate representation (IR) for a Java just in time (JIT) compiler written in Java. It is a graph-based IR that models both control-flow and data-flow dependencies between nodes. We show the framework in which we devel-oped our IR. Much care has been taken to allow the pro-grammer to focus on compiler optimization rather than IR bookkeeping. Edges between nodes are declared concisely using Java annotations, and common properties and func-tions on nodes are communicated to the framework by im-plementing interfaces. Building upon these declarations, the graph framework automatically implements a set of useful primitives that the programmer can use to implement opti-mizations