Destination-Driven Code Generation

Destination-driven code generation is a simple top-down technique that allows the code generated for a program phrase to depend upon its context in an abstract syntax tree. The context is encapsulated in a data destination and a control destination. The data destination specifies where the value computed by an expression is to be stored, while the control destination specifies where program execution is to resume after computation of the value. Together, the destinations allow a code generator to specify data and control flow dependencies between subcomputations. As a result, these subcomputations can be “wired” together in an efficient manner. We illustrate the technique by presenting a code generator for a subset of the programming language C. This technique has been used in the implementation of an incremental compiler for the Scheme programming language that generates code for one of several computer architectures.