Control Flow Aspects of Semantics-Directed Compiling

This paper is a demonstration of a semantics-directed compiler generator. We focus on the part of a compiler between syntax analysis and code generation. A language is specified by adding semantic rules in a functional notation to the syntax of the language. Starting with a small sublanguage of while statements, statement constructs of the C programming language are added in stages. Using a small ad hoc code generator, a compiler is automatically constructed from the semantics. The semantic description is analogous to a syntax-directed construction of a flow diagram for a program. By analogy with grammars and parser generators, minimal knowledge of the underlying theory is required. For the control flow aspects of languages, efficient compilers can quickly be generated.