Optimization as Transformations: A Compiler Paradigm

This thesis describes the high-level transformation phase of a prototype PSL compiler. EPIC The transformations are separated into two classes: machine dependent code generation, and machine independent code optimization. The code generation phase transforms an intermediate representation of a program into a form that is easy to translate into object code. The optimizing transformations use the results of the generation transformations, along with predefined knowledge of machine independent optimization, to improve the efficiency of the tailored code. A facility for specifying machine dependent optimization also exists. The entire transformation phase is viewed as two interrelated mechanisms operations on the code, which specify a syntactic transformation, and operations on attributes of various elements of the code, which specify semantic transformations. A method for the implementation of these mechanisms is investigated.