A microprogrammed interpreter for concurrent euclid

Abstract

There are several methods of executing programs written in a high level language. The most widely used is to compile the programs into machine language. Another is to translate the programs into some intermediate form and then to execute that form interpretively. A third method is to directly execute either the HLL or the intermediate form. This study was aimed at investigating the feasibility of directly executing the intermediate representation of the sequential features of Concurrent Euclid (CE) on the SEL 32/75 computer. The CE intermediate code was translated into Ecode, and a microprogrammed interpreter for Ecode was designed and implemented on the SEL, and benchmarked against the compiler. For the CPU-bound prime number algorithm Sieve of Eratosthenes, the interpreter was measured to be about twice as slow as the compiler, due primarily to poor overlap within microinstructions. Ecode was then modified, and a new translator and interpreter designed and implemented. The same benchmark then yielded comparable results for both the interpreter and compiler. We project that further changes in Ecode design and hardware support would result in substantial Ecode efficiency gains.