Mechanistic Behavior of Single-Pass Instruction Sequences

TL;DR

This paper extends program algebra to include mechanistic processing, modeling unobservable delays such as jump instructions, and introduces a mechanistic improvement ordering for thread analysis.

Contribution

It introduces a novel mechanistic modeling approach for unobservable processing in instruction sequences and defines an improvement ordering for thread optimization.

Findings

Some threads lack an optimal implementation.

Mechanistic delays can be formally modeled using a delay operator.

The approach enhances understanding of unobservable program behaviors.

Abstract

Earlier work on program and thread algebra detailed the functional, observable behavior of programs under execution. In this article we add the modeling of unobservable, mechanistic processing, in particular processing due to jump instructions. We model mechanistic processing preceding some further behavior as a delay of that behavior; we borrow a unary delay operator from discrete time process algebra. We define a mechanistic improvement ordering on threads and observe that some threads do not have an optimal implementation.