Assessing the Impact of a Source Level Optimization Utility for Embedded Systems

Embedded software is different in many aspects to traditional software; as such, a software developer may face issues when attempting to transition from traditional to embedded software development. This thesis explores providing feedback and applying optimizations at the source code level of embedded software. The aim is to measure the impact of these optimizations on teaching embedded software design principles, as well as assessing the relative success of each optimization in terms of a variety of metrics. There are many considerations when altering code and is a known limitation imposed by most software optimization schemes. By applying optimizations at the source level, the aim is to demonstrate what the optimizations do and how they provide value to the resulting software. In order to fulfill these goals, the Embedded C Source Optimizer has been developed, which is used to import and export code, select which optimizations are applied, and provide feedback to the end user. This utility abstracts away the lower level operations performed by each optimization, while conveying the resulting changes to the end user. Since embedded systems are generally quite limited compared to modern computers, someone transitioning from traditional software design to embedded software may find it challenging to understand how to overcome these limitations. Clearly conveying means to improve a naive implementation of an embedded program aids through demonstrating what changes need to be made to satisfy embedded design rules. The optimizations which the utility can apply range from simple replacement operations to more complex applications of implicit utilization of built-in hardware peripherals on supported microcontrollers. Each optimization comes with its own set of considerations, risks, and potential level of improvement to the resulting code. These optimization options are evaluated by comparing embedded software before and after each option is applied through a variety of metrics, allowing the relative success of each to be determined as effectively as possible. The end goal for this utility is to aid in crossing the hurdle from traditional software to embedded software in a comprehensive and educational manner, with the provided optimization options acting as an avenue for teaching embedded concepts.