A method for area estimation of data-path in high level synthesis

This paper describes a new method to estimate the area of data paths generated during a High Level Synthesis (HLS) process, when the information concerning the circuit is not yet complete. Our method is more accurate and considers more factors than those used by other HLS systems of which we are aware. Our main concern is the interconnection area, often neglected by HLS systems, which has a strong influence on the final circuit area being optimized, as well as a high dependency on the technology used and on the circuit area itself. Predicting the area of a design layout with accuracy is important because it allows one to foresee whether the design will satisfy the area constraints, and will lend the allocator towards the best design among several possibilities with guarantees. Our estimations of the final standard-cell layout area are similar, or even more accurate, than those obtained following methods used by low-level design systems, which have much more information available. Due to the performance penalty their relatively high complexity will produce, these methods are unusable in an HLS system exploring a wide design space. Our estimation, on the contrary, has a low complexity and can be repeated time and again as the HLS design space is searched.