Computing Just Right: Accuracy Specification and Error Analysis

This chapter first defines the accuracy of an operator with respect to the operation it is supposed to implement, discussing in particular various approaches to the notion of rounding. It then states that for efficient application-specific arithmetic, operators should be accurate to their last bit. To reach this objective, it sketches a generic methodology: the error analysis of parametric designs, which can then be exploited to investigate (in an application-specific way) which parameter values lead to best accurate design. This generic methodology is also shown to be well suited to the hierarchical design of complex computing cores assembled out of simpler ones and will be used throughout the book.