System level fixed-point design based on an interpolative approach

ABSTRACT

The design process for fixed-point implementations eitherin software or in hardware requires a bit-true specificationof the algorithm in order to analyze quantization effectson an algorithmical level, abstracting from implementationaldetails.On the other hand, system design starts froma floating-point description into a fixed-point description becomesnecessary.Within this paper we present a tool thatallows an automated, interactive transformation from floating-pointANSI-C into a bit-true specification based ona new data type fixed that is introduced as an extensionto ANSI-C.The concept is rooted in a sophisticated datadependency analysis that allows to handle control structuresas well as pointers.It is part of the fixed-point designenvironment FRIDGE which includes an advanced simulatorthat covers the extended ANSI-C syntax as well astarget specific compilers which allow to generate efficientfixed-point implementations either for HW or for SW, startingfrom the bit-true algorithm specification.

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INDEX TERMS

Primary Classification:
  G. Mathematics of Computing
  G.1 NUMERICAL ANALYSIS

Additional Classification:
  B. Hardware
  B.5 REGISTER-TRANSFER-LEVEL IMPLEMENTATION

  C. Computer Systems Organization

General Terms:
Design, Performance, Theory