Optimal simulation speed and synthesizability are contradictory requirements for a hardware description language. This paper presents a language and toolset that enables both synthesis and fast simulation of fixed-point signal processing algorithms at the register-transfer level using a single system description. This is achieved by separate code generators for different purposes. Code-generators have been developed for fast simulation (using ANSI-C) and for synthesis (using VHDL). The simulation performance of the proposed approach has been compared with other known methods and turns out to be comparable in speed to the fastest among them