Dynamically scheduling the trace produced during program execution into VLIW instructions

VLIW machines possibly provide the most direct way to exploit instruction level parallelism; however, they cannot be used to emulate current general-purpose instruction set architectures. Programs scheduled for a particular implementation of a VLIW model cannot be guaranteed to be binary compatible with other implementations of the same machine model with different number of functional-units. This paper describes an architecture, named dynamically trace scheduled VLIW (DTSVLIW), which can be used to implement machines that execute code of current RISC or CISC instruction set architectures in a VLIW fashion, with backward code compatibility. Some preliminary performance measurements of the DTSVLIW, obtained with an execution-driven simulator running the SPECint95 benchmark suite, are also presented.