An investigation of static versus dynamic scheduling

Two techniques for instruction scheduling, dynamic and static scheduling, are investigated. A decoupled access execute architecture consists of an execution unit and a memory unit with separate program counters and separate instruction memories. The very long instruction word (VLIW) architecture has only one program counter and relies on the compiler to perform static scheduling of multiple units. To idealize the comparison, the VLIW architecture considered had only two units. The instruction sets and execution times for the two architectures were made as nearly the same as possible. The execution times were compared and analyzed to compare the capabilities of static and dynamic instruction scheduling. Both regular and irregular programs were constructed and optimized by hand for each architecture