An effective out-of-order execution control scheme for an embedded floating point coprocessor

This paper proposes an out-of-order execution control scheme that can be effectively applied to a coprocessor for embedded systems. A floating-point coprocessor has generally multiple pipelines such as a floating-point adder, a floating-point multiplier, a floating-point divider and a load/store pipelines. In order to utilize fully these pipelines, a constraint-based dynamic control scheme is designed for a coprocessor. This control scheme can be achieved by a data dependency checking, a resource conflict checking, and an exception prediction technique. With this control scheme a coprocessor can execute its instructions out of order without an extra hardware unit for out-of-order execution control.