The implementation of an out-of-order execution floating point unit

The prRISC32 FPU (floating-point unit) is a RISC coprocessor for embedded system applications. It supports IEEE754 standard single/double precision floating-point addition, floating-point subtraction, floating-point multiplication, floating-point division, floating-point square root, floating-point/fix-point format conversion, and floating point load/store, etc. It also supports four IEEE compliant rounding mode, and precise exception. It can execute and complete instructions out of order under certain cases. Commercial 0.18μm 1P6M standard cell library was used to reduce design time and expense. The prototype chip was operated at about 300 MHz and with the worst-case operating conditions can be operated at about 250MHz in post-route simulation.