The FPU in the 29050 was based on the Am29325 bit-slice family FPU; an extra write port was added to the register file to allow for asynchronous FPU result writ

The FPU in the 29050 was based on the Am29325 bit-slice family FPU; an extra write port was added to the register file to allow for asynchronous FPU result writeback, which allowed the parallel operation. gr2 and gr3 were used in the 29050 for FP condition code registers, but otherwise I'm pretty sure accessing the rest caused a trap.