Nios II, floating point hardware.

Hi @PShar32 ,

If you're using C++, then you can just ignore the assembler code. The performance table in this link https://www.intel.com/content/www/us/en/docs/programmable/683836/current/multiply-and-divide-performance-83984.html also applicable to C++ arithmetic operators.

As for performance, the Nios II/f will be the fastest among the Nios II. Can check the Arithmetic Instructions tab (image):

The best performance for Multiply Extended (64-bit double precision) is 1 cycle if set Multiply Implementation: 1 32-bit multiplier.

Based on the link above,

However, if an instruction depends on the result of an earlier instruction, then the processor stalls through any result latency cycles until the result is ready.

If there is dependency between the results and operands for back-to-back instructions, there will be extra 2 Result Latency Cycles. In that case, that'll be a total of 3 cycles (1 cycle + 2 cycles).

Thanks,

Best regards,

Sheng

p/s: If any answer from the community or Intel Support are helpful, please feel free to give best answer or rate 4/5 survey.