Just got my HiFive1 up and running, and I've already played around with some blink Arduino sketches and the programs that come with the Freedom E SDK.
I've run the Dhrystone example program, and this is what I'm getting:
core freq at 269418496 Hz
Dhrystone Benchmark, Version 2.1 (Language: C)
Microseconds for one run through Dhrystone: 1314.6
Dhrystones per Second: 760.6
This is extraordinarily slow. I checked this again with a Dhrystone Arduino sketch, and I'm getting better results: 38412.07 Dhrystones per second for the SiFive 1 with the 256 MHz PLL. Still, this isn't good
Just for comparison, a 16MHz Arduino Micro runs about 18000 Dhrystones per second.
Obviously, the SiFive can do better, but what's the solution? Is this a compiler optimization error, or is this deeper into the toolchain?