Currently i want to evaluate different RISCV open source ISA simulators. Ex: Spike and Quemu. and i want to choose one of them for my work. My goal is to run a small program on this ISA simulator and later i want to add a new custom instruction to the existing RISC-V ISA and accelerate some crypto operations like Ex shift, rotate. Finally i want to see what is the acceleration i am getting with this customization.
There are many RISC-V ISA simulators available. Which is the best one that i should choose ?
spike and qemu are the two main ones though. Generally qemu is more useful to software developers because it is faster. spike is more useful to hardware developers because it provides better traces. Spike is also easier to modify which may be relevant to you.
The proposed B extension has rotate instructions. The Imperas simulator has B support. I don’t know if any of the others do. See github.com/riscv/riscv-bitmanip
Spike and qemu are functional ISA simulator, if you want to get the precise acceleration , you should try some cycle-accurate simulator, like firesim, gem5…