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Comment by SotCodeLaureate | Hacker News Reader

Recently I wrote a simplistic RISC-V interpreter for educational purposes mostly, and a friend was benchmarking it against several scripting system in the context of game-character control routines. Well, it's quite fast for what it is, though Lua is still somewhat faster, heh.

Some benchmarking code is here: https://github.com/glebnovodran/roam_bench

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Very cool! One tip: Take the execute segment and produce fast bytecodes instead of interpreting each instruction as a bit pattern. Producing faster bytecodes is something that even WASM emulators do, despite it being a bytecode format.

What’s the difference between a bit pattern and a bytecode?

The fast bytecode is reduced to a simple operation that excludes certain knowns. For example if you have an instruction that stores A0 = A1 + 0, then knowing the immediate is zero, this can be reduced from reading a complex bit pattern to a bytecode that moves from one register to another, basically MV dst=A0, src=A1.

So what would a bit pattern be in this case? I ask because I’m probably being too simple, but from a certain point of view, it’s all bits.

Thanks! Yeah, this one is supposed to be a very simple implementation for a kind of "how to write a machine code interpreter" tutorial, but I was looking to experiment with some optimizations if time permits. Patching with pre-baked alt-bytecode was one of the ideas indeed.

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