Allegrex instructions list

[frabert]

Hi everyone!

I'm searching for a list of the extra instructions the Allegrex processor in the PSP has in addition to a standard MIPS processor. Does anyone have something like that, or at least a way to extrapolate one?

[Henrik]

Just go look in the PPSSPP source code The GCC port for Allegrex also should have a list in it.

Most of the extra instructions are the VFPU ones. There are few additional once like shift-rotate.

[frabert]

Thanks for the quick reply, Henrik

Am I correct in my understanding that the code that would be relevant to me is in the Core/MIPS/ subdirectory of the repo?

[Henrik]

Yes. You can find the lookup table that is used to decode instructions in MIPSTables.cpp. Maybe start here: https://github.com/hrydgard/ppsspp/blob/...es.cpp#L99