MIPS Missing Instructions for R3000A

[Jaguar83]

After doing a simple test with some invalid instructions found in a program I'm reverse engineering, I've found some instructions that binutils recognises that capstone doesn't. I'm working on a Playstation 1 binary, so they may be exclusive to the PSX. I've provided the assembler file I used to test, commented with the output of objdump's -d.

testasm.txt

[kevinhartman]

@Jaguar83 I can confirm these are missing (I know your original post was years ago :) ). They're defined in the MIPS I ISA and should be added to Capstone. According to your testasm.txt, PS1 must have some custom hardware mapped to co-processor 2.

Adding a list here so we can document what's missing.

Missing in Capstone

cop0
cop1
cop2
cop3
cfc2
cfc3

# the following can all also be achieved using the cop0 instruction, but they also have their own mnemonic short-hands.
rfe
tlbp
tlbr
tlbwi
tlbwr

Others may be missing as well.

[kabeor]

Close this issue for now because of legacy, we are preparing to release Capstone 5.0, plz feel free to open a new issue if that still has this issue. thx :)

[tnias]

I learned about the rfe instruction today and tested with the current 5.0-rc2 candidate. It is not there yet.

$ cstool -v
cstool for Capstone Disassembler, v5.0.0
Capstone build: x86=1 arm=1 arm64=1 mips=1 ppc=1 sparc=1 sysz=1 xcore=1 m68k=1 tms320c64x=1 m680x=1 evm=1 wasm=1 mos65xx=1 bpf=1 riscv=1
$ cstool mipsbe 0x42000018
 0  42 00 00 18  eret
$ cstool mipsbe 0x42000010
ERROR: invalid assembly code

btw. ghidra has support https://github.com/NationalSecurityAgency/ghidra/issues/1764