ppc750cl

Rust tools for working with the PowerPC 750CL family of processors.

Rust crates

rustup components add rustfmt
cargo run --package ppc750cl-genisa
cargo build --release

Python module

python -m venv env
source ./env/bin/activate
pip install maturin
maturin build -m ./disasm-py/Cargo.toml

Install module in dev env

maturin develop -m ./disasm-py/Cargo.toml
python
>>> import ppc750cl
>>> ins = ppc750cl.Ins(addr=0x80006969, code=0x10400420)
>>> str(ins)
'ps_merge00 f2, f0, f0'
>>> ins.fields()
[('frD', 2), ('frA', 0), ('frB', 0)]
>>> ins.frD
2

Instruction Set

For those unfamiliar with PowerPC, here are some basics.

• PowerPC 7xx is a family of RISC CPUs produced from 1997 to 2012.
  • They operate with 32-bit words and every instruction is 32-bits wide.
• This project focuses (only) on compatibility with the PowerPC 750CL.
  • This chip is famously packaged as codename "Broadway" for the Nintendo Wii.
  • Its predecessor PowerPC 750CXe is used in the Nintendo GameCube.
  • It adds a "paired-singles" SIMD unit and a bunch of other instructions.

isa.yaml

The file isa.yaml contains a full definition of the PowerPC 750CL instruction set.

It powers the disassembler, assembler, and Rust/Python bindings code analysis tools.

Similarly to LLVM TableGen, the program ppc750cl-genisa generates a Rust file implementing an instruction decoder.

Safety & Correctness

• This project does not use unsafe Rust code outside of testing utils.
• The disassembler has been fuzzed over all ~4.29 billion possible instructions (via ppc750cl-fuzz).
• It is safe to run the disassembler over untrusted byte arrays.
• However no guarantees on correctness are made (yet). Expect bugs.

Performance

• Performance isn't great but acceptable.
• Disassembling & printing: 600k insn/s (2.4 MB/s)
• Disassembling only: 6M insn/s (24 MB/s)