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ppc750cl
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ppc750cl/README.md

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ppc750cl

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

Building

cargo run --package ppc750cl-genisa
cargo build --release

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 and assembler.

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

With a single thread on Ryzen 9 3900X:

  • Disassembling & printing: ~5M insn/s (~20 MB/s)
  • Disassembling only: ~50M insn/s (~200 MB/s)