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Luke Street
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Before, the mnemonic arrays would be generated on the stack at runtime in each parse function. This ensures that the arrays themselves are treated as const data.
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
unsafeRust 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)