PS2Recomp: PlayStation 2 Static Recompiler (Not ready)

• Note this is an experiment and does work as it should, feel free to open a PR to help the project.

PS2Recomp is a tool designed to statically recompile PlayStation 2 ELF binaries into C++ code that can be compiled for any modern platform. This enables running PS2 games natively on PC and other platforms without traditional emulation.

Features

• Translates MIPS R5900 instructions to C++ code
• Supports PS2-specific 128-bit MMI instructions
• Handles VU0 in macro mode
• Supports relocations and overlays
• Configurable via TOML files
• Single-file or multi-file output options
• Function stubbing and skipping

How It Works

PS2Recomp works by:

Parsing a PS2 ELF file to extract functions, symbols, and relocations Decoding the MIPS R5900 instructions in each function Translating those instructions to equivalent C++ code Generating a runtime that can execute the recompiled code

The translated code is very literal, with each MIPS instruction mapping to a C++ operation. For example, addiu $r4, $r4, 0x20 becomes ctx->r4 = ADD32(ctx->r4, 0X20);.

Requirements

• CMake 3.20 or higher
• C++20 compatible compiler (I only test with MSVC)
• SSE4/AVX support for 128-bit operations

Building

git clone --recurse-submodules https://github.com/ran-j/PS2Recomp.git
cd PS2Recomp

# Create build directory
mkdir build
cd build

cmake ..
cmake --build .

Usage

1. Create a configuration file (see ./ps2xRecomp/example_config.toml)
2. Run the recompiler:

./ps2recomp your_config.toml

Compile the generated C++ code Link with a runtime implementation

Configuration

PS2Recomp uses TOML configuration files to specify:

• Input ELF file
• Output directory
• Functions to stub or skip
• Instruction patches

Example configuration:

[general]
input = "path/to/game.elf"
output = "output/"
single_file_output = false

# Functions to stub
stubs = ["printf", "malloc", "free"]

# Functions to skip
skip = ["abort", "exit"]

# Patches
[patches]
instructions = [
  { address = "0x100004", value = "0x00000000" }
]

Runtime

To execute the recompiled code, you'll need to implement or use a runtime that provides:

• Memory management
• System call handling
• PS2-specific hardware simulation

A basic runtime header is provided in ps2xRuntime folder.

Limitations

• VU1 microcode support is limited
• Graphics Synthesizer and other hardware components need external implementation
• Some PS2-specific features may not be fully supported yet

Acknowledgments

• Inspired by N64Recomp
• Uses ELFIO for ELF parsing
• Uses toml11 for TOML parsing
• Uses fmt for string formatting