MPI Reduction Analyzer

This tool statically analyzes LLVM IR code to identify opportunities for MPI reduction operations like MPI_Reduce, MPI_Allreduce, etc. It detects manual reduction patterns in C/C++ programs and suggests optimization potential for collective communication.

Project Structure

MPIReduction/
├── build/ # Build directory (CMake output + binary)
│ └── mpi_reduction_analyzer
├── include/ # Header files
│ ├── MPIReductionAnalyzer.h
│ ├── MPIReductionPass.h
│ ├── ReductionDetector.h
│ └── Utils.h
├── src/ # Source files (main logic)
│ ├── main.cpp
│ ├── MPIReductionAnalyzer.cpp
│ ├── MPIReductionPass.cpp
│ ├── ReductionDetector.cpp
│ └── Utils.cpp
├── test/ # Test files
│ ├── mpi.h
│ ├── test_reduction.ll # LLVM IR for testing
│ ├── testit.c # Optional C file to generate IR
│ └── testit.ll
├── CMakeLists.txt # CMake configuration
├── build.md # (Optional) Build documentation
└── README.md # 📄 You're reading it!

Prerequisites

• LLVM (v10 or higher) with clang, opt, and llvm-config
• CMake ≥ 3.10
• C++ compiler (g++ or clang++)
• Unix-like environment (Linux, WSL, macOS)

LLVM + Clang + Build Tools Setup on Ubuntu

Update package list

sudo apt update

Install compiler toolchain, CMake, and Ninja

sudo apt install -y build-essential cmake ninja-build

Install LLVM core tools and Clang

sudo apt install -y clang llvm lld

Install development libraries for writing LLVM passes

sudo apt install -y llvm-dev libclang-dev clang-tools

Install OpenMPI and mpicc

sudo apt install -y openmpi-bin libopenmpi-dev

Check Installed Versions

clang --version
llvm-as --version
cmake --version
ninja --version

Build Instructions

1. Clone the repo or navigate into the folder

cd MPIReduction

2. Create a build directory

mkdir build && cd build

3. Generate Makefiles using CMake

cmake ..

4. Compile the analyzer

make

This produces the binary: ./build/mpi_reduction_analyzer

Generate Intermediate Code

clang -S -emit-llvm test/testit.c -o test/testit.ll

Usage

/path/to/mpi_reduction_analyzer -analyze-mpi-reduction= /path/to/input.ll