Table of Contents

• 1. License
• 2. Introduction
• 3. Prerequisites
• 4. Installation
  • 4.1. Building
• 5. Usage
  • 5.1. How to compile
    • 5.1.1. Single source
    • 5.1.2. Makefile
    • 5.1.3. Hybrid MPI-OpenMP programs
  • 5.2. Options
• 6. Logos

pooo#+TITLE: Archer

License

Please see LICENSE for usage terms.

Introduction

Archer is a data race detector for OpenMP programs.

Archer combines static and dynamic techniques to identify data races in large OpenMP applications, leading to low runtime and memory overheads, while still offering high accuracy and precision. It builds on open-source tools infrastructure such as LLVM and ThreadSanitizer to provide portability.

Prerequisites

To compile Archer you need an host GCC version >= 4.7.

Installation

Archer has been developed under LLVM 3.5 with OpenMP support (for more information go to http://clang-omp.github.io).

Building

First obtain Archer, e.g. from Github (https://github.com/soarlab/Archer):

git clone git@github.com:soarlab/Archer.git Archer

Then, build Archer by running install.sh:

./install.sh --prefix=llvm_install_path [default: --prefix=/usr]

The installation script will create a folder called LLVM at the same level of the Archer directory and install LLVM to llvm_install_path.

In case your GCC is not installed in a standard path you need to specify the GCC toolchain path for LLVM/Clang using the flag –gcc-toolchain-path:

./install.sh --prefix=llvm_install_path --gcc-toolchain-path=gcc_toolchain_path

Once the installation completes, you need to setup your environement to allow Archer to work correctly.

Please set the following path variables:

export PATH=${LLVM_INSTALL}/bin:${LLVM_INSTALL}/local/archer/bin:\${PATH}"
export LD_LIBRARY_PATH=${LLVM_INSTALL}/bin:${LLVM_INSTALL}/lib/intelomprt:${LLVM_INSTALL}/local/archer/lib:\${LD_LIBRARY_PATH}"

To make the environment permanent add the previous lines or equivalents to your shell start-up script such as "~/.bashrc".

WARNING:

During the installation process you may see an error like the following:

CMake Error: install(EXPORT "LLVMExports" ...) includes target "opt" which requires target "Polly" that is not in the export set.
CMake Error: install(EXPORT "LLVMExports" ...) includes target "bugpoint" which requires target "Polly" that is not in the export set.

It is an error related to the CMake configuration process of Polly. It does not affect your installation. Future versions of Archer will upgrade Polly to the latest version avoiding this problem.

Usage

How to compile

Archer provides a command to compile your programs with Clang/LLVM OpenMP and hide all the mechanics necessary to detect data races automatically in your OpenMP programs.

This Archer command is called clang-archer, and this can be used as a drop-in replacement of your compiler command (e.g., clang, gcc, etc.).

The following are some of the examples of how one can integrate clang-archer into his/her build system.

Single source

clang-archer example.c -L/path/to/openmp/runtime -lOMPRT -o example

Makefile

In your Makefile, set the following variables:

CC = clang-archer

LDFLAGS = -L/path/to/openmp/runtime -lOMPRT

Hybrid MPI-OpenMP programs

In your Makefile, set the following variables:

CC = mpicc -cc=clang-archer

...

LDFLAGS = -L/path/to/openmp/runtime -lOMPRT

Options

Running the following command:

clang-archer --help

shows the options available with clang-archer.

usage: clang-archer [-h] [-v] [-d] [--log] [-db] [-CC [CC]] [-USE_MPI]
                    [-MPICC [MPICC]] [-OPT [OPT]] [-LINK [LINK]] [-DIS [DIS]]
                    [-LIB [LIB]] [-PLUGIN_LIB [PLUGIN_LIB]]
                    [-OPENMP_INCLUDE [OPENMP_INCLUDE]] [-g]
                    [-O0 | -O1 | -O2 | -O3 | -Os | -Oz] [-fopenmp] [-liomp5]
                    [-c] [-o [O]]

Compile your program with Archer support, a data race detector for OpenMP programs.

optional arguments:
  -h, --help            show this help message and exit
  -v, --version         show program's version number and exit
  -d, --debug           Print the compiling commands
  --log                 Keep intermediate logs
  -db, --disable-blacklisting
                        Disable static analysis and apply ThreadSanitizer
                        instrumentation to the entire program
  -CC [CC]              Change the program used to compile and link the
                        programs
  -USE_MPI              Link against MPI libraries
  -MPICC [MPICC]        Change the program used to compile and link the MPI
                        programs
  -OPT [OPT]            Change the program used to optmize the programs
  -LINK [LINK]          Change the program used to link the byte code files
  -DIS [DIS]            Change the program used to disassemble the byte code
                        files
  -LIB [LIB]            Set the path where to find Archer libraries
  -PLUGIN_LIB [PLUGIN_LIB]
                        Set the path where to find Archer Plugin libraries
  -OPENMP_INCLUDE [OPENMP_INCLUDE]
                        Set the path where to find OpenMP headers
  -g                    If the debugging flag is not present in the
                        compilation command it will be added by default
  -O0                   The optimization flags will be forced to '-O0'
                        optimization level for analysis purposes
  -O1
  -O2
  -O3
  -Os
  -Oz
  -fopenmp              OpenMP flag
  -liomp5               OpenMP library
  -c                    Only run preprocess, compile, and assemble steps
  -o [O]                Output filename

Logos