bgclang Compiler

bgclang, a compiler toolchain based on the LLVM/Clang compiler infrastructure, but customized for the IBM Blue Gene/Q (BG/Q) supercomputer, is a successful experiment in creating an alternative, high-quality compiler toolchain for non-commodity HPC hardware. By enhancing LLVM ( with support for the BG/Q's QPX vector instruction set, bgclang inherits from LLVM/Clang a high-quality auto-vectorizing optimizer, C++11 frontend (, and many other associated tools.

For more information, see:

Primary Contact: 

Hal Finkel,


Hal Finkel, "bgclang: Creating an Alternative, Customizable, Toolchain for the Blue Gene/Q." IEEE/ACM International Conference for High Performance Computing, Networking, Storage, and Analysis, November 16 - 21, 2014. [Poster]