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 (http://llvm.org/) 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 (http://clang.llvm.org/), and many other associated tools.
For more information, see: https://www.alcf.anl.gov/user-guides/bgclang-compiler
Hal Finkel, email@example.com
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]