Open64 has been well-recognized as an industrial-strength production compiler. It is the final result of research contributions from a number of compiler groups around the world. Formerly known as Pro64, Open64 was initially created by SGI from SGI's MIPSPro compiler, and licensed under the GNU Public License (GPL v2).
Open64 includes advanced interprocedural optimizations, loop nest optimizations, global scalar optimizations, and code generation with advanced global register allocation and software pipelining.
See the official website: Open64