Phoronix: Assembly Shader Rework Hitting Mesa Today

Intel's Ian Romanick began last year working on a new GLSL compiler for Mesa, but those plans were abandoned due to a lack of time and the overwhelming challenge. Instead, Ian began focusing on optimizing the IR (Intermediate Representation) used by Mesa in its OpenGL support and then generating the final machine code. Ian has been working in a branch of Mesa with what he calls the "Assembly Shader Rework" and rewriting the ARB program parser and adding in support for NVIDIA layered extensions...

http://www.phoronix.com/vr.php?view=NzQ2OQ