Beyond working on initial Ivy Bridge support
and continuing to fortify the Sandy Bridge support
, Intel's OSTC team is still working on improving the GLSL compiler for Mesa.
Intel's improved GL Shading Language compiler has been living in Mesa master for nearly one year
and is used by all Mesa / Gallium3D drivers, but it's still not yet perfect and still there are a variety of areas to improve. One of the features that's been missing in the Mesa GLSL compiler up to this point is support for use-define chains, but now that's finally coming.
Ian Romanick has published his Mesa ud-chains branch that provides this support to clear up some ugly hacks within Mesa's core code-base. For those interested in more technical details about this ud-chains work for Mesa's GLSL compiler, see Ian's blog post
Right now the code is living in a separate branch, but hopefully it will end up being yet another feature for Mesa 7.11.