[Mesa-dev] glsl: soft fp64 precursor patches

[Dave Airlie]

I've been fixing up Elie's work and although the produced shaders are large,
and really show up the copy prop and sb liveness passes as horrible inefficent
when you have lots of if statements, I think we should start angling towards
upstreaming it.

It now passes 99% of the piglit tests on r600 with nosb, so I think the glsl
code is pretty much working.

These 6 patches are the patches to the current 64-bit lowering code to
give it the ability to handle doubles. None of these should break anything
currently.

Dave.