[Mesa-dev] r300 compiler scheduler fixes

[Tom Stellard]

This patch and also
http://lists.freedesktop.org/archives/mesa-dev/2010-July/001252.html
should fix all the outstanding scheduler bugs.

This patch adds a register rename pass that converts the code into quasi-SSA
form, which makes it easier for the scheduler to schedule TEX blocks.
This fixes: https://bugs.freedesktop.org/show_bug.cgi?id=28606

If there are no major objections to these, I'll push them to master.

-Tom