[Mesa-dev] [PATCH 2/3] glsl: add continue/break/return unification/elimination pass

[Luca Barbieri]

I added two commits that allow unrolling of loops with jumps.

One fixes a serious bug in loop controls, where the analyzer wouldn't
recognize the from/to/increment data it itself created on a previous
run.

The second adds code to build the if structures to the unroller.

Note that some orderings of ir_lower_jumps and loop_analyze may still
cause problems if ir_lower_jumps manages to hide the loop variable
from loop_analyze.
It might be best to run loop_analyze first for now until we are sure it works.