The paper gives three compiler supports for Partial Predication: <1>. Predicate Promotion, <2>.
Basic Conversions <3>. Peephole Optimizations. The Predicate promotion requires the destinations
of the partial predication to be temporary registers. How often is this situation true for a typical program?
For the basic conversion, it requires the instructions are non-excepting. Since these techniques are valid
under very limited situations, it's not clear to what extent they help improved the performance.