+ /// addPrefSpill - Add PrefSpill constraints to all blocks listed. This is
+ /// equivalent to calling addConstraint with identical BlockConstraints with
+ /// Entry = Exit = PrefSpill, and ChangesValue = false.
+ ///
+ /// @param Blocks Array of block numbers that prefer to spill in and out.
+ /// @param Strong When true, double the negative bias for these blocks.
+ void addPrefSpill(ArrayRef<unsigned> Blocks, bool Strong);
+