+ /// spilled. This vector is retained.
+ void prepare(BitVector &RegBundles);
+
+ /// addConstraints - Add constraints and biases. This method may be called
+ /// more than once to accumulate constraints.
+ /// @param LiveBlocks Constraints for blocks that have the variable live in or
+ /// live out.
+ void addConstraints(ArrayRef<BlockConstraint> LiveBlocks);
+
+ /// 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);
+
+ /// addLinks - Add transparent blocks with the given numbers.
+ void addLinks(ArrayRef<unsigned> Links);
+
+ /// scanActiveBundles - Perform an initial scan of all bundles activated by
+ /// addConstraints and addLinks, updating their state. Add all the bundles
+ /// that now prefer a register to RecentPositive.
+ /// Prepare internal data structures for iterate.
+ /// Return true is there are any positive nodes.
+ bool scanActiveBundles();
+
+ /// iterate - Update the network iteratively until convergence, or new bundles
+ /// are found.
+ void iterate();
+
+ /// getRecentPositive - Return an array of bundles that became positive during
+ /// the previous call to scanActiveBundles or iterate.
+ ArrayRef<unsigned> getRecentPositive() { return RecentPositive; }
+
+ /// finish - Compute the optimal spill code placement given the
+ /// constraints. No MustSpill constraints will be violated, and the smallest
+ /// possible number of PrefX constraints will be violated, weighted by
+ /// expected execution frequencies.
+ /// The selected bundles are returned in the bitvector passed to prepare().