/**
* This method returns the set of blocks that dominates the passed block, i.e., it answers the
* question "Who dominates me?"
*
* @param ir the governing IR
* @return a BitVector containing those blocks that dominate me
*/
BitVector dominators(IR ir) {
// Currently, this set is computed on demand,
// but we cache it for the next time.
if (dominators == null) {
dominators = new BitVector(ir.getMaxBasicBlockNumber() + 1);
dominators.set(block.getNumber());
DominatorTreeNode node = this;
while ((node = (DominatorTreeNode) getParent()) != null) {
dominators.set(node.getBlock().getNumber());
}
}
return dominators;
}
