Checker performance

KAST checkers that use a combination of ascendant/descendant (or parent/child) specifiers in a single KAST expression dramatically slow analysis speed.

The ascendant node triggers the "climb" up to the root of the AST, trying to find all definitions for a given name, while the descendant node triggers a full traversal of the subtree.

For fast analysis results, it's best to avoid using combination of ascendant/descendant or parent/child combinations.