src/hotspot/share/opto/predicates_enums.hpp

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#ifndef SHARE_OPTO_PREDICATES_ENUMS_HPP
#define SHARE_OPTO_PREDICATES_ENUMS_HPP

// The success projection of a Parse Predicate is always an IfTrueNode and the uncommon projection an IfFalseNode
typedef IfTrueNode ParsePredicateSuccessProj;
typedef IfFalseNode ParsePredicateUncommonProj;

// Assertion Predicates are either emitted to check the initial value of a range check in the first iteration or the last
// value of a range check in the last iteration of a loop.
enum class AssertionPredicateType {
  None, // Not an Assertion Predicate
  InitValue,
  LastValue,
  // Used for the Initialized Assertion Predicate emitted during Range Check Elimination for the final IV value.
  FinalIv
};

enum class PredicateState {
  // The Predicate is useless and will be cleaned up in the next round of IGVN. A useless Predicate is not visited
  // anymore by PredicateVisitors. If a Predicate loses its connection to a loop head, it will be marked useless by
  // EliminateUselessPredicates and cleaned up by the Value() methods of the associated Predicate IR nodes.
  Useless,
  // This state is used by EliminateUselessPredicates to temporarily mark a Predicate as neither useless nor useful.
  // Outside EliminateUselessPredicates, a Predicate should never be MaybeUseful.
  MaybeUseful,
  // Default state: The Predicate is useful and will be visited by PredicateVisitors.
  Useful
};

#endif // SHARE_OPTO_PREDICATES_ENUMS_HPP