src/hotspot/share/opto/loopnode.hpp

@@ -41,10 +41,11 @@
  class Node;
  class OuterStripMinedLoopEndNode;
  class PredicateBlock;
  class PathFrequency;
  class PhaseIdealLoop;
+ class UnswitchCandidate;
  class UnswitchedLoopSelector;
  class VectorSet;
  class VSharedData;
  class Invariance;
  struct small_cache;

@@ -77,11 +78,12 @@
           HasAtomicPostLoop     = 1<<11,
           StripMined            = 1<<12,
           SubwordLoop           = 1<<13,
           ProfileTripFailed     = 1<<14,
           LoopNestInnerLoop     = 1<<15,
-          LoopNestLongOuterLoop = 1<<16 };
+          LoopNestLongOuterLoop = 1<<16,
+          FlatArrays            = 1<<17};
    char _unswitch_count;
    enum { _unswitch_max=3 };
  
    // Expected trip count from profile data
    float _profile_trip_cnt;

@@ -100,10 +102,11 @@
    bool is_strip_mined() const { return _loop_flags & StripMined; }
    bool is_profile_trip_failed() const { return _loop_flags & ProfileTripFailed; }
    bool is_subword_loop() const { return _loop_flags & SubwordLoop; }
    bool is_loop_nest_inner_loop() const { return _loop_flags & LoopNestInnerLoop; }
    bool is_loop_nest_outer_loop() const { return _loop_flags & LoopNestLongOuterLoop; }
+   bool is_flat_arrays() const { return _loop_flags & FlatArrays; }
  
    void mark_partial_peel_failed() { _loop_flags |= PartialPeelFailed; }
    void mark_was_slp() { _loop_flags |= WasSlpAnalyzed; }
    void mark_passed_slp() { _loop_flags |= PassedSlpAnalysis; }
    void mark_do_unroll_only() { _loop_flags |= DoUnrollOnly; }

@@ -113,10 +116,11 @@
    void clear_strip_mined() { _loop_flags &= ~StripMined; }
    void mark_profile_trip_failed() { _loop_flags |= ProfileTripFailed; }
    void mark_subword_loop() { _loop_flags |= SubwordLoop; }
    void mark_loop_nest_inner_loop() { _loop_flags |= LoopNestInnerLoop; }
    void mark_loop_nest_outer_loop() { _loop_flags |= LoopNestLongOuterLoop; }
+   void mark_flat_arrays() { _loop_flags |= FlatArrays; }
  
    int unswitch_max() { return _unswitch_max; }
    int unswitch_count() { return _unswitch_count; }
  
    void set_unswitch_count(int val) {

@@ -688,10 +692,11 @@
    bool policy_peel_only( PhaseIdealLoop *phase ) const;
  
    // Return TRUE or FALSE if the loop should be unswitched -- clone
    // loop with an invariant test
    bool policy_unswitching( PhaseIdealLoop *phase ) const;
+   bool no_unswitch_candidate() const;
  
    // Micro-benchmark spamming.  Remove empty loops.
    bool do_remove_empty_loop( PhaseIdealLoop *phase );
  
    // Convert one iteration loop into normal code.

@@ -1424,25 +1429,27 @@
    // Clone loop with an invariant test (that does not exit) and
    // insert a clone of the test that selects which version to
    // execute.
    void do_unswitching(IdealLoopTree* loop, Node_List& old_new);
  
-   IfNode* find_unswitch_candidate(const IdealLoopTree* loop) const;
+   IfNode* find_unswitch_candidates(const IdealLoopTree* loop, Node_List& flat_array_checks) const;
+   IfNode* find_unswitch_candidate_from_idoms(const IdealLoopTree* loop) const;
  
   private:
    static bool has_control_dependencies_from_predicates(LoopNode* head);
    static void revert_to_normal_loop(const LoopNode* loop_head);
  
    void hoist_invariant_check_casts(const IdealLoopTree* loop, const Node_List& old_new,
-                                    const UnswitchedLoopSelector& unswitched_loop_selector);
+                                    const UnswitchCandidate& unswitch_candidate, const IfNode* loop_selector);
    void add_unswitched_loop_version_bodies_to_igvn(IdealLoopTree* loop, const Node_List& old_new);
    static void increment_unswitch_counts(LoopNode* original_head, LoopNode* new_head);
    void remove_unswitch_candidate_from_loops(const Node_List& old_new, const UnswitchedLoopSelector& unswitched_loop_selector);
  #ifndef PRODUCT
    static void trace_loop_unswitching_count(IdealLoopTree* loop, LoopNode* original_head);
    static void trace_loop_unswitching_impossible(const LoopNode* original_head);
    static void trace_loop_unswitching_result(const UnswitchedLoopSelector& unswitched_loop_selector,
+                                             const UnswitchCandidate& unswitch_candidate,
                                              const LoopNode* original_head, const LoopNode* new_head);
  #endif
  
   public:
  

@@ -1573,11 +1580,13 @@
    bool split_up( Node *n, Node *blk1, Node *blk2 );
  
    Node* place_outside_loop(Node* useblock, IdealLoopTree* loop) const;
    Node* try_move_store_before_loop(Node* n, Node *n_ctrl);
    void try_move_store_after_loop(Node* n);
+   void move_flat_array_check_out_of_loop(Node* n);
    bool identical_backtoback_ifs(Node *n);
+   bool flat_array_element_type_check(Node *n);
    bool can_split_if(Node *n_ctrl);
    bool cannot_split_division(const Node* n, const Node* region) const;
    static bool is_divisor_loop_phi(const Node* divisor, const Node* loop);
    bool loop_phi_backedge_type_contains_zero(const Node* phi_divisor, const Type* zero) const;
  

@@ -1782,10 +1791,12 @@
    void update_addp_chain_base(Node* x, Node* old_base, Node* new_base);
  
    bool can_move_to_inner_loop(Node* n, LoopNode* n_loop, Node* x);
  
    void pin_array_access_nodes_dependent_on(Node* ctrl);
+ 
+   void collect_flat_array_checks(const IdealLoopTree* loop, Node_List& flat_array_checks) const;
  };
  
  
  class AutoNodeBudget : public StackObj
  {