/*

 * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#ifndef SHARE_GC_Z_C2_ZBARRIERSETC2_HPP

#define SHARE_GC_Z_C2_ZBARRIERSETC2_HPP

#include "gc/shared/c2/barrierSetC2.hpp"

#include "memory/allocation.hpp"

#include "opto/node.hpp"

#include "utilities/growableArray.hpp"

class LoadBarrierNode : public MultiNode {

private:

  bool _weak;

  bool _writeback;          // Controls if the barrier writes the healed oop back to memory

                            // A swap on a memory location must never write back the healed oop

  bool _oop_reload_allowed; // Controls if the barrier are allowed to reload the oop from memory

                            // before healing, otherwise both the oop and the address must be

                            // passed to the barrier from the oop

  static bool is_dominator(PhaseIdealLoop* phase, bool linear_only, Node *d, Node *n);

  void push_dominated_barriers(PhaseIterGVN* igvn) const;

public:

  enum {

    Control,

    Memory,

    Oop,

    Address,

    Number_of_Outputs = Address,

    Similar,

    Number_of_Inputs

  };

  LoadBarrierNode(Compile* C,

                  Node* c,

                  Node* mem,

                  Node* val,

                  Node* adr,

                  bool weak,

                  bool writeback,

                  bool oop_reload_allowed);

  virtual int Opcode() const;

  virtual const Type *bottom_type() const;

  virtual const Type *Value(PhaseGVN *phase) const;

  virtual Node *Identity(PhaseGVN *phase);

  virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);

  LoadBarrierNode* has_dominating_barrier(PhaseIdealLoop* phase,

                                          bool linear_only,

                                          bool look_for_similar);

  void fix_similar_in_uses(PhaseIterGVN* igvn);

  bool has_true_uses() const;

  bool can_be_eliminated() const {

    return !in(Similar)->is_top();

  }

  bool is_weak() const {

    return _weak;

  }

  bool is_writeback() const {

    return _writeback;

  }

  bool oop_reload_allowed() const {

    return _oop_reload_allowed;

  }

};

class LoadBarrierSlowRegNode : public LoadPNode {

public:

  LoadBarrierSlowRegNode(Node *c,

                         Node *mem,

                         Node *adr,

                         const TypePtr *at,

                         const TypePtr* t,

                         MemOrd mo,

                         ControlDependency control_dependency = DependsOnlyOnTest)

  virtual const char * name() {

    return "LoadBarrierSlowRegNode";

  }

  virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {

    return NULL;

  }

  virtual int Opcode() const;

};

class LoadBarrierWeakSlowRegNode : public LoadPNode {

public:

  LoadBarrierWeakSlowRegNode(Node *c,

                             Node *mem,

                             Node *adr,

                             const TypePtr *at,

                             const TypePtr* t,

                             MemOrd mo,

                             ControlDependency control_dependency = DependsOnlyOnTest)

  virtual const char * name() {

    return "LoadBarrierWeakSlowRegNode";

  }

  virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {

    return NULL;

  }

  virtual int Opcode() const;

};

class ZBarrierSetC2State : public ResourceObj {

private:

  // List of load barrier nodes which need to be expanded before matching

  GrowableArray<LoadBarrierNode*>* _load_barrier_nodes;

public:

  ZBarrierSetC2State(Arena* comp_arena);

  int load_barrier_count() const;

  void add_load_barrier_node(LoadBarrierNode* n);

  void remove_load_barrier_node(LoadBarrierNode* n);

  LoadBarrierNode* load_barrier_node(int idx) const;

};

class ZBarrierSetC2 : public BarrierSetC2 {

private:

  ZBarrierSetC2State* state() const;

  Node* make_cas_loadbarrier(C2AtomicAccess& access) const;

  Node* make_cmpx_loadbarrier(C2AtomicAccess& access) const;

  void expand_loadbarrier_basic(PhaseMacroExpand* phase, LoadBarrierNode *barrier) const;

  void expand_loadbarrier_node(PhaseMacroExpand* phase, LoadBarrierNode* barrier) const;

  void expand_loadbarrier_optimized(PhaseMacroExpand* phase, LoadBarrierNode *barrier) const;

  const TypeFunc* load_barrier_Type() const;

protected:

  virtual Node* load_at_resolved(C2Access& access, const Type* val_type) const;

  virtual Node* atomic_cmpxchg_val_at_resolved(C2AtomicAccess& access,

                                               Node* expected_val,

                                               Node* new_val,

                                               const Type* val_type) const;

  virtual Node* atomic_cmpxchg_bool_at_resolved(C2AtomicAccess& access,

                                                Node* expected_val,

                                                Node* new_val,

                                                const Type* value_type) const;

  virtual Node* atomic_xchg_at_resolved(C2AtomicAccess& access,

                                        Node* new_val,

                                        const Type* val_type) const;

public:

  Node* load_barrier(GraphKit* kit,

                     Node* val,

                     Node* adr,

                     bool weak = false,

                     bool writeback = true,

                     bool oop_reload_allowed = true) const;

  virtual void* create_barrier_state(Arena* comp_arena) const;

  virtual bool is_gc_barrier_node(Node* node) const;

  virtual void eliminate_gc_barrier(PhaseMacroExpand* macro, Node* node) const { }

  virtual void eliminate_useless_gc_barriers(Unique_Node_List &useful) const;

  virtual void add_users_to_worklist(Unique_Node_List* worklist) const;

  virtual void enqueue_useful_gc_barrier(Unique_Node_List &worklist, Node* node) const;

  virtual void register_potential_barrier_node(Node* node) const;

  virtual void unregister_potential_barrier_node(Node* node) const;

  virtual bool array_copy_requires_gc_barriers(BasicType type) const { return true; }

  // If the BarrierSetC2 state has kept macro nodes in its compilation unit state to be

  // expanded later, then now is the time to do so.

  virtual bool expand_macro_nodes(PhaseMacroExpand* macro) const;

  static void find_dominating_barriers(PhaseIterGVN& igvn);

  static void loop_optimize_gc_barrier(PhaseIdealLoop* phase, Node* node, bool last_round);

#ifdef ASSERT

  virtual void verify_gc_barriers(bool post_parse) const;

#endif

};

#endif // SHARE_GC_Z_C2_ZBARRIERSETC2_HPP