1 /*
  2  * Copyright (c) 2018, 2025, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  *
 23  */
 24 
 25 #ifndef SHARE_GC_G1_C2_G1BARRIERSETC2_HPP
 26 #define SHARE_GC_G1_C2_G1BARRIERSETC2_HPP
 27 
 28 #include "gc/shared/c2/cardTableBarrierSetC2.hpp"
 29 
 30 class PhaseTransform;
 31 class Type;
 32 class TypeFunc;
 33 
 34 const int G1C2BarrierPre         = 1;
 35 const int G1C2BarrierPost        = 2;
 36 const int G1C2BarrierPostNotNull = 4;
 37 
 38 class G1BarrierStubC2 : public BarrierStubC2 {
 39 public:
 40   static bool needs_pre_barrier(const MachNode* node);
 41   static bool needs_post_barrier(const MachNode* node);
 42   static bool post_new_val_may_be_null(const MachNode* node);
 43 
 44   G1BarrierStubC2(const MachNode* node);
 45   virtual void emit_code(MacroAssembler& masm) = 0;
 46 };
 47 
 48 class G1PreBarrierStubC2 : public G1BarrierStubC2 {
 49 private:
 50   Register _obj;
 51   Register _pre_val;
 52   Register _thread;
 53   Register _tmp1;
 54   Register _tmp2;
 55 
 56 protected:
 57   G1PreBarrierStubC2(const MachNode* node);
 58 
 59 public:
 60   static bool needs_barrier(const MachNode* node);
 61   static G1PreBarrierStubC2* create(const MachNode* node);
 62   void initialize_registers(Register obj, Register pre_val, Register thread, Register tmp1 = noreg, Register tmp2 = noreg);
 63   Register obj() const;
 64   Register pre_val() const;
 65   Register thread() const;
 66   Register tmp1() const;
 67   Register tmp2() const;
 68   virtual void emit_code(MacroAssembler& masm);
 69 };
 70 
 71 class G1BarrierSetC2: public CardTableBarrierSetC2 {
 72 private:
 73   void analyze_dominating_barriers() const;
 74 
 75 protected:
 76   bool g1_can_remove_pre_barrier(GraphKit* kit,
 77                                  PhaseValues* phase,
 78                                  Node* adr,
 79                                  BasicType bt,
 80                                  uint adr_idx) const;
 81 
 82   bool g1_can_remove_post_barrier(GraphKit* kit,
 83                                   PhaseValues* phase, Node* store,
 84                                   Node* adr) const;
 85 
 86   int get_store_barrier(C2Access& access) const;
 87 
 88   virtual Node* load_at_resolved(C2Access& access, const Type* val_type) const;
 89   virtual Node* store_at_resolved(C2Access& access, C2AccessValue& val) const;
 90   virtual Node* atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access, Node* expected_val,
 91                                                Node* new_val, const Type* value_type) const;
 92   virtual Node* atomic_cmpxchg_bool_at_resolved(C2AtomicParseAccess& access, Node* expected_val,
 93                                                 Node* new_val, const Type* value_type) const;
 94   virtual Node* atomic_xchg_at_resolved(C2AtomicParseAccess& access, Node* new_val, const Type* value_type) const;
 95 
 96 public:
 97   virtual void eliminate_gc_barrier(PhaseMacroExpand* macro, Node* node) const;
 98   virtual void eliminate_gc_barrier_data(Node* node) const;
 99   virtual bool expand_barriers(Compile* C, PhaseIterGVN& igvn) const;
100   virtual uint estimated_barrier_size(const Node* node) const;
101   virtual bool can_initialize_object(const StoreNode* store) const;
102   virtual void clone_at_expansion(PhaseMacroExpand* phase,
103                                   ArrayCopyNode* ac) const;
104   virtual void* create_barrier_state(Arena* comp_arena) const;
105   virtual void emit_stubs(CodeBuffer& cb) const;
106   virtual void elide_dominated_barrier(MachNode* mach) const;
107   virtual void late_barrier_analysis() const;
108 
109 #ifndef PRODUCT
110   virtual void dump_barrier_data(const MachNode* mach, outputStream* st) const;
111 #endif
112 };
113 
114 #endif // SHARE_GC_G1_C2_G1BARRIERSETC2_HPP