1 /*
   2  * Copyright (c) 2015, 2019, 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 #ifndef SHARE_GC_Z_C2_ZBARRIERSETC2_HPP
  25 #define SHARE_GC_Z_C2_ZBARRIERSETC2_HPP
  26 
  27 #include "gc/shared/c2/barrierSetC2.hpp"
  28 #include "memory/allocation.hpp"
  29 #include "opto/node.hpp"
  30 #include "utilities/growableArray.hpp"
  31 
  32 const uint8_t ZLoadBarrierStrong = 1;
  33 const uint8_t ZLoadBarrierWeak   = 2;
  34 const uint8_t ZLoadBarrierElided = 3;
  35 
  36 class ZLoadBarrierStubC2 : public ResourceObj {
  37 private:
  38   const MachNode* _node;
  39   const Address   _ref_addr;
  40   const Register  _ref;
  41   const Register  _tmp;
  42   const bool      _weak;
  43   Label           _entry;
  44   Label           _continuation;
  45 
  46   ZLoadBarrierStubC2(const MachNode* node, Address ref_addr, Register ref, Register tmp, bool weak);
  47 
  48 public:
  49   static ZLoadBarrierStubC2* create(const MachNode* node, Address ref_addr, Register ref, Register tmp, bool weak);
  50 
  51   Address ref_addr() const;
  52   Register ref() const;
  53   Register tmp() const;
  54   address slow_path() const;
  55   RegMask& live() const;
  56   Label* entry();
  57   Label* continuation();
  58 };
  59 
  60 class ZBarrierSetC2 : public BarrierSetC2 {
  61 private:
  62   void compute_liveness_at_stubs() const;
  63   void analyze_dominating_barriers() const;
  64 
  65 protected:
  66   virtual Node* load_at_resolved(C2Access& access, const Type* val_type) const;
  67   virtual Node* atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access,
  68                                                Node* expected_val,
  69                                                Node* new_val,
  70                                                const Type* val_type) const;
  71   virtual Node* atomic_cmpxchg_bool_at_resolved(C2AtomicParseAccess& access,
  72                                                 Node* expected_val,
  73                                                 Node* new_val,
  74                                                 const Type* value_type) const;
  75   virtual Node* atomic_xchg_at_resolved(C2AtomicParseAccess& access,
  76                                         Node* new_val,
  77                                         const Type* val_type) const;
  78 
  79 public:
  80   virtual void* create_barrier_state(Arena* comp_arena) const;
  81   virtual bool array_copy_requires_gc_barriers(bool tightly_coupled_alloc,
  82                                                BasicType type,
  83                                                bool is_clone,
  84                                                ArrayCopyPhase phase) const;
  85 
  86   virtual void late_barrier_analysis() const;
  87   virtual size_t estimate_stub_size() const;
  88   virtual void emit_stubs(CodeBuffer& cb) const;
  89 };
  90 
  91 #endif // SHARE_GC_Z_C2_ZBARRIERSETC2_HPP