1 /*
  2  * Copyright (c) 2015, 2017, 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_ZBARRIER_HPP
 25 #define SHARE_GC_Z_ZBARRIER_HPP
 26 
 27 #include "memory/allocation.hpp"
 28 #include "oops/oop.hpp"
 29 
 30 typedef bool (*ZBarrierFastPath)(uintptr_t);
 31 typedef uintptr_t (*ZBarrierSlowPath)(uintptr_t);
 32 
 33 class ZBarrier : public AllStatic {
 34 private:
 35   static const bool Follow      = true;
 36   static const bool DontFollow  = false;
 37 
 38   static const bool Strong      = false;
 39   static const bool Finalizable = true;
 40 
 41   static const bool Publish     = true;
 42   static const bool Overflow    = false;
 43 
 44   template <ZBarrierFastPath fast_path, ZBarrierSlowPath slow_path> static oop barrier(volatile oop* p, oop o);
 45   template <ZBarrierFastPath fast_path, ZBarrierSlowPath slow_path> static oop weak_barrier(volatile oop* p, oop o);
 46   template <ZBarrierFastPath fast_path, ZBarrierSlowPath slow_path> static void root_barrier(oop* p, oop o);
 47 
 48   static bool is_null_fast_path(uintptr_t addr);
 49   static bool is_good_or_null_fast_path(uintptr_t addr);
 50   static bool is_weak_good_or_null_fast_path(uintptr_t addr);
 51 
 52   static bool during_mark();
 53   static bool during_relocate();
 54   template <bool finalizable> static bool should_mark_through(uintptr_t addr);
 55   template <bool follow, bool finalizable, bool publish> static uintptr_t mark(uintptr_t addr);
 56   static uintptr_t remap(uintptr_t addr);
 57   static uintptr_t relocate(uintptr_t addr);
 58   static uintptr_t relocate_or_mark(uintptr_t addr);
 59   static uintptr_t relocate_or_remap(uintptr_t addr);
 60 
 61   static uintptr_t load_barrier_on_oop_slow_path(uintptr_t addr);
 62 
 63   static uintptr_t weak_load_barrier_on_oop_slow_path(uintptr_t addr);
 64   static uintptr_t weak_load_barrier_on_weak_oop_slow_path(uintptr_t addr);
 65   static uintptr_t weak_load_barrier_on_phantom_oop_slow_path(uintptr_t addr);
 66 
 67   static uintptr_t keep_alive_barrier_on_weak_oop_slow_path(uintptr_t addr);
 68   static uintptr_t keep_alive_barrier_on_phantom_oop_slow_path(uintptr_t addr);
 69 
 70   static uintptr_t mark_barrier_on_oop_slow_path(uintptr_t addr);
 71   static uintptr_t mark_barrier_on_finalizable_oop_slow_path(uintptr_t addr);
 72   static uintptr_t mark_barrier_on_root_oop_slow_path(uintptr_t addr);
 73   static uintptr_t mark_barrier_on_invisible_root_oop_slow_path(uintptr_t addr);
 74 
 75   static uintptr_t relocate_barrier_on_root_oop_slow_path(uintptr_t addr);
 76 
 77 public:
 78   // Load barrier
 79   static  oop load_barrier_on_oop(oop o);
 80   static  oop load_barrier_on_oop_field(volatile oop* p);
 81   static  oop load_barrier_on_oop_field_preloaded(volatile oop* p, oop o);
 82   static void load_barrier_on_oop_array(volatile oop* p, size_t length);
 83   static void load_barrier_on_oop_fields(oop o);
 84   static  oop load_barrier_on_weak_oop_field_preloaded(volatile oop* p, oop o);
 85   static  oop load_barrier_on_phantom_oop_field_preloaded(volatile oop* p, oop o);
 86   static void load_barrier_on_root_oop_field(oop* p);
 87 
 88   // Weak load barrier
 89   static oop weak_load_barrier_on_oop_field(volatile oop* p);
 90   static oop weak_load_barrier_on_oop_field_preloaded(volatile oop* p, oop o);
 91   static oop weak_load_barrier_on_weak_oop(oop o);
 92   static oop weak_load_barrier_on_weak_oop_field(volatile oop* p);
 93   static oop weak_load_barrier_on_weak_oop_field_preloaded(volatile oop* p, oop o);
 94   static oop weak_load_barrier_on_phantom_oop(oop o);
 95   static oop weak_load_barrier_on_phantom_oop_field(volatile oop* p);
 96   static oop weak_load_barrier_on_phantom_oop_field_preloaded(volatile oop* p, oop o);
 97 
 98   // Is alive barrier
 99   static bool is_alive_barrier_on_weak_oop(oop o);
100   static bool is_alive_barrier_on_phantom_oop(oop o);
101 
102   // Keep alive barrier
103   static void keep_alive_barrier_on_weak_oop_field(volatile oop* p);
104   static void keep_alive_barrier_on_phantom_oop_field(volatile oop* p);
105   static void keep_alive_barrier_on_phantom_root_oop_field(oop* p);
106 
107   // Mark barrier
108   static void mark_barrier_on_oop_field(volatile oop* p, bool finalizable);
109   static void mark_barrier_on_oop_array(volatile oop* p, size_t length, bool finalizable);
110   static void mark_barrier_on_root_oop_field(oop* p);
111   static void mark_barrier_on_invisible_root_oop_field(oop* p);
112 
113   // Relocate barrier
114   static void relocate_barrier_on_root_oop_field(oop* p);
115 
116   // Narrow oop variants, never used.
117   static oop  load_barrier_on_oop_field(volatile narrowOop* p);
118   static oop  load_barrier_on_oop_field_preloaded(volatile narrowOop* p, oop o);
119   static void load_barrier_on_oop_array(volatile narrowOop* p, size_t length);
120   static oop  load_barrier_on_weak_oop_field_preloaded(volatile narrowOop* p, oop o);
121   static oop  load_barrier_on_phantom_oop_field_preloaded(volatile narrowOop* p, oop o);
122   static oop  weak_load_barrier_on_oop_field_preloaded(volatile narrowOop* p, oop o);
123   static oop  weak_load_barrier_on_weak_oop_field_preloaded(volatile narrowOop* p, oop o);
124   static oop  weak_load_barrier_on_phantom_oop_field_preloaded(volatile narrowOop* p, oop o);
125 };
126 
127 #endif // SHARE_GC_Z_ZBARRIER_HPP