1 /*
   2  * Copyright (c) 2015, 2018, 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_VM_OOPS_INSTANCEREFKLASS_INLINE_HPP
  26 #define SHARE_VM_OOPS_INSTANCEREFKLASS_INLINE_HPP
  27 
  28 #include "classfile/javaClasses.inline.hpp"
  29 #include "gc/shared/referenceProcessor.hpp"
  30 #include "logging/log.hpp"
  31 #include "oops/access.inline.hpp"
  32 #include "oops/compressedOops.inline.hpp"
  33 #include "oops/instanceKlass.inline.hpp"
  34 #include "oops/instanceRefKlass.hpp"
  35 #include "oops/oop.inline.hpp"
  36 #include "utilities/debug.hpp"
  37 #include "utilities/globalDefinitions.hpp"
  38 #include "utilities/macros.hpp"
  39 
  40 template <bool nv, typename T, class OopClosureType, class Contains>
  41 void InstanceRefKlass::do_referent(oop obj, OopClosureType* closure, Contains& contains) {
  42   T* referent_addr = (T*)java_lang_ref_Reference::referent_addr_raw(obj);
  43   if (contains(referent_addr)) {
  44     Devirtualizer<nv>::do_oop(closure, referent_addr);
  45   }
  46 }
  47 
  48 template <bool nv, typename T, class OopClosureType, class Contains>
  49 void InstanceRefKlass::do_next(oop obj, OopClosureType* closure, Contains& contains) {
  50   T* next_addr = (T*)java_lang_ref_Reference::next_addr_raw(obj);
  51   if (contains(next_addr)) {
  52     Devirtualizer<nv>::do_oop(closure, next_addr);
  53   }
  54 }
  55 
  56 template <bool nv, typename T, class OopClosureType, class Contains>
  57 void InstanceRefKlass::do_discovered(oop obj, OopClosureType* closure, Contains& contains) {
  58   T* discovered_addr = (T*)java_lang_ref_Reference::discovered_addr_raw(obj);
  59   if (contains(discovered_addr)) {
  60     Devirtualizer<nv>::do_oop(closure, discovered_addr);
  61   }
  62 }
  63 
  64 template <typename T, class OopClosureType>
  65 bool InstanceRefKlass::try_discover(oop obj, ReferenceType type, OopClosureType* closure) {
  66   ReferenceProcessor* rp = closure->ref_processor();
  67   if (rp != NULL) {
  68     T referent_oop = RawAccess<>::oop_load((T*)java_lang_ref_Reference::referent_addr_raw(obj));
  69     if (!CompressedOops::is_null(referent_oop)) {
  70       oop referent = CompressedOops::decode_not_null(referent_oop);
  71       if (!referent->is_gc_marked()) {
  72         // Only try to discover if not yet marked.
  73         return rp->discover_reference(obj, type);
  74       }
  75     }
  76   }
  77   return false;
  78 }
  79 
  80 template <bool nv, typename T, class OopClosureType, class Contains>
  81 void InstanceRefKlass::oop_oop_iterate_discovery(oop obj, ReferenceType type, OopClosureType* closure, Contains& contains) {
  82   // Try to discover reference and return if it succeeds.
  83   if (try_discover<T>(obj, type, closure)) {
  84     return;
  85   }
  86 
  87   // Treat referent as normal oop.
  88   do_referent<nv, T>(obj, closure, contains);
  89 
  90   // Treat discovered as normal oop, if ref is not "active" (next non-NULL).
  91   T next_oop  = RawAccess<>::oop_load((T*)java_lang_ref_Reference::next_addr_raw(obj));
  92   if (!CompressedOops::is_null(next_oop)) {
  93     do_discovered<nv, T>(obj, closure, contains);
  94   }
  95 
  96   // Treat next as normal oop.
  97   do_next<nv, T>(obj, closure, contains);
  98 }
  99 
 100 template <bool nv, typename T, class OopClosureType, class Contains>
 101 void InstanceRefKlass::oop_oop_iterate_fields(oop obj, OopClosureType* closure, Contains& contains) {
 102   do_referent<nv, T>(obj, closure, contains);
 103   do_discovered<nv, T>(obj, closure, contains);
 104   do_next<nv, T>(obj, closure, contains);
 105 }
 106 
 107 template <bool nv, typename T, class OopClosureType, class Contains>
 108 void InstanceRefKlass::oop_oop_iterate_discovered_and_discovery(oop obj, ReferenceType type, OopClosureType* closure, Contains& contains) {
 109   // Explicitly apply closure to the discovered field.
 110   do_discovered<nv, T>(obj, closure, contains);
 111   // Then do normal reference processing with discovery.
 112   oop_oop_iterate_discovery<nv, T>(obj, type, closure, contains);
 113 }
 114 
 115 template <bool nv, typename T, class OopClosureType, class Contains>
 116 void InstanceRefKlass::oop_oop_iterate_ref_processing_specialized(oop obj, OopClosureType* closure, Contains& contains) {
 117   switch (closure->reference_iteration_mode()) {
 118     case ExtendedOopClosure::DO_DISCOVERY:
 119       trace_reference_gc<T>("do_discovery", obj);
 120       oop_oop_iterate_discovery<nv, T>(obj, reference_type(), closure, contains);
 121       break;
 122     case ExtendedOopClosure::DO_DISCOVERED_AND_DISCOVERY:
 123       trace_reference_gc<T>("do_discovered_and_discovery", obj);
 124       oop_oop_iterate_discovered_and_discovery<nv, T>(obj, reference_type(), closure, contains);
 125       break;
 126     case ExtendedOopClosure::DO_FIELDS:
 127       trace_reference_gc<T>("do_fields", obj);
 128       oop_oop_iterate_fields<nv, T>(obj, closure, contains);
 129       break;
 130     default:
 131       ShouldNotReachHere();
 132   }
 133 }
 134 
 135 class AlwaysContains {
 136  public:
 137   template <typename T> bool operator()(T* p) const { return true; }
 138 };
 139 
 140 template <bool nv, class OopClosureType>
 141 void InstanceRefKlass::oop_oop_iterate_ref_processing(oop obj, OopClosureType* closure) {
 142   AlwaysContains always_contains;
 143   if (UseCompressedOops) {
 144     oop_oop_iterate_ref_processing_specialized<nv, narrowOop>(obj, closure, always_contains);
 145   } else {
 146     oop_oop_iterate_ref_processing_specialized<nv, oop>(obj, closure, always_contains);
 147   }
 148 }
 149 
 150 class MrContains {
 151   const MemRegion _mr;
 152  public:
 153   MrContains(MemRegion mr) : _mr(mr) {}
 154   template <typename T> bool operator()(T* p) const { return _mr.contains(p); }
 155 };
 156 
 157 template <bool nv, class OopClosureType>
 158 void InstanceRefKlass::oop_oop_iterate_ref_processing_bounded(oop obj, OopClosureType* closure, MemRegion mr) {
 159   const MrContains contains(mr);
 160   if (UseCompressedOops) {
 161     oop_oop_iterate_ref_processing_specialized<nv, narrowOop>(obj, closure, contains);
 162   } else {
 163     oop_oop_iterate_ref_processing_specialized<nv, oop>(obj, closure, contains);
 164   }
 165 }
 166 
 167 template <bool nv, class OopClosureType>
 168 void InstanceRefKlass::oop_oop_iterate(oop obj, OopClosureType* closure) {
 169   InstanceKlass::oop_oop_iterate<nv>(obj, closure);
 170 
 171   oop_oop_iterate_ref_processing<nv>(obj, closure);
 172 }
 173 
 174 #if INCLUDE_ALL_GCS
 175 template <bool nv, class OopClosureType>
 176 void InstanceRefKlass::oop_oop_iterate_reverse(oop obj, OopClosureType* closure) {
 177   InstanceKlass::oop_oop_iterate_reverse<nv>(obj, closure);
 178 
 179   oop_oop_iterate_ref_processing<nv>(obj, closure);
 180 }
 181 #endif // INCLUDE_ALL_GCS
 182 
 183 
 184 template <bool nv, class OopClosureType>
 185 void InstanceRefKlass::oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr) {
 186   InstanceKlass::oop_oop_iterate_bounded<nv>(obj, closure, mr);
 187 
 188   oop_oop_iterate_ref_processing_bounded<nv>(obj, closure, mr);
 189 }
 190 
 191 #ifdef ASSERT
 192 template <typename T>
 193 void InstanceRefKlass::trace_reference_gc(const char *s, oop obj) {
 194   T* referent_addr   = (T*) java_lang_ref_Reference::referent_addr_raw(obj);
 195   T* next_addr       = (T*) java_lang_ref_Reference::next_addr_raw(obj);
 196   T* discovered_addr = (T*) java_lang_ref_Reference::discovered_addr_raw(obj);
 197 
 198   log_develop_trace(gc, ref)("InstanceRefKlass %s for obj " PTR_FORMAT, s, p2i(obj));
 199   log_develop_trace(gc, ref)("     referent_addr/* " PTR_FORMAT " / " PTR_FORMAT,
 200       p2i(referent_addr), p2i(referent_addr ? (void*)RawAccess<>::oop_load(referent_addr) : NULL));
 201   log_develop_trace(gc, ref)("     next_addr/* " PTR_FORMAT " / " PTR_FORMAT,
 202       p2i(next_addr), p2i(next_addr ? (void*)RawAccess<>::oop_load(next_addr) : NULL));
 203   log_develop_trace(gc, ref)("     discovered_addr/* " PTR_FORMAT " / " PTR_FORMAT,
 204       p2i(discovered_addr), p2i(discovered_addr ? (void*)RawAccess<>::oop_load(discovered_addr) : NULL));
 205 }
 206 #endif
 207 
 208 // Macro to define InstanceRefKlass::oop_oop_iterate for virtual/nonvirtual for
 209 // all closures.  Macros calling macros above for each oop size.
 210 #define ALL_INSTANCE_REF_KLASS_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix)  \
 211   OOP_OOP_ITERATE_DEFN(          InstanceRefKlass, OopClosureType, nv_suffix)   \
 212   OOP_OOP_ITERATE_DEFN_BOUNDED(  InstanceRefKlass, OopClosureType, nv_suffix)   \
 213   OOP_OOP_ITERATE_DEFN_BACKWARDS(InstanceRefKlass, OopClosureType, nv_suffix)
 214 
 215 #endif // SHARE_VM_OOPS_INSTANCEREFKLASS_INLINE_HPP