1 /*
   2  * Copyright (c) 1997, 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 
  25 #include "precompiled.hpp"
  26 #include "classfile/altHashing.hpp"
  27 #include "classfile/javaClasses.inline.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "oops/oop.inline.hpp"
  30 #include "oops/verifyOopClosure.hpp"
  31 #include "runtime/access.inline.hpp"
  32 #include "runtime/handles.inline.hpp"
  33 #include "runtime/thread.inline.hpp"
  34 #include "utilities/copy.hpp"
  35 
  36 bool always_do_update_barrier = false;
  37 
  38 BarrierSet* oopDesc::_bs = NULL;
  39 
  40 void oopDesc::print_on(outputStream* st) const {
  41   if (this == NULL) {
  42     st->print_cr("NULL");
  43   } else {
  44     klass()->oop_print_on(oop(this), st);
  45   }
  46 }
  47 
  48 void oopDesc::print_address_on(outputStream* st) const {
  49   st->print("{" INTPTR_FORMAT "}", p2i(this));
  50 
  51 }
  52 
  53 void oopDesc::print()         { print_on(tty);         }
  54 
  55 void oopDesc::print_address() { print_address_on(tty); }
  56 
  57 char* oopDesc::print_string() {
  58   stringStream st;
  59   print_on(&st);
  60   return st.as_string();
  61 }
  62 
  63 void oopDesc::print_value() {
  64   print_value_on(tty);
  65 }
  66 
  67 char* oopDesc::print_value_string() {
  68   char buf[100];
  69   stringStream st(buf, sizeof(buf));
  70   print_value_on(&st);
  71   return st.as_string();
  72 }
  73 
  74 void oopDesc::print_value_on(outputStream* st) const {
  75   oop obj = oop(this);
  76   if (this == NULL) {
  77     st->print("NULL");
  78   } else if (java_lang_String::is_instance(obj)) {
  79     java_lang_String::print(obj, st);
  80     print_address_on(st);
  81   } else {
  82     klass()->oop_print_value_on(obj, st);
  83   }
  84 }
  85 
  86 
  87 void oopDesc::verify_on(outputStream* st) {
  88   if (this != NULL) {
  89     klass()->oop_verify_on(this, st);
  90   }
  91 }
  92 
  93 
  94 void oopDesc::verify() {
  95   verify_on(tty);
  96 }
  97 
  98 intptr_t oopDesc::slow_identity_hash() {
  99   // slow case; we have to acquire the micro lock in order to locate the header
 100   Thread* THREAD = Thread::current();
 101   ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
 102   HandleMark hm(THREAD);
 103   Handle object(THREAD, this);
 104   return ObjectSynchronizer::identity_hash_value_for(object);
 105 }
 106 
 107 // When String table needs to rehash
 108 unsigned int oopDesc::new_hash(juint seed) {
 109   EXCEPTION_MARK;
 110   ResourceMark rm;
 111   int length;
 112   jchar* chars = java_lang_String::as_unicode_string(this, length, THREAD);
 113   if (chars != NULL) {
 114     // Use alternate hashing algorithm on the string
 115     return AltHashing::murmur3_32(seed, chars, length);
 116   } else {
 117     vm_exit_out_of_memory(length, OOM_MALLOC_ERROR, "unable to create Unicode strings for String table rehash");
 118     return 0;
 119   }
 120 }
 121 
 122 VerifyOopClosure VerifyOopClosure::verify_oop;
 123 
 124 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
 125   oop obj = oopDesc::load_decode_heap_oop(p);
 126   guarantee(obj->is_oop_or_null(), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
 127 }
 128 
 129 void VerifyOopClosure::do_oop(oop* p)       { VerifyOopClosure::do_oop_work(p); }
 130 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
 131 
 132 // type test operations that doesn't require inclusion of oop.inline.hpp.
 133 bool oopDesc::is_instance_noinline()          const { return is_instance();            }
 134 bool oopDesc::is_array_noinline()             const { return is_array();               }
 135 bool oopDesc::is_objArray_noinline()          const { return is_objArray();            }
 136 bool oopDesc::is_typeArray_noinline()         const { return is_typeArray();           }
 137 
 138 bool oopDesc::has_klass_gap() {
 139   // Only has a klass gap when compressed class pointers are used.
 140   return UseCompressedClassPointers;
 141 }
 142 
 143 oop oopDesc::obj_field_acquire(int offset) const                   { return HeapAccess<MO_ACQUIRE>::oop_load_at(oop_base(), offset); }
 144 
 145 void oopDesc::obj_field_put_raw(int offset, oop value)             { BasicAccess<>::oop_store_at(oop_base(), offset, value); }
 146 void oopDesc::release_obj_field_put(int offset, oop value)         { HeapAccess<MO_RELEASE>::oop_store_at(oop_base(), offset, value); }
 147 void oopDesc::obj_field_put_volatile(int offset, oop value)        { HeapAccess<MO_SEQ_CST>::oop_store_at(oop_base(), offset, value); }
 148 
 149 address oopDesc::address_field(int offset) const                   { return HeapAccess<>::load_at(oop_base(), offset); }
 150 address oopDesc::address_field_acquire(int offset) const           { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 151 
 152 void oopDesc::address_field_put(int offset, address value)         { HeapAccess<>::store_at(oop_base(), offset, value); }
 153 void oopDesc::release_address_field_put(int offset, address value) { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, value); }
 154 
 155 Metadata* oopDesc::metadata_field(int offset) const                { return HeapAccess<>::load_at(oop_base(), offset); }
 156 void oopDesc::metadata_field_put(int offset, Metadata* value)      { HeapAccess<>::store_at(oop_base(), offset, value); }
 157 
 158 jbyte oopDesc::byte_field_acquire(int offset) const                { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 159 void oopDesc::release_byte_field_put(int offset, jbyte value)      { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, value); }
 160 
 161 jchar oopDesc::char_field_acquire(int offset) const                { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 162 void oopDesc::release_char_field_put(int offset, jchar value)      { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, value); }
 163 
 164 jboolean oopDesc::bool_field_acquire(int offset) const             { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 165 void oopDesc::release_bool_field_put(int offset, jboolean value)   { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, jboolean(value & 1)); }
 166 
 167 jint oopDesc::int_field_acquire(int offset) const                  { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 168 void oopDesc::release_int_field_put(int offset, jint value)        { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, value); }
 169 
 170 jshort oopDesc::short_field_acquire(int offset) const              { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 171 void oopDesc::release_short_field_put(int offset, jshort value)    { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, value); }
 172 
 173 jlong oopDesc::long_field_acquire(int offset) const                { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 174 void oopDesc::release_long_field_put(int offset, jlong value)      { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, value); }
 175 
 176 jfloat oopDesc::float_field_acquire(int offset) const              { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 177 void oopDesc::release_float_field_put(int offset, jfloat value)    { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, value); }
 178 
 179 jdouble oopDesc::double_field_acquire(int offset) const            { return HeapAccess<MO_ACQUIRE>::load_at(oop_base(), offset); }
 180 void oopDesc::release_double_field_put(int offset, jdouble value)  { HeapAccess<MO_RELEASE>::store_at(oop_base(), offset, value); }
 181 
 182 // These functions are only used to exchange oop fields in instances,
 183 // not headers.
 184 oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
 185   return HeapAccess<MO_SEQ_CST>::oop_swap(exchange_value, dest);
 186 }
 187 
 188 oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
 189                                          volatile HeapWord *dest,
 190                                          oop compare_value) {
 191   return HeapAccess<MO_SEQ_CST>::oop_cas(exchange_value, dest, compare_value);
 192 }