1 /*
   2  * Copyright (c) 1997, 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 #include "precompiled.hpp"
  26 #include "classfile/altHashing.hpp"
  27 #include "classfile/javaClasses.inline.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "oops/access.inline.hpp"
  30 #include "oops/oop.inline.hpp"
  31 #include "oops/verifyOopClosure.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 void oopDesc::print_on(outputStream* st) const {
  39   klass()->oop_print_on(oop(this), st);
  40 }
  41 
  42 void oopDesc::print_address_on(outputStream* st) const {
  43   st->print("{" INTPTR_FORMAT "}", p2i(this));
  44 
  45 }
  46 
  47 void oopDesc::print()         { print_on(tty);         }
  48 
  49 void oopDesc::print_address() { print_address_on(tty); }
  50 
  51 char* oopDesc::print_string() {
  52   stringStream st;
  53   print_on(&st);
  54   return st.as_string();
  55 }
  56 
  57 void oopDesc::print_value() {
  58   print_value_on(tty);
  59 }
  60 
  61 char* oopDesc::print_value_string() {
  62   char buf[100];
  63   stringStream st(buf, sizeof(buf));
  64   print_value_on(&st);
  65   return st.as_string();
  66 }
  67 
  68 void oopDesc::print_value_on(outputStream* st) const {
  69   oop obj = oop(this);
  70   if (java_lang_String::is_instance(obj)) {
  71     java_lang_String::print(obj, st);
  72     print_address_on(st);
  73   } else {
  74     klass()->oop_print_value_on(obj, st);
  75   }
  76 }
  77 
  78 
  79 void oopDesc::verify_on(outputStream* st, oopDesc* oop_desc) {
  80   if (oop_desc != NULL) {
  81     oop_desc->klass()->oop_verify_on(oop_desc, st);
  82   }
  83 }
  84 
  85 
  86 void oopDesc::verify(oopDesc* oop_desc) {
  87   verify_on(tty, oop_desc);
  88 }
  89 
  90 intptr_t oopDesc::slow_identity_hash() {
  91   // slow case; we have to acquire the micro lock in order to locate the header
  92   Thread* THREAD = Thread::current();
  93   ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
  94   HandleMark hm(THREAD);
  95   Handle object(THREAD, this);
  96   return ObjectSynchronizer::FastHashCode(THREAD, object());
  97 }
  98 
  99 // When String table needs to rehash
 100 unsigned int oopDesc::new_hash(juint seed) {
 101   EXCEPTION_MARK;
 102   ResourceMark rm;
 103   int length;
 104   jchar* chars = java_lang_String::as_unicode_string(this, length, THREAD);
 105   if (chars != NULL) {
 106     // Use alternate hashing algorithm on the string
 107     return AltHashing::murmur3_32(seed, chars, length);
 108   } else {
 109     vm_exit_out_of_memory(length, OOM_MALLOC_ERROR, "unable to create Unicode strings for String table rehash");
 110     return 0;
 111   }
 112 }
 113 
 114 // used only for asserts and guarantees
 115 bool oopDesc::is_oop(oop obj, bool ignore_mark_word) {
 116   if (!Universe::heap()->is_oop(obj)) {
 117     return false;
 118   }
 119 
 120   // Header verification: the mark is typically non-NULL. If we're
 121   // at a safepoint, it must not be null.
 122   // Outside of a safepoint, the header could be changing (for example,
 123   // another thread could be inflating a lock on this object).
 124   if (ignore_mark_word) {
 125     return true;
 126   }
 127   if (obj->mark_raw() != NULL) {
 128     return true;
 129   }
 130   return !SafepointSynchronize::is_at_safepoint() ;
 131 }
 132 
 133 // used only for asserts and guarantees
 134 bool oopDesc::is_oop_or_null(oop obj, bool ignore_mark_word) {
 135   return obj == NULL ? true : is_oop(obj, ignore_mark_word);
 136 }
 137 
 138 #ifndef PRODUCT
 139 // used only for asserts
 140 bool oopDesc::is_unlocked_oop() const {
 141   if (!Universe::heap()->is_in_reserved(this)) return false;
 142   return mark()->is_unlocked();
 143 }
 144 #endif // PRODUCT
 145 
 146 VerifyOopClosure VerifyOopClosure::verify_oop;
 147 
 148 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
 149   oop obj = RawAccess<>::oop_load(p);
 150   guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
 151 }
 152 
 153 void VerifyOopClosure::do_oop(oop* p)       { VerifyOopClosure::do_oop_work(p); }
 154 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
 155 
 156 // type test operations that doesn't require inclusion of oop.inline.hpp.
 157 bool oopDesc::is_instance_noinline()          const { return is_instance();            }
 158 bool oopDesc::is_array_noinline()             const { return is_array();               }
 159 bool oopDesc::is_objArray_noinline()          const { return is_objArray();            }
 160 bool oopDesc::is_typeArray_noinline()         const { return is_typeArray();           }
 161 bool oopDesc::is_value_noinline()             const { return is_value();               }
 162 bool oopDesc::is_valueArray_noinline()        const { return is_valueArray();          }
 163 
 164 bool oopDesc::has_klass_gap() {
 165   // Only has a klass gap when compressed class pointers are used.
 166   return UseCompressedClassPointers;
 167 }
 168 
 169 oop oopDesc::obj_field_acquire(int offset) const                      { return HeapAccess<MO_ACQUIRE>::oop_load_at(as_oop(), offset); }
 170 
 171 void oopDesc::obj_field_put_raw(int offset, oop value)                { RawAccess<>::oop_store_at(as_oop(), offset, value); }
 172 void oopDesc::release_obj_field_put(int offset, oop value)            { HeapAccess<MO_RELEASE>::oop_store_at(as_oop(), offset, value); }
 173 void oopDesc::obj_field_put_volatile(int offset, oop value)           { HeapAccess<MO_SEQ_CST>::oop_store_at(as_oop(), offset, value); }
 174 
 175 address oopDesc::address_field(int offset) const                      { return HeapAccess<>::load_at(as_oop(), offset); }
 176 address oopDesc::address_field_acquire(int offset) const              { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 177 
 178 void oopDesc::address_field_put(int offset, address value)            { HeapAccess<>::store_at(as_oop(), offset, value); }
 179 void oopDesc::release_address_field_put(int offset, address value)    { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
 180 
 181 Metadata* oopDesc::metadata_field(int offset) const                   { return HeapAccess<>::load_at(as_oop(), offset); }
 182 Metadata* oopDesc::metadata_field_raw(int offset) const               { return RawAccess<>::load_at(as_oop(), offset); }
 183 void oopDesc::metadata_field_put(int offset, Metadata* value)         { HeapAccess<>::store_at(as_oop(), offset, value); }
 184 
 185 Metadata* oopDesc::metadata_field_acquire(int offset) const           { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 186 void oopDesc::release_metadata_field_put(int offset, Metadata* value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
 187 
 188 jbyte oopDesc::byte_field_acquire(int offset) const                   { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 189 void oopDesc::release_byte_field_put(int offset, jbyte value)         { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
 190 
 191 jchar oopDesc::char_field_acquire(int offset) const                   { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 192 void oopDesc::release_char_field_put(int offset, jchar value)         { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
 193 
 194 jboolean oopDesc::bool_field_acquire(int offset) const                { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 195 void oopDesc::release_bool_field_put(int offset, jboolean value)      { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, jboolean(value & 1)); }
 196 
 197 jint oopDesc::int_field_acquire(int offset) const                     { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 198 void oopDesc::release_int_field_put(int offset, jint value)           { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
 199 
 200 jshort oopDesc::short_field_acquire(int offset) const                 { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 201 void oopDesc::release_short_field_put(int offset, jshort value)       { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
 202 
 203 jlong oopDesc::long_field_acquire(int offset) const                   { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 204 void oopDesc::release_long_field_put(int offset, jlong value)         { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
 205 
 206 jfloat oopDesc::float_field_acquire(int offset) const                 { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 207 void oopDesc::release_float_field_put(int offset, jfloat value)       { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
 208 
 209 jdouble oopDesc::double_field_acquire(int offset) const               { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
 210 void oopDesc::release_double_field_put(int offset, jdouble value)     { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }