1 /*
   2  * Copyright (c) 1997, 2015, 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 "oops/oop.inline.hpp"
  29 #include "oops/verifyOopClosure.hpp"
  30 #include "runtime/handles.inline.hpp"
  31 #include "runtime/thread.inline.hpp"
  32 #include "utilities/copy.hpp"
  33 
  34 bool always_do_update_barrier = false;
  35 
  36 BarrierSet* oopDesc::_bs = NULL;
  37 
  38 void oopDesc::print_on(outputStream* st) const {
  39   if (this == NULL) {
  40     st->print_cr("NULL");
  41   } else {
  42     klass()->oop_print_on(oop(this), st);
  43   }
  44 }
  45 
  46 void oopDesc::print_address_on(outputStream* st) const {
  47   if (PrintOopAddress) {
  48     st->print("{" INTPTR_FORMAT "}", p2i(this));
  49   }
  50 }
  51 
  52 void oopDesc::print()         { print_on(tty);         }
  53 
  54 void oopDesc::print_address() { print_address_on(tty); }
  55 
  56 char* oopDesc::print_string() {
  57   stringStream st;
  58   print_on(&st);
  59   return st.as_string();
  60 }
  61 
  62 void oopDesc::print_value() {
  63   print_value_on(tty);
  64 }
  65 
  66 char* oopDesc::print_value_string() {
  67   char buf[100];
  68   stringStream st(buf, sizeof(buf));
  69   print_value_on(&st);
  70   return st.as_string();
  71 }
  72 
  73 void oopDesc::print_value_on(outputStream* st) const {
  74   oop obj = oop(this);
  75   if (this == NULL) {
  76     st->print("NULL");
  77   } else if (java_lang_String::is_instance(obj)) {
  78     java_lang_String::print(obj, st);
  79     if (PrintOopAddress) print_address_on(st);
  80   } else {
  81     klass()->oop_print_value_on(obj, st);
  82   }
  83 }
  84 
  85 
  86 void oopDesc::verify_on(outputStream* st) {
  87   if (this != NULL) {
  88     klass()->oop_verify_on(this, st);
  89   }
  90 }
  91 
  92 
  93 void oopDesc::verify() {
  94   verify_on(tty);
  95 }
  96 
  97 intptr_t oopDesc::slow_identity_hash() {
  98   // slow case; we have to acquire the micro lock in order to locate the header
  99   ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
 100   HandleMark hm;
 101   Handle object(this);
 102   return ObjectSynchronizer::identity_hash_value_for(object);
 103 }
 104 
 105 // When String table needs to rehash
 106 unsigned int oopDesc::new_hash(juint seed) {
 107   EXCEPTION_MARK;
 108   ResourceMark rm;
 109   int length;
 110   jchar* chars = java_lang_String::as_unicode_string(this, length, THREAD);
 111   if (chars != NULL) {
 112     // Use alternate hashing algorithm on the string
 113     return AltHashing::murmur3_32(seed, chars, length);
 114   } else {
 115     vm_exit_out_of_memory(length, OOM_MALLOC_ERROR, "unable to create Unicode strings for String table rehash");
 116     return 0;
 117   }
 118 }
 119 
 120 VerifyOopClosure VerifyOopClosure::verify_oop;
 121 
 122 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
 123   oop obj = oopDesc::load_decode_heap_oop(p);
 124   guarantee(obj->is_oop_or_null(), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
 125 }
 126 
 127 void VerifyOopClosure::do_oop(oop* p)       { VerifyOopClosure::do_oop_work(p); }
 128 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
 129 
 130 // type test operations that doesn't require inclusion of oop.inline.hpp.
 131 bool oopDesc::is_instance_noinline()          const { return is_instance();            }
 132 bool oopDesc::is_array_noinline()             const { return is_array();               }
 133 bool oopDesc::is_objArray_noinline()          const { return is_objArray();            }
 134 bool oopDesc::is_typeArray_noinline()         const { return is_typeArray();           }
 135 
 136 bool oopDesc::has_klass_gap() {
 137   // Only has a klass gap when compressed class pointers are used.
 138   return UseCompressedClassPointers;
 139 }