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