1 /*
   2  * Copyright (c) 1998, 2019, 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_RUNTIME_HANDLES_INLINE_HPP
  26 #define SHARE_RUNTIME_HANDLES_INLINE_HPP
  27 
  28 #include "runtime/handles.hpp"
  29 #include "runtime/thread.hpp"
  30 #include "oops/metadata.hpp"
  31 #include "oops/oop.hpp"
  32 
  33 // these inline functions are in a separate file to break an include cycle
  34 // between Thread and Handle
  35 
  36 inline Handle::Handle(Thread* thread, oop obj) {
  37   assert(thread == Thread::current(), "sanity check");
  38   if (obj == NULL) {
  39     _handle = NULL;
  40   } else {
  41     _handle = thread->handle_area()->allocate_handle(obj);
  42   }
  43 }
  44 
  45 // Inline constructors for Specific Handles for different oop types
  46 #define DEF_HANDLE_CONSTR(type, is_a)                   \
  47 inline type##Handle::type##Handle (Thread* thread, type##Oop obj) : Handle(thread, (oop)obj) { \
  48   assert(is_null() || ((oop)obj)->is_a(), "illegal type");                \
  49 }
  50 
  51 DEF_HANDLE_CONSTR(instance , is_instance_noinline )
  52 DEF_HANDLE_CONSTR(array    , is_array_noinline    )
  53 DEF_HANDLE_CONSTR(objArray , is_objArray_noinline )
  54 DEF_HANDLE_CONSTR(typeArray, is_typeArray_noinline)
  55 
  56 // Constructor for metadata handles
  57 #define DEF_METADATA_HANDLE_FN(name, type) \
  58 inline name##Handle::name##Handle(type* obj) : _value(obj), _thread(NULL) {       \
  59   if (obj != NULL) {                                                   \
  60     assert(((Metadata*)obj)->is_valid(), "obj is valid");              \
  61     _thread = Thread::current();                                       \
  62     assert (_thread->is_in_stack((address)this), "not on stack?");     \
  63     _thread->metadata_handles()->push((Metadata*)obj);                 \
  64   }                                                                    \
  65 }                                                                      \
  66 inline name##Handle::name##Handle(Thread* thread, type* obj) : _value(obj), _thread(thread) { \
  67   if (obj != NULL) {                                                   \
  68     assert(((Metadata*)obj)->is_valid(), "obj is valid");              \
  69     assert(_thread == Thread::current(), "thread must be current");    \
  70     assert (_thread->is_in_stack((address)this), "not on stack?");     \
  71     _thread->metadata_handles()->push((Metadata*)obj);                 \
  72   }                                                                    \
  73 }                                                                      \
  74 
  75 DEF_METADATA_HANDLE_FN(method, Method)
  76 DEF_METADATA_HANDLE_FN(constantPool, ConstantPool)
  77 
  78 inline HandleMark::HandleMark() {
  79   initialize(Thread::current());
  80 }
  81 
  82 inline void HandleMark::push() {
  83   // This is intentionally a NOP. pop_and_restore will reset
  84   // values to the HandleMark further down the stack, typically
  85   // in JavaCalls::call_helper.
  86   debug_only(_area->_handle_mark_nesting++);
  87 }
  88 
  89 inline void HandleMark::pop_and_restore() {
  90   // Delete later chunks
  91   if(_chunk->next() != NULL) {
  92     assert(_area->size_in_bytes() > size_in_bytes(), "Sanity check");
  93     chop_later_chunks();
  94   } else {
  95     assert(_area->size_in_bytes() == size_in_bytes(), "Sanity check");
  96   }
  97   // Roll back arena to saved top markers
  98   _area->_chunk = _chunk;
  99   _area->_hwm = _hwm;
 100   _area->_max = _max;
 101   debug_only(_area->_handle_mark_nesting--);
 102 }
 103 
 104 inline HandleMarkCleaner::HandleMarkCleaner(Thread* thread) {
 105   _thread = thread;
 106   _thread->last_handle_mark()->push();
 107 }
 108 
 109 inline HandleMarkCleaner::~HandleMarkCleaner() {
 110   _thread->last_handle_mark()->pop_and_restore();
 111 }
 112 
 113 #endif // SHARE_RUNTIME_HANDLES_INLINE_HPP