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(Thread* thread, type* obj) : _value(obj), _thread(thread) { \
  59   if (obj != NULL) {                                                   \
  60     assert(((Metadata*)obj)->is_valid(), "obj is valid");              \
  61     assert(_thread == Thread::current(), "thread must be current");    \
  62     assert (_thread->is_in_stack((address)this), "not on stack?");     \
  63     _thread->metadata_handles()->push((Metadata*)obj);                 \
  64   }                                                                    \
  65 }                                                                      \
  66 
  67 DEF_METADATA_HANDLE_FN(method, Method)
  68 DEF_METADATA_HANDLE_FN(constantPool, ConstantPool)
  69 
  70 inline HandleMark::HandleMark() {
  71   initialize(Thread::current());
  72 }
  73 
  74 inline void HandleMark::push() {
  75   // This is intentionally a NOP. pop_and_restore will reset
  76   // values to the HandleMark further down the stack, typically
  77   // in JavaCalls::call_helper.
  78   debug_only(_area->_handle_mark_nesting++);
  79 }
  80 
  81 inline void HandleMark::pop_and_restore() {
  82   // Delete later chunks
  83   if(_chunk->next() != NULL) {
  84     assert(_area->size_in_bytes() > size_in_bytes(), "Sanity check");
  85     chop_later_chunks();
  86   } else {
  87     assert(_area->size_in_bytes() == size_in_bytes(), "Sanity check");
  88   }
  89   // Roll back arena to saved top markers
  90   _area->_chunk = _chunk;
  91   _area->_hwm = _hwm;
  92   _area->_max = _max;
  93   debug_only(_area->_handle_mark_nesting--);
  94 }
  95 
  96 inline HandleMarkCleaner::HandleMarkCleaner(Thread* thread) {
  97   _thread = thread;
  98   _thread->last_handle_mark()->push();
  99 }
 100 
 101 inline HandleMarkCleaner::~HandleMarkCleaner() {
 102   _thread->last_handle_mark()->pop_and_restore();
 103 }
 104 
 105 #endif // SHARE_RUNTIME_HANDLES_INLINE_HPP