1 /*
   2  * Copyright (c) 1998, 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 #ifndef SHARE_VM_RUNTIME_HANDLES_INLINE_HPP
  26 #define SHARE_VM_RUNTIME_HANDLES_INLINE_HPP
  27 
  28 #include "runtime/handles.hpp"
  29 #include "runtime/thread.inline.hpp"
  30 
  31 // these inline functions are in a separate file to break an include cycle
  32 // between Thread and Handle
  33 
  34 inline Handle::Handle(Thread* thread, oop obj) {
  35   assert(thread == Thread::current(), "sanity check");
  36   if (obj == NULL) {
  37     _handle = NULL;
  38   } else {
  39     _handle = thread->handle_area()->allocate_handle(obj);
  40   }
  41 }
  42 
  43 // Inline constructors for Specific Handles for different oop types
  44 #define DEF_HANDLE_CONSTR(type, is_a)                   \
  45 inline type##Handle::type##Handle (Thread* thread, type##Oop obj) : Handle(thread, (oop)obj) { \
  46   assert(is_null() || ((oop)obj)->is_a(), "illegal type");                \
  47 }
  48 
  49 DEF_HANDLE_CONSTR(instance , is_instance_noinline )
  50 DEF_HANDLE_CONSTR(array    , is_array_noinline    )
  51 DEF_HANDLE_CONSTR(objArray , is_objArray_noinline )
  52 DEF_HANDLE_CONSTR(typeArray, is_typeArray_noinline)
  53 
  54 // Constructor for metadata handles
  55 #define DEF_METADATA_HANDLE_FN(name, type) \
  56 inline name##Handle::name##Handle(type* obj) : _value(obj), _thread(NULL) {       \
  57   if (obj != NULL) {                                                   \
  58     assert(((Metadata*)obj)->is_valid(), "obj is valid");              \
  59     _thread = Thread::current();                                       \
  60     assert (_thread->is_in_stack((address)this), "not on stack?");     \
  61     _thread->metadata_handles()->push((Metadata*)obj);                 \
  62   }                                                                    \
  63 }                                                                      \
  64 inline name##Handle::name##Handle(Thread* thread, type* obj) : _value(obj), _thread(thread) { \
  65   if (obj != NULL) {                                                   \
  66     assert(((Metadata*)obj)->is_valid(), "obj is valid");              \
  67     assert(_thread == Thread::current(), "thread must be current");    \
  68     assert (_thread->is_in_stack((address)this), "not on stack?");     \
  69     _thread->metadata_handles()->push((Metadata*)obj);                 \
  70   }                                                                    \
  71 }                                                                      \
  72 
  73 DEF_METADATA_HANDLE_FN(method, Method)
  74 DEF_METADATA_HANDLE_FN(constantPool, ConstantPool)
  75 
  76 inline HandleMark::HandleMark() {
  77   initialize(Thread::current());
  78 }
  79 
  80 
  81 inline void HandleMark::push() {
  82   // This is intentionally a NOP. pop_and_restore will reset
  83   // values to the HandleMark further down the stack, typically
  84   // in JavaCalls::call_helper.
  85   debug_only(_area->_handle_mark_nesting++);
  86 }
  87 
  88 inline void HandleMark::pop_and_restore() {
  89   HandleArea* area = _area;   // help compilers with poor alias analysis
  90   // Delete later chunks
  91   if( _chunk->next() ) {
  92     // reset arena size before delete chunks. Otherwise, the total
  93     // arena size could exceed total chunk size
  94     assert(area->size_in_bytes() > size_in_bytes(), "Sanity check");
  95     area->set_size_in_bytes(size_in_bytes());
  96     _chunk->next_chop();
  97   } else {
  98     assert(area->size_in_bytes() == size_in_bytes(), "Sanity check");
  99   }
 100   // Roll back arena to saved top markers
 101   area->_chunk = _chunk;
 102   area->_hwm = _hwm;
 103   area->_max = _max;
 104   debug_only(area->_handle_mark_nesting--);
 105 }
 106 
 107 inline HandleMarkCleaner::HandleMarkCleaner(Thread* thread) {
 108   _thread = thread;
 109   _thread->last_handle_mark()->push();
 110 }
 111 
 112 inline HandleMarkCleaner::~HandleMarkCleaner() {
 113   _thread->last_handle_mark()->pop_and_restore();
 114 }
 115 
 116 #endif // SHARE_VM_RUNTIME_HANDLES_INLINE_HPP