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 /*

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  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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  * published by the Free Software Foundation.

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  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

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 #ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_INLINE_HPP

 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_INLINE_HPP

 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp"

 #include "gc_implementation/parallelScavenge/psScavenge.hpp"

 inline PSPromotionManager* PSPromotionManager::manager_array(int index) {

   assert(_manager_array != NULL, "access of NULL manager_array");

   assert(index >= 0 && index <= (int)ParallelGCThreads, "out of range manager_array access");

   return _manager_array[index];

 }

 template <class T>

 inline void PSPromotionManager::claim_or_forward_internal_depth(T* p) {

   if (p != NULL) { // XXX: error if p != NULL here

     oop o = oopDesc::load_decode_heap_oop_not_null(p);

     if (o->is_forwarded()) {

       o = o->forwardee();

       // Card mark

       if (PSScavenge::is_obj_in_young((HeapWord*) o)) {

         PSScavenge::card_table()->inline_write_ref_field_gc(p, o);

       }

       oopDesc::encode_store_heap_oop_not_null(p, o);

     } else {

       push_depth(p);

     }

   }

 }

 template <class T>

 inline void PSPromotionManager::claim_or_forward_depth(T* p) {

   assert(PSScavenge::should_scavenge(p, true), "revisiting object?");

   assert(Universe::heap()->kind() == CollectedHeap::ParallelScavengeHeap,

          "Sanity");

   assert(Universe::heap()->is_in(p), "pointer outside heap");

   claim_or_forward_internal_depth(p);

 }

 //

 // This method is pretty bulky. It would be nice to split it up

 // into smaller submethods, but we need to be careful not to hurt

 // performance.

 //

 template<bool promote_immediately>

 oop PSPromotionManager::copy_to_survivor_space(oop o) {

   assert(PSScavenge::should_scavenge(&o), "Sanity");

   oop new_obj = NULL;

   // NOTE! We must be very careful with any methods that access the mark

   // in o. There may be multiple threads racing on it, and it may be forwarded

   // at any time. Do not use oop methods for accessing the mark!

   markOop test_mark = o->mark();

   // The same test as "o->is_forwarded()"

   if (!test_mark->is_marked()) {

     bool new_obj_is_tenured = false;

     size_t new_obj_size = o->size();

     if (!promote_immediately) {

       // Find the objects age, MT safe.

       int age = (test_mark->has_displaced_mark_helper() /* o->has_displaced_mark() */) ?

         test_mark->displaced_mark_helper()->age() : test_mark->age();

       // Try allocating obj in to-space (unless too old)

       if (age < PSScavenge::tenuring_threshold()) {

         new_obj = (oop) _young_lab.allocate(new_obj_size);

         if (new_obj == NULL && !_young_gen_is_full) {

           // Do we allocate directly, or flush and refill?

           if (new_obj_size > (YoungPLABSize / 2)) {

             // Allocate this object directly

             new_obj = (oop)young_space()->cas_allocate(new_obj_size);

           } else {

             // Flush and fill

             _young_lab.flush();

             HeapWord* lab_base = young_space()->cas_allocate(YoungPLABSize);

             if (lab_base != NULL) {

               _young_lab.initialize(MemRegion(lab_base, YoungPLABSize));

               // Try the young lab allocation again.

               new_obj = (oop) _young_lab.allocate(new_obj_size);

             } else {

               _young_gen_is_full = true;

             }

           }

         }

       }

     }

     // Otherwise try allocating obj tenured

     if (new_obj == NULL) {

 #ifndef PRODUCT

       if (Universe::heap()->promotion_should_fail()) {

         return oop_promotion_failed(o, test_mark);

       }

 #endif  // #ifndef PRODUCT

       new_obj = (oop) _old_lab.allocate(new_obj_size);

       new_obj_is_tenured = true;

       if (new_obj == NULL) {

         if (!_old_gen_is_full) {

           // Do we allocate directly, or flush and refill?

           if (new_obj_size > (OldPLABSize / 2)) {

             // Allocate this object directly

             new_obj = (oop)old_gen()->cas_allocate(new_obj_size);

           } else {

             // Flush and fill

             _old_lab.flush();

             HeapWord* lab_base = old_gen()->cas_allocate(OldPLABSize);

             if(lab_base != NULL) {

               _old_lab.initialize(MemRegion(lab_base, OldPLABSize));

               // Try the old lab allocation again.

               new_obj = (oop) _old_lab.allocate(new_obj_size);

             }

           }

         }

         // This is the promotion failed test, and code handling.

         // The code belongs here for two reasons. It is slightly

         // different thatn the code below, and cannot share the

         // CAS testing code. Keeping the code here also minimizes

         // the impact on the common case fast path code.

         if (new_obj == NULL) {

           _old_gen_is_full = true;

           return oop_promotion_failed(o, test_mark);

         }

       }

     }

     assert(new_obj != NULL, "allocation should have succeeded");

     // Copy obj

     Copy::aligned_disjoint_words((HeapWord*)o, (HeapWord*)new_obj, new_obj_size);

     // Now we have to CAS in the header.

     if (o->cas_forward_to(new_obj, test_mark)) {

       // We won any races, we "own" this object.

       assert(new_obj == o->forwardee(), "Sanity");

       // Increment age if obj still in new generation. Now that

       // we're dealing with a markOop that cannot change, it is

       // okay to use the non mt safe oop methods.

       if (!new_obj_is_tenured) {

         new_obj->incr_age();

         assert(young_space()->contains(new_obj), "Attempt to push non-promoted obj");

       }

       // Do the size comparison first with new_obj_size, which we

       // already have. Hopefully, only a few objects are larger than

       // _min_array_size_for_chunking, and most of them will be arrays.

       // So, the is->objArray() test would be very infrequent.

       if (new_obj_size > _min_array_size_for_chunking &&

           new_obj->is_objArray() &&

           PSChunkLargeArrays) {

         // we'll chunk it

         oop* const masked_o = mask_chunked_array_oop(o);

         push_depth(masked_o);

         TASKQUEUE_STATS_ONLY(++_arrays_chunked; ++_masked_pushes);

       } else {

         // we'll just push its contents

         new_obj->push_contents(this);

       }

     }  else {

       // We lost, someone else "owns" this object

       guarantee(o->is_forwarded(), "Object must be forwarded if the cas failed.");

       // Try to deallocate the space.  If it was directly allocated we cannot

       // deallocate it, so we have to test.  If the deallocation fails,

       // overwrite with a filler object.

       if (new_obj_is_tenured) {

         if (!_old_lab.unallocate_object((HeapWord*) new_obj, new_obj_size)) {

           CollectedHeap::fill_with_object((HeapWord*) new_obj, new_obj_size);

         }

       } else if (!_young_lab.unallocate_object((HeapWord*) new_obj, new_obj_size)) {

         CollectedHeap::fill_with_object((HeapWord*) new_obj, new_obj_size);

       }

       // don't update this before the unallocation!

       new_obj = o->forwardee();

     }

   } else {

     assert(o->is_forwarded(), "Sanity");

     new_obj = o->forwardee();

   }

 #ifdef DEBUG

   // This code must come after the CAS test, or it will print incorrect

   // information.

   if (TraceScavenge) {

     gclog_or_tty->print_cr("{%s %s " PTR_FORMAT " -> " PTR_FORMAT " (" SIZE_FORMAT ")}",

        PSScavenge::should_scavenge(&new_obj) ? "copying" : "tenuring",

        new_obj->blueprint()->internal_name(), o, new_obj, new_obj->size());

   }

 #endif

   return new_obj;

 }

 inline void PSPromotionManager::process_popped_location_depth(StarTask p) {

   if (is_oop_masked(p)) {

     assert(PSChunkLargeArrays, "invariant");

     oop const old = unmask_chunked_array_oop(p);

     process_array_chunk(old);

   } else {

     if (p.is_narrow()) {

       assert(UseCompressedOops, "Error");

       PSScavenge::copy_and_push_safe_barrier<narrowOop, /*promote_immediately=*/false>(this, p);

     } else {

       PSScavenge::copy_and_push_safe_barrier<oop, /*promote_immediately=*/false>(this, p);

     }

   }

 }

 #if TASKQUEUE_STATS

 void PSPromotionManager::record_steal(StarTask& p) {

   if (is_oop_masked(p)) {

     ++_masked_steals;

   }

 }

 #endif // TASKQUEUE_STATS

 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_INLINE_HPP