| /* |
| * Copyright (c) 2002, 2012, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * 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. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONLAB_HPP |
| #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONLAB_HPP |
| |
| #include "gc_implementation/parallelScavenge/objectStartArray.hpp" |
| #include "gc_interface/collectedHeap.inline.hpp" |
| #include "memory/allocation.hpp" |
| |
| // |
| // PSPromotionLAB is a parallel scavenge promotion lab. This class acts very |
| // much like a MutableSpace. We couldn't embed a MutableSpace, though, as |
| // it has a considerable number of asserts and invariants that are violated. |
| // |
| |
| class ObjectStartArray; |
| |
| class PSPromotionLAB : public CHeapObj<mtGC> { |
| protected: |
| static size_t filler_header_size; |
| |
| enum LabState { |
| needs_flush, |
| flushed, |
| zero_size |
| }; |
| |
| HeapWord* _top; |
| HeapWord* _bottom; |
| HeapWord* _end; |
| LabState _state; |
| |
| void set_top(HeapWord* value) { _top = value; } |
| void set_bottom(HeapWord* value) { _bottom = value; } |
| void set_end(HeapWord* value) { _end = value; } |
| |
| // The shared initialize code invokes this. |
| debug_only(virtual bool lab_is_valid(MemRegion lab) { return false; }); |
| |
| PSPromotionLAB() : _top(NULL), _bottom(NULL), _end(NULL) { } |
| |
| public: |
| // Filling and flushing. |
| void initialize(MemRegion lab); |
| |
| virtual void flush(); |
| |
| // Accessors |
| HeapWord* bottom() const { return _bottom; } |
| HeapWord* end() const { return _end; } |
| HeapWord* top() const { return _top; } |
| |
| bool is_flushed() { return _state == flushed; } |
| |
| bool unallocate_object(HeapWord* obj, size_t obj_size); |
| |
| // Returns a subregion containing all objects in this space. |
| MemRegion used_region() { return MemRegion(bottom(), top()); } |
| |
| // Boolean querries. |
| bool is_empty() const { return used() == 0; } |
| bool not_empty() const { return used() > 0; } |
| bool contains(const void* p) const { return _bottom <= p && p < _end; } |
| |
| // Size computations. Sizes are in bytes. |
| size_t capacity() const { return byte_size(bottom(), end()); } |
| size_t used() const { return byte_size(bottom(), top()); } |
| size_t free() const { return byte_size(top(), end()); } |
| }; |
| |
| class PSYoungPromotionLAB : public PSPromotionLAB { |
| public: |
| PSYoungPromotionLAB() { } |
| |
| // Not MT safe |
| inline HeapWord* allocate(size_t size); |
| |
| debug_only(virtual bool lab_is_valid(MemRegion lab);) |
| }; |
| |
| class PSOldPromotionLAB : public PSPromotionLAB { |
| private: |
| ObjectStartArray* _start_array; |
| |
| public: |
| PSOldPromotionLAB() : _start_array(NULL) { } |
| PSOldPromotionLAB(ObjectStartArray* start_array) : _start_array(start_array) { } |
| |
| void set_start_array(ObjectStartArray* start_array) { _start_array = start_array; } |
| |
| void flush(); |
| |
| // Not MT safe |
| HeapWord* allocate(size_t size) { |
| // Cannot test for this now that we're doing promotion failures |
| // assert(_state != flushed, "Sanity"); |
| assert(_start_array != NULL, "Sanity"); |
| HeapWord* obj = top(); |
| HeapWord* new_top = obj + size; |
| // The 'new_top>obj' check is needed to detect overflow of obj+size. |
| if (new_top > obj && new_top <= end()) { |
| set_top(new_top); |
| assert(is_object_aligned((intptr_t)obj) && is_object_aligned((intptr_t)new_top), |
| "checking alignment"); |
| _start_array->allocate_block(obj); |
| return obj; |
| } |
| |
| return NULL; |
| } |
| |
| debug_only(virtual bool lab_is_valid(MemRegion lab)); |
| }; |
| |
| #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONLAB_HPP |