--- a/src/hotspot/share/gc/cms/promotionInfo.hpp Fri Nov 08 14:54:17 2019 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,188 +0,0 @@
-/*
- * Copyright (c) 2010, 2019, 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_GC_CMS_PROMOTIONINFO_HPP
-#define SHARE_GC_CMS_PROMOTIONINFO_HPP
-
-#include "gc/cms/freeChunk.hpp"
-
-// Forward declarations
-class CompactibleFreeListSpace;
-
-class PromotedObject {
- private:
- enum {
- promoted_mask = right_n_bits(2), // i.e. 0x3
- displaced_mark = nth_bit(2), // i.e. 0x4
- next_mask = ~(right_n_bits(3)) // i.e. ~(0x7)
- };
-
- // Below, we want _narrow_next in the "higher" 32 bit slot,
- // whose position will depend on endian-ness of the platform.
- // This is so that there is no interference with the
- // cms_free_bit occupying bit position 7 (lsb == 0)
- // when we are using compressed oops; see FreeChunk::is_free().
- // We cannot move the cms_free_bit down because currently
- // biased locking code assumes that age bits are contiguous
- // with the lock bits. Even if that assumption were relaxed,
- // the least position we could move this bit to would be
- // to bit position 3, which would require 16 byte alignment.
- typedef struct {
-#ifdef VM_LITTLE_ENDIAN
- LP64_ONLY(narrowOop _pad;)
- narrowOop _narrow_next;
-#else
- narrowOop _narrow_next;
- LP64_ONLY(narrowOop _pad;)
-#endif
- } Data;
-
- union {
- intptr_t _next;
- Data _data;
- };
- public:
- PromotedObject* next() const;
- void setNext(PromotedObject* x);
- inline void setPromotedMark() {
- _next |= promoted_mask;
- assert(!((FreeChunk*)this)->is_free(), "Error");
- }
- inline bool hasPromotedMark() const {
- assert(!((FreeChunk*)this)->is_free(), "Error");
- return (_next & promoted_mask) == promoted_mask;
- }
- inline void setDisplacedMark() {
- _next |= displaced_mark;
- assert(!((FreeChunk*)this)->is_free(), "Error");
- }
- inline bool hasDisplacedMark() const {
- assert(!((FreeChunk*)this)->is_free(), "Error");
- return (_next & displaced_mark) != 0;
- }
- inline void clear_next() {
- _next = 0;
- assert(!((FreeChunk*)this)->is_free(), "Error");
- }
- debug_only(void *next_addr() { return (void *) &_next; })
-};
-
-class SpoolBlock: public FreeChunk {
- friend class PromotionInfo;
- protected:
- SpoolBlock* nextSpoolBlock;
- size_t bufferSize; // number of usable words in this block
- markWord* displacedHdr; // the displaced headers start here
-
- // Note about bufferSize: it denotes the number of entries available plus 1;
- // legal indices range from 1 through BufferSize - 1. See the verification
- // code verify() that counts the number of displaced headers spooled.
- size_t computeBufferSize() {
- return (size() * sizeof(HeapWord) - sizeof(*this)) / sizeof(markWord);
- }
-
- public:
- void init() {
- bufferSize = computeBufferSize();
- displacedHdr = (markWord*)&displacedHdr;
- nextSpoolBlock = NULL;
- }
-
- void print_on(outputStream* st) const;
- void print() const { print_on(tty); }
-};
-
-class PromotionInfo {
- bool _tracking; // set if tracking
- CompactibleFreeListSpace* _space; // the space to which this belongs
- PromotedObject* _promoHead; // head of list of promoted objects
- PromotedObject* _promoTail; // tail of list of promoted objects
- SpoolBlock* _spoolHead; // first spooling block
- SpoolBlock* _spoolTail; // last non-full spooling block or null
- SpoolBlock* _splice_point; // when _spoolTail is null, holds list tail
- SpoolBlock* _spareSpool; // free spool buffer
- size_t _firstIndex; // first active index in
- // first spooling block (_spoolHead)
- size_t _nextIndex; // last active index + 1 in last
- // spooling block (_spoolTail)
- private:
- // ensure that spooling space exists; return true if there is spooling space
- bool ensure_spooling_space_work();
-
- public:
- PromotionInfo() :
- _tracking(0), _space(NULL),
- _promoHead(NULL), _promoTail(NULL),
- _spoolHead(NULL), _spoolTail(NULL),
- _spareSpool(NULL), _firstIndex(1),
- _nextIndex(1) {}
-
- bool noPromotions() const {
- assert(_promoHead != NULL || _promoTail == NULL, "list inconsistency");
- return _promoHead == NULL;
- }
- void startTrackingPromotions();
- void stopTrackingPromotions();
- bool tracking() const { return _tracking; }
- void track(PromotedObject* trackOop); // keep track of a promoted oop
- // The following variant must be used when trackOop is not fully
- // initialized and has a NULL klass:
- void track(PromotedObject* trackOop, Klass* klassOfOop); // keep track of a promoted oop
- void setSpace(CompactibleFreeListSpace* sp) { _space = sp; }
- CompactibleFreeListSpace* space() const { return _space; }
- markWord nextDisplacedHeader(); // get next header & forward spool pointer
- void saveDisplacedHeader(markWord hdr);
- // save header and forward spool
-
- inline size_t refillSize() const;
-
- SpoolBlock* getSpoolBlock(); // return a free spooling block
- inline bool has_spooling_space() {
- return _spoolTail != NULL && _spoolTail->bufferSize > _nextIndex;
- }
- // ensure that spooling space exists
- bool ensure_spooling_space() {
- return has_spooling_space() || ensure_spooling_space_work();
- }
-
- template <typename OopClosureType>
- void promoted_oops_iterate(OopClosureType* cl);
-
- void verify() const;
- void reset() {
- _promoHead = NULL;
- _promoTail = NULL;
- _spoolHead = NULL;
- _spoolTail = NULL;
- _spareSpool = NULL;
- _firstIndex = 0;
- _nextIndex = 0;
-
- }
-
- void print_on(outputStream* st) const;
-};
-
-
-#endif // SHARE_GC_CMS_PROMOTIONINFO_HPP