--- old/src/hotspot/share/gc/parallel/psMarkSweepDecorator.cpp	2019-12-18 16:37:07.321761812 +0100
+++ /dev/null	2019-12-18 13:30:34.338422670 +0100
@@ -1,395 +0,0 @@
-/*
- * Copyright (c) 2001, 2018, 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.
- *
- */
-
-#include "precompiled.hpp"
-#include "classfile/systemDictionary.hpp"
-#include "gc/parallel/objectStartArray.hpp"
-#include "gc/parallel/parallelScavengeHeap.hpp"
-#include "gc/parallel/parMarkBitMap.inline.hpp"
-#include "gc/parallel/psMarkSweep.hpp"
-#include "gc/parallel/psMarkSweepDecorator.hpp"
-#include "gc/parallel/psParallelCompact.inline.hpp"
-#include "gc/serial/markSweep.inline.hpp"
-#include "gc/shared/spaceDecorator.inline.hpp"
-#include "memory/iterator.inline.hpp"
-#include "oops/oop.inline.hpp"
-#include "runtime/prefetch.inline.hpp"
-
-PSMarkSweepDecorator* PSMarkSweepDecorator::_destination_decorator = NULL;
-
-
-void PSMarkSweepDecorator::set_destination_decorator_tenured() {
-  ParallelScavengeHeap* heap = ParallelScavengeHeap::heap();
-  _destination_decorator = heap->old_gen()->object_mark_sweep();
-}
-
-void PSMarkSweepDecorator::advance_destination_decorator() {
-  ParallelScavengeHeap* heap = ParallelScavengeHeap::heap();
-
-  assert(_destination_decorator != NULL, "Sanity");
-
-  PSMarkSweepDecorator* first = heap->old_gen()->object_mark_sweep();
-  PSMarkSweepDecorator* second = heap->young_gen()->eden_mark_sweep();
-  PSMarkSweepDecorator* third = heap->young_gen()->from_mark_sweep();
-  PSMarkSweepDecorator* fourth = heap->young_gen()->to_mark_sweep();
-
-  if ( _destination_decorator == first ) {
-    _destination_decorator = second;
-  } else if ( _destination_decorator == second ) {
-    _destination_decorator = third;
-  } else if ( _destination_decorator == third ) {
-    _destination_decorator = fourth;
-  } else {
-    fatal("PSMarkSweep attempting to advance past last compaction area");
-  }
-}
-
-PSMarkSweepDecorator* PSMarkSweepDecorator::destination_decorator() {
-  assert(_destination_decorator != NULL, "Sanity");
-
-  return _destination_decorator;
-}
-
-// FIX ME FIX ME FIX ME FIX ME!!!!!!!!!
-// The object forwarding code is duplicated. Factor this out!!!!!
-//
-// This method "precompacts" objects inside its space to dest. It places forwarding
-// pointers into markWords for use by adjust_pointers. If "dest" should overflow, we
-// finish by compacting into our own space.
-
-void PSMarkSweepDecorator::precompact() {
-  // Reset our own compact top.
-  set_compaction_top(space()->bottom());
-
-  /* We allow some amount of garbage towards the bottom of the space, so
-   * we don't start compacting before there is a significant gain to be made.
-   * Occasionally, we want to ensure a full compaction, which is determined
-   * by the MarkSweepAlwaysCompactCount parameter. This is a significant
-   * performance improvement!
-   */
-  bool skip_dead = ((PSMarkSweep::total_invocations() % MarkSweepAlwaysCompactCount) != 0);
-
-  size_t allowed_deadspace = 0;
-  if (skip_dead) {
-    const size_t ratio = allowed_dead_ratio();
-    allowed_deadspace = space()->capacity_in_words() * ratio / 100;
-  }
-
-  // Fetch the current destination decorator
-  PSMarkSweepDecorator* dest = destination_decorator();
-  ObjectStartArray* start_array = dest->start_array();
-
-  HeapWord* compact_top = dest->compaction_top();
-  HeapWord* compact_end = dest->space()->end();
-
-  HeapWord* q = space()->bottom();
-  HeapWord* t = space()->top();
-
-  HeapWord*  end_of_live= q;    /* One byte beyond the last byte of the last
-                                   live object. */
-  HeapWord*  first_dead = space()->end(); /* The first dead object. */
-
-  const intx interval = PrefetchScanIntervalInBytes;
-
-  while (q < t) {
-    assert(oop(q)->mark_raw().is_marked() || oop(q)->mark_raw().is_unlocked() ||
-           oop(q)->mark_raw().has_bias_pattern(),
-           "these are the only valid states during a mark sweep");
-    if (oop(q)->is_gc_marked()) {
-      /* prefetch beyond q */
-      Prefetch::write(q, interval);
-      size_t size = oop(q)->size();
-
-      size_t compaction_max_size = pointer_delta(compact_end, compact_top);
-
-      // This should only happen if a space in the young gen overflows the
-      // old gen. If that should happen, we null out the start_array, because
-      // the young spaces are not covered by one.
-      while(size > compaction_max_size) {
-        // First record the last compact_top
-        dest->set_compaction_top(compact_top);
-
-        // Advance to the next compaction decorator
-        advance_destination_decorator();
-        dest = destination_decorator();
-
-        // Update compaction info
-        start_array = dest->start_array();
-        compact_top = dest->compaction_top();
-        compact_end = dest->space()->end();
-        assert(compact_top == dest->space()->bottom(), "Advanced to space already in use");
-        assert(compact_end > compact_top, "Must always be space remaining");
-        compaction_max_size =
-          pointer_delta(compact_end, compact_top);
-      }
-
-      // store the forwarding pointer into the mark word
-      if (q != compact_top) {
-        oop(q)->forward_to(oop(compact_top));
-        assert(oop(q)->is_gc_marked(), "encoding the pointer should preserve the mark");
-      } else {
-        // if the object isn't moving we can just set the mark to the default
-        // mark and handle it specially later on.
-        oop(q)->init_mark_raw();
-        assert(oop(q)->forwardee() == NULL, "should be forwarded to NULL");
-      }
-
-      // Update object start array
-      if (start_array) {
-        start_array->allocate_block(compact_top);
-      }
-
-      compact_top += size;
-      assert(compact_top <= dest->space()->end(),
-        "Exceeding space in destination");
-
-      q += size;
-      end_of_live = q;
-    } else {
-      /* run over all the contiguous dead objects */
-      HeapWord* end = q;
-      do {
-        /* prefetch beyond end */
-        Prefetch::write(end, interval);
-        end += oop(end)->size();
-      } while (end < t && (!oop(end)->is_gc_marked()));
-
-      /* see if we might want to pretend this object is alive so that
-       * we don't have to compact quite as often.
-       */
-      if (allowed_deadspace > 0 && q == compact_top) {
-        size_t sz = pointer_delta(end, q);
-        if (insert_deadspace(allowed_deadspace, q, sz)) {
-          size_t compaction_max_size = pointer_delta(compact_end, compact_top);
-
-          // This should only happen if a space in the young gen overflows the
-          // old gen. If that should happen, we null out the start_array, because
-          // the young spaces are not covered by one.
-          while (sz > compaction_max_size) {
-            // First record the last compact_top
-            dest->set_compaction_top(compact_top);
-
-            // Advance to the next compaction decorator
-            advance_destination_decorator();
-            dest = destination_decorator();
-
-            // Update compaction info
-            start_array = dest->start_array();
-            compact_top = dest->compaction_top();
-            compact_end = dest->space()->end();
-            assert(compact_top == dest->space()->bottom(), "Advanced to space already in use");
-            assert(compact_end > compact_top, "Must always be space remaining");
-            compaction_max_size =
-              pointer_delta(compact_end, compact_top);
-          }
-
-          // store the forwarding pointer into the mark word
-          if (q != compact_top) {
-            oop(q)->forward_to(oop(compact_top));
-            assert(oop(q)->is_gc_marked(), "encoding the pointer should preserve the mark");
-          } else {
-            // if the object isn't moving we can just set the mark to the default
-            // mark and handle it specially later on.
-            oop(q)->init_mark_raw();
-            assert(oop(q)->forwardee() == NULL, "should be forwarded to NULL");
-          }
-
-          // Update object start array
-          if (start_array) {
-            start_array->allocate_block(compact_top);
-          }
-
-          compact_top += sz;
-          assert(compact_top <= dest->space()->end(),
-            "Exceeding space in destination");
-
-          q = end;
-          end_of_live = end;
-          continue;
-        }
-      }
-
-      // q is a pointer to a dead object. Use this dead memory to store a pointer to the next live object.
-      (*(HeapWord**)q) = end;
-
-      /* see if this is the first dead region. */
-      if (q < first_dead) {
-        first_dead = q;
-      }
-
-      /* move on to the next object */
-      q = end;
-    }
-  }
-
-  assert(q == t, "just checking");
-  _end_of_live = end_of_live;
-  if (end_of_live < first_dead) {
-    first_dead = end_of_live;
-  }
-  _first_dead = first_dead;
-
-  // Update compaction top
-  dest->set_compaction_top(compact_top);
-}
-
-bool PSMarkSweepDecorator::insert_deadspace(size_t& allowed_deadspace_words,
-                                            HeapWord* q, size_t deadlength) {
-  if (allowed_deadspace_words >= deadlength) {
-    allowed_deadspace_words -= deadlength;
-    CollectedHeap::fill_with_object(q, deadlength);
-    oop(q)->set_mark_raw(oop(q)->mark_raw().set_marked());
-    assert((int) deadlength == oop(q)->size(), "bad filler object size");
-    // Recall that we required "q == compaction_top".
-    return true;
-  } else {
-    allowed_deadspace_words = 0;
-    return false;
-  }
-}
-
-void PSMarkSweepDecorator::adjust_pointers() {
-  // adjust all the interior pointers to point at the new locations of objects
-  // Used by MarkSweep::mark_sweep_phase3()
-
-  HeapWord* q = space()->bottom();
-  HeapWord* t = _end_of_live;  // Established by "prepare_for_compaction".
-
-  assert(_first_dead <= _end_of_live, "Stands to reason, no?");
-
-  if (q < t && _first_dead > q &&
-      !oop(q)->is_gc_marked()) {
-    // we have a chunk of the space which hasn't moved and we've
-    // reinitialized the mark word during the previous pass, so we can't
-    // use is_gc_marked for the traversal.
-    HeapWord* end = _first_dead;
-
-    while (q < end) {
-      // point all the oops to the new location
-      size_t size = MarkSweep::adjust_pointers(oop(q));
-      q += size;
-    }
-
-    if (_first_dead == t) {
-      q = t;
-    } else {
-      // The first dead object should contain a pointer to the first live object
-      q = *(HeapWord**)_first_dead;
-    }
-  }
-  const intx interval = PrefetchScanIntervalInBytes;
-
-  debug_only(HeapWord* prev_q = NULL);
-  while (q < t) {
-    // prefetch beyond q
-    Prefetch::write(q, interval);
-    if (oop(q)->is_gc_marked()) {
-      // q is alive
-      // point all the oops to the new location
-      size_t size = MarkSweep::adjust_pointers(oop(q));
-      debug_only(prev_q = q);
-      q += size;
-    } else {
-      debug_only(prev_q = q);
-      // The first dead object is no longer an object. At that memory address,
-      // there is a pointer to the first live object that the previous phase found.
-      q = *(HeapWord**)q;
-      assert(q > prev_q, "we should be moving forward through memory, q: " PTR_FORMAT ", prev_q: " PTR_FORMAT, p2i(q), p2i(prev_q));
-    }
-  }
-
-  assert(q == t, "just checking");
-}
-
-void PSMarkSweepDecorator::compact(bool mangle_free_space ) {
-  // Copy all live objects to their new location
-  // Used by MarkSweep::mark_sweep_phase4()
-
-  HeapWord*       q = space()->bottom();
-  HeapWord* const t = _end_of_live;
-  debug_only(HeapWord* prev_q = NULL);
-
-  if (q < t && _first_dead > q &&
-      !oop(q)->is_gc_marked()) {
-#ifdef ASSERT
-    // we have a chunk of the space which hasn't moved and we've reinitialized the
-    // mark word during the previous pass, so we can't use is_gc_marked for the
-    // traversal.
-    HeapWord* const end = _first_dead;
-
-    while (q < end) {
-      size_t size = oop(q)->size();
-      assert(!oop(q)->is_gc_marked(), "should be unmarked (special dense prefix handling)");
-      debug_only(prev_q = q);
-      q += size;
-    }
-#endif
-
-    if (_first_dead == t) {
-      q = t;
-    } else {
-      // $$$ Funky
-      q = (HeapWord*) oop(_first_dead)->mark_raw().decode_pointer();
-    }
-  }
-
-  const intx scan_interval = PrefetchScanIntervalInBytes;
-  const intx copy_interval = PrefetchCopyIntervalInBytes;
-
-  while (q < t) {
-    if (!oop(q)->is_gc_marked()) {
-      // mark is pointer to next marked oop
-      debug_only(prev_q = q);
-      q = (HeapWord*) oop(q)->mark_raw().decode_pointer();
-      assert(q > prev_q, "we should be moving forward through memory");
-    } else {
-      // prefetch beyond q
-      Prefetch::read(q, scan_interval);
-
-      // size and destination
-      size_t size = oop(q)->size();
-      HeapWord* compaction_top = (HeapWord*)oop(q)->forwardee();
-
-      // prefetch beyond compaction_top
-      Prefetch::write(compaction_top, copy_interval);
-
-      // copy object and reinit its mark
-      assert(q != compaction_top, "everything in this pass should be moving");
-      Copy::aligned_conjoint_words(q, compaction_top, size);
-      oop(compaction_top)->init_mark_raw();
-      assert(oop(compaction_top)->klass() != NULL, "should have a class");
-
-      debug_only(prev_q = q);
-      q += size;
-    }
-  }
-
-  assert(compaction_top() >= space()->bottom() && compaction_top() <= space()->end(),
-         "should point inside space");
-  space()->set_top(compaction_top());
-
-  if (mangle_free_space) {
-    space()->mangle_unused_area();
-  }
-}