1 /*
   2  * Copyright (c) 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 #include "precompiled.hpp"
  26 #include "gc/shared/markBitMap.inline.hpp"
  27 #include "memory/universe.hpp"
  28 #include "memory/virtualspace.hpp"
  29 
  30 void MarkBitMap::print_on_error(outputStream* st, const char* prefix) const {
  31   _bm.print_on_error(st, prefix);
  32 }
  33 
  34 size_t MarkBitMap::compute_size(size_t heap_size) {
  35   return ReservedSpace::allocation_align_size_up(heap_size / mark_distance());
  36 }
  37 
  38 size_t MarkBitMap::mark_distance() {
  39   return MinObjAlignmentInBytes * BitsPerByte;
  40 }
  41 
  42 void MarkBitMap::initialize(MemRegion heap, MemRegion storage) {
  43   _covered = heap;
  44 
  45   _bm = BitMapView((BitMap::bm_word_t*) storage.start(), _covered.word_size() >> _shifter);
  46 }
  47 
  48 void MarkBitMap::do_clear(MemRegion mr, bool large) {
  49   MemRegion intersection = mr.intersection(_covered);
  50   assert(!intersection.is_empty(),
  51          "Given range from " PTR_FORMAT " to " PTR_FORMAT " is completely outside the heap",
  52          p2i(mr.start()), p2i(mr.end()));
  53   // convert address range into offset range
  54   size_t beg = addr_to_offset(intersection.start());
  55   size_t end = addr_to_offset(intersection.end());
  56   if (large) {
  57     _bm.clear_large_range(beg, end);
  58   } else {
  59     _bm.clear_range(beg, end);
  60   }
  61 }
  62 
  63 #ifdef ASSERT
  64 void MarkBitMap::check_mark(HeapWord* addr) {
  65   assert(Universe::heap()->is_in(addr),
  66          "Trying to access bitmap " PTR_FORMAT " for address " PTR_FORMAT " not in the heap.",
  67          p2i(this), p2i(addr));
  68 }
  69 #endif