src/share/vm/gc/g1/g1BlockOffsetTable.cpp

rev 12504 : 8173764: G1 BOT wrongly assumes that objects must always begin at the start of G1BlockOffsetTablePart
Reviewed-by:
rev 12505 : imported patch 8173764-rev-tschatzl
rev 12506 : [mq]: 8173764-rev-kbarret

*** 1,7 ****
  /*
!  * Copyright (c) 2001, 2016, 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.
--- 1,7 ----
  /*
!  * Copyright (c) 2001, 2017, 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.
*** 77,87 ****
  G1BlockOffsetTablePart::G1BlockOffsetTablePart(G1BlockOffsetTable* array, G1ContiguousSpace* gsp) :
    _bot(array),
    _space(gsp),
    _next_offset_threshold(NULL),
    _next_offset_index(0)
! { }
  
  // The arguments follow the normal convention of denoting
  // a right-open interval: [start, end)
  void G1BlockOffsetTablePart:: set_remainder_to_point_to_start(HeapWord* start, HeapWord* end) {
  
--- 77,89 ----
  G1BlockOffsetTablePart::G1BlockOffsetTablePart(G1BlockOffsetTable* array, G1ContiguousSpace* gsp) :
    _bot(array),
    _space(gsp),
    _next_offset_threshold(NULL),
    _next_offset_index(0)
! {
!   debug_only(_object_can_span = false;)
! }
  
  // The arguments follow the normal convention of denoting
  // a right-open interval: [start, end)
  void G1BlockOffsetTablePart:: set_remainder_to_point_to_start(HeapWord* start, HeapWord* end) {
  
*** 362,371 ****
--- 364,379 ----
                  p2i(_space->bottom()), p2i(backskip_address));
      }
    }
  }
  
+ #ifdef ASSERT
+ void G1BlockOffsetTablePart::set_object_can_span(bool can_span) {
+   _object_can_span = can_span;
+ }
+ #endif
+ 
  #ifndef PRODUCT
  void
  G1BlockOffsetTablePart::print_on(outputStream* out) {
    size_t from_index = _bot->index_for(_space->bottom());
    size_t to_index = _bot->index_for(_space->end());