--- a/src/share/vm/gc_implementation/g1/heapRegion.cpp	Tue Apr 07 11:20:51 2015 +0200
+++ b/src/share/vm/gc_implementation/g1/heapRegion.cpp	Tue Apr 07 14:58:49 2015 +0200
@@ -28,11 +28,15 @@
 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
 #include "gc_implementation/g1/heapRegion.inline.hpp"
+#include "gc_implementation/g1/heapRegionBounds.inline.hpp"
 #include "gc_implementation/g1/heapRegionRemSet.hpp"
-#include "gc_implementation/g1/heapRegionSeq.inline.hpp"
+#include "gc_implementation/g1/heapRegionManager.inline.hpp"
+#include "gc_implementation/shared/liveRange.hpp"
 #include "memory/genOopClosures.inline.hpp"
 #include "memory/iterator.hpp"
+#include "memory/space.inline.hpp"
 #include "oops/oop.inline.hpp"
+#include "runtime/orderAccess.inline.hpp"
 
 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
 
@@ -46,7 +50,7 @@
                                  HeapRegion* hr, ExtendedOopClosure* cl,
                                  CardTableModRefBS::PrecisionStyle precision,
                                  FilterKind fk) :
-  ContiguousSpaceDCTOC(hr, cl, precision, NULL),
+  DirtyCardToOopClosure(hr, cl, precision, NULL),
   _hr(hr), _fk(fk), _g1(g1) { }
 
 FilterOutOfRegionClosure::FilterOutOfRegionClosure(HeapRegion* r,
@@ -58,7 +62,7 @@
                                HeapRegion* hr,
                                HeapWord* cur, HeapWord* top) {
   oop cur_oop = oop(cur);
-  int oop_size = cur_oop->size();
+  size_t oop_size = hr->block_size(cur);
   HeapWord* next_obj = cur + oop_size;
   while (next_obj < top) {
     // Keep filtering the remembered set.
@@ -69,25 +73,24 @@
     }
     cur = next_obj;
     cur_oop = oop(cur);
-    oop_size = cur_oop->size();
+    oop_size = hr->block_size(cur);
     next_obj = cur + oop_size;
   }
   return cur;
 }
 
-void HeapRegionDCTOC::walk_mem_region_with_cl(MemRegion mr,
-                                              HeapWord* bottom,
-                                              HeapWord* top,
-                                              ExtendedOopClosure* cl) {
+void HeapRegionDCTOC::walk_mem_region(MemRegion mr,
+                                      HeapWord* bottom,
+                                      HeapWord* top) {
   G1CollectedHeap* g1h = _g1;
-  int oop_size;
+  size_t oop_size;
   ExtendedOopClosure* cl2 = NULL;
 
-  FilterIntoCSClosure intoCSFilt(this, g1h, cl);
-  FilterOutOfRegionClosure outOfRegionFilt(_hr, cl);
+  FilterIntoCSClosure intoCSFilt(this, g1h, _cl);
+  FilterOutOfRegionClosure outOfRegionFilt(_hr, _cl);
 
   switch (_fk) {
-  case NoFilterKind:          cl2 = cl; break;
+  case NoFilterKind:          cl2 = _cl; break;
   case IntoCSFilterKind:      cl2 = &intoCSFilt; break;
   case OutOfRegionFilterKind: cl2 = &outOfRegionFilt; break;
   default:                    ShouldNotReachHere();
@@ -100,7 +103,7 @@
   if (!g1h->is_obj_dead(oop(bottom), _hr)) {
     oop_size = oop(bottom)->oop_iterate(cl2, mr);
   } else {
-    oop_size = oop(bottom)->size();
+    oop_size = _hr->block_size(bottom);
   }
 
   bottom += oop_size;
@@ -109,17 +112,17 @@
     // We replicate the loop below for several kinds of possible filters.
     switch (_fk) {
     case NoFilterKind:
-      bottom = walk_mem_region_loop(cl, g1h, _hr, bottom, top);
+      bottom = walk_mem_region_loop(_cl, g1h, _hr, bottom, top);
       break;
 
     case IntoCSFilterKind: {
-      FilterIntoCSClosure filt(this, g1h, cl);
+      FilterIntoCSClosure filt(this, g1h, _cl);
       bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top);
       break;
     }
 
     case OutOfRegionFilterKind: {
-      FilterOutOfRegionClosure filt(_hr, cl);
+      FilterOutOfRegionClosure filt(_hr, _cl);
       bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top);
       break;
     }
@@ -135,32 +138,16 @@
   }
 }
 
-// Minimum region size; we won't go lower than that.
-// We might want to decrease this in the future, to deal with small
-// heaps a bit more efficiently.
-#define MIN_REGION_SIZE  (      1024 * 1024 )
-
-// Maximum region size; we don't go higher than that. There's a good
-// reason for having an upper bound. We don't want regions to get too
-// large, otherwise cleanup's effectiveness would decrease as there
-// will be fewer opportunities to find totally empty regions after
-// marking.
-#define MAX_REGION_SIZE  ( 32 * 1024 * 1024 )
-
-// The automatic region size calculation will try to have around this
-// many regions in the heap (based on the min heap size).
-#define TARGET_REGION_NUMBER          2048
-
 size_t HeapRegion::max_region_size() {
-  return (size_t)MAX_REGION_SIZE;
+  return HeapRegionBounds::max_size();
 }
 
 void HeapRegion::setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size) {
   uintx region_size = G1HeapRegionSize;
   if (FLAG_IS_DEFAULT(G1HeapRegionSize)) {
     size_t average_heap_size = (initial_heap_size + max_heap_size) / 2;
-    region_size = MAX2(average_heap_size / TARGET_REGION_NUMBER,
-                       (uintx) MIN_REGION_SIZE);
+    region_size = MAX2(average_heap_size / HeapRegionBounds::target_number(),
+                       (uintx) HeapRegionBounds::min_size());
   }
 
   int region_size_log = log2_long((jlong) region_size);
@@ -170,10 +157,10 @@
   region_size = ((uintx)1 << region_size_log);
 
   // Now make sure that we don't go over or under our limits.
-  if (region_size < MIN_REGION_SIZE) {
-    region_size = MIN_REGION_SIZE;
-  } else if (region_size > MAX_REGION_SIZE) {
-    region_size = MAX_REGION_SIZE;
+  if (region_size < HeapRegionBounds::min_size()) {
+    region_size = HeapRegionBounds::min_size();
+  } else if (region_size > HeapRegionBounds::max_size()) {
+    region_size = HeapRegionBounds::max_size();
   }
 
   // And recalculate the log.
@@ -208,8 +195,6 @@
 }
 
 void HeapRegion::hr_clear(bool par, bool clear_space, bool locked) {
-  assert(_humongous_type == NotHumongous,
-         "we should have already filtered out humongous regions");
   assert(_humongous_start_region == NULL,
          "we should have already filtered out humongous regions");
   assert(_end == _orig_end,
@@ -217,9 +202,10 @@
 
   _in_collection_set = false;
 
+  set_allocation_context(AllocationContext::system());
   set_young_index_in_cset(-1);
   uninstall_surv_rate_group();
-  set_young_type(NotYoung);
+  set_free();
   reset_pre_dummy_top();
 
   if (!par) {
@@ -270,7 +256,7 @@
   assert(top() == bottom(), "should be empty");
   assert(bottom() <= new_top && new_top <= new_end, "pre-condition");
 
-  _humongous_type = StartsHumongous;
+  _type.set_starts_humongous();
   _humongous_start_region = this;
 
   set_end(new_end);
@@ -284,11 +270,11 @@
   assert(top() == bottom(), "should be empty");
   assert(first_hr->startsHumongous(), "pre-condition");
 
-  _humongous_type = ContinuesHumongous;
+  _type.set_continues_humongous();
   _humongous_start_region = first_hr;
 }
 
-void HeapRegion::set_notHumongous() {
+void HeapRegion::clear_humongous() {
   assert(isHumongous(), "pre-condition");
 
   if (startsHumongous()) {
@@ -304,7 +290,6 @@
   }
 
   assert(capacity() == HeapRegion::GrainBytes, "pre-condition");
-  _humongous_type = NotHumongous;
   _humongous_start_region = NULL;
 }
 
@@ -319,46 +304,19 @@
   return false;
 }
 
-HeapWord* HeapRegion::next_block_start_careful(HeapWord* addr) {
-  HeapWord* low = addr;
-  HeapWord* high = end();
-  while (low < high) {
-    size_t diff = pointer_delta(high, low);
-    // Must add one below to bias toward the high amount.  Otherwise, if
-  // "high" were at the desired value, and "low" were one less, we
-    // would not converge on "high".  This is not symmetric, because
-    // we set "high" to a block start, which might be the right one,
-    // which we don't do for "low".
-    HeapWord* middle = low + (diff+1)/2;
-    if (middle == high) return high;
-    HeapWord* mid_bs = block_start_careful(middle);
-    if (mid_bs < addr) {
-      low = middle;
-    } else {
-      high = mid_bs;
-    }
-  }
-  assert(low == high && low >= addr, "Didn't work.");
-  return low;
-}
-
-#ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
-#pragma warning( disable:4355 ) // 'this' : used in base member initializer list
-#endif // _MSC_VER
-
-
-HeapRegion::HeapRegion(uint hrs_index,
+HeapRegion::HeapRegion(uint hrm_index,
                        G1BlockOffsetSharedArray* sharedOffsetArray,
                        MemRegion mr) :
     G1OffsetTableContigSpace(sharedOffsetArray, mr),
-    _hrs_index(hrs_index),
-    _humongous_type(NotHumongous), _humongous_start_region(NULL),
+    _hrm_index(hrm_index),
+    _allocation_context(AllocationContext::system()),
+    _humongous_start_region(NULL),
     _in_collection_set(false),
     _next_in_special_set(NULL), _orig_end(NULL),
     _claimed(InitialClaimValue), _evacuation_failed(false),
     _prev_marked_bytes(0), _next_marked_bytes(0), _gc_efficiency(0.0),
-    _young_type(NotYoung), _next_young_region(NULL),
-    _next_dirty_cards_region(NULL), _next(NULL), _prev(NULL), _pending_removal(false),
+    _next_young_region(NULL),
+    _next_dirty_cards_region(NULL), _next(NULL), _prev(NULL),
 #ifdef ASSERT
     _containing_set(NULL),
 #endif // ASSERT
@@ -367,55 +325,24 @@
     _predicted_bytes_to_copy(0)
 {
   _rem_set = new HeapRegionRemSet(sharedOffsetArray, this);
+  assert(HeapRegionRemSet::num_par_rem_sets() > 0, "Invariant.");
+
+  initialize(mr);
+}
+
+void HeapRegion::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
+  assert(_rem_set->is_empty(), "Remembered set must be empty");
+
+  G1OffsetTableContigSpace::initialize(mr, clear_space, mangle_space);
+
   _orig_end = mr.end();
-  // Note that initialize() will set the start of the unmarked area of the
-  // region.
   hr_clear(false /*par*/, false /*clear_space*/);
   set_top(bottom());
-  set_saved_mark();
-
-  assert(HeapRegionRemSet::num_par_rem_sets() > 0, "Invariant.");
+  record_top_and_timestamp();
 }
 
 CompactibleSpace* HeapRegion::next_compaction_space() const {
-  // We're not using an iterator given that it will wrap around when
-  // it reaches the last region and this is not what we want here.
-  G1CollectedHeap* g1h = G1CollectedHeap::heap();
-  uint index = hrs_index() + 1;
-  while (index < g1h->n_regions()) {
-    HeapRegion* hr = g1h->region_at(index);
-    if (!hr->isHumongous()) {
-      return hr;
-    }
-    index += 1;
-  }
-  return NULL;
-}
-
-void HeapRegion::save_marks() {
-  set_saved_mark();
-}
-
-void HeapRegion::oops_in_mr_iterate(MemRegion mr, ExtendedOopClosure* cl) {
-  HeapWord* p = mr.start();
-  HeapWord* e = mr.end();
-  oop obj;
-  while (p < e) {
-    obj = oop(p);
-    p += obj->oop_iterate(cl);
-  }
-  assert(p == e, "bad memregion: doesn't end on obj boundary");
-}
-
-#define HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN(OopClosureType, nv_suffix) \
-void HeapRegion::oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl) { \
-  ContiguousSpace::oop_since_save_marks_iterate##nv_suffix(cl);              \
-}
-SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN)
-
-
-void HeapRegion::oop_before_save_marks_iterate(ExtendedOopClosure* cl) {
-  oops_in_mr_iterate(MemRegion(bottom(), saved_mark_word()), cl);
+  return G1CollectedHeap::heap()->next_compaction_region(this);
 }
 
 void HeapRegion::note_self_forwarding_removal_start(bool during_initial_mark,
@@ -423,7 +350,6 @@
   // We always recreate the prev marking info and we'll explicitly
   // mark all objects we find to be self-forwarded on the prev
   // bitmap. So all objects need to be below PTAMS.
-  _prev_top_at_mark_start = top();
   _prev_marked_bytes = 0;
 
   if (during_initial_mark) {
@@ -447,6 +373,7 @@
   assert(0 <= marked_bytes && marked_bytes <= used(),
          err_msg("marked: "SIZE_FORMAT" used: "SIZE_FORMAT,
                  marked_bytes, used()));
+  _prev_top_at_mark_start = top();
   _prev_marked_bytes = marked_bytes;
 }
 
@@ -477,7 +404,7 @@
     if (cl->abort()) return cur;
     // The check above must occur before the operation below, since an
     // abort might invalidate the "size" operation.
-    cur += obj->size();
+    cur += block_size(cur);
   }
   return NULL;
 }
@@ -549,7 +476,7 @@
       return cur;
     }
     // Otherwise...
-    next = (cur + obj->size());
+    next = cur + block_size(cur);
   }
 
   // If we finish the above loop...We have a parseable object that
@@ -557,10 +484,9 @@
   // inside or spans the entire region.
 
   assert(obj == oop(cur), "sanity");
-  assert(cur <= start &&
-         obj->klass_or_null() != NULL &&
-         (cur + obj->size()) > start,
-         "Loop postcondition");
+  assert(cur <= start, "Loop postcondition");
+  assert(obj->klass_or_null() != NULL, "Loop postcondition");
+  assert((cur + block_size(cur)) > start, "Loop postcondition");
 
   if (!g1h->is_obj_dead(obj)) {
     obj->oop_iterate(cl, mr);
@@ -574,7 +500,7 @@
     };
 
     // Otherwise:
-    next = (cur + obj->size());
+    next = cur + block_size(cur);
 
     if (!g1h->is_obj_dead(obj)) {
       if (next < end || !obj->is_objArray()) {
@@ -600,21 +526,17 @@
   hrrs->add_strong_code_root(nm);
 }
 
+void HeapRegion::add_strong_code_root_locked(nmethod* nm) {
+  assert_locked_or_safepoint(CodeCache_lock);
+  HeapRegionRemSet* hrrs = rem_set();
+  hrrs->add_strong_code_root_locked(nm);
+}
+
 void HeapRegion::remove_strong_code_root(nmethod* nm) {
   HeapRegionRemSet* hrrs = rem_set();
   hrrs->remove_strong_code_root(nm);
 }
 
-void HeapRegion::migrate_strong_code_roots() {
-  assert(in_collection_set(), "only collection set regions");
-  assert(!isHumongous(),
-          err_msg("humongous region "HR_FORMAT" should not have been added to collection set",
-                  HR_FORMAT_PARAMS(this)));
-
-  HeapRegionRemSet* hrrs = rem_set();
-  hrrs->migrate_strong_code_roots();
-}
-
 void HeapRegion::strong_code_roots_do(CodeBlobClosure* blk) const {
   HeapRegionRemSet* hrrs = rem_set();
   hrrs->strong_code_roots_do(blk);
@@ -750,26 +672,12 @@
 
 void HeapRegion::print() const { print_on(gclog_or_tty); }
 void HeapRegion::print_on(outputStream* st) const {
-  if (isHumongous()) {
-    if (startsHumongous())
-      st->print(" HS");
-    else
-      st->print(" HC");
-  } else {
-    st->print("   ");
-  }
+  st->print("AC%4u", allocation_context());
+  st->print(" %2s", get_short_type_str());
   if (in_collection_set())
     st->print(" CS");
   else
     st->print("   ");
-  if (is_young())
-    st->print(is_survivor() ? " SU" : " Y ");
-  else
-    st->print("   ");
-  if (is_empty())
-    st->print(" F");
-  else
-    st->print("  ");
   st->print(" TS %5d", _gc_time_stamp);
   st->print(" PTAMS "PTR_FORMAT" NTAMS "PTR_FORMAT,
             prev_top_at_mark_start(), next_top_at_mark_start());
@@ -929,10 +837,11 @@
   size_t object_num = 0;
   while (p < top()) {
     oop obj = oop(p);
-    size_t obj_size = obj->size();
+    size_t obj_size = block_size(p);
     object_num += 1;
 
-    if (is_humongous != g1->isHumongous(obj_size)) {
+    if (is_humongous != g1->isHumongous(obj_size) &&
+        !g1->is_obj_dead(obj, this)) { // Dead objects may have bigger block_size since they span several objects.
       gclog_or_tty->print_cr("obj "PTR_FORMAT" is of %shumongous size ("
                              SIZE_FORMAT" words) in a %shumongous region",
                              p, g1->isHumongous(obj_size) ? "" : "non-",
@@ -942,8 +851,10 @@
     }
 
     // If it returns false, verify_for_object() will output the
-    // appropriate messasge.
-    if (do_bot_verify && !_offsets.verify_for_object(p, obj_size)) {
+    // appropriate message.
+    if (do_bot_verify &&
+        !g1->is_obj_dead(obj, this) &&
+        !_offsets.verify_for_object(p, obj_size)) {
       *failures = true;
       return;
     }
@@ -951,7 +862,10 @@
     if (!g1->is_obj_dead_cond(obj, this, vo)) {
       if (obj->is_oop()) {
         Klass* klass = obj->klass();
-        if (!klass->is_metaspace_object()) {
+        bool is_metaspace_object = Metaspace::contains(klass) ||
+                                   (vo == VerifyOption_G1UsePrevMarking &&
+                                   ClassLoaderDataGraph::unload_list_contains(klass));
+        if (!is_metaspace_object) {
           gclog_or_tty->print_cr("klass "PTR_FORMAT" of object "PTR_FORMAT" "
                                  "not metadata", klass, (void *)obj);
           *failures = true;
@@ -1065,9 +979,10 @@
 // away eventually.
 
 void G1OffsetTableContigSpace::clear(bool mangle_space) {
-  ContiguousSpace::clear(mangle_space);
-  _offsets.zero_bottom_entry();
-  _offsets.initialize_threshold();
+  set_top(bottom());
+  set_saved_mark_word(bottom());
+  CompactibleSpace::clear(mangle_space);
+  reset_bot();
 }
 
 void G1OffsetTableContigSpace::set_bottom(HeapWord* new_bottom) {
@@ -1100,13 +1015,16 @@
 HeapWord* G1OffsetTableContigSpace::saved_mark_word() const {
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   assert( _gc_time_stamp <= g1h->get_gc_time_stamp(), "invariant" );
-  if (_gc_time_stamp < g1h->get_gc_time_stamp())
-    return top();
-  else
-    return ContiguousSpace::saved_mark_word();
+  HeapWord* local_top = top();
+  OrderAccess::loadload();
+  if (_gc_time_stamp < g1h->get_gc_time_stamp()) {
+    return local_top;
+  } else {
+    return Space::saved_mark_word();
+  }
 }
 
-void G1OffsetTableContigSpace::set_saved_mark() {
+void G1OffsetTableContigSpace::record_top_and_timestamp() {
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   unsigned curr_gc_time_stamp = g1h->get_gc_time_stamp();
 
@@ -1118,7 +1036,7 @@
     // of region. If it does so after _gc_time_stamp = ..., then it
     // will pick up the right saved_mark_word() as the high water mark
     // of the region. Either way, the behaviour will be correct.
-    ContiguousSpace::set_saved_mark();
+    Space::set_saved_mark_word(top());
     OrderAccess::storestore();
     _gc_time_stamp = curr_gc_time_stamp;
     // No need to do another barrier to flush the writes above. If
@@ -1129,6 +1047,26 @@
   }
 }
 
+void G1OffsetTableContigSpace::safe_object_iterate(ObjectClosure* blk) {
+  object_iterate(blk);
+}
+
+void G1OffsetTableContigSpace::object_iterate(ObjectClosure* blk) {
+  HeapWord* p = bottom();
+  while (p < top()) {
+    if (block_is_obj(p)) {
+      blk->do_object(oop(p));
+    }
+    p += block_size(p);
+  }
+}
+
+#define block_is_always_obj(q) true
+void G1OffsetTableContigSpace::prepare_for_compaction(CompactPoint* cp) {
+  SCAN_AND_FORWARD(cp, top, block_is_always_obj, block_size);
+}
+#undef block_is_always_obj
+
 G1OffsetTableContigSpace::
 G1OffsetTableContigSpace(G1BlockOffsetSharedArray* sharedOffsetArray,
                          MemRegion mr) :
@@ -1137,8 +1075,11 @@
   _gc_time_stamp(0)
 {
   _offsets.set_space(this);
-  // false ==> we'll do the clearing if there's clearing to be done.
-  ContiguousSpace::initialize(mr, false, SpaceDecorator::Mangle);
-  _offsets.zero_bottom_entry();
-  _offsets.initialize_threshold();
 }
+
+void G1OffsetTableContigSpace::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
+  CompactibleSpace::initialize(mr, clear_space, mangle_space);
+  _top = bottom();
+  reset_bot();
+}
+