--- a/src/share/vm/gc_implementation/g1/heapRegion.cpp	Mon Nov 29 18:32:30 2010 +0100
+++ b/src/share/vm/gc_implementation/g1/heapRegion.cpp	Tue Nov 30 14:53:30 2010 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright 2001-2010 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright (c) 2001, 2010, 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
@@ -16,9 +16,9 @@
  * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
+ * 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.
  *
  */
 
@@ -290,7 +290,7 @@
   // Recalculate the region size to make sure it's a power of
   // 2. This means that region_size is the largest power of 2 that's
   // <= what we've calculated so far.
-  region_size = ((uintx)1) << region_size_log;
+  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) {
@@ -377,10 +377,26 @@
 }
 // </PREDICTION>
 
-void HeapRegion::set_startsHumongous() {
+void HeapRegion::set_startsHumongous(HeapWord* new_end) {
+  assert(end() == _orig_end,
+         "Should be normal before the humongous object allocation");
+  assert(top() == bottom(), "should be empty");
+
   _humongous_type = StartsHumongous;
   _humongous_start_region = this;
-  assert(end() == _orig_end, "Should be normal before alloc.");
+
+  set_end(new_end);
+  _offsets.set_for_starts_humongous(new_end);
+}
+
+void HeapRegion::set_continuesHumongous(HeapRegion* start) {
+  assert(end() == _orig_end,
+         "Should be normal before the humongous object allocation");
+  assert(top() == bottom(), "should be empty");
+  assert(start->startsHumongous(), "pre-condition");
+
+  _humongous_type = ContinuesHumongous;
+  _humongous_start_region = start;
 }
 
 bool HeapRegion::claimHeapRegion(jint claimValue) {
@@ -500,23 +516,6 @@
   return blk.result();
 }
 
-void HeapRegion::set_continuesHumongous(HeapRegion* start) {
-  // The order is important here.
-  start->add_continuingHumongousRegion(this);
-  _humongous_type = ContinuesHumongous;
-  _humongous_start_region = start;
-}
-
-void HeapRegion::add_continuingHumongousRegion(HeapRegion* cont) {
-  // Must join the blocks of the current H region seq with the block of the
-  // added region.
-  offsets()->join_blocks(bottom(), cont->bottom());
-  arrayOop obj = (arrayOop)(bottom());
-  obj->set_length((int) (obj->length() + cont->capacity()/jintSize));
-  set_end(cont->end());
-  set_top(cont->end());
-}
-
 void HeapRegion::save_marks() {
   set_saved_mark();
 }
@@ -554,11 +553,19 @@
 #endif
 
 void HeapRegion::set_zero_fill_state_work(ZeroFillState zfs) {
-  assert(top() == bottom() || zfs == Allocated,
-         "Region must be empty, or we must be setting it to allocated.");
   assert(ZF_mon->owned_by_self() ||
          Universe::heap()->is_gc_active(),
          "Must hold the lock or be a full GC to modify.");
+#ifdef ASSERT
+  if (top() != bottom() && zfs != Allocated) {
+    ResourceMark rm;
+    stringStream region_str;
+    print_on(&region_str);
+    assert(top() == bottom() || zfs == Allocated,
+           err_msg("Region must be empty, or we must be setting it to allocated. "
+                   "_zfs=%d, zfs=%d, region: %s", _zfs, zfs, region_str.as_string()));
+  }
+#endif
   _zfs = zfs;
 }
 
@@ -650,7 +657,8 @@
 HeapWord*
 HeapRegion::
 oops_on_card_seq_iterate_careful(MemRegion mr,
-                                     FilterOutOfRegionClosure* cl) {
+                                 FilterOutOfRegionClosure* cl,
+                                 bool filter_young) {
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
 
   // If we're within a stop-world GC, then we might look at a card in a
@@ -664,6 +672,18 @@
   if (mr.is_empty()) return NULL;
   // Otherwise, find the obj that extends onto mr.start().
 
+  // The intersection of the incoming mr (for the card) and the
+  // allocated part of the region is non-empty. This implies that
+  // we have actually allocated into this region. The code in
+  // G1CollectedHeap.cpp that allocates a new region sets the
+  // is_young tag on the region before allocating. Thus we
+  // safely know if this region is young.
+  if (is_young() && filter_young) {
+    return NULL;
+  }
+
+  assert(!is_young(), "check value of filter_young");
+
   // We used to use "block_start_careful" here.  But we're actually happy
   // to update the BOT while we do this...
   HeapWord* cur = block_start(mr.start());
@@ -769,8 +789,18 @@
   int objs = 0;
   int blocks = 0;
   VerifyLiveClosure vl_cl(g1, use_prev_marking);
+  bool is_humongous = isHumongous();
+  size_t object_num = 0;
   while (p < top()) {
     size_t size = oop(p)->size();
+    if (is_humongous != g1->isHumongous(size)) {
+      gclog_or_tty->print_cr("obj "PTR_FORMAT" is of %shumongous size ("
+                             SIZE_FORMAT" words) in a %shumongous region",
+                             p, g1->isHumongous(size) ? "" : "non-",
+                             size, is_humongous ? "" : "non-");
+       *failures = true;
+    }
+    object_num += 1;
     if (blocks == BLOCK_SAMPLE_INTERVAL) {
       HeapWord* res = block_start_const(p + (size/2));
       if (p != res) {
@@ -836,6 +866,13 @@
     }
   }
 
+  if (is_humongous && object_num > 1) {
+    gclog_or_tty->print_cr("region ["PTR_FORMAT","PTR_FORMAT"] is humongous "
+                           "but has "SIZE_FORMAT", objects",
+                           bottom(), end(), object_num);
+    *failures = true;
+  }
+
   if (p != top()) {
     gclog_or_tty->print_cr("end of last object "PTR_FORMAT" "
                            "does not match top "PTR_FORMAT, p, top());