--- old/src/hotspot/share/gc/cms/concurrentMarkSweepGeneration.cpp	2019-08-13 12:39:45.340144256 +0200
+++ new/src/hotspot/share/gc/cms/concurrentMarkSweepGeneration.cpp	2019-08-13 12:39:45.040139052 +0200
@@ -7779,7 +7779,7 @@
   const markWord proto = markWord::prototype();
   NOT_PRODUCT(ssize_t n = 0;)
   for (oop next; i > 0 && cur != NULL; cur = next, i--) {
-    next = oop((void*)cur->mark_raw().value());
+    next = oop(cur->mark_raw().to_pointer());
     cur->set_mark_raw(proto);   // until proven otherwise
     assert(oopDesc::is_oop(cur), "Should be an oop");
     bool res = stack->push(cur);
@@ -7863,8 +7863,8 @@
   size_t i = num;
   oop cur = prefix;
   // Walk down the first "num" objects, unless we reach the end.
-  for (; i > 1 && cur->mark_raw().value() != 0; cur = oop((void*)cur->mark_raw().value()), i--);
-  if (cur->mark_raw().value() == 0) {
+  for (; i > 1 && cur->mark_raw().to_pointer() != NULL; cur = oop(cur->mark_raw().to_pointer()), i--);
+  if (cur->mark_raw().to_pointer() == NULL) {
     // We have "num" or fewer elements in the list, so there
     // is nothing to return to the global list.
     // Write back the NULL in lieu of the BUSY we wrote
@@ -7874,9 +7874,9 @@
     }
   } else {
     // Chop off the suffix and return it to the global list.
-    assert(cur->mark_raw().value() != (uintptr_t)(void*)BUSY, "Error");
-    oop suffix_head = oop((void*)cur->mark_raw().value()); // suffix will be put back on global list
-    cur->set_mark_raw(markWord(0));           // break off suffix
+    assert(cur->mark_raw().to_pointer() != (void*)BUSY, "Error");
+    oop suffix_head = oop(cur->mark_raw().to_pointer()); // suffix will be put back on global list
+    cur->set_mark_raw(markWord::from_pointer(NULL));                      // break off suffix
     // It's possible that the list is still in the empty(busy) state
     // we left it in a short while ago; in that case we may be
     // able to place back the suffix without incurring the cost
@@ -7896,18 +7896,18 @@
       // Too bad, someone else sneaked in (at least) an element; we'll need
       // to do a splice. Find tail of suffix so we can prepend suffix to global
       // list.
-      for (cur = suffix_head; cur->mark_raw().value() != 0; cur = (oop)((void*)cur->mark_raw().value()));
+      for (cur = suffix_head; cur->mark_raw().to_pointer() != NULL; cur = (oop)(cur->mark_raw().to_pointer()));
       oop suffix_tail = cur;
-      assert(suffix_tail != NULL && suffix_tail->mark_raw().value() == 0,
+      assert(suffix_tail != NULL && suffix_tail->mark_raw().to_pointer() == NULL,
              "Tautology");
       observed_overflow_list = _overflow_list;
       do {
         cur_overflow_list = observed_overflow_list;
         if (cur_overflow_list != BUSY) {
           // Do the splice ...
-          suffix_tail->set_mark_raw(markWord((uintptr_t)(void*)cur_overflow_list));
+          suffix_tail->set_mark_raw(markWord::from_pointer((void*)cur_overflow_list));
         } else { // cur_overflow_list == BUSY
-          suffix_tail->set_mark_raw(markWord(0));
+          suffix_tail->set_mark_raw(markWord::from_pointer(NULL));
         }
         // ... and try to place spliced list back on overflow_list ...
         observed_overflow_list =
@@ -7923,7 +7923,7 @@
   oop next;
   NOT_PRODUCT(ssize_t n = 0;)
   for (cur = prefix; cur != NULL; cur = next) {
-    next = oop((void*)cur->mark_raw().value());
+    next = oop(cur->mark_raw().to_pointer());
     cur->set_mark_raw(proto);   // until proven otherwise
     assert(oopDesc::is_oop(cur), "Should be an oop");
     bool res = work_q->push(cur);
@@ -7956,9 +7956,9 @@
   do {
     cur_overflow_list = observed_overflow_list;
     if (cur_overflow_list != BUSY) {
-      p->set_mark_raw(markWord((uintptr_t)(void*)cur_overflow_list));
+      p->set_mark_raw(markWord::from_pointer((void*)cur_overflow_list));
     } else {
-      p->set_mark_raw(markWord(0));
+      p->set_mark_raw(markWord::from_pointer(NULL));
     }
     observed_overflow_list =
       Atomic::cmpxchg((oopDesc*)p, &_overflow_list, (oopDesc*)cur_overflow_list);