--- a/src/hotspot/share/classfile/stringTable.cpp	Mon Aug 27 12:45:31 2018 -0700
+++ b/src/hotspot/share/classfile/stringTable.cpp	Mon Aug 27 17:20:29 2018 -0400
@@ -395,7 +395,7 @@
 };
 
 void StringTable::unlink_or_oops_do(BoolObjectClosure* is_alive, OopClosure* f,
-                                    int* processed, int* removed) {
+                                    size_t* processed, size_t* removed) {
   DoNothingClosure dnc;
   assert(is_alive != NULL, "No closure");
   StringTableIsAliveCounter stiac(is_alive);
@@ -409,10 +409,10 @@
   StringTable::the_table()->check_concurrent_work();
 
   if (processed != NULL) {
-    *processed = (int) stiac._count_total;
+    *processed = stiac._count_total;
   }
   if (removed != NULL) {
-    *removed = (int) stiac._count;
+    *removed = stiac._count;
   }
 }
 
@@ -423,7 +423,7 @@
 
 void StringTable::possibly_parallel_unlink(
    OopStorage::ParState<false, false>* _par_state_string, BoolObjectClosure* cl,
-   int* processed, int* removed)
+   size_t* processed, size_t* removed)
 {
   DoNothingClosure dnc;
   assert(cl != NULL, "No closure");
@@ -434,8 +434,8 @@
   // Accumulate the dead strings.
   the_table()->add_items_count_to_clean(stiac._count);
 
-  *processed = (int) stiac._count_total;
-  *removed = (int) stiac._count;
+  *processed = stiac._count_total;
+  *removed = stiac._count;
 }
 
 void StringTable::possibly_parallel_oops_do(

--- a/src/hotspot/share/classfile/stringTable.hpp	Mon Aug 27 12:45:31 2018 -0700
+++ b/src/hotspot/share/classfile/stringTable.hpp	Mon Aug 27 17:20:29 2018 -0400
@@ -136,7 +136,7 @@
     unlink_or_oops_do(cl);
   }
   static void unlink_or_oops_do(BoolObjectClosure* is_alive, OopClosure* f = NULL,
-                                int* processed = NULL, int* removed = NULL);
+                                size_t* processed = NULL, size_t* removed = NULL);
 
   // Serially invoke "f->do_oop" on the locations of all oops in the table.
   static void oops_do(OopClosure* f);
@@ -144,7 +144,7 @@
   // Possibly parallel versions of the above
   static void possibly_parallel_unlink(
      OopStorage::ParState<false /* concurrent */, false /* const*/>* par_state_string,
-     BoolObjectClosure* cl, int* processed, int* removed);
+     BoolObjectClosure* cl, size_t* processed, size_t* removed);
   static void possibly_parallel_oops_do(
      OopStorage::ParState<false /* concurrent */, false /* const*/>* par_state_string,
      OopClosure* f);

--- a/src/hotspot/share/gc/shared/parallelCleaning.cpp	Mon Aug 27 12:45:31 2018 -0700
+++ b/src/hotspot/share/gc/shared/parallelCleaning.cpp	Mon Aug 27 17:20:29 2018 -0400
@@ -54,8 +54,8 @@
 }
 
 void StringCleaningTask::work(uint worker_id) {
-  int strings_processed = 0;
-  int strings_removed = 0;
+  size_t strings_processed = 0;
+  size_t strings_removed = 0;
   if (_process_strings) {
     StringTable::possibly_parallel_unlink(&_par_state_string, _is_alive, &strings_processed, &strings_removed);
     Atomic::add(strings_processed, &_strings_processed);

--- a/src/hotspot/share/gc/shared/parallelCleaning.hpp	Mon Aug 27 12:45:31 2018 -0700
+++ b/src/hotspot/share/gc/shared/parallelCleaning.hpp	Mon Aug 27 17:20:29 2018 -0400
@@ -40,9 +40,9 @@
 
   int _initial_string_table_size;
 
-  bool  _process_strings;
-  int   _strings_processed;
-  int   _strings_removed;
+  bool            _process_strings;
+  volatile size_t _strings_processed;
+  volatile size_t _strings_removed;
 
 public:
   StringCleaningTask(BoolObjectClosure* is_alive, StringDedupUnlinkOrOopsDoClosure* dedup_closure, bool process_strings);
@@ -50,8 +50,8 @@
 
   void work(uint worker_id);
 
-  size_t strings_processed() const { return (size_t)_strings_processed; }
-  size_t strings_removed()   const { return (size_t)_strings_removed; }
+  size_t strings_processed() const { return _strings_processed; }
+  size_t strings_removed()   const { return _strings_removed; }
 };
 
 class CodeCacheUnloadingTask {