8327477: Parallel: Remove _data_location and _highest_ref in Parallel…

…CompactData

Reviewed-by: gli, tschatzl

src/hotspot/share/gc/parallel/psParallelCompact.cpp

@@ -255,11 +255,11 @@ print_generic_summary_region(size_t i, const ParallelCompactData::RegionData* c)
   ParallelCompactData& sd = PSParallelCompact::summary_data();
   size_t dci = c->destination() ? sd.addr_to_region_idx(c->destination()) : 0;
   log_develop_trace(gc, compaction)(
-      REGION_IDX_FORMAT " " PTR_FORMAT " "
+      REGION_IDX_FORMAT " "
       REGION_IDX_FORMAT " " PTR_FORMAT " "
       REGION_DATA_FORMAT " " REGION_DATA_FORMAT " "
       REGION_DATA_FORMAT " " REGION_IDX_FORMAT " %d",
-      i, p2i(c->data_location()), dci, p2i(c->destination()),
+      i, dci, p2i(c->destination()),
       c->partial_obj_size(), c->live_obj_size(),
       c->data_size(), c->source_region(), c->destination_count());
 
@@ -540,7 +540,6 @@ ParallelCompactData::summarize_dense_prefix(HeapWord* beg, HeapWord* end)
     _region_data[cur_region].set_destination(addr);
     _region_data[cur_region].set_destination_count(0);
     _region_data[cur_region].set_source_region(cur_region);
-    _region_data[cur_region].set_data_location(addr);
 
     // Update live_obj_size so the region appears completely full.
     size_t live_size = RegionSize - _region_data[cur_region].partial_obj_size();
@@ -734,7 +733,6 @@ bool ParallelCompactData::summarize(SplitInfo& split_info,
       }
 
       _region_data[cur_region].set_destination_count(destination_count);
-      _region_data[cur_region].set_data_location(region_to_addr(cur_region));
       dest_addr += words;
     }
 

src/hotspot/share/gc/parallel/psParallelCompact.hpp

@@ -279,9 +279,6 @@ class ParallelCompactData
     // Number of times the block table was filled.
     DEBUG_ONLY(inline size_t blocks_filled_count() const;)
 
-    // The location of the java heap data that corresponds to this region.
-    inline HeapWord* data_location() const;
-
     // Whether this region is available to be claimed, has been claimed, or has
     // been completed.
     //
@@ -304,7 +301,7 @@ class ParallelCompactData
 
     inline void set_destination_count(uint count);
     inline void set_live_obj_size(size_t words);
-    inline void set_data_location(HeapWord* addr);
+
     inline void set_completed();
     inline bool claim_unsafe();
 
@@ -363,11 +360,6 @@ class ParallelCompactData
 
 #ifdef ASSERT
     size_t               _blocks_filled_count;   // Number of block table fills.
-
-    // These enable optimizations that are only partially implemented.  Use
-    // debug builds to prevent the code fragments from breaking.
-    HeapWord*            _data_location;
-    HeapWord*            _highest_ref;
 #endif  // #ifdef ASSERT
 
 #ifdef ASSERT
@@ -538,17 +530,6 @@ inline void ParallelCompactData::RegionData::decrement_destination_count()
   Atomic::add(&_dc_and_los, dc_mask);
 }
 
-inline HeapWord* ParallelCompactData::RegionData::data_location() const
-{
-  DEBUG_ONLY(return _data_location;)
-  NOT_DEBUG(return nullptr;)
-}
-
-inline void ParallelCompactData::RegionData::set_data_location(HeapWord* addr)
-{
-  DEBUG_ONLY(_data_location = addr;)
-}
-
 inline void ParallelCompactData::RegionData::set_completed()
 {
   assert(claimed(), "must be claimed first");