[not for landing, heap] Parallel compaction in main GC pause

src/heap/spaces.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/heap/spaces.h"
 
 #include "src/base/bits.h"
 #include "src/base/platform/platform.h"
 #include "src/full-codegen/full-codegen.h"
 #include "src/heap/slots-buffer.h"
@@ skipping 474 matching lines @@
   chunk->area_end_ = area_end;
   chunk->flags_ = 0;
   chunk->set_owner(owner);
   chunk->InitializeReservedMemory();
   chunk->slots_buffer_ = NULL;
   chunk->skip_list_ = NULL;
   chunk->write_barrier_counter_ = kWriteBarrierCounterGranularity;
   chunk->progress_bar_ = 0;
   chunk->high_water_mark_.SetValue(static_cast<intptr_t>(area_start - base));
   chunk->set_parallel_sweeping(SWEEPING_DONE);
+  chunk->parallel_compaction_.SetValue(kCompactingDone);
   chunk->mutex_ = NULL;
   chunk->available_in_small_free_list_ = 0;
   chunk->available_in_medium_free_list_ = 0;
   chunk->available_in_large_free_list_ = 0;
   chunk->available_in_huge_free_list_ = 0;
   chunk->non_available_small_blocks_ = 0;
   chunk->ResetLiveBytes();
   Bitmap::Clear(chunk);
   chunk->initialize_scan_on_scavenge(false);
   chunk->SetFlag(WAS_SWEPT);
@@ skipping 1746 matching lines @@
 intptr_t FreeList::Concatenate(FreeList* free_list) {
   intptr_t free_bytes = 0;
   free_bytes += small_list_.Concatenate(free_list->small_list());
   free_bytes += medium_list_.Concatenate(free_list->medium_list());
   free_bytes += large_list_.Concatenate(free_list->large_list());
   free_bytes += huge_list_.Concatenate(free_list->huge_list());
   return free_bytes;
 }
 
 
+void FreeList::Divide(FreeList** free_lists_to_fill, size_t num) {
+  DCHECK(num > 0);
+  int size = 0;
+  FreeSpace* space = nullptr;
+  size_t cnt = 0;
+  while ((space = small_list_.PickNodeFromList(&size)) != nullptr) {
+    free_lists_to_fill[cnt % num]->small_list_.Free(space, size);
+    cnt++;
+  }
+  while ((space = medium_list_.PickNodeFromList(&size)) != nullptr) {
+    free_lists_to_fill[cnt % num]->medium_list_.Free(space, size);
+    cnt++;
+  }
+  while ((space = large_list_.PickNodeFromList(&size)) != nullptr) {
+    free_lists_to_fill[cnt % num]->large_list_.Free(space, size);
+    cnt++;
+  }
+  while ((space = huge_list_.PickNodeFromList(&size)) != nullptr) {
+    free_lists_to_fill[cnt % num]->huge_list_.Free(space, size);
+    cnt++;
+  }
+}
+
+
 void FreeList::Reset() {
   small_list_.Reset();
   medium_list_.Reset();
   large_list_.Reset();
   huge_list_.Reset();
 }
 
 
 int FreeList::Free(Address start, int size_in_bytes) {
   if (size_in_bytes == 0) return 0;
@@ skipping 913 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8