Reland of [heap] Simplify distribution of remaining memory during sweeping & compaction

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 966 matching lines @@
   accounting_stats_.Clear();
 }
 
 
 void PagedSpace::AddMemory(Address start, intptr_t size) {
   accounting_stats_.ExpandSpace(static_cast<int>(size));
   Free(start, static_cast<int>(size));
 }
 
 
-FreeSpace* PagedSpace::TryRemoveMemory(intptr_t size_in_bytes) {
-  FreeSpace* free_space = free_list()->TryRemoveMemory(size_in_bytes);
-  if (free_space != nullptr) {
-    accounting_stats_.DecreaseCapacity(free_space->size());
-  }
-  return free_space;
-}
-
-
-void PagedSpace::DivideUponCompactionSpaces(CompactionSpaceCollection** other,
-                                            int num, intptr_t limit) {
-  DCHECK_GT(num, 0);
-  DCHECK(other != nullptr);
-
-  if (limit == 0) limit = std::numeric_limits<intptr_t>::max();
-
-  EmptyAllocationInfo();
-
-  bool memory_available = true;
-  bool spaces_need_memory = true;
-  FreeSpace* node = nullptr;
-  CompactionSpace* current_space = nullptr;
-  // Iterate over spaces and memory as long as we have memory and there are
-  // spaces in need of some.
-  while (memory_available && spaces_need_memory) {
-    spaces_need_memory = false;
-    // Round-robin over all spaces.
-    for (int i = 0; i < num; i++) {
-      current_space = other[i]->Get(identity());
-      if (current_space->free_list()->Available() < limit) {
-        // Space has not reached its limit. Try to get some memory.
-        spaces_need_memory = true;
-        node = TryRemoveMemory(limit - current_space->free_list()->Available());
-        if (node != nullptr) {
-          CHECK(current_space->identity() == identity());
-          current_space->AddMemory(node->address(), node->size());
-        } else {
-          memory_available = false;
-          break;
-        }
-      }
-    }
-  }
-}
-
-
 void PagedSpace::RefillFreeList() {
   MarkCompactCollector* collector = heap()->mark_compact_collector();
   FreeList* free_list = nullptr;
   if (this == heap()->old_space()) {
     free_list = collector->free_list_old_space().get();
   } else if (this == heap()->code_space()) {
     free_list = collector->free_list_code_space().get();
   } else if (this == heap()->map_space()) {
     free_list = collector->free_list_map_space().get();
   } else {
@@ skipping 22 matching lines @@
   intptr_t refilled = 0;
   while (refilled < kCompactionMemoryWanted) {
     FreeSpace* node =
         free_list->TryRemoveMemory(kCompactionMemoryWanted - refilled);
     if (node == nullptr) return;
     refilled += node->size();
     AddMemory(node->address(), node->size());
   }
 }
 
-
 void PagedSpace::MoveOverFreeMemory(PagedSpace* other) {
   DCHECK(identity() == other->identity());
   // Destroy the linear allocation space of {other}. This is needed to
   //   (a) not waste the memory and
   //   (b) keep the rest of the chunk in an iterable state (filler is needed).
   other->EmptyAllocationInfo();
 
   // Move over the free list. Concatenate makes sure that the source free list
   // gets properly reset after moving over all nodes.
   intptr_t added = free_list_.Concatenate(other->free_list());
@@ skipping 2199 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8