Concurrent/parallel precise sweeping.

src/spaces.h

 // 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.
 
 #ifndef V8_SPACES_H_
 #define V8_SPACES_H_
 
 #include "src/allocation.h"
 #include "src/base/atomicops.h"
 #include "src/base/platform/mutex.h"
@@ skipping 432 matching lines @@
   // are set to the value in "flags", the rest retain the current value
   // in flags_.
   void SetFlags(intptr_t flags, intptr_t mask) {
     flags_ = (flags_ & ~mask) | (flags & mask);
   }
 
   // Return all current flags.
   intptr_t GetFlags() { return flags_; }
 
 
-  // PARALLEL_SWEEPING_DONE - The page state when sweeping is complete or
-  // sweeping must not be performed on that page.
-  // PARALLEL_SWEEPING_FINALIZE - A sweeper thread is done sweeping this
-  // page and will not touch the page memory anymore.
-  // PARALLEL_SWEEPING_IN_PROGRESS - This page is currently swept by a
-  // sweeper thread.
-  // PARALLEL_SWEEPING_PENDING - This page is ready for parallel sweeping.
+  // SWEEPING_DONE - The page state when sweeping is complete or sweeping must
+  // not be performed on that page.
+  // SWEEPING_FINALIZE - A sweeper thread is done sweeping this page and will
+  // not touch the page memory anymore.
+  // SWEEPING_IN_PROGRESS - This page is currently swept by a sweeper thread.
+  // SWEEPING_PENDING - This page is ready for parallel sweeping.
   enum ParallelSweepingState {
-    PARALLEL_SWEEPING_DONE,
-    PARALLEL_SWEEPING_FINALIZE,
-    PARALLEL_SWEEPING_IN_PROGRESS,
-    PARALLEL_SWEEPING_PENDING
+    SWEEPING_DONE,
+    SWEEPING_FINALIZE,
+    SWEEPING_IN_PROGRESS,
+    SWEEPING_PENDING
   };
 
   ParallelSweepingState parallel_sweeping() {
     return static_cast<ParallelSweepingState>(
         base::Acquire_Load(&parallel_sweeping_));
   }
 
   void set_parallel_sweeping(ParallelSweepingState state) {
     base::Release_Store(&parallel_sweeping_, state);
   }
 
   bool TryParallelSweeping() {
     return base::Acquire_CompareAndSwap(
-               &parallel_sweeping_, PARALLEL_SWEEPING_PENDING,
-               PARALLEL_SWEEPING_IN_PROGRESS) == PARALLEL_SWEEPING_PENDING;
+        &parallel_sweeping_, SWEEPING_PENDING, SWEEPING_IN_PROGRESS) ==
+            SWEEPING_PENDING;
   }
 
   // Manage live byte count (count of bytes known to be live,
   // because they are marked black).
   void ResetLiveBytes() {
     if (FLAG_gc_verbose) {
       PrintF("ResetLiveBytes:%p:%x->0\n",
              static_cast<void*>(this), live_byte_count_);
     }
     live_byte_count_ = 0;
@@ skipping 1420 matching lines @@
 
   // Reports statistics for the space
   void ReportStatistics();
 
   // Report code object related statistics
   void CollectCodeStatistics();
   static void ReportCodeStatistics(Isolate* isolate);
   static void ResetCodeStatistics(Isolate* isolate);
 #endif
 
-  bool is_iterable() { return is_iterable_; }
-  void set_is_iterable(bool b) { is_iterable_ = b; }
+  bool swept_precisely() { return swept_precisely_; }
+  void set_swept_precisely(bool b) { swept_precisely_ = b; }
 
   // Evacuation candidates are swept by evacuator.  Needs to return a valid
   // result before _and_ after evacuation has finished.
   static bool ShouldBeSweptBySweeperThreads(Page* p) {
     return !p->IsEvacuationCandidate() &&
            !p->IsFlagSet(Page::RESCAN_ON_EVACUATION) &&
            !p->WasSweptPrecisely();
   }
 
   void IncrementUnsweptFreeBytes(intptr_t by) {
@@ skipping 63 matching lines @@
   // The dummy page that anchors the double linked list of pages.
   Page anchor_;
 
   // The space's free list.
   FreeList free_list_;
 
   // Normal allocation information.
   AllocationInfo allocation_info_;
 
   // This space was swept precisely, hence it is iterable.
-  bool is_iterable_;
+  bool swept_precisely_;
 
   // The number of free bytes which could be reclaimed by advancing the
   // concurrent sweeper threads.  This is only an estimation because concurrent
   // sweeping is done conservatively.
   intptr_t unswept_free_bytes_;
 
   // The sweeper threads iterate over the list of pointer and data space pages
   // and sweep these pages concurrently. They will stop sweeping after the
   // end_of_unswept_pages_ page.
   Page* end_of_unswept_pages_;
@@ skipping 1010 matching lines @@
   }
   // Must be small, since an iteration is used for lookup.
   static const int kMaxComments = 64;
 };
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_H_