Do nothing when sweeping is in progress.

test/unittests/heap/gc-idle-time-handler-unittest.cc

 // Copyright 2014 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 <limits>
 
 #include "src/heap/gc-idle-time-handler.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace v8 {
@@ skipping 310 matching lines @@
   heap_state.incremental_marking_stopped = true;
   heap_state.can_start_incremental_marking = false;
   heap_state.sweeping_in_progress = true;
   heap_state.sweeping_completed = false;
   double idle_time_ms = 10.0;
   GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
   EXPECT_EQ(DO_NOTHING, action.type);
 }
 
 
+TEST_F(GCIdleTimeHandlerTest, NoIncrementalMarkingWhileSweeping) {
+  GCIdleTimeHandler::HeapState heap_state = DefaultHeapState();
+  heap_state.incremental_marking_stopped = false;
+  heap_state.can_start_incremental_marking = false;
+  heap_state.sweeping_in_progress = true;
+  heap_state.sweeping_completed = false;
+  double idle_time_ms = 10.0;
+  GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
+  EXPECT_EQ(DO_NOTHING, action.type);
+}
+
+
 TEST_F(GCIdleTimeHandlerTest, StopEventually1) {
   GCIdleTimeHandler::HeapState heap_state = DefaultHeapState();
   heap_state.incremental_marking_stopped = true;
   heap_state.can_start_incremental_marking = false;
   size_t speed = heap_state.mark_compact_speed_in_bytes_per_ms;
   double idle_time_ms =
       static_cast<double>(heap_state.size_of_objects / speed + 1);
   for (int i = 0; i < GCIdleTimeHandler::kMaxMarkCompactsInIdleRound; i++) {
     GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
     EXPECT_EQ(DO_FULL_GC, action.type);
@@ skipping 119 matching lines @@
   // Emulate mutator work.
   for (int i = 0; i < GCIdleTimeHandler::kIdleScavengeThreshold; i++) {
     handler()->NotifyScavenge();
   }
   action = handler()->Compute(0, heap_state);
   EXPECT_EQ(DO_NOTHING, action.type);
 }
 
 }  // namespace internal
 }  // namespace v8