[GC] Check for incremental marking when a GC is triggered on reaching the external allocation limit

src/api.cc

 // Copyright 2012 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/api.h"
 
 #include <string.h>  // For memcpy, strlen.
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
@@ skipping 6869 matching lines @@
   }
   ENTER_V8(internal_isolate);
   i::Handle<i::Object> result = internal_isolate->factory()->NewNumber(value);
   return Utils::IntegerToLocal(result);
 }
 
 
 void Isolate::CollectAllGarbage(const char* gc_reason) {
   i::Heap* heap = reinterpret_cast<i::Isolate*>(this)->heap();
   if (heap->incremental_marking()->IsStopped()) {
-    heap->StartIncrementalMarking(i::Heap::kNoGCFlags, kGCCallbackFlagForced,
-                                  gc_reason);
+    if (heap->incremental_marking()->CanBeActivated()) {
+      heap->StartIncrementalMarking(i::Heap::kNoGCFlags, kGCCallbackFlagForced,
+                                    gc_reason);
+    } else {
+      heap->CollectAllGarbage(i::Heap::kNoGCFlags, gc_reason,
+                              kGCCallbackFlagForced);
+    }
+  } else {
+    // Incremental marking is turned on an has already been started.
+
+    // TODO(mlippautz): Compute the time slice for incremental marking based on
+    // memory pressure.
+    double deadline = heap->MonotonicallyIncreasingTimeInMs() +
+                      i::FLAG_external_allocation_limit_incremental_time;
+    heap->AdvanceIncrementalMarking(
+        0, deadline, i::IncrementalMarking::StepActions(
+                         i::IncrementalMarking::GC_VIA_STACK_GUARD,
+                         i::IncrementalMarking::FORCE_MARKING,
+                         i::IncrementalMarking::FORCE_COMPLETION));
   }
-  // TODO(mlippautz): Compute the time slice for incremental marking based on
-  // memory pressure.
-  double deadline = heap->MonotonicallyIncreasingTimeInMs() +
-                    i::FLAG_external_allocation_limit_incremental_time;
-  heap->AdvanceIncrementalMarking(0, deadline,
-                                  i::IncrementalMarking::StepActions(
-                                      i::IncrementalMarking::GC_VIA_STACK_GUARD,
-                                      i::IncrementalMarking::FORCE_MARKING,
-                                      i::IncrementalMarking::FORCE_COMPLETION));
 }
 
 
 HeapProfiler* Isolate::GetHeapProfiler() {
   i::HeapProfiler* heap_profiler =
       reinterpret_cast<i::Isolate*>(this)->heap_profiler();
   return reinterpret_cast<HeapProfiler*>(heap_profiler);
 }
 
 
@@ skipping 1504 matching lines @@
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 }  // namespace internal
 }  // namespace v8