Address problem of back to back old gen GC that happens when new gen GC promotions triggers old gen…

runtime/vm/heap.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/heap.h"
 
 #include "platform/assert.h"
 #include "platform/utils.h"
 #include "vm/flags.h"
 #include "vm/isolate.h"
@@ skipping 351 matching lines @@
     class_table->ResetCountersNew();
   } else {
     class_table->ResetCountersOld();
   }
 }
 
 
 void Heap::CollectNewSpaceGarbage(Thread* thread,
                                   ApiCallbacks api_callbacks,
                                   GCReason reason) {
+  ASSERT((reason == kNewSpace) || (reason == kFull));
   if (BeginNewSpaceGC(thread)) {
     bool invoke_api_callbacks = (api_callbacks == kInvokeApiCallbacks);
     RecordBeforeGC(kNew, reason);
     VMTagScope tagScope(thread, VMTag::kGCNewSpaceTagId);
     TIMELINE_FUNCTION_GC_DURATION(thread, "CollectNewGeneration");
     UpdateClassHeapStatsBeforeGC(kNew);
     new_space_.Scavenge(invoke_api_callbacks);
     isolate()->class_table()->UpdatePromoted();
     UpdatePretenurePolicy();
     RecordAfterGC(kNew);
     PrintStats();
     EndNewSpaceGC();
-    if (old_space_.NeedsGarbageCollection()) {
+    if ((reason == kNewSpace) && old_space_.NeedsGarbageCollection()) {
       // Old collections should call the API callbacks.
       CollectOldSpaceGarbage(thread, kInvokeApiCallbacks, kPromotion);
     }
   }
 }
 
 
 void Heap::CollectOldSpaceGarbage(Thread* thread,
                                   ApiCallbacks api_callbacks,
                                   GCReason reason) {
+  ASSERT((reason != kNewSpace));
   if (BeginOldSpaceGC(thread)) {
     bool invoke_api_callbacks = (api_callbacks == kInvokeApiCallbacks);
     RecordBeforeGC(kOld, reason);
     VMTagScope tagScope(thread, VMTag::kGCOldSpaceTagId);
     TIMELINE_FUNCTION_GC_DURATION(thread, "CollectOldGeneration");
     UpdateClassHeapStatsBeforeGC(kOld);
     old_space_.MarkSweep(invoke_api_callbacks);
     RecordAfterGC(kOld);
     PrintStats();
     EndOldSpaceGC();
@@ skipping 446 matching lines @@
   Dart::vm_isolate()->heap()->WriteProtect(false);
 }
 
 
 WritableVMIsolateScope::~WritableVMIsolateScope() {
   ASSERT(Dart::vm_isolate()->heap()->UsedInWords(Heap::kNew) == 0);
   Dart::vm_isolate()->heap()->WriteProtect(true);
 }
 
 }  // namespace dart