[heap] Introduce enum of garbage collection reasons.

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 494 matching lines @@
         isolate->factory()->NewFixedArray(num_templates, i::TENURED);
     for (int i = 0; i < num_templates; i++) {
       templates->set(i, *v8::Utils::OpenHandle(*data->templates_.Get(i)));
     }
     isolate->heap()->SetSerializedTemplates(*templates);
     data->templates_.Clear();
   }
 
   // If we don't do this then we end up with a stray root pointing at the
   // context even after we have disposed of the context.
-  isolate->heap()->CollectAllAvailableGarbage("mksnapshot");
+  isolate->heap()->CollectAllAvailableGarbage(
+      i::GarbageCollectionReason::kSnapshotCreator);
   isolate->heap()->CompactWeakFixedArrays();
 
   i::DisallowHeapAllocation no_gc_from_here_on;
 
   int num_contexts = static_cast<int>(data->contexts_.Size());
   i::List<i::Object*> contexts(num_contexts);
   for (int i = 0; i < num_contexts; i++) {
     i::HandleScope scope(isolate);
     i::Handle<i::Context> context =
         v8::Utils::OpenHandle(*data->contexts_.Get(i));
@@ skipping 6944 matching lines @@
   }
   ENTER_V8(internal_isolate);
   i::Handle<i::Object> result = internal_isolate->factory()->NewNumber(value);
   return Utils::IntegerToLocal(result);
 }
 
 
 void Isolate::ReportExternalAllocationLimitReached() {
   i::Heap* heap = reinterpret_cast<i::Isolate*>(this)->heap();
   if (heap->gc_state() != i::Heap::NOT_IN_GC) return;
-  heap->ReportExternalMemoryPressure(
-      "external memory allocation limit reached.");
+  heap->ReportExternalMemoryPressure();
 }
 
 
 HeapProfiler* Isolate::GetHeapProfiler() {
   i::HeapProfiler* heap_profiler =
       reinterpret_cast<i::Isolate*>(this)->heap_profiler();
   return reinterpret_cast<HeapProfiler*>(heap_profiler);
 }
 
 
@@ skipping 139 matching lines @@
 void Isolate::RequestInterrupt(InterruptCallback callback, void* data) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
   isolate->RequestInterrupt(callback, data);
 }
 
 
 void Isolate::RequestGarbageCollectionForTesting(GarbageCollectionType type) {
   CHECK(i::FLAG_expose_gc);
   if (type == kMinorGarbageCollection) {
     reinterpret_cast<i::Isolate*>(this)->heap()->CollectGarbage(
-        i::NEW_SPACE, "Isolate::RequestGarbageCollection",
+        i::NEW_SPACE, i::GarbageCollectionReason::kTesting,
         kGCCallbackFlagForced);
   } else {
     DCHECK_EQ(kFullGarbageCollection, type);
     reinterpret_cast<i::Isolate*>(this)->heap()->CollectAllGarbage(
         i::Heap::kAbortIncrementalMarkingMask,
-        "Isolate::RequestGarbageCollection", kGCCallbackFlagForced);
+        i::GarbageCollectionReason::kTesting, kGCCallbackFlagForced);
   }
 }
 
 
 Isolate* Isolate::GetCurrent() {
   i::Isolate* isolate = i::Isolate::Current();
   return reinterpret_cast<Isolate*>(isolate);
 }
 
 
@@ skipping 408 matching lines @@
   return isolate->heap()->IdleNotification(deadline_in_seconds);
 }
 
 
 void Isolate::LowMemoryNotification() {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
   {
     i::HistogramTimerScope idle_notification_scope(
         isolate->counters()->gc_low_memory_notification());
     TRACE_EVENT0("v8", "V8.GCLowMemoryNotification");
-    isolate->heap()->CollectAllAvailableGarbage("low memory notification");
+    isolate->heap()->CollectAllAvailableGarbage(
+        i::GarbageCollectionReason::kLowMemoryNotification);
   }
 }
 
 
 int Isolate::ContextDisposedNotification(bool dependant_context) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
   return isolate->heap()->NotifyContextDisposed(dependant_context);
 }
 
 
@@ skipping 1135 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