1 files changed, 94 insertions, 0 deletions
diff --git a/deps/v8/src/heap/stress-scavenge-observer.cc b/deps/v8/src/heap/stress-scavenge-observer.cc
new file mode 100644
index 0000000000..c9f169ae45
--- /dev/null
+++ b/deps/v8/src/heap/stress-scavenge-observer.cc
@@ -0,0 +1,94 @@
+// Copyright 2017 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/heap/stress-scavenge-observer.h"
+
+#include "src/base/utils/random-number-generator.h"
+#include "src/heap/heap-inl.h"
+#include "src/heap/spaces.h"
+#include "src/isolate.h"
+
+namespace v8 {
+namespace internal {
+
+// TODO(majeski): meaningful step_size
+StressScavengeObserver::StressScavengeObserver(Heap& heap)
+    : AllocationObserver(64),
+      heap_(heap),
+      has_requested_gc_(false),
+      max_new_space_size_reached_(0.0) {
+  limit_percentage_ = NextLimit();
+
+  if (FLAG_trace_stress_scavenge && !FLAG_fuzzer_gc_analysis) {
+    heap_.isolate()->PrintWithTimestamp(
+        "[StressScavenge] %d%% is the new limit\n", limit_percentage_);
+  }
+}
+
+void StressScavengeObserver::Step(int bytes_allocated, Address soon_object,
+                                  size_t size) {
+  if (has_requested_gc_ || heap_.new_space()->Capacity() == 0) {
+    return;
+  }
+
+  double current_percent =
+      heap_.new_space()->Size() * 100.0 / heap_.new_space()->Capacity();
+
+  if (FLAG_trace_stress_scavenge) {
+    heap_.isolate()->PrintWithTimestamp(
+        "[Scavenge] %.2lf%% of the new space capacity reached\n",
+        current_percent);
+  }
+
+  if (FLAG_fuzzer_gc_analysis) {
+    max_new_space_size_reached_ =
+        std::max(max_new_space_size_reached_, current_percent);
+    return;
+  }
+
+  if (static_cast<int>(current_percent) >= limit_percentage_) {
+    if (FLAG_trace_stress_scavenge) {
+      heap_.isolate()->PrintWithTimestamp("[Scavenge] GC requested\n");
+    }
+
+    has_requested_gc_ = true;
+    heap_.isolate()->stack_guard()->RequestGC();
+  }
+}
+
+bool StressScavengeObserver::HasRequestedGC() const {
+  return has_requested_gc_;
+}
+
+void StressScavengeObserver::RequestedGCDone() {
+  double current_percent =
+      heap_.new_space()->Size() * 100.0 / heap_.new_space()->Capacity();
+  limit_percentage_ = NextLimit(static_cast<int>(current_percent));
+
+  if (FLAG_trace_stress_scavenge) {
+    heap_.isolate()->PrintWithTimestamp(
+        "[Scavenge] %.2lf%% of the new space capacity reached\n",
+        current_percent);
+    heap_.isolate()->PrintWithTimestamp("[Scavenge] %d%% is the new limit\n",
+                                        limit_percentage_);
+  }
+
+  has_requested_gc_ = false;
+}
+
+double StressScavengeObserver::MaxNewSpaceSizeReached() const {
+  return max_new_space_size_reached_;
+}
+
+int StressScavengeObserver::NextLimit(int min) {
+  int max = FLAG_stress_scavenge;
+  if (min >= max) {
+    return max;
+  }
+
+  return min + heap_.isolate()->fuzzer_rng()->NextInt(max - min + 1);
+}
+
+}  // namespace internal
+}  // namespace v8