Upgrade V8 to version 4.9.385.28
https://chromium.googlesource.com/v8/v8/+/4.9.385.28
FPIIM-449
Change-Id: I4b2e74289d4bf3667f2f3dc8aa2e541f63e26eb4
diff --git a/src/compiler/graph-trimmer.cc b/src/compiler/graph-trimmer.cc
new file mode 100644
index 0000000..5fae425
--- /dev/null
+++ b/src/compiler/graph-trimmer.cc
@@ -0,0 +1,48 @@
+// Copyright 2015 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/compiler/graph-trimmer.h"
+
+#include "src/compiler/graph.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+GraphTrimmer::GraphTrimmer(Zone* zone, Graph* graph)
+ : graph_(graph), is_live_(graph, 2), live_(zone) {
+ live_.reserve(graph->NodeCount());
+}
+
+
+GraphTrimmer::~GraphTrimmer() {}
+
+
+void GraphTrimmer::TrimGraph() {
+ // Mark end node as live.
+ MarkAsLive(graph()->end());
+ // Compute transitive closure of live nodes.
+ for (size_t i = 0; i < live_.size(); ++i) {
+ for (Node* const input : live_[i]->inputs()) MarkAsLive(input);
+ }
+ // Remove dead->live edges.
+ for (Node* const live : live_) {
+ DCHECK(IsLive(live));
+ for (Edge edge : live->use_edges()) {
+ Node* const user = edge.from();
+ if (!IsLive(user)) {
+ if (FLAG_trace_turbo_reduction) {
+ OFStream os(stdout);
+ os << "DeadLink: " << *user << "(" << edge.index() << ") -> " << *live
+ << std::endl;
+ }
+ edge.UpdateTo(nullptr);
+ }
+ }
+ }
+}
+
+} // namespace compiler
+} // namespace internal
+} // namespace v8