[turbofan] Fix ControlFlowOptimizer to also handle non-control nodes in the control chain.

src/compiler/control-flow-optimizer.cc

 // 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/control-flow-optimizer.h"
 
 #include "src/compiler/js-graph.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 
@@ skipping 28 matching lines @@
 
 void ControlFlowOptimizer::Enqueue(Node* node) {
   DCHECK_NOT_NULL(node);
   if (node->IsDead() || queued_.Get(node)) return;
   queued_.Set(node, true);
   queue_.push(node);
 }
 
 
 void ControlFlowOptimizer::VisitNode(Node* node) {
-  for (Node* use : node->uses()) {
-    if (NodeProperties::IsControl(use)) Enqueue(use);
+  for (Edge edge : node->use_edges()) {
+    if (NodeProperties::IsControlEdge(edge)) {
+      Enqueue(edge.from());
+    }
   }
 }
 
 
 void ControlFlowOptimizer::VisitBranch(Node* node) {
   DCHECK_EQ(IrOpcode::kBranch, node->opcode());
   if (TryBuildSwitch(node)) return;
   if (TryCloneBranch(node)) return;
   VisitNode(node);
 }
@@ skipping 190 matching lines @@
     value = value1;
     values.insert(value);
   }
 
   DCHECK_EQ(IrOpcode::kBranch, node->opcode());
   DCHECK_EQ(IrOpcode::kBranch, branch->opcode());
   DCHECK_EQ(IrOpcode::kIfTrue, if_true->opcode());
   DCHECK_EQ(IrOpcode::kIfFalse, if_false->opcode());
   if (branch == node) {
     DCHECK_EQ(1u, values.size());
-    Enqueue(if_true);
-    Enqueue(if_false);
-  } else {
-    DCHECK_LT(1u, values.size());
-    node->set_op(common()->Switch(values.size() + 1));
-    node->ReplaceInput(0, index);
-    if_true->set_op(common()->IfValue(value));
-    if_true->ReplaceInput(0, node);
-    Enqueue(if_true);
-    if_false->set_op(common()->IfDefault());
-    if_false->ReplaceInput(0, node);
-    Enqueue(if_false);
-    branch->RemoveAllInputs();
+    return false;
   }
+  DCHECK_LT(1u, values.size());
+  node->set_op(common()->Switch(values.size() + 1));
+  node->ReplaceInput(0, index);
+  if_true->set_op(common()->IfValue(value));
+  if_true->ReplaceInput(0, node);
+  Enqueue(if_true);
+  if_false->set_op(common()->IfDefault());
+  if_false->ReplaceInput(0, node);
+  Enqueue(if_false);
+  branch->RemoveAllInputs();
   return true;
 }
 
 
 CommonOperatorBuilder* ControlFlowOptimizer::common() const {
   return jsgraph()->common();
 }
 
 
 Graph* ControlFlowOptimizer::graph() const { return jsgraph()->graph(); }
 
 
 MachineOperatorBuilder* ControlFlowOptimizer::machine() const {
   return jsgraph()->machine();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8