[turbofan] Don't switchify branches with hints.

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 186 matching lines @@
   cond->Kill();
   merge->Kill();
   return true;
 }
 
 
 bool ControlFlowOptimizer::TryBuildSwitch(Node* node) {
   DCHECK_EQ(IrOpcode::kBranch, node->opcode());
 
   Node* branch = node;
+  if (BranchHintOf(branch->op()) != BranchHint::kNone) return false;
   Node* cond = NodeProperties::GetValueInput(branch, 0);
   if (cond->opcode() != IrOpcode::kWord32Equal) return false;
   Int32BinopMatcher m(cond);
   Node* index = m.left().node();
   if (!m.right().HasValue()) return false;
   int32_t value = m.right().Value();
   ZoneSet<int32_t> values(zone());
   values.insert(value);
 
   Node* if_false;
   Node* if_true;
   while (true) {
     Node* control_projections[2];
     NodeProperties::CollectControlProjections(branch, control_projections, 2);
     if_true = control_projections[0];
     if_false = control_projections[1];
     DCHECK_EQ(IrOpcode::kIfTrue, if_true->opcode());
     DCHECK_EQ(IrOpcode::kIfFalse, if_false->opcode());
 
     auto it = if_false->uses().begin();
     if (it == if_false->uses().end()) break;
     Node* branch1 = *it++;
     if (branch1->opcode() != IrOpcode::kBranch) break;
+    if (BranchHintOf(branch1->op()) != BranchHint::kNone) break;
     if (it != if_false->uses().end()) break;
     Node* cond1 = branch1->InputAt(0);
     if (cond1->opcode() != IrOpcode::kWord32Equal) break;
     Int32BinopMatcher m1(cond1);
     if (m1.left().node() != index) break;
     if (!m1.right().HasValue()) break;
     int32_t value1 = m1.right().Value();
     if (values.find(value1) != values.end()) break;
     DCHECK_NE(value, value1);
 
@@ skipping 42 matching lines @@
 Graph* ControlFlowOptimizer::graph() const { return jsgraph()->graph(); }
 
 
 MachineOperatorBuilder* ControlFlowOptimizer::machine() const {
   return jsgraph()->machine();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8