[turbofan] Introduce DeadValue and DeadEffect operators.

src/compiler/graph-visualizer.cc

 // Copyright 2013 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-visualizer.h"
 
 #include <sstream>
 #include <string>
 
 #include "src/code-stubs.h"
@@ skipping 238 matching lines @@
 void GraphVisualizer::PrintNode(Node* node, bool gray) {
   Node* control_cluster = GetControlCluster(node);
   if (control_cluster != NULL) {
     os_ << "  subgraph cluster_BasicBlock" << control_cluster->id() << " {\n";
   }
   os_ << "  ID" << SafeId(node) << " [\n";
 
   os_ << "    shape=\"record\"\n";
   switch (node->opcode()) {
     case IrOpcode::kEnd:
-    case IrOpcode::kDead:
+    case IrOpcode::kDeadControl:
     case IrOpcode::kStart:
       os_ << "    style=\"diagonals\"\n";
       break;
     case IrOpcode::kMerge:
     case IrOpcode::kIfTrue:
     case IrOpcode::kIfFalse:
     case IrOpcode::kLoop:
       os_ << "    style=\"rounded\"\n";
       break;
     default:
@@ skipping 552 matching lines @@
         os << "#" << SafeId(i) << ":" << SafeMnemonic(i);
       }
       os << ")" << std::endl;
     }
   }
   return os;
 }
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8