[turbofan] Proper dead code elimination as regular reducer.

src/compiler/common-operator.h

Index: src/compiler/common-operator.h
diff --git a/src/compiler/common-operator.h b/src/compiler/common-operator.h
index af20b10a4b4c6f660fd0617d364a81539fd93f59..08553bceaa6ec7650d4ba96318c1c87f976f7a56 100644
--- a/src/compiler/common-operator.h
+++ b/src/compiler/common-operator.h
@@ -96,6 +96,7 @@ class CommonOperatorBuilder final : public ZoneObject {
  public:
   explicit CommonOperatorBuilder(Zone* zone);
 
+  const Operator* Dead();
   const Operator* End(size_t control_input_count);
   const Operator* Branch(BranchHint = BranchHint::kNone);
   const Operator* IfTrue();
@@ -110,10 +111,6 @@ class CommonOperatorBuilder final : public ZoneObject {
   const Operator* Return();
   const Operator* Terminate();
 
-  const Operator* DeadValue();
-  const Operator* DeadEffect();
-  const Operator* DeadControl();
-
   const Operator* Start(int num_formal_parameters);
   const Operator* Loop(int control_input_count);
   const Operator* Merge(int control_input_count);