[turbofan] Introduce DeadValue and DeadEffect operators.

src/compiler/typer.cc

 // Copyright 2014 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/base/flags.h"
 #include "src/bootstrapper.h"
 #include "src/compiler/graph-reducer.h"
 #include "src/compiler/js-operator.h"
 #include "src/compiler/node.h"
 #include "src/compiler/node-properties.h"
@@ skipping 235 matching lines @@
       COMMON_OP_LIST(DECLARE_CASE)
       SIMPLIFIED_OP_LIST(DECLARE_CASE)
       MACHINE_OP_LIST(DECLARE_CASE)
       JS_SIMPLE_UNOP_LIST(DECLARE_CASE)
       JS_OBJECT_OP_LIST(DECLARE_CASE)
       JS_CONTEXT_OP_LIST(DECLARE_CASE)
       JS_OTHER_OP_LIST(DECLARE_CASE)
 #undef DECLARE_CASE
 
 #define DECLARE_CASE(x) case IrOpcode::k##x:
-      DECLARE_CASE(Dead)
       DECLARE_CASE(Loop)
       DECLARE_CASE(Branch)
       DECLARE_CASE(IfTrue)
       DECLARE_CASE(IfFalse)
       DECLARE_CASE(IfSuccess)
       DECLARE_CASE(Switch)
       DECLARE_CASE(IfValue)
       DECLARE_CASE(IfDefault)
       DECLARE_CASE(Merge)
       DECLARE_CASE(Deoptimize)
       DECLARE_CASE(Return)
       DECLARE_CASE(TailCall)
       DECLARE_CASE(Terminate)
       DECLARE_CASE(OsrNormalEntry)
       DECLARE_CASE(OsrLoopEntry)
+      DECLARE_CASE(DeadControl)
       DECLARE_CASE(Throw)
       DECLARE_CASE(End)
 #undef DECLARE_CASE
       break;
     }
     return NoChange();
   }
 
   Bounds TypeNode(Node* node) {
     switch (node->opcode()) {
 #define DECLARE_CASE(x) \
       case IrOpcode::k##x: return TypeBinaryOp(node, x##Typer);
       JS_SIMPLE_BINOP_LIST(DECLARE_CASE)
 #undef DECLARE_CASE
 
 #define DECLARE_CASE(x) case IrOpcode::k##x: return Type##x(node);
       DECLARE_CASE(Start)
       DECLARE_CASE(IfException)
       // VALUE_OP_LIST without JS_SIMPLE_BINOP_LIST:
       COMMON_OP_LIST(DECLARE_CASE)
       SIMPLIFIED_OP_LIST(DECLARE_CASE)
       MACHINE_OP_LIST(DECLARE_CASE)
       JS_SIMPLE_UNOP_LIST(DECLARE_CASE)
       JS_OBJECT_OP_LIST(DECLARE_CASE)
       JS_CONTEXT_OP_LIST(DECLARE_CASE)
       JS_OTHER_OP_LIST(DECLARE_CASE)
 #undef DECLARE_CASE
 
 #define DECLARE_CASE(x) case IrOpcode::k##x:
-      DECLARE_CASE(Dead)
       DECLARE_CASE(Loop)
       DECLARE_CASE(Branch)
       DECLARE_CASE(IfTrue)
       DECLARE_CASE(IfFalse)
       DECLARE_CASE(IfSuccess)
       DECLARE_CASE(Switch)
       DECLARE_CASE(IfValue)
       DECLARE_CASE(IfDefault)
       DECLARE_CASE(Merge)
       DECLARE_CASE(Deoptimize)
       DECLARE_CASE(Return)
       DECLARE_CASE(TailCall)
       DECLARE_CASE(Terminate)
       DECLARE_CASE(OsrNormalEntry)
       DECLARE_CASE(OsrLoopEntry)
+      DECLARE_CASE(DeadControl)
       DECLARE_CASE(Throw)
       DECLARE_CASE(End)
 #undef DECLARE_CASE
       break;
     }
     UNREACHABLE();
     return Bounds();
   }
 
   Type* TypeConstant(Handle<Object> value);
@@ skipping 408 matching lines @@
   UNREACHABLE();
   return Bounds();
 }
 
 
 Bounds Typer::Visitor::TypeFinish(Node* node) {
   return Operand(node, 0);
 }
 
 
+Bounds Typer::Visitor::TypeDeadValue(Node* node) {
+  return Bounds(Type::None(zone()), Type::Any(zone()));
+}
+
+
+Bounds Typer::Visitor::TypeDeadEffect(Node* node) {
+  UNREACHABLE();
+  return Bounds();
+}
+
+
 Bounds Typer::Visitor::TypeFrameState(Node* node) {
   // TODO(rossberg): Ideally FrameState wouldn't have a value output.
   return Bounds(Type::None(zone()), Type::Internal(zone()));
 }
 
 
 Bounds Typer::Visitor::TypeStateValues(Node* node) {
   return Bounds(Type::None(zone()), Type::Internal(zone()));
 }
 
@@ skipping 1663 matching lines @@
       TYPED_ARRAYS(TYPED_ARRAY_CASE)
 #undef TYPED_ARRAY_CASE
     }
   }
   return Type::Constant(value, zone());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8