Revert of [turbofan] Introduce CheckUnless.

src/compiler/simplified-lowering.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/compiler/simplified-lowering.h"
 
 #include <limits>
 
 #include "src/address-map.h"
 #include "src/base/bits.h"
@@ skipping 1174 matching lines @@
         return VisitLeaf(node, MachineRepresentation::kFloat32);
       case IrOpcode::kFloat64Constant:
         return VisitLeaf(node, MachineRepresentation::kFloat64);
       case IrOpcode::kExternalConstant:
         return VisitLeaf(node, MachineType::PointerRepresentation());
       case IrOpcode::kNumberConstant:
         return VisitLeaf(node, MachineRepresentation::kTagged);
       case IrOpcode::kHeapConstant:
         return VisitLeaf(node, MachineRepresentation::kTagged);
 
-      case IrOpcode::kCheckIf:
-      case IrOpcode::kCheckUnless:
-        ProcessInput(node, 0, UseInfo::Bool());
-        ProcessRemainingInputs(node, 1);
-        return;
       case IrOpcode::kDeoptimizeIf:
       case IrOpcode::kDeoptimizeUnless:
         ProcessInput(node, 0, UseInfo::Bool());
         ProcessInput(node, 1, UseInfo::AnyTagged());
         ProcessRemainingInputs(node, 2);
         return;
       case IrOpcode::kBranch:
         ProcessInput(node, 0, UseInfo::Bool());
         EnqueueInput(node, NodeProperties::FirstControlIndex(node));
         return;
@@ skipping 1823 matching lines @@
         isolate(), graph()->zone(), callable.descriptor(), 0, flags,
         Operator::kNoProperties);
     to_number_operator_.set(common()->Call(desc));
   }
   return to_number_operator_.get();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8