[turbofan] Remove unused word32 truncation case for CheckFloat64Hole.

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 2682 matching lines @@
       }
       case IrOpcode::kCheckFloat64Hole: {
         Type* const input_type = TypeOf(node->InputAt(0));
         if (input_type->Is(Type::Number())) {
           VisitNoop(node, truncation);
         } else {
           CheckFloat64HoleMode mode = CheckFloat64HoleModeOf(node->op());
           switch (mode) {
             case CheckFloat64HoleMode::kAllowReturnHole:
               if (truncation.IsUnused()) return VisitUnused(node);
-              if (truncation.IsUsedAsWord32()) {
-                VisitUnop(node, UseInfo::TruncatingWord32(),
-                          MachineRepresentation::kWord32);
-                if (lower()) DeferReplacement(node, node->InputAt(0));
-              } else if (truncation.IsUsedAsFloat64()) {
+              if (truncation.IsUsedAsFloat64()) {
                 VisitUnop(node, UseInfo::TruncatingFloat64(),
                           MachineRepresentation::kFloat64);
                 if (lower()) DeferReplacement(node, node->InputAt(0));
               } else {
                 VisitUnop(
                     node,
                     UseInfo(MachineRepresentation::kFloat64, Truncation::Any()),
                     MachineRepresentation::kFloat64, Type::Number());
               }
               break;
@@ skipping 961 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