[turbofan] Remove value numbering from late optimization pass.

src/compiler/pipeline.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/pipeline.h"
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <memory>
 #include <sstream>
 
@@ skipping 1115 matching lines @@
 
 struct LateOptimizationPhase {
   static const char* phase_name() { return "late optimization"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     JSGraphReducer graph_reducer(data->jsgraph(), temp_zone);
     BranchElimination branch_condition_elimination(&graph_reducer,
                                                    data->jsgraph(), temp_zone);
     DeadCodeElimination dead_code_elimination(&graph_reducer, data->graph(),
                                               data->common());
-    ValueNumberingReducer value_numbering(temp_zone, data->graph()->zone());
     MachineOperatorReducer machine_reducer(data->jsgraph());
     CommonOperatorReducer common_reducer(&graph_reducer, data->graph(),
                                          data->common(), data->machine());
     SelectLowering select_lowering(data->jsgraph()->graph(),
                                    data->jsgraph()->common());
     TailCallOptimization tco(data->common(), data->graph());
     AddReducer(data, &graph_reducer, &branch_condition_elimination);
     AddReducer(data, &graph_reducer, &dead_code_elimination);
-    AddReducer(data, &graph_reducer, &value_numbering);
     AddReducer(data, &graph_reducer, &machine_reducer);
     AddReducer(data, &graph_reducer, &common_reducer);
     AddReducer(data, &graph_reducer, &select_lowering);
     AddReducer(data, &graph_reducer, &tco);
     graph_reducer.ReduceGraph();
   }
 };
 
 struct EarlyGraphTrimmingPhase {
   static const char* phase_name() { return "early graph trimming"; }
@@ skipping 843 matching lines @@
   data->DeleteRegisterAllocationZone();
 }
 
 CompilationInfo* PipelineImpl::info() const { return data_->info(); }
 
 Isolate* PipelineImpl::isolate() const { return info()->isolate(); }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8