[turbofan] Run checkpoint elimination early.

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 759 matching lines @@
 };
 
 
 struct InliningPhase {
   static const char* phase_name() { return "inlining"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     JSGraphReducer graph_reducer(data->jsgraph(), temp_zone);
     DeadCodeElimination dead_code_elimination(&graph_reducer, data->graph(),
                                               data->common());
+    CheckpointElimination checkpoint_elimination(&graph_reducer);
     CommonOperatorReducer common_reducer(&graph_reducer, data->graph(),
                                          data->common(), data->machine());
     JSCallReducer::Flags call_reducer_flags = JSCallReducer::kNoFlags;
     if (data->info()->is_deoptimization_enabled()) {
       call_reducer_flags |= JSCallReducer::kDeoptimizationEnabled;
     }
     JSCallReducer call_reducer(&graph_reducer, data->jsgraph(),
                                call_reducer_flags, data->native_context(),
                                data->info()->dependencies());
     JSContextSpecialization context_specialization(
@@ skipping 21 matching lines @@
         &graph_reducer, data->info()->is_inlining_enabled()
                             ? JSInliningHeuristic::kGeneralInlining
                             : JSInliningHeuristic::kRestrictedInlining,
         temp_zone, data->info(), data->jsgraph(), data->source_positions());
     JSIntrinsicLowering intrinsic_lowering(
         &graph_reducer, data->jsgraph(),
         data->info()->is_deoptimization_enabled()
             ? JSIntrinsicLowering::kDeoptimizationEnabled
             : JSIntrinsicLowering::kDeoptimizationDisabled);
     AddReducer(data, &graph_reducer, &dead_code_elimination);
+    AddReducer(data, &graph_reducer, &checkpoint_elimination);
     AddReducer(data, &graph_reducer, &common_reducer);
     if (data->info()->is_frame_specializing()) {
       AddReducer(data, &graph_reducer, &frame_specialization);
     }
     AddReducer(data, &graph_reducer, &native_context_specialization);
     AddReducer(data, &graph_reducer, &context_specialization);
     AddReducer(data, &graph_reducer, &intrinsic_lowering);
     AddReducer(data, &graph_reducer, &call_reducer);
     AddReducer(data, &graph_reducer, &inlining);
     graph_reducer.ReduceGraph();
@@ skipping 1183 matching lines @@
   data->DeleteRegisterAllocationZone();
 }
 
 CompilationInfo* PipelineImpl::info() const { return data_->info(); }
 
 Isolate* PipelineImpl::isolate() const { return info()->isolate(); }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8