[turbofan] Reorganize the pipeline around the 2nd scheduler approach.

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 <sstream>
 
 #include "src/base/adapters.h"
@@ skipping 753 matching lines @@
     EscapeAnalysisReducer escape_reducer(&graph_reducer, data->jsgraph(),
                                          &escape_analysis, temp_zone);
     escape_reducer.SetExistsVirtualAllocate(
         escape_analysis.ExistsVirtualAllocate());
     AddReducer(data, &graph_reducer, &escape_reducer);
     graph_reducer.ReduceGraph();
     escape_reducer.VerifyReplacement();
   }
 };
 
-
-struct SimplifiedLoweringPhase {
-  static const char* phase_name() { return "simplified lowering"; }
+struct RepresentationSelectionPhase {
+  static const char* phase_name() { return "representation selection"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     SimplifiedLowering lowering(data->jsgraph(), temp_zone,
                                 data->source_positions());
     lowering.LowerAllNodes();
+  }
+};
 
+struct EarlyOptimizationPhase {
+  static const char* phase_name() { return "early optimization"; }
+
+  void Run(PipelineData* data, Zone* temp_zone) {
     JSGraphReducer graph_reducer(data->jsgraph(), temp_zone);
+    JSGenericLowering generic_lowering(data->jsgraph());
     DeadCodeElimination dead_code_elimination(&graph_reducer, data->graph(),
                                               data->common());
     SimplifiedOperatorReducer simple_reducer(data->jsgraph());
     ValueNumberingReducer value_numbering(temp_zone);
     MachineOperatorReducer machine_reducer(data->jsgraph());
     CommonOperatorReducer common_reducer(&graph_reducer, data->graph(),
                                          data->common(), data->machine());
     AddReducer(data, &graph_reducer, &dead_code_elimination);
     AddReducer(data, &graph_reducer, &simple_reducer);
+    AddReducer(data, &graph_reducer, &generic_lowering);
     AddReducer(data, &graph_reducer, &value_numbering);
     AddReducer(data, &graph_reducer, &machine_reducer);
     AddReducer(data, &graph_reducer, &common_reducer);
     graph_reducer.ReduceGraph();
   }
 };
 
-
 struct ControlFlowOptimizationPhase {
   static const char* phase_name() { return "control flow optimization"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     ControlFlowOptimizer optimizer(data->graph(), data->common(),
                                    data->machine(), temp_zone);
     optimizer.Optimize();
   }
 };
 
@@ skipping 20 matching lines @@
     // Post-pass for wiring the control/effects
     // - connect allocating representation changes into the control&effect
     //   chains and lower them,
     // - get rid of the region markers,
     // - introduce effect phis and rewire effects to get SSA again.
     EffectControlLinearizer introducer(data->jsgraph(), schedule, temp_zone);
     introducer.Run();
   }
 };
 
-struct ChangeLoweringPhase {
-  static const char* phase_name() { return "change lowering"; }
+struct LateOptimizationPhase {
+  static const char* phase_name() { return "late optimization"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     JSGraphReducer graph_reducer(data->jsgraph(), temp_zone);
     DeadCodeElimination dead_code_elimination(&graph_reducer, data->graph(),
                                               data->common());
     SimplifiedOperatorReducer simple_reducer(data->jsgraph());
     ValueNumberingReducer value_numbering(temp_zone);
     ChangeLowering lowering(data->jsgraph());
     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, &dead_code_elimination);
     AddReducer(data, &graph_reducer, &simple_reducer);
     AddReducer(data, &graph_reducer, &value_numbering);
     AddReducer(data, &graph_reducer, &lowering);
     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"; }
   void Run(PipelineData* data, Zone* temp_zone) {
     GraphTrimmer trimmer(temp_zone, data->graph());
     NodeVector roots(temp_zone);
     data->jsgraph()->GetCachedNodes(&roots);
@@ skipping 21 matching lines @@
     // TODO(titzer): peel all loops? the N'th loop? Innermost loops?
     LoopTree* loop_tree = LoopFinder::BuildLoopTree(data->graph(), temp_zone);
     if (loop_tree != nullptr && loop_tree->outer_loops().size() > 0) {
       LoopPeeler::Peel(data->graph(), data->common(), loop_tree,
                        loop_tree->outer_loops()[0], temp_zone);
     }
   }
 };
 
 
-struct GenericLoweringPhase {
-  static const char* phase_name() { return "generic lowering"; }
-
-  void Run(PipelineData* data, Zone* temp_zone) {
-    JSGraphReducer graph_reducer(data->jsgraph(), temp_zone);
-    DeadCodeElimination dead_code_elimination(&graph_reducer, data->graph(),
-                                              data->common());
-    CommonOperatorReducer common_reducer(&graph_reducer, data->graph(),
-                                         data->common(), data->machine());
-    JSGenericLowering generic_lowering(data->jsgraph());
-    SelectLowering select_lowering(data->jsgraph()->graph(),
-                                   data->jsgraph()->common());
-    TailCallOptimization tco(data->common(), data->graph());
-    AddReducer(data, &graph_reducer, &dead_code_elimination);
-    AddReducer(data, &graph_reducer, &common_reducer);
-    AddReducer(data, &graph_reducer, &generic_lowering);
-    AddReducer(data, &graph_reducer, &select_lowering);
-    AddReducer(data, &graph_reducer, &tco);
-    graph_reducer.ReduceGraph();
-  }
-};
-
-
 struct ComputeSchedulePhase {
   static const char* phase_name() { return "scheduling"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     Schedule* schedule = Scheduler::ComputeSchedule(
         temp_zone, data->graph(), data->info()->is_splitting_enabled()
                                       ? Scheduler::kSplitNodes
                                       : Scheduler::kNoFlags);
     if (FLAG_turbo_verify) ScheduleVerifier::Run(schedule);
     data->set_schedule(schedule);
@@ skipping 343 matching lines @@
   if (FLAG_turbo_stress_loop_peeling) {
     Run<StressLoopPeelingPhase>();
     RunPrintAndVerify("Loop peeled");
   }
 
   if (FLAG_experimental_turbo_escape) {
     Run<EscapeAnalysisPhase>();
     RunPrintAndVerify("Escape Analysed");
   }
 
-  // Lower simplified operators and insert changes.
-  Run<SimplifiedLoweringPhase>();
-  RunPrintAndVerify("Lowered simplified");
+  // Select representations.
+  Run<RepresentationSelectionPhase>();
+  RunPrintAndVerify("Representations selected");
+
+  // Run early optimization pass.
+  Run<EarlyOptimizationPhase>();
+  RunPrintAndVerify("Early optimized");
 
   if (info()->is_effect_scheduling_enabled()) {
     // TODO(jarin) Run value numbering for the representation changes.
     Run<EffectControlLinearizationPhase>();
     RunPrintAndVerify("Effect and control linearized");
   }
 
   Run<BranchEliminationPhase>();
   RunPrintAndVerify("Branch conditions eliminated");
 
   // Optimize control flow.
   if (FLAG_turbo_cf_optimization) {
     Run<ControlFlowOptimizationPhase>();
     RunPrintAndVerify("Control flow optimized");
   }
 
   // Lower changes that have been inserted before.
-  Run<ChangeLoweringPhase>();
+  Run<LateOptimizationPhase>();
   // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
-  RunPrintAndVerify("Lowered changes", true);
-
-  // Lower any remaining generic JSOperators.
-  Run<GenericLoweringPhase>();
-  // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
-  RunPrintAndVerify("Lowered generic", true);
+  RunPrintAndVerify("Late optimized", true);
 
   Run<LateGraphTrimmingPhase>();
   // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
   RunPrintAndVerify("Late trimmed", true);
 
   BeginPhaseKind("block building");
 
   data.source_positions()->RemoveDecorator();
 
   // Kill the Typer and thereby uninstall the decorator (if any).
@@ skipping 282 matching lines @@
   }
 
   data->DeleteRegisterAllocationZone();
 }
 
 Isolate* Pipeline::isolate() const { return info()->isolate(); }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8