Revert "[turbofan] Smartify the GraphReducer."

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/platform/elapsed-timer.h"
@@ skipping 366 matching lines @@
   }
 
   if (!pipeline_statistics.is_empty()) {
     pipeline_statistics->BeginPhaseKind("lowering");
   }
 
   if (info()->is_typing_enabled()) {
     {
       // Lower JSOperators where we can determine types.
       PhaseScope phase_scope(pipeline_statistics.get(), "typed lowering");
-      ZonePool::Scope zone_scope(data.zone_pool());
       SourcePositionTable::Scope pos(data.source_positions(),
                                      SourcePosition::Unknown());
       ValueNumberingReducer vn_reducer(data.graph_zone());
       JSTypedLowering lowering(data.jsgraph());
       SimplifiedOperatorReducer simple_reducer(data.jsgraph());
-      GraphReducer graph_reducer(data.graph(), zone_scope.zone());
+      GraphReducer graph_reducer(data.graph());
       graph_reducer.AddReducer(&vn_reducer);
       graph_reducer.AddReducer(&lowering);
       graph_reducer.AddReducer(&simple_reducer);
       graph_reducer.ReduceGraph();
 
       VerifyAndPrintGraph(data.graph(), "Lowered typed");
     }
     {
       // Lower simplified operators and insert changes.
       PhaseScope phase_scope(pipeline_statistics.get(), "simplified lowering");
-      ZonePool::Scope zone_scope(data.zone_pool());
       SourcePositionTable::Scope pos(data.source_positions(),
                                      SourcePosition::Unknown());
       SimplifiedLowering lowering(data.jsgraph());
       lowering.LowerAllNodes();
       ValueNumberingReducer vn_reducer(data.graph_zone());
       SimplifiedOperatorReducer simple_reducer(data.jsgraph());
-      GraphReducer graph_reducer(data.graph(), zone_scope.zone());
+      GraphReducer graph_reducer(data.graph());
       graph_reducer.AddReducer(&vn_reducer);
       graph_reducer.AddReducer(&simple_reducer);
       graph_reducer.ReduceGraph();
 
       VerifyAndPrintGraph(data.graph(), "Lowered simplified");
     }
     {
       // Lower changes that have been inserted before.
       PhaseScope phase_scope(pipeline_statistics.get(), "change lowering");
-      ZonePool::Scope zone_scope(data.zone_pool());
       SourcePositionTable::Scope pos(data.source_positions(),
                                      SourcePosition::Unknown());
       Linkage linkage(data.graph_zone(), info());
       ValueNumberingReducer vn_reducer(data.graph_zone());
       SimplifiedOperatorReducer simple_reducer(data.jsgraph());
       ChangeLowering lowering(data.jsgraph(), &linkage);
       MachineOperatorReducer mach_reducer(data.jsgraph());
-      GraphReducer graph_reducer(data.graph(), zone_scope.zone());
+      GraphReducer graph_reducer(data.graph());
       // TODO(titzer): Figure out if we should run all reducers at once here.
       graph_reducer.AddReducer(&vn_reducer);
       graph_reducer.AddReducer(&simple_reducer);
       graph_reducer.AddReducer(&lowering);
       graph_reducer.AddReducer(&mach_reducer);
       graph_reducer.ReduceGraph();
 
       // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
       VerifyAndPrintGraph(data.graph(), "Lowered changes", true);
     }
 
     {
       PhaseScope phase_scope(pipeline_statistics.get(),
                              "late control reduction");
       SourcePositionTable::Scope pos(data.source_positions(),
                                      SourcePosition::Unknown());
       ZonePool::Scope zone_scope(data.zone_pool());
       ControlReducer::ReduceGraph(zone_scope.zone(), data.jsgraph(),
                                   data.common());
 
       VerifyAndPrintGraph(data.graph(), "Late Control reduced");
     }
   }
 
   {
     // Lower any remaining generic JSOperators.
     PhaseScope phase_scope(pipeline_statistics.get(), "generic lowering");
-    ZonePool::Scope zone_scope(data.zone_pool());
     SourcePositionTable::Scope pos(data.source_positions(),
                                    SourcePosition::Unknown());
     JSGenericLowering generic(info(), data.jsgraph());
     SelectLowering select(data.jsgraph()->graph(), data.jsgraph()->common());
-    GraphReducer graph_reducer(data.graph(), zone_scope.zone());
+    GraphReducer graph_reducer(data.graph());
     graph_reducer.AddReducer(&generic);
     graph_reducer.AddReducer(&select);
     graph_reducer.ReduceGraph();
 
     // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
     VerifyAndPrintGraph(data.graph(), "Lowered generic", true);
   }
 
   if (!pipeline_statistics.is_empty()) {
     pipeline_statistics->BeginPhaseKind("block building");
@@ skipping 182 matching lines @@
 }
 
 
 void Pipeline::TearDown() {
   InstructionOperand::TearDownCaches();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8