[turbofan] Initial version of allocation folding and write barrier elimination.

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"
 #include "src/base/platform/elapsed-timer.h"
 #include "src/compiler/ast-graph-builder.h"
 #include "src/compiler/ast-loop-assignment-analyzer.h"
 #include "src/compiler/basic-block-instrumentor.h"
 #include "src/compiler/branch-elimination.h"
 #include "src/compiler/bytecode-graph-builder.h"
-#include "src/compiler/change-lowering.h"
 #include "src/compiler/code-generator.h"
 #include "src/compiler/common-operator-reducer.h"
 #include "src/compiler/control-flow-optimizer.h"
 #include "src/compiler/dead-code-elimination.h"
 #include "src/compiler/effect-control-linearizer.h"
 #include "src/compiler/escape-analysis-reducer.h"
 #include "src/compiler/escape-analysis.h"
 #include "src/compiler/frame-elider.h"
 #include "src/compiler/graph-replay.h"
 #include "src/compiler/graph-trimmer.h"
@@ skipping 11 matching lines @@
 #include "src/compiler/js-inlining-heuristic.h"
 #include "src/compiler/js-intrinsic-lowering.h"
 #include "src/compiler/js-native-context-specialization.h"
 #include "src/compiler/js-typed-lowering.h"
 #include "src/compiler/jump-threading.h"
 #include "src/compiler/live-range-separator.h"
 #include "src/compiler/load-elimination.h"
 #include "src/compiler/loop-analysis.h"
 #include "src/compiler/loop-peeling.h"
 #include "src/compiler/machine-operator-reducer.h"
+#include "src/compiler/memory-optimizer.h"
 #include "src/compiler/move-optimizer.h"
 #include "src/compiler/osr.h"
 #include "src/compiler/pipeline-statistics.h"
 #include "src/compiler/register-allocator-verifier.h"
 #include "src/compiler/register-allocator.h"
 #include "src/compiler/schedule.h"
 #include "src/compiler/scheduler.h"
 #include "src/compiler/select-lowering.h"
 #include "src/compiler/simplified-lowering.h"
 #include "src/compiler/simplified-operator-reducer.h"
@@ skipping 953 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 linearizer(data->jsgraph(), schedule, temp_zone);
     linearizer.Run();
   }
 };
 
+struct MemoryOptimizationPhase {
+  static const char* phase_name() { return "memory optimization"; }
+
+  void Run(PipelineData* data, Zone* temp_zone) {
+    MemoryOptimizer optimizer(data->jsgraph(), temp_zone);
+    optimizer.Optimize();
+  }
+};
+
 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());
     ValueNumberingReducer value_numbering(temp_zone);
-    ChangeLowering lowering(&graph_reducer, 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, &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"; }
@@ skipping 401 matching lines @@
 
   Run<BranchEliminationPhase>();
   RunPrintAndVerify("Branch conditions eliminated", true);
 
   // Optimize control flow.
   if (FLAG_turbo_cf_optimization) {
     Run<ControlFlowOptimizationPhase>();
     RunPrintAndVerify("Control flow optimized", true);
   }
 
+  // Optimize memory access and allocation operations.
+  Run<MemoryOptimizationPhase>();
+  // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
+  RunPrintAndVerify("Memory optimized", true);
+
   // Lower changes that have been inserted before.
   Run<LateOptimizationPhase>();
   // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
   RunPrintAndVerify("Late optimized", true);
 
   Run<LateGraphTrimmingPhase>();
   // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
   RunPrintAndVerify("Late trimmed", true);
 
   data->source_positions()->RemoveDecorator();
@@ skipping 328 matching lines @@
   data->DeleteRegisterAllocationZone();
 }
 
 CompilationInfo* PipelineImpl::info() const { return data_->info(); }
 
 Isolate* PipelineImpl::isolate() const { return info()->isolate(); }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8