[turbofan] Remove the unused loop peeling stress option.

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 1157 matching lines @@
     GraphTrimmer trimmer(temp_zone, data->graph());
     NodeVector roots(temp_zone);
     if (data->jsgraph()) {
       data->jsgraph()->GetCachedNodes(&roots);
     }
     trimmer.TrimGraph(roots.begin(), roots.end());
   }
 };
 
 
-struct StressLoopPeelingPhase {
-  static const char* phase_name() { return "stress loop peeling"; }
-
-  void Run(PipelineData* data, Zone* temp_zone) {
-    // Peel the first outer loop for testing.
-    // 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 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 325 matching lines @@
     RunPrintAndVerify("Lowered typed");
 
     if (data->info()->is_loop_peeling_enabled()) {
       Run<LoopPeelingPhase>();
       RunPrintAndVerify("Loops peeled", true);
     } else {
       Run<LoopExitEliminationPhase>();
       RunPrintAndVerify("Loop exits eliminated", true);
     }
 
-    if (FLAG_turbo_stress_loop_peeling) {
-      Run<StressLoopPeelingPhase>();
-      RunPrintAndVerify("Loop peeled");
-    }
-
     if (!info()->shared_info()->asm_function()) {
       if (FLAG_turbo_load_elimination) {
         Run<LoadEliminationPhase>();
         RunPrintAndVerify("Load eliminated");
       }
 
       if (FLAG_turbo_escape) {
         Run<EscapeAnalysisPhase>();
         if (data->compilation_failed()) {
           info()->AbortOptimization(kCyclicObjectStateDetectedInEscapeAnalysis);
@@ skipping 446 matching lines @@
   data->DeleteRegisterAllocationZone();
 }
 
 CompilationInfo* PipelineImpl::info() const { return data_->info(); }
 
 Isolate* PipelineImpl::isolate() const { return info()->isolate(); }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8