[turbofan] Introduce explicit loop exits markers.

src/compiler/pipeline.cc

Index: src/compiler/pipeline.cc
diff --git a/src/compiler/pipeline.cc b/src/compiler/pipeline.cc
index 1c1bcd848f6ae712d7848ffbd666c31ee973994e..3e3b87951d141ae3e3e736574f316bab83aae5d2 100644
--- a/src/compiler/pipeline.cc
+++ b/src/compiler/pipeline.cc
@@ -945,6 +945,14 @@ struct RepresentationSelectionPhase {
   }
 };
 
+struct LoopExitEliminationPhase {
+  static const char* phase_name() { return "loop exit elimination"; }
+
+  void Run(PipelineData* data, Zone* temp_zone) {
+    LoopPeeler::EliminateLoopExits(data->graph(), temp_zone);
+  }
+};
+
 struct EarlyOptimizationPhase {
   static const char* phase_name() { return "early optimization"; }
 
@@ -1433,6 +1441,10 @@ bool PipelineImpl::CreateGraph() {
     Run<TypedLoweringPhase>();
     RunPrintAndVerify("Lowered typed");
 
+    // Eventually, loop peeling will be done here.
+    Run<LoopExitEliminationPhase>();
+    RunPrintAndVerify("Loop exits eliminated", true);
+
     if (FLAG_turbo_stress_loop_peeling) {
       Run<StressLoopPeelingPhase>();
       RunPrintAndVerify("Loop peeled");