[turbofan] Single entry into deferred regions

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 1505 matching lines @@
   if (run_verifier) {
     verifier_zone.Reset(new Zone(isolate()->allocator()));
     verifier = new (verifier_zone.get()) RegisterAllocatorVerifier(
         verifier_zone.get(), config, data->sequence());
   }
 
   base::SmartArrayPointer<char> debug_name;
 #ifdef DEBUG
   debug_name = info()->GetDebugName();
   data_->sequence()->ValidateEdgeSplitForm();
+  data_->sequence()->ValidateDeferredBlockEntryPaths();
   data_->sequence()->ValidateDeferredBlockExitPaths();
 #endif
 
   data->InitializeRegisterAllocationData(config, descriptor, debug_name.get());
   if (info()->is_osr()) {
     OsrHelper osr_helper(info());
     osr_helper.SetupFrame(data->frame());
   }
 
   Run<MeetRegisterConstraintsPhase>();
@@ skipping 58 matching lines @@
   }
 
   data->DeleteRegisterAllocationZone();
 }
 
 Isolate* Pipeline::isolate() const { return info()->isolate(); }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8