Fix MSAN error on arm64 bot.

src/log.cc

 // Copyright 2011 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/log.h"
 
 #include <cstdarg>
 #include <sstream>
 
 #include "src/bailout-reason.h"
@@ skipping 629 matching lines @@
     profiler_ = NULL;
     if (IsActive()) Stop();
     DecreaseProfilingDepth();
     sampling_thread_->Join();
   }
 
   void SampleStack(const v8::RegisterState& state) override {
     v8::Isolate* v8_isolate = isolate();
     Isolate* isolate = reinterpret_cast<Isolate*>(v8_isolate);
 #if defined(USE_SIMULATOR)
-    SimulatorHelper::FillRegisters(isolate,
-                                   const_cast<v8::RegisterState*>(&state));
+    if (!SimulatorHelper::FillRegisters(isolate,
+                                        const_cast<v8::RegisterState*>(&state)))
+      return;
 #endif
     TickSample* sample = isolate->cpu_profiler()->StartTickSample();
     TickSample sample_obj;
     if (sample == NULL) sample = &sample_obj;
     sample->Init(isolate, state, TickSample::kIncludeCEntryFrame, true);
     if (is_counting_samples_ && !sample->timestamp.IsNull()) {
       if (sample->state == JS) ++js_sample_count_;
       if (sample->state == EXTERNAL) ++external_sample_count_;
     }
     if (profiler_) profiler_->Insert(sample);
@@ skipping 1216 matching lines @@
 
   if (profiler_listener_.get() != nullptr) {
     removeCodeEventListener(profiler_listener_.get());
   }
 
   return log_->Close();
 }
 
 }  // namespace internal
 }  // namespace v8