Add compiler option for counting hotness in compiled code.

For eventually easier profiling of boot classpath and
system server.

bug: 30934496
Test: 674-hotness-compiled

Change-Id: I0f63c644527b74f6ef2649f481c2a1c731bb9f21
diff --git a/compiler/driver/compiler_options.h b/compiler/driver/compiler_options.h
index 3f66029..18b0913 100644
--- a/compiler/driver/compiler_options.h
+++ b/compiler/driver/compiler_options.h
@@ -274,6 +274,10 @@
     return dump_stats_;
   }
 
+  bool CountHotnessInCompiledCode() const {
+    return count_hotness_in_compiled_code_;
+  }
+
  private:
   bool ParseDumpInitFailures(const std::string& option, std::string* error_msg);
   void ParseDumpCfgPasses(const StringPiece& option, UsageFn Usage);
@@ -336,6 +340,10 @@
   // Whether code should be deduplicated.
   bool deduplicate_code_;
 
+  // Whether compiled code should increment the hotness count of ArtMethod. Note that the increments
+  // won't be atomic for performance reasons, so we accept races, just like in interpreter.
+  bool count_hotness_in_compiled_code_;
+
   RegisterAllocator::Strategy register_allocation_strategy_;
 
   // If not null, specifies optimization passes which will be run instead of defaults.