Eliminate excessive increment of deoptimization counters (e.g., with deep recursion of deoptimized …

runtime/vm/deferred_objects.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/deferred_objects.h"
 
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
 #include "vm/deopt_instructions.h"
 #include "vm/flags.h"
@@ skipping 155 matching lines @@
       Compiler::EnsureUnoptimizedCode(thread, function));
   if (!error.IsNull()) {
     Exceptions::PropagateError(error);
   }
   const Code& code = Code::Handle(zone, function.unoptimized_code());
   ASSERT(!code.IsNull());
   ASSERT(function.HasCode());
   *reinterpret_cast<RawObject**>(dest_addr) = code.raw();
 
   if (FLAG_trace_deoptimization_verbose) {
-    OS::PrintErr("materializing pc marker at 0x%" Px ": %s, %s\n",
-                 reinterpret_cast<uword>(slot()), code.ToCString(),
-                 function.ToCString());
+    THR_Print("materializing pc marker at 0x%" Px ": %s, %s\n",
+        reinterpret_cast<uword>(slot()), code.ToCString(),
+        function.ToCString());
   }
 
   // Increment the deoptimization counter. This effectively increments each
   // function occurring in the optimized frame.
-  function.set_deoptimization_counter(function.deoptimization_counter() + 1);
+  if (deopt_context->deoptimizing_code()) {
+    function.set_deoptimization_counter(function.deoptimization_counter() + 1);
+  }
   if (FLAG_trace_deoptimization || FLAG_trace_deoptimization_verbose) {
-    OS::PrintErr("Deoptimizing %s (count %d)\n",
+    THR_Print("Deoptimizing '%s' (count %d)\n",
         function.ToFullyQualifiedCString(),
         function.deoptimization_counter());
   }
   // Clear invocation counter so that hopefully the function gets reoptimized
   // only after more feedback has been collected.
   function.set_usage_counter(0);
   if (function.HasOptimizedCode()) {
     function.SwitchToUnoptimizedCode();
   }
 }
@@ skipping 133 matching lines @@
           OS::PrintErr("    null Field @ offset(%" Pd ") <- %s\n",
                        offset.Value(),
                        value.ToCString());
         }
       }
     }
   }
 }
 
 }  // namespace dart