Reset opt count on optimized code map lookup failure.

src/code-stubs-hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1173 matching lines @@
             HValue* keyed_plus = AddUncasted<HAdd>(
                 keyed_minus, graph()->GetConstant1());
             HValue* code_object = Add<HLoadKeyed>(optimized_map,
                 keyed_plus, static_cast<HValue*>(NULL), FAST_ELEMENTS);
             BuildInstallOptimizedCode(js_function, native_context, code_object);
 
             // Fall out of the loop
             loop_builder.Break();
           }
           done_check.Else();
+          {
+            // The optimization count should be tied to the context, e.g. as
+            // entry in optimized code map.  But for simplicity's sake we just
+            // reset the opt count if the optimized code map lookup fails,
+            // because no optimized code exists for the current context.
+            HValue* opt_count_and_bailout_reason = Add<HLoadNamedField>(
+                shared_info, HObjectAccess::ForOptCountAndBailoutReason());
+            int32_t opt_count_mask =

[Jakob Kummerow, 2013/11/05 14:35:05]

BitField has a kMask which you can use. Note that you'll want the
DisabledOptimizationReasonBits::kMask, though, so that opt_count is zeroed out.

+                (1 << SharedFunctionInfo::OptCountBits::kSize - 1)
+                    << SharedFunctionInfo::OptCountBits::kShift;
+            HValue* mask = Add<HConstant>(opt_count_mask);
+            HValue* result = Add<HBitwise>(
+                Token::BIT_AND, opt_count_and_bailout_reason, mask);
+            Add<HStoreNamedField>(shared_info,
+                                  HObjectAccess::ForOptCountAndBailoutReason(),
+                                  result);
+          }
           done_check.End();
         }
         restore_check.End();
       }
       loop_builder.EndBody();
     }
     already_in.End();
   }
   is_optimized.End();
 }
@@ skipping 30 matching lines @@
   Add<HStoreNamedField>(js_function, HObjectAccess::ForElementsPointer(),
                         empty_fixed_array);
   Add<HStoreNamedField>(js_function, HObjectAccess::ForLiteralsPointer(),
                         empty_fixed_array);
   Add<HStoreNamedField>(js_function, HObjectAccess::ForPrototypeOrInitialMap(),
                         graph()->GetConstantHole());
   Add<HStoreNamedField>(js_function,
                         HObjectAccess::ForSharedFunctionInfoPointer(),
                         shared_info);
   Add<HStoreNamedField>(js_function, HObjectAccess::ForFunctionContextPointer(),
-                        shared_info);
-  Add<HStoreNamedField>(js_function, HObjectAccess::ForFunctionContextPointer(),
                         context());
 
   // Initialize the code pointer in the function to be the one
   // found in the shared function info object.
   // But first check if there is an optimized version for our context.
   if (FLAG_cache_optimized_code) {
     BuildInstallFromOptimizedCodeMap(js_function, shared_info, native_context);
   } else {
     BuildInstallCode(js_function, shared_info);
   }
 
   return js_function;
 }
 
 
 Handle<Code> FastNewClosureStub::GenerateCode(Isolate* isolate) {
   return DoGenerateCode(isolate, this);
 }
 
 
 } }  // namespace v8::internal