Reset opt count on optimized code map lookup failure.

src/code-stubs-hydrogen.cc

Index: src/code-stubs-hydrogen.cc
diff --git a/src/code-stubs-hydrogen.cc b/src/code-stubs-hydrogen.cc
index dfa5ecd8cf840a75086eb5b0d5bac86b839aceb3..5ad4c9d300ca82b56b3dafc8c23ccab82574fe0e 100644
--- a/src/code-stubs-hydrogen.cc
+++ b/src/code-stubs-hydrogen.cc
@@ -1191,6 +1191,24 @@ void CodeStubGraphBuilderBase::BuildInstallFromOptimizedCodeMap(
             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.
+            HObjectAccess field = HObjectAccess::ForOptCountAndBailoutReason().
+                WithRepresentation(Representation::Integer32());
+            HValue* opt_count_and_bailout_reason =
+                Add<HLoadNamedField>(shared_info, field);
+            static const int pseudo_smi_shift = 1;
+            int32_t opt_count_mask =
+                static_cast<int32_t>(~SharedFunctionInfo::OptCountBits::kMask)
+                    << pseudo_smi_shift;
+            HValue* mask = Add<HConstant>(opt_count_mask);
+            HValue* result = Add<HBitwise>(
+                Token::BIT_AND, opt_count_and_bailout_reason, mask);
+            Add<HStoreNamedField>(shared_info, field, result);
+          }
           done_check.End();
         }
         restore_check.End();
@@ -1241,8 +1259,6 @@ HValue* CodeStubGraphBuilder<FastNewClosureStub>::BuildCodeStub() {
                         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