DBC: Only try Smi fastpath in unoptimized code

runtime/vm/intermediate_language.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/intermediate_language.h"
 
 #include "vm/bit_vector.h"
 #include "vm/bootstrap.h"
 #include "vm/compiler.h"
 #include "vm/constant_propagator.h"
@@ skipping 3168 matching lines @@
                                  deopt_id(), token_pos(), locs());
     } else {
       compiler->GenerateInstanceCall(deopt_id(),
                                      token_pos(),
                                      ArgumentCount(),
                                      locs(),
                                      *call_ic_data);
     }
   }
 #else
-  ICData* ic_data = &ICData::ZoneHandle(call_ic_data->Original());
+  ICData* original_ic_data = &ICData::ZoneHandle(call_ic_data->Original());
 
   // Emit smi fast path instruction. If fast-path succeeds it skips the next
-  // instruction otherwise it falls through.
-  TryFastPathSmiOp(compiler, ic_data, function_name());
+  // instruction otherwise it falls through. Only attempt in unoptimized code
+  // because TryFastPathSmiOp will update original_ic_data.
+  if (!compiler->is_optimizing()) {
+    TryFastPathSmiOp(compiler, original_ic_data, function_name());
+  }
 
-  const intptr_t call_ic_data_kidx = __ AddConstant(*call_ic_data);
-  switch (ic_data->NumArgsTested()) {
+  const intptr_t call_ic_data_kidx = __ AddConstant(*original_ic_data);
+  switch (original_ic_data->NumArgsTested()) {
     case 1:
       if (compiler->is_optimizing()) {
         __ InstanceCall1Opt(ArgumentCount(), call_ic_data_kidx);
       } else {
         __ InstanceCall1(ArgumentCount(), call_ic_data_kidx);
       }
       break;
     case 2:
       if (compiler->is_optimizing()) {
         __ InstanceCall2Opt(ArgumentCount(), call_ic_data_kidx);
@@ skipping 716 matching lines @@
   set_native_c_function(native_function);
   function().SetIsNativeAutoSetupScope(auto_setup_scope);
   Dart_NativeEntryResolver resolver = library.native_entry_resolver();
   bool is_bootstrap_native = Bootstrap::IsBootstapResolver(resolver);
   set_is_bootstrap_native(is_bootstrap_native);
 }
 
 #undef __
 
 }  // namespace dart