Use a reserved stack local variable to store the Code object so that it can be looked up easily whe…

vm/code_generator.cc

 // Copyright (c) 2012, 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/code_generator.h"
 
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_entry.h"
@@ skipping 1424 matching lines @@
         deopt_node_id,
         function.ToFullyQualifiedCString(),
         continue_at_pc);
     const Class& cls = Class::Handle(function.owner());
     const Script& script = Script::Handle(cls.script());
     intptr_t line, column;
     script.GetTokenLocation(deopt_token_index, &line, &column);
     OS::Print("  Line: %d Column: %d ", line, column);
     OS::Print(">>  %s\n", String::Handle(script.GetLine(line)).ToCString());
   }
+  // Patch the return PC and saved PC marker in frame to point to the
+  // unoptimized version.
   caller_frame->set_pc(continue_at_pc);
+  caller_frame->SetEntrypointMarker(
+      unoptimized_code.EntryPoint() +
+      AssemblerMacros::kOffsetOfSavedPCfromEntrypoint);
+
   // Clear invocation counter so that the function gets optimized after
   // types/classes have been collected.
   function.set_usage_counter(0);
   function.set_deoptimization_counter(function.deoptimization_counter() + 1);
 
   // We have to skip the following otherwise the compiler will complain
   // when it attempts to install unoptimized code into a function that
   // was already deoptimized.
   if (function.HasOptimizedCode()) {
     // Get unoptimized code. Compilation restores (reenables) the entry of
@@ skipping 91 matching lines @@
       }
     }
   }
   // The cache is null terminated, therefore the loop above should never
   // terminate by itself.
   UNREACHABLE();
   return Code::null();
 }
 
 }  // namespace dart