Eliminate LocalVarDescriptors in some corner cases

runtime/vm/compiler.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/compiler.h"
 
 #include "vm/assembler.h"
 
 #include "vm/ast_printer.h"
 #include "vm/block_scheduler.h"
@@ skipping 1259 matching lines @@
         }
         func.ClearICDataArray();
         func.ClearCode();
       }
     }
   }
   return error.raw();
 }
 
 
-static void CreateLocalVarDescriptors(const ParsedFunction& parsed_function) {
-  const Function& func = parsed_function.function();
-  LocalVarDescriptors& var_descs = LocalVarDescriptors::Handle();
-  var_descs = parsed_function.node_sequence()->scope()->GetVarDescriptors(func);
-  Code::Handle(func.unoptimized_code()).set_var_descriptors(var_descs);
-}
-
-
 void Compiler::CompileStaticInitializer(const Field& field) {
   ASSERT(field.is_static());
   if (field.initializer() != Function::null()) {
     // TODO(rmacnak): Investigate why this happens for _enum_names.
     OS::Print("Warning: Ignoring repeated request for initializer for %s\n",
               field.ToCString());
     return;
   }
   ASSERT(field.initializer() == Function::null());
   Thread* thread = Thread::Current();
@@ skipping 33 matching lines @@
       ParsedFunction* parsed_function =
           Parser::ParseStaticFieldInitializer(field);
 
       parsed_function->AllocateVariables();
       // Non-optimized code generator.
       DartCompilationPipeline pipeline;
       CompileParsedFunctionHelper(&pipeline,
                                   parsed_function,
                                   false,  // optimized
                                   Isolate::kNoDeoptId);
-      // Eagerly create local var descriptors.
-      CreateLocalVarDescriptors(*parsed_function);
-
       initializer = parsed_function->function().raw();
     }
     // Invoke the function to evaluate the expression.
-    const Object& result = PassiveObject::Handle(
-        DartEntry::InvokeFunction(initializer, Object::empty_array()));
-    return result.raw();
+    return DartEntry::InvokeFunction(initializer, Object::empty_array());
   } else {
     Thread* const thread = Thread::Current();
     Isolate* const isolate = thread->isolate();
     StackZone zone(thread);
     const Error& error =
         Error::Handle(thread->zone(), isolate->object_store()->sticky_error());
     isolate->object_store()->clear_sticky_error();
     return error.raw();
   }
   UNREACHABLE();
@@ skipping 43 matching lines @@
         parsed_function->current_context_var());
     parsed_function->AllocateVariables();
 
     // Non-optimized code generator.
     DartCompilationPipeline pipeline;
     CompileParsedFunctionHelper(&pipeline,
                                 parsed_function,
                                 false,
                                 Isolate::kNoDeoptId);
 
-    // Eagerly create local var descriptors.
-    CreateLocalVarDescriptors(*parsed_function);
     const Object& result = PassiveObject::Handle(
         DartEntry::InvokeFunction(func, Object::empty_array()));
     return result.raw();
   } else {
     Thread* const thread = Thread::Current();
     Isolate* const isolate = thread->isolate();
     const Object& result =
       PassiveObject::Handle(isolate->object_store()->sticky_error());
     isolate->object_store()->clear_sticky_error();
     return result.raw();
   }
   UNREACHABLE();
   return Object::null();
 }
 
 }  // namespace dart