[interpreter] Add ability to preserve bytecode.

src/debug/liveedit.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/debug/liveedit.h"
 
 #include "src/ast/scopes.h"
 #include "src/code-stubs.h"
 #include "src/compilation-cache.h"
 #include "src/compiler.h"
@@ skipping 968 matching lines @@
 
   if (shared_info->is_compiled()) {
     // Take whatever code we can get from the new shared function info. We
     // expect activations of neither the old bytecode nor old FCG code, since
     // the lowest activation is going to be restarted.
     Handle<Code> old_code(shared_info->code());
     Handle<Code> new_code(new_shared_info->code());
     // Clear old bytecode. This will trigger self-healing if we do not install
     // new bytecode.
     shared_info->ClearBytecodeArray();
-    if (old_code->is_interpreter_trampoline_builtin()) {
+    if (!shared_info->HasBaselineCode()) {
       // Every function from this SFI is interpreted.
-      if (new_code->is_interpreter_trampoline_builtin()) {
+      if (!new_shared_info->HasBaselineCode()) {
         // We have newly compiled bytecode. Simply replace the old one.
         shared_info->set_bytecode_array(new_shared_info->bytecode_array());
       } else {
         // Rely on self-healing for places that used to run bytecode.
         shared_info->ReplaceCode(*new_code);
       }
     } else {
       // Functions from this SFI can be either interpreted or running FCG.
       DCHECK(old_code->kind() == Code::FUNCTION);
       if (new_shared_info->HasBytecodeArray()) {
@@ skipping 920 matching lines @@
     scope_info_length++;
 
     current_scope = current_scope->outer_scope();
   }
 
   return scope_info_list;
 }
 
 }  // namespace internal
 }  // namespace v8