Serializer: ensure unique script ids when deserializing.

R=jochen@chromium.org

Review URL: https://codereview.chromium.org/1035523005

Cr-Commit-Position: refs/heads/master@{#27471}

src/factory.cc

@@ -825,17 +825,12 @@ Handle<ExecutableAccessorInfo> Factory::NewExecutableAccessorInfo() {
 
 
 Handle<Script> Factory::NewScript(Handle<String> source) {
-  // Generate id for this script.
-  Heap* heap = isolate()->heap();
-  int id = heap->last_script_id()->value() + 1;
-  if (!Smi::IsValid(id) || id < 0) id = 1;
-  heap->set_last_script_id(Smi::FromInt(id));
-
   // Create and initialize script object.
+  Heap* heap = isolate()->heap();
   Handle<Script> script = Handle<Script>::cast(NewStruct(SCRIPT_TYPE));
   script->set_source(*source);
   script->set_name(heap->undefined_value());
-  script->set_id(Smi::FromInt(id));
+  script->set_id(isolate()->heap()->NextScriptId());
   script->set_line_offset(Smi::FromInt(0));
   script->set_column_offset(Smi::FromInt(0));
   script->set_context_data(heap->undefined_value());

src/heap/heap.h

@@ -1349,6 +1349,14 @@ class Heap {
     return seed;
   }
 
+  Smi* NextScriptId() {
+    int next_id = last_script_id()->value() + 1;
+    if (!Smi::IsValid(next_id) || next_id < 0) next_id = 1;
+    Smi* next_id_smi = Smi::FromInt(next_id);
+    set_last_script_id(next_id_smi);
+    return next_id_smi;
+  }
+
   void SetArgumentsAdaptorDeoptPCOffset(int pc_offset) {
     DCHECK(arguments_adaptor_deopt_pc_offset() == Smi::FromInt(0));
     set_arguments_adaptor_deopt_pc_offset(Smi::FromInt(pc_offset));

src/runtime/runtime-debug.cc

@@ -2329,6 +2329,7 @@ RUNTIME_FUNCTION(Runtime_DebugGetLoadedScripts) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 0);
 
+  DebugScope debug_scope(isolate->debug());
   // Fill the script objects.
   Handle<FixedArray> instances = isolate->debug()->GetLoadedScripts();
 

src/serialize.cc

@@ -720,6 +720,8 @@ HeapObject* Deserializer::ProcessNewObjectFromSerializedCode(HeapObject* obj) {
       string->SetForwardedInternalizedString(canonical);
       return canonical;
     }
+  } else if (obj->IsScript()) {
+    Script::cast(obj)->set_id(isolate_->heap()->NextScriptId());
   }
   return obj;
 }

test/mjsunit/debug-breakpoints.js

@@ -29,6 +29,8 @@
 // Get the Debug object exposed from the debug context global object.
 Debug = debug.Debug
 
+Debug.setListener(function() {});
+
 function f() {a=1;b=2}
 function g() {
   a=1;

test/mjsunit/deserialize-script-id.js

+// Copyright 2015 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.
+
+// Flags: --allow-natives-syntax --cache=code
+// Test that script ids are unique and we found the correct ones.
+
+var scripts = %DebugGetLoadedScripts();
+scripts.sort(function(a, b) { return a.id - b.id; });
+var user_script_count = 0;
+scripts.reduce(function(prev, cur) {
+  assertTrue(prev === undefined || prev.id != cur.id);
+  if (cur.type == 2) user_script_count++;
+});
+
+// Found mjsunit.js and this script.
+assertEquals(2, user_script_count);