Move symbol table from per isolate snapshot to vm isolate snapshot, this reduces the per isolate in…

runtime/vm/dart_api_message.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/dart_api_message.h"
 #include "vm/object.h"
 #include "vm/snapshot_ids.h"
 #include "vm/symbols.h"
 #include "vm/unicode.h"
 
 namespace dart {
 
 static const int kNumInitialReferences = 4;
 
 ApiMessageReader::ApiMessageReader(const uint8_t* buffer,
                                    intptr_t length,
-                                   ReAlloc alloc)
+                                   ReAlloc alloc,
+                                   bool use_vm_isolate_snapshot)
     : BaseReader(buffer, length),
       alloc_(alloc),
       backward_references_(kNumInitialReferences),
-      vm_symbol_references_(NULL) {
+      vm_symbol_references_(NULL),
+      max_vm_isolate_object_id_(
+          use_vm_isolate_snapshot ?
+          Object::vm_isolate_snapshot_object_table().Length() : 0) {
   Init();
 }
 
 
 void ApiMessageReader::Init() {
   // Initialize marker objects used to handle Lists.
   // TODO(sjesse): Remove this when message serialization format is
   // updated.
   memset(&type_arguments_marker, 0, sizeof(type_arguments_marker));
   memset(&dynamic_type_marker, 0, sizeof(dynamic_type_marker));
@@ skipping 156 matching lines @@
   value->value.as_array.length = length;
   if (length > 0) {
     value->value.as_array.values = reinterpret_cast<Dart_CObject**>(value + 1);
   } else {
     value->value.as_array.values = NULL;
   }
   return value;
 }
 
 
+Dart_CObject* ApiMessageReader::AllocateDartCObjectVmIsolateObj(intptr_t id) {
+  return CreateDartCObjectString(VmIsolateSnapshotObject(id));
+}
+
+
 Dart_CObject_Internal* ApiMessageReader::AllocateDartCObjectInternal(
     Dart_CObject_Internal::Type type) {
   Dart_CObject_Internal* value =
       reinterpret_cast<Dart_CObject_Internal*>(
           alloc_(NULL, 0, sizeof(Dart_CObject_Internal)));
   ASSERT(value != NULL);
   value->type = static_cast<Dart_CObject_Type>(type);
   return value;
 }
 
@@ skipping 154 matching lines @@
   }
 
   if (vm_symbol_references_ == NULL) {
     intptr_t size =
         (sizeof(*vm_symbol_references_) * Symbols::kMaxPredefinedId);
     vm_symbol_references_ =
         reinterpret_cast<Dart_CObject**>(alloc_(NULL, 0, size));
     memset(vm_symbol_references_, 0, size);
   }
 
-  RawOneByteString* str =
-      reinterpret_cast<RawOneByteString*>(Symbols::GetVMSymbol(object_id));
-  intptr_t len = Smi::Value(str->ptr()->length_);
-  object = AllocateDartCObjectString(len);
-  char* p = object->value.as_string;
-  memmove(p, str->ptr()->data(), len);
-  p[len] = '\0';
+  object = CreateDartCObjectString(Symbols::GetVMSymbol(object_id));
   ASSERT(vm_symbol_references_[symbol_id] == NULL);
   vm_symbol_references_[symbol_id] = object;
   return object;
 }
 
 
 intptr_t ApiMessageReader::NextAvailableObjectId() const {
-  return backward_references_.length() + kMaxPredefinedObjectIds;
+  return backward_references_.length() +
+      kMaxPredefinedObjectIds + max_vm_isolate_object_id_;
+}
+
+
+Dart_CObject* ApiMessageReader::CreateDartCObjectString(RawObject* raw) {
+  ASSERT(RawObject::IsOneByteStringClassId(raw->GetClassId()));
+  RawOneByteString* raw_str = reinterpret_cast<RawOneByteString*>(raw);
+  intptr_t len = Smi::Value(raw_str->ptr()->length_);
+  Dart_CObject* object = AllocateDartCObjectString(len);
+  char* p = object->value.as_string;
+  memmove(p, raw_str->ptr()->data(), len);
+  p[len] = '\0';
+  return object;
 }
 
 
 Dart_CObject* ApiMessageReader::ReadObjectRef() {
   int64_t value64 = Read<int64_t>();
   if ((value64 & kSmiTagMask) == 0) {
     int64_t untagged_value = value64 >> kSmiTagShift;
     if ((kMinInt32 <= untagged_value) && (untagged_value <= kMaxInt32)) {
       return AllocateDartCObjectInt32(static_cast<int32_t>(untagged_value));
     } else {
@@ skipping 331 matching lines @@
 Dart_CObject* ApiMessageReader::ReadIndexedObject(intptr_t object_id) {
   if (object_id == kDynamicType ||
       object_id == kDoubleType ||
       object_id == kIntType ||
       object_id == kBoolType ||
       object_id == kStringType) {
     // Always return dynamic type (this is only a marker).
     return &dynamic_type_marker;
   }
   intptr_t index = object_id - kMaxPredefinedObjectIds;
+  if (index < max_vm_isolate_object_id_) {
+    return AllocateDartCObjectVmIsolateObj(index);
+  }
+  index -= max_vm_isolate_object_id_;
   ASSERT((0 <= index) && (index < backward_references_.length()));
   ASSERT(backward_references_[index]->reference() != NULL);
   return backward_references_[index]->reference();
 }
 
 
 Dart_CObject* ApiMessageReader::ReadObject() {
   Dart_CObject* value = ReadObjectImpl();
   for (intptr_t i = 0; i < backward_references_.length(); i++) {
     if (!backward_references_[i]->is_deserialized()) {
@@ skipping 30 matching lines @@
     object_id = NextAvailableObjectId();
   }
   return ReadInlinedObject(object_id);
 }
 
 
 void ApiMessageReader::AddBackRef(intptr_t id,
                                   Dart_CObject* obj,
                                   DeserializeState state) {
   intptr_t index = (id - kMaxPredefinedObjectIds);
+  ASSERT(index >= max_vm_isolate_object_id_);
+  index -= max_vm_isolate_object_id_;
   ASSERT(index == backward_references_.length());
   BackRefNode* node = AllocateBackRefNode(obj, state);
   ASSERT(node != NULL);
   backward_references_.Add(node);
 }
 
 
 Dart_CObject* ApiMessageReader::GetBackRef(intptr_t id) {
   ASSERT(id >= kMaxPredefinedObjectIds);
   intptr_t index = (id - kMaxPredefinedObjectIds);
+  ASSERT(index >= max_vm_isolate_object_id_);
+  index -= max_vm_isolate_object_id_;
   if (index < backward_references_.length()) {
     return backward_references_[index]->reference();
   }
   return NULL;
 }
 
 
 void ApiMessageWriter::WriteMessage(intptr_t field_count, intptr_t *data) {
   // Write out the serialization header value for this object.
   WriteInlinedObjectHeader(kMaxPredefinedObjectIds);
@@ skipping 117 matching lines @@
   if (Smi::IsValid(value)) {
     WriteSmi(value);
   } else {
     WriteMint(object, value);
   }
 }
 
 
 void ApiMessageWriter::WriteInlinedHeader(Dart_CObject* object) {
   // Write out the serialization header value for this object.
-  WriteInlinedObjectHeader(kMaxPredefinedObjectIds + object_id_);
+  WriteInlinedObjectHeader(SnapshotWriter::FirstObjectId() + object_id_);
   // Mark object with its object id.
   MarkCObject(object, object_id_);
   // Advance object id.
   object_id_++;
 }
 
 
 bool ApiMessageWriter::WriteCObject(Dart_CObject* object) {
   if (IsCObjectMarked(object)) {
     intptr_t object_id = GetMarkedCObjectMark(object);
-    WriteIndexedObject(kMaxPredefinedObjectIds + object_id);
+    WriteIndexedObject(SnapshotWriter::FirstObjectId() + object_id);
     return true;
   }
 
   Dart_CObject_Type type = object->type;
   if (type == Dart_CObject_kArray) {
     const intptr_t array_length = object->value.as_array.length;
     if (array_length < 0 ||
         array_length > Array::kMaxElements) {
       return false;
     }
@@ skipping 14 matching lines @@
     }
     return true;
   }
   return WriteCObjectInlined(object, type);
 }
 
 
 bool ApiMessageWriter::WriteCObjectRef(Dart_CObject* object) {
   if (IsCObjectMarked(object)) {
     intptr_t object_id = GetMarkedCObjectMark(object);
-    WriteIndexedObject(kMaxPredefinedObjectIds + object_id);
+    WriteIndexedObject(SnapshotWriter::FirstObjectId() + object_id);
     return true;
   }
 
   Dart_CObject_Type type = object->type;
   if (type == Dart_CObject_kArray) {
     const intptr_t array_length = object->value.as_array.length;
     if (array_length < 0 ||
         array_length > Array::kMaxElements) {
       return false;
     }
@@ skipping 17 matching lines @@
       static_cast<Dart_CObject_Type>(object->type & kDartCObjectTypeMask);
   ASSERT(type == Dart_CObject_kArray);
   const intptr_t array_length = object->value.as_array.length;
   if (array_length < 0 ||
       array_length > Array::kMaxElements) {
     return false;
   }
 
   // Write out the serialization header value for this object.
   intptr_t object_id = GetMarkedCObjectMark(object);
-  WriteInlinedObjectHeader(kMaxPredefinedObjectIds + object_id);
+  WriteInlinedObjectHeader(SnapshotWriter::FirstObjectId() + object_id);
   // Write out the class and tags information.
   WriteIndexedObject(kArrayCid);
   WriteTags(0);
   // Write out the length information.
   WriteSmi(array_length);
   // Write out the type arguments.
   WriteNullObject();
   // Write out array elements.
   for (int i = 0; i < array_length; i++) {
     bool success = WriteCObjectRef(object->value.as_array.values[i]);
@@ skipping 193 matching lines @@
     if (!success) {
       UnmarkAllCObjects(object);
       return false;
     }
   }
   UnmarkAllCObjects(object);
   return true;
 }
 
 }  // namespace dart