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dart / sdk.git / refs/heads/2-10-pkgs / . / runtime / vm / snapshot.cc
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// 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/snapshot.h"
#include "platform/assert.h"
#include "vm/bootstrap.h"
#include "vm/class_finalizer.h"
#include "vm/dart.h"
#include "vm/exceptions.h"
#include "vm/heap/heap.h"
#include "vm/longjump.h"
#include "vm/message.h"
#include "vm/object.h"
#include "vm/object_store.h"
#include "vm/snapshot_ids.h"
#include "vm/stub_code.h"
#include "vm/symbols.h"
#include "vm/timeline.h"
#include "vm/type_testing_stubs.h"
#include "vm/version.h"
// We currently only expect the Dart mutator to read snapshots.
#define ASSERT_NO_SAFEPOINT_SCOPE() \
isolate()->AssertCurrentThreadIsMutator(); \
ASSERT(thread()->no_safepoint_scope_depth() != 0)
namespace dart {
static const int kNumInitialReferences = 32;
static bool IsSingletonClassId(intptr_t class_id) {
// Check if this is a singleton object class which is shared by all isolates.
return ((class_id >= kClassCid && class_id <= kUnwindErrorCid) ||
(class_id == kTypeArgumentsCid) ||
(class_id >= kNullCid && class_id <= kVoidCid));
}
static bool IsBootstrapedClassId(intptr_t class_id) {
// Check if this is a class which is created during bootstrapping.
return (class_id == kObjectCid ||
(class_id >= kInstanceCid && class_id <= kUserTagCid) ||
class_id == kArrayCid || class_id == kImmutableArrayCid ||
IsStringClassId(class_id) || IsTypedDataClassId(class_id) ||
IsExternalTypedDataClassId(class_id) ||
IsTypedDataViewClassId(class_id) || class_id == kNullCid ||
class_id == kNeverCid || class_id == kTransferableTypedDataCid);
}
static bool IsObjectStoreTypeId(intptr_t index) {
// Check if this is a type which is stored in the object store.
static_assert(kFirstTypeArgumentsSnapshotId == kLastTypeSnapshotId + 1,
"Type and type arguments snapshot ids should be adjacent");
return index >= kFirstTypeSnapshotId && index <= kLastTypeArgumentsSnapshotId;
}
static bool IsSplitClassId(intptr_t class_id) {
// Return whether this class is serialized in two steps: first a reference,
// with sufficient information to allocate a correctly sized object, and then
// later inline with complete contents.
return class_id >= kNumPredefinedCids || class_id == kArrayCid ||
class_id == kImmutableArrayCid || class_id == kObjectPoolCid ||
IsImplicitFieldClassId(class_id);
}
static intptr_t ClassIdFromObjectId(intptr_t object_id) {
ASSERT(object_id > kClassIdsOffset);
intptr_t class_id = (object_id - kClassIdsOffset);
return class_id;
}
static intptr_t ObjectIdFromClassId(intptr_t class_id) {
ASSERT((class_id > kIllegalCid) && (class_id < kNumPredefinedCids));
return (class_id + kClassIdsOffset);
}
static ObjectPtr GetType(ObjectStore* object_store, intptr_t index) {
switch (index) {
case kLegacyObjectType:
return object_store->legacy_object_type();
case kNullableObjectType:
return object_store->nullable_object_type();
case kNullType:
return object_store->null_type();
case kNeverType:
return object_store->never_type();
case kLegacyFunctionType:
return object_store->legacy_function_type();
case kLegacyNumberType:
return object_store->legacy_number_type();
case kLegacySmiType:
return object_store->legacy_smi_type();
case kLegacyMintType:
return object_store->legacy_mint_type();
case kLegacyDoubleType:
return object_store->legacy_double_type();
case kLegacyIntType:
return object_store->legacy_int_type();
case kLegacyBoolType:
return object_store->legacy_bool_type();
case kLegacyStringType:
return object_store->legacy_string_type();
case kLegacyArrayType:
return object_store->legacy_array_type();
case kLegacyIntTypeArguments:
return object_store->type_argument_legacy_int();
case kLegacyDoubleTypeArguments:
return object_store->type_argument_legacy_double();
case kLegacyStringTypeArguments:
return object_store->type_argument_legacy_string();
case kLegacyStringDynamicTypeArguments:
return object_store->type_argument_legacy_string_dynamic();
case kLegacyStringLegacyStringTypeArguments:
return object_store->type_argument_legacy_string_legacy_string();
case kNonNullableObjectType:
return object_store->non_nullable_object_type();
case kNonNullableFunctionType:
return object_store->non_nullable_function_type();
case kNonNullableNumberType:
return object_store->non_nullable_number_type();
case kNonNullableSmiType:
return object_store->non_nullable_smi_type();
case kNonNullableMintType:
return object_store->non_nullable_mint_type();
case kNonNullableDoubleType:
return object_store->non_nullable_double_type();
case kNonNullableIntType:
return object_store->non_nullable_int_type();
case kNonNullableBoolType:
return object_store->non_nullable_bool_type();
case kNonNullableStringType:
return object_store->non_nullable_string_type();
case kNonNullableArrayType:
return object_store->non_nullable_array_type();
case kNonNullableIntTypeArguments:
return object_store->type_argument_non_nullable_int();
case kNonNullableDoubleTypeArguments:
return object_store->type_argument_non_nullable_double();
case kNonNullableStringTypeArguments:
return object_store->type_argument_non_nullable_string();
case kNonNullableStringDynamicTypeArguments:
return object_store->type_argument_non_nullable_string_dynamic();
case kNonNullableStringNonNullableStringTypeArguments:
return object_store
->type_argument_non_nullable_string_non_nullable_string();
default:
break;
}
UNREACHABLE();
return Type::null();
}
static intptr_t GetTypeIndex(ObjectStore* object_store,
const ObjectPtr raw_type) {
if (raw_type == object_store->legacy_object_type()) {
return kLegacyObjectType;
} else if (raw_type == object_store->null_type()) {
return kNullType;
} else if (raw_type == object_store->never_type()) {
return kNeverType;
} else if (raw_type == object_store->legacy_function_type()) {
return kLegacyFunctionType;
} else if (raw_type == object_store->legacy_number_type()) {
return kLegacyNumberType;
} else if (raw_type == object_store->legacy_smi_type()) {
return kLegacySmiType;
} else if (raw_type == object_store->legacy_mint_type()) {
return kLegacyMintType;
} else if (raw_type == object_store->legacy_double_type()) {
return kLegacyDoubleType;
} else if (raw_type == object_store->legacy_int_type()) {
return kLegacyIntType;
} else if (raw_type == object_store->legacy_bool_type()) {
return kLegacyBoolType;
} else if (raw_type == object_store->legacy_string_type()) {
return kLegacyStringType;
} else if (raw_type == object_store->legacy_array_type()) {
return kLegacyArrayType;
} else if (raw_type == object_store->type_argument_legacy_int()) {
return kLegacyIntTypeArguments;
} else if (raw_type == object_store->type_argument_legacy_double()) {
return kLegacyDoubleTypeArguments;
} else if (raw_type == object_store->type_argument_legacy_string()) {
return kLegacyStringTypeArguments;
} else if (raw_type == object_store->type_argument_legacy_string_dynamic()) {
return kLegacyStringDynamicTypeArguments;
} else if (raw_type ==
object_store->type_argument_legacy_string_legacy_string()) {
return kLegacyStringLegacyStringTypeArguments;
} else if (raw_type == object_store->non_nullable_object_type()) {
return kNonNullableObjectType;
} else if (raw_type == object_store->non_nullable_function_type()) {
return kNonNullableFunctionType;
} else if (raw_type == object_store->non_nullable_number_type()) {
return kNonNullableNumberType;
} else if (raw_type == object_store->non_nullable_smi_type()) {
return kNonNullableSmiType;
} else if (raw_type == object_store->non_nullable_mint_type()) {
return kNonNullableMintType;
} else if (raw_type == object_store->non_nullable_double_type()) {
return kNonNullableDoubleType;
} else if (raw_type == object_store->non_nullable_int_type()) {
return kNonNullableIntType;
} else if (raw_type == object_store->non_nullable_bool_type()) {
return kNonNullableBoolType;
} else if (raw_type == object_store->non_nullable_string_type()) {
return kNonNullableStringType;
} else if (raw_type == object_store->non_nullable_array_type()) {
return kNonNullableArrayType;
} else if (raw_type == object_store->type_argument_non_nullable_int()) {
return kNonNullableIntTypeArguments;
} else if (raw_type == object_store->type_argument_non_nullable_double()) {
return kNonNullableDoubleTypeArguments;
} else if (raw_type == object_store->type_argument_non_nullable_string()) {
return kNonNullableStringTypeArguments;
} else if (raw_type ==
object_store->type_argument_non_nullable_string_dynamic()) {
return kNonNullableStringDynamicTypeArguments;
} else if (raw_type ==
object_store
->type_argument_non_nullable_string_non_nullable_string()) {
return kNonNullableStringNonNullableStringTypeArguments;
}
return kInvalidIndex;
}
const char* Snapshot::KindToCString(Kind kind) {
switch (kind) {
case kFull:
return "full";
case kFullJIT:
return "full-jit";
case kFullAOT:
return "full-aot";
case kMessage:
return "message";
case kNone:
return "none";
case kInvalid:
default:
return "invalid";
}
}
const Snapshot* Snapshot::SetupFromBuffer(const void* raw_memory) {
ASSERT(raw_memory != NULL);
const Snapshot* snapshot = reinterpret_cast<const Snapshot*>(raw_memory);
if (!snapshot->check_magic()) {
return NULL;
}
// If the raw length is negative or greater than what the local machine can
// handle, then signal an error.
int64_t length = snapshot->large_length();
if ((length < 0) || (length > kIntptrMax)) {
return NULL;
}
return snapshot;
}
SmiPtr BaseReader::ReadAsSmi() {
SmiPtr value = static_cast<SmiPtr>(Read<intptr_t>());
ASSERT((static_cast<uword>(value) & kSmiTagMask) == kSmiTag);
return value;
}
intptr_t BaseReader::ReadSmiValue() {
return Smi::Value(ReadAsSmi());
}
SnapshotReader::SnapshotReader(const uint8_t* buffer,
intptr_t size,
Snapshot::Kind kind,
ZoneGrowableArray<BackRefNode>* backward_refs,
Thread* thread)
: BaseReader(buffer, size),
kind_(kind),
thread_(thread),
zone_(thread->zone()),
heap_(isolate()->heap()),
old_space_(thread_->isolate()->heap()->old_space()),
cls_(Class::Handle(zone_)),
code_(Code::Handle(zone_)),
instance_(Instance::Handle(zone_)),
instructions_(Instructions::Handle(zone_)),
obj_(Object::Handle(zone_)),
pobj_(PassiveObject::Handle(zone_)),
array_(Array::Handle(zone_)),
field_(Field::Handle(zone_)),
str_(String::Handle(zone_)),
library_(Library::Handle(zone_)),
type_(AbstractType::Handle(zone_)),
type_arguments_(TypeArguments::Handle(zone_)),
tokens_(GrowableObjectArray::Handle(zone_)),
data_(ExternalTypedData::Handle(zone_)),
typed_data_base_(TypedDataBase::Handle(zone_)),
typed_data_(TypedData::Handle(zone_)),
typed_data_view_(TypedDataView::Handle(zone_)),
function_(Function::Handle(zone_)),
error_(UnhandledException::Handle(zone_)),
set_class_(Class::ZoneHandle(
zone_,
thread_->isolate()->object_store()->linked_hash_set_class())),
max_vm_isolate_object_id_(
(Snapshot::IsFull(kind))
? Object::vm_isolate_snapshot_object_table().Length()
: 0),
backward_references_(backward_refs),
types_to_postprocess_(GrowableObjectArray::Handle(zone_)),
objects_to_rehash_(GrowableObjectArray::Handle(zone_)) {}
ObjectPtr SnapshotReader::ReadObject() {
// Setup for long jump in case there is an exception while reading.
LongJumpScope jump;
if (setjmp(*jump.Set()) == 0) {
PassiveObject& obj =
PassiveObject::Handle(zone(), ReadObjectImpl(kAsInlinedObject));
for (intptr_t i = 0; i < backward_references_->length(); i++) {
if (!(*backward_references_)[i].is_deserialized()) {
ReadObjectImpl(kAsInlinedObject);
(*backward_references_)[i].set_state(kIsDeserialized);
}
}
Object& result = Object::Handle(zone_);
if (backward_references_->length() > 0) {
result = (*backward_references_)[0].reference()->raw();
} else {
result = obj.raw();
}
RunDelayedTypePostprocessing();
const Object& ok = Object::Handle(zone_, RunDelayedRehashingOfMaps());
objects_to_rehash_ = GrowableObjectArray::null();
if (!ok.IsNull()) {
return ok.raw();
}
return result.raw();
} else {
// An error occurred while reading, return the error object.
return Thread::Current()->StealStickyError();
}
}
void SnapshotReader::EnqueueTypePostprocessing(const AbstractType& type) {
if (types_to_postprocess_.IsNull()) {
types_to_postprocess_ = GrowableObjectArray::New();
}
types_to_postprocess_.Add(type);
}
void SnapshotReader::RunDelayedTypePostprocessing() {
if (types_to_postprocess_.IsNull()) {
return;
}
AbstractType& type = AbstractType::Handle();
Code& code = Code::Handle();
for (intptr_t i = 0; i < types_to_postprocess_.Length(); ++i) {
type ^= types_to_postprocess_.At(i);
code = TypeTestingStubGenerator::DefaultCodeForType(type);
type.SetTypeTestingStub(code);
}
}
void SnapshotReader::EnqueueRehashingOfMap(const LinkedHashMap& map) {
if (objects_to_rehash_.IsNull()) {
objects_to_rehash_ = GrowableObjectArray::New();
}
objects_to_rehash_.Add(map);
}
ObjectPtr SnapshotReader::RunDelayedRehashingOfMaps() {
if (!objects_to_rehash_.IsNull()) {
const Library& collections_lib =
Library::Handle(zone_, Library::CollectionLibrary());
const Function& rehashing_function = Function::Handle(
zone_,
collections_lib.LookupFunctionAllowPrivate(Symbols::_rehashObjects()));
ASSERT(!rehashing_function.IsNull());
const Array& arguments = Array::Handle(zone_, Array::New(1));
arguments.SetAt(0, objects_to_rehash_);
return DartEntry::InvokeFunction(rehashing_function, arguments);
}
return Object::null();
}
ClassPtr SnapshotReader::ReadClassId(intptr_t object_id) {
ASSERT(!Snapshot::IsFull(kind_));
// Read the class header information and lookup the class.
intptr_t class_header = Read<int32_t>();
ASSERT((class_header & kSmiTagMask) != kSmiTag);
ASSERT(!IsVMIsolateObject(class_header) ||
!IsSingletonClassId(GetVMIsolateObjectId(class_header)));
ASSERT((SerializedHeaderTag::decode(class_header) != kObjectId) ||
!IsBootstrapedClassId(SerializedHeaderData::decode(class_header)));
Class& cls = Class::ZoneHandle(zone(), Class::null());
AddBackRef(object_id, &cls, kIsDeserialized);
// Read the library/class information and lookup the class.
str_ ^= ReadObjectImpl(class_header, kAsInlinedObject);
library_ = Library::LookupLibrary(thread(), str_);
if (library_.IsNull() || !library_.Loaded()) {
SetReadException(
"Invalid object found in message: library is not found or loaded.");
}
str_ ^= ReadObjectImpl(kAsInlinedObject);
if (str_.raw() == Symbols::TopLevel().raw()) {
cls = library_.toplevel_class();
} else {
str_ = String::New(String::ScrubName(str_));
cls = library_.LookupClassAllowPrivate(str_);
}
if (cls.IsNull()) {
SetReadException("Invalid object found in message: class not found");
}
cls.EnsureIsFinalized(thread());
return cls.raw();
}
ObjectPtr SnapshotReader::ReadStaticImplicitClosure(intptr_t object_id,
intptr_t class_header) {
ASSERT(!Snapshot::IsFull(kind_));
// First create a function object and associate it with the specified
// 'object_id'.
Function& func = Function::Handle(zone(), Function::null());
Instance& obj = Instance::ZoneHandle(zone(), Instance::null());
AddBackRef(object_id, &obj, kIsDeserialized);
// Read the library/class/function information and lookup the function.
// Note: WriteStaticImplicitClosure is *not* scrubbing the names before
// writing them into the snapshot, because scrubbing requires allocation.
// This means that names we read here might be mangled with private
// keys. These keys need to be scrubbed before performing lookups
// otherwise lookups might fail.
str_ ^= ReadObjectImpl(kAsInlinedObject);
library_ = Library::LookupLibrary(thread(), str_);
if (library_.IsNull() || !library_.Loaded()) {
SetReadException("Invalid Library object found in message.");
}
str_ ^= ReadObjectImpl(kAsInlinedObject);
if (str_.Equals(Symbols::TopLevel())) {
str_ ^= ReadObjectImpl(kAsInlinedObject);
str_ = String::New(String::ScrubName(str_));
func = library_.LookupFunctionAllowPrivate(str_);
} else {
str_ = String::New(String::ScrubName(str_));
cls_ = library_.LookupClassAllowPrivate(str_);
if (cls_.IsNull()) {
OS::PrintErr("Name of class not found %s\n", str_.ToCString());
SetReadException("Invalid Class object found in message.");
}
cls_.EnsureIsFinalized(thread());
str_ ^= ReadObjectImpl(kAsInlinedObject);
str_ = String::New(String::ScrubName(str_));
func = cls_.LookupFunctionAllowPrivate(str_);
}
if (func.IsNull()) {
SetReadException("Invalid function object found in message.");
}
func = func.ImplicitClosureFunction();
ASSERT(!func.IsNull());
// Return the associated implicit static closure.
obj = func.ImplicitStaticClosure();
return obj.raw();
}
intptr_t SnapshotReader::NextAvailableObjectId() const {
return backward_references_->length() + kMaxPredefinedObjectIds +
max_vm_isolate_object_id_;
}
void SnapshotReader::SetReadException(const char* msg) {
const String& error_str = String::Handle(zone(), String::New(msg));
const Array& args = Array::Handle(zone(), Array::New(1));
args.SetAt(0, error_str);
Object& result = Object::Handle(zone());
const Library& library = Library::Handle(zone(), Library::CoreLibrary());
result = DartLibraryCalls::InstanceCreate(library, Symbols::ArgumentError(),
Symbols::Dot(), args);
const StackTrace& stacktrace = StackTrace::Handle(zone());
const UnhandledException& error = UnhandledException::Handle(
zone(), UnhandledException::New(Instance::Cast(result), stacktrace));
thread()->long_jump_base()->Jump(1, error);
}
ObjectPtr SnapshotReader::VmIsolateSnapshotObject(intptr_t index) const {
return Object::vm_isolate_snapshot_object_table().At(index);
}
bool SnapshotReader::is_vm_isolate() const {
return isolate() == Dart::vm_isolate();
}
ObjectPtr SnapshotReader::ReadObjectImpl(bool as_reference) {
int64_t header_value = Read<int64_t>();
if ((header_value & kSmiTagMask) == kSmiTag) {
return NewInteger(header_value);
}
ASSERT((header_value <= kIntptrMax) && (header_value >= kIntptrMin));
return ReadObjectImpl(static_cast<intptr_t>(header_value), as_reference);
}
ObjectPtr SnapshotReader::ReadObjectImpl(intptr_t header_value,
bool as_reference) {
if (IsVMIsolateObject(header_value)) {
return ReadVMIsolateObject(header_value);
}
if (SerializedHeaderTag::decode(header_value) == kObjectId) {
return ReadIndexedObject(SerializedHeaderData::decode(header_value));
}
ASSERT(SerializedHeaderTag::decode(header_value) == kInlined);
intptr_t object_id = SerializedHeaderData::decode(header_value);
if (object_id == kOmittedObjectId) {
object_id = NextAvailableObjectId();
}
// Read the class header information.
intptr_t class_header = Read<int32_t>();
intptr_t tags = ReadTags();
bool read_as_reference = as_reference && !ObjectLayout::IsCanonical(tags);
intptr_t header_id = SerializedHeaderData::decode(class_header);
if (header_id == kInstanceObjectId) {
return ReadInstance(object_id, tags, read_as_reference);
} else if (header_id == kStaticImplicitClosureObjectId) {
// We skip the tags that have been written as the implicit static
// closure is going to be created in this isolate or the canonical
// version already created in the isolate will be used.
return ReadStaticImplicitClosure(object_id, class_header);
}
ASSERT((class_header & kSmiTagMask) != kSmiTag);
intptr_t class_id = LookupInternalClass(class_header);
switch (class_id) {
#define SNAPSHOT_READ(clazz) \
case clazz::kClassId: { \
pobj_ = clazz::ReadFrom(this, object_id, tags, kind_, read_as_reference); \
break; \
}
CLASS_LIST_NO_OBJECT(SNAPSHOT_READ)
#undef SNAPSHOT_READ
#define SNAPSHOT_READ(clazz) case kTypedData##clazz##Cid:
CLASS_LIST_TYPED_DATA(SNAPSHOT_READ) {
tags = ObjectLayout::ClassIdTag::update(class_id, tags);
pobj_ =
TypedData::ReadFrom(this, object_id, tags, kind_, read_as_reference);
break;
}
#undef SNAPSHOT_READ
#define SNAPSHOT_READ(clazz) case kExternalTypedData##clazz##Cid:
CLASS_LIST_TYPED_DATA(SNAPSHOT_READ) {
tags = ObjectLayout::ClassIdTag::update(class_id, tags);
pobj_ = ExternalTypedData::ReadFrom(this, object_id, tags, kind_, true);
break;
}
#undef SNAPSHOT_READ
#define SNAPSHOT_READ(clazz) case kTypedData##clazz##ViewCid:
case kByteDataViewCid:
CLASS_LIST_TYPED_DATA(SNAPSHOT_READ) {
tags = ObjectLayout::ClassIdTag::update(class_id, tags);
pobj_ = TypedDataView::ReadFrom(this, object_id, tags, kind_, true);
break;
}
#undef SNAPSHOT_READ
#define SNAPSHOT_READ(clazz) case kFfi##clazz##Cid:
CLASS_LIST_FFI(SNAPSHOT_READ) { UNREACHABLE(); }
#undef SNAPSHOT_READ
default:
UNREACHABLE();
break;
}
return pobj_.raw();
}
void SnapshotReader::EnqueueRehashingOfSet(const Object& set) {
if (objects_to_rehash_.IsNull()) {
objects_to_rehash_ = GrowableObjectArray::New();
}
objects_to_rehash_.Add(set);
}
ObjectPtr SnapshotReader::ReadInstance(intptr_t object_id,
intptr_t tags,
bool as_reference) {
// Object is regular dart instance.
intptr_t instance_size = 0;
Instance* result = NULL;
DeserializeState state;
if (!as_reference) {
result = reinterpret_cast<Instance*>(GetBackRef(object_id));
state = kIsDeserialized;
} else {
state = kIsNotDeserialized;
}
if (result == NULL) {
result = &(Instance::ZoneHandle(zone(), Instance::null()));
AddBackRef(object_id, result, state);
cls_ ^= ReadObjectImpl(kAsInlinedObject);
ASSERT(!cls_.IsNull());
// Closure instances are handled by Closure::ReadFrom().
ASSERT(!cls_.IsClosureClass());
instance_size = cls_.host_instance_size();
ASSERT(instance_size > 0);
// Allocate the instance and read in all the fields for the object.
*result ^= Object::Allocate(cls_.id(), instance_size, Heap::kNew);
} else {
cls_ ^= ReadObjectImpl(kAsInlinedObject);
ASSERT(!cls_.IsNull());
instance_size = cls_.host_instance_size();
}
if (cls_.id() == set_class_.id()) {
EnqueueRehashingOfSet(*result);
}
if (!as_reference) {
// Read all the individual fields for inlined objects.
intptr_t next_field_offset = cls_.host_next_field_offset();
intptr_t type_argument_field_offset =
cls_.host_type_arguments_field_offset();
ASSERT(next_field_offset > 0);
// Instance::NextFieldOffset() returns the offset of the first field in
// a Dart object.
bool read_as_reference = ObjectLayout::IsCanonical(tags) ? false : true;
intptr_t offset = Instance::NextFieldOffset();
intptr_t result_cid = result->GetClassId();
const auto unboxed_fields =
isolate()->group()->shared_class_table()->GetUnboxedFieldsMapAt(
result_cid);
while (offset < next_field_offset) {
if (unboxed_fields.Get(offset / kWordSize)) {
uword* p = reinterpret_cast<uword*>(result->raw_value() -
kHeapObjectTag + offset);
// Reads 32 bits of the unboxed value at a time
*p = ReadWordWith32BitReads();
} else {
pobj_ = ReadObjectImpl(read_as_reference);
result->SetFieldAtOffset(offset, pobj_);
if ((offset != type_argument_field_offset) &&
(kind_ == Snapshot::kMessage) && isolate()->use_field_guards() &&
(pobj_.raw() != Object::sentinel().raw())) {
// TODO(fschneider): Consider hoisting these lookups out of the loop.
// This would involve creating a handle, since cls_ can't be reused
// across the call to ReadObjectImpl.
cls_ = isolate()->class_table()->At(result_cid);
array_ = cls_.OffsetToFieldMap();
field_ ^= array_.At(offset >> kWordSizeLog2);
ASSERT(!field_.IsNull());
ASSERT(field_.HostOffset() == offset);
obj_ = pobj_.raw();
field_.RecordStore(obj_);
}
// TODO(fschneider): Verify the guarded cid and length for other kinds
// of snapshot (kFull, kScript) with asserts.
}
offset += kWordSize;
}
if (ObjectLayout::IsCanonical(tags)) {
const char* error_str = NULL;
*result = result->CheckAndCanonicalize(thread(), &error_str);
if (error_str != NULL) {
FATAL1("Failed to canonicalize %s\n", error_str);
}
ASSERT(!result->IsNull());
}
}
return result->raw();
}
void SnapshotReader::AddBackRef(intptr_t id,
Object* 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(obj, state);
backward_references_->Add(node);
}
Object* SnapshotReader::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;
}
ApiErrorPtr SnapshotReader::VerifyVersionAndFeatures(Isolate* isolate) {
// If the version string doesn't match, return an error.
// Note: New things are allocated only if we're going to return an error.
const char* expected_version = Version::SnapshotString();
ASSERT(expected_version != NULL);
const intptr_t version_len = strlen(expected_version);
if (PendingBytes() < version_len) {
const intptr_t kMessageBufferSize = 128;
char message_buffer[kMessageBufferSize];
Utils::SNPrint(message_buffer, kMessageBufferSize,
"No full snapshot version found, expected '%s'",
expected_version);
// This can also fail while bringing up the VM isolate, so make sure to
// allocate the error message in old space.
const String& msg = String::Handle(String::New(message_buffer, Heap::kOld));
return ApiError::New(msg, Heap::kOld);
}
const char* version = reinterpret_cast<const char*>(CurrentBufferAddress());
ASSERT(version != NULL);
if (strncmp(version, expected_version, version_len) != 0) {
const intptr_t kMessageBufferSize = 256;
char message_buffer[kMessageBufferSize];
char* actual_version = Utils::StrNDup(version, version_len);
Utils::SNPrint(message_buffer, kMessageBufferSize,
"Wrong %s snapshot version, expected '%s' found '%s'",
(Snapshot::IsFull(kind_)) ? "full" : "script",
expected_version, actual_version);
free(actual_version);
// This can also fail while bringing up the VM isolate, so make sure to
// allocate the error message in old space.
const String& msg = String::Handle(String::New(message_buffer, Heap::kOld));
return ApiError::New(msg, Heap::kOld);
}
Advance(version_len);
const char* expected_features = Dart::FeaturesString(isolate, false, kind_);
ASSERT(expected_features != NULL);
const intptr_t expected_len = strlen(expected_features);
const char* features = reinterpret_cast<const char*>(CurrentBufferAddress());
ASSERT(features != NULL);
intptr_t buffer_len = Utils::StrNLen(features, PendingBytes());
if ((buffer_len != expected_len) ||
(strncmp(features, expected_features, expected_len) != 0)) {
const intptr_t kMessageBufferSize = 256;
char message_buffer[kMessageBufferSize];
char* actual_features =
Utils::StrNDup(features, buffer_len < 128 ? buffer_len : 128);
Utils::SNPrint(message_buffer, kMessageBufferSize,
"Snapshot not compatible with the current VM configuration: "
"the snapshot requires '%s' but the VM has '%s'",
actual_features, expected_features);
free(const_cast<char*>(expected_features));
free(actual_features);
// This can also fail while bringing up the VM isolate, so make sure to
// allocate the error message in old space.
const String& msg = String::Handle(String::New(message_buffer, Heap::kOld));
return ApiError::New(msg, Heap::kOld);
}
free(const_cast<char*>(expected_features));
Advance(expected_len + 1);
return ApiError::null();
}
ObjectPtr SnapshotReader::NewInteger(int64_t value) {
ASSERT((value & kSmiTagMask) == kSmiTag);
value = value >> kSmiTagShift;
if (Smi::IsValid(value)) {
return Smi::New(static_cast<intptr_t>(value));
}
return Mint::NewCanonical(value);
}
intptr_t SnapshotReader::LookupInternalClass(intptr_t class_header) {
// If the header is an object Id, lookup singleton VM classes or classes
// stored in the object store.
if (IsVMIsolateObject(class_header)) {
intptr_t class_id = GetVMIsolateObjectId(class_header);
ASSERT(IsSingletonClassId(class_id));
return class_id;
}
ASSERT(SerializedHeaderTag::decode(class_header) == kObjectId);
intptr_t class_id = SerializedHeaderData::decode(class_header);
ASSERT(IsBootstrapedClassId(class_id) || IsSingletonClassId(class_id));
return class_id;
}
#define READ_VM_SINGLETON_OBJ(id, obj) \
if (object_id == id) { \
return obj; \
}
ObjectPtr SnapshotReader::ReadVMIsolateObject(intptr_t header_value) {
intptr_t object_id = GetVMIsolateObjectId(header_value);
// First check if it is one of the singleton objects.
READ_VM_SINGLETON_OBJ(kNullObject, Object::null());
READ_VM_SINGLETON_OBJ(kSentinelObject, Object::sentinel().raw());
READ_VM_SINGLETON_OBJ(kTransitionSentinelObject,
Object::transition_sentinel().raw());
READ_VM_SINGLETON_OBJ(kEmptyArrayObject, Object::empty_array().raw());
READ_VM_SINGLETON_OBJ(kZeroArrayObject, Object::zero_array().raw());
READ_VM_SINGLETON_OBJ(kDynamicType, Object::dynamic_type().raw());
READ_VM_SINGLETON_OBJ(kVoidType, Object::void_type().raw());
READ_VM_SINGLETON_OBJ(kEmptyTypeArguments,
Object::empty_type_arguments().raw());
READ_VM_SINGLETON_OBJ(kTrueValue, Bool::True().raw());
READ_VM_SINGLETON_OBJ(kFalseValue, Bool::False().raw());
READ_VM_SINGLETON_OBJ(kExtractorParameterTypes,
Object::extractor_parameter_types().raw());
READ_VM_SINGLETON_OBJ(kExtractorParameterNames,
Object::extractor_parameter_names().raw());
READ_VM_SINGLETON_OBJ(kEmptyContextScopeObject,
Object::empty_context_scope().raw());
READ_VM_SINGLETON_OBJ(kEmptyObjectPool, Object::empty_object_pool().raw());
READ_VM_SINGLETON_OBJ(kEmptyDescriptors, Object::empty_descriptors().raw());
READ_VM_SINGLETON_OBJ(kEmptyVarDescriptors,
Object::empty_var_descriptors().raw());
READ_VM_SINGLETON_OBJ(kEmptyExceptionHandlers,
Object::empty_exception_handlers().raw());
// Check if it is a double.
if (object_id == kDoubleObject) {
ASSERT(kind_ == Snapshot::kMessage);
return Double::New(ReadDouble());
}
// Check it is a singleton class object.
intptr_t class_id = ClassIdFromObjectId(object_id);
if (IsSingletonClassId(class_id)) {
return isolate()->class_table()->At(class_id); // get singleton class.
}
// Check if it is a singleton Argument descriptor object.
for (intptr_t i = 0; i < ArgumentsDescriptor::kCachedDescriptorCount; i++) {
if (object_id == (kCachedArgumentsDescriptor0 + i)) {
return ArgumentsDescriptor::cached_args_descriptors_[i];
}
}
// Check if it is a singleton ICData array object.
for (intptr_t i = 0; i < ICData::kCachedICDataArrayCount; i++) {
if (object_id == (kCachedICDataArray0 + i)) {
return ICData::cached_icdata_arrays_[i];
}
}
ASSERT(Symbols::IsPredefinedSymbolId(object_id));
return Symbols::GetPredefinedSymbol(object_id); // return VM symbol.
}
ObjectPtr SnapshotReader::ReadIndexedObject(intptr_t object_id) {
intptr_t class_id = ClassIdFromObjectId(object_id);
if (IsBootstrapedClassId(class_id)) {
return isolate()->class_table()->At(class_id); // get singleton class.
}
if (IsObjectStoreTypeId(object_id)) {
return GetType(object_store(), object_id); // return type obj.
}
ASSERT(object_id >= kMaxPredefinedObjectIds);
intptr_t index = (object_id - kMaxPredefinedObjectIds);
if (index < max_vm_isolate_object_id_) {
return VmIsolateSnapshotObject(index);
}
return GetBackRef(object_id)->raw();
}
void SnapshotReader::ArrayReadFrom(intptr_t object_id,
const Array& result,
intptr_t len,
intptr_t tags) {
// Setup the object fields.
*TypeArgumentsHandle() ^= ReadObjectImpl(kAsInlinedObject);
result.SetTypeArguments(*TypeArgumentsHandle());
bool as_reference = ObjectLayout::IsCanonical(tags) ? false : true;
for (intptr_t i = 0; i < len; i++) {
*PassiveObjectHandle() = ReadObjectImpl(as_reference);
result.SetAt(i, *PassiveObjectHandle());
}
}
MessageSnapshotReader::MessageSnapshotReader(Message* message, Thread* thread)
: SnapshotReader(message->snapshot(),
message->snapshot_length(),
Snapshot::kMessage,
new ZoneGrowableArray<BackRefNode>(kNumInitialReferences),
thread),
finalizable_data_(message->finalizable_data()) {}
MessageSnapshotReader::~MessageSnapshotReader() {
ResetBackwardReferenceTable();
}
SnapshotWriter::SnapshotWriter(Thread* thread,
Snapshot::Kind kind,
ReAlloc alloc,
DeAlloc dealloc,
intptr_t initial_size,
ForwardList* forward_list,
bool can_send_any_object)
: BaseWriter(alloc, dealloc, initial_size),
thread_(thread),
kind_(kind),
object_store_(isolate()->object_store()),
class_table_(isolate()->class_table()),
forward_list_(forward_list),
exception_type_(Exceptions::kNone),
exception_msg_(NULL),
can_send_any_object_(can_send_any_object) {
ASSERT(forward_list_ != NULL);
}
void SnapshotWriter::WriteObject(ObjectPtr rawobj) {
WriteObjectImpl(rawobj, kAsInlinedObject);
WriteForwardedObjects();
}
uint32_t SnapshotWriter::GetObjectTags(ObjectPtr raw) {
return raw->ptr()->tags_;
}
uint32_t SnapshotWriter::GetObjectTags(ObjectLayout* raw) {
return raw->tags_;
}
uword SnapshotWriter::GetObjectTagsAndHash(ObjectPtr raw) {
uword result = raw->ptr()->tags_;
#if defined(HASH_IN_OBJECT_HEADER)
result |= static_cast<uword>(raw->ptr()->hash_) << 32;
#endif
return result;
}
#define VM_OBJECT_CLASS_LIST(V) \
V(OneByteString) \
V(TwoByteString) \
V(Mint) \
V(Double) \
V(ImmutableArray)
#define VM_OBJECT_WRITE(clazz) \
case clazz::kClassId: { \
object_id = forward_list_->AddObject(zone(), rawobj, kIsSerialized); \
clazz##Ptr raw_obj = static_cast<clazz##Ptr>(rawobj); \
raw_obj->ptr()->WriteTo(this, object_id, kind(), false); \
return true; \
}
#define WRITE_VM_SINGLETON_OBJ(obj, id) \
if (rawobj == obj) { \
WriteVMIsolateObject(id); \
return true; \
}
bool SnapshotWriter::HandleVMIsolateObject(ObjectPtr rawobj) {
// Check if it is one of the singleton VM objects.
WRITE_VM_SINGLETON_OBJ(Object::null(), kNullObject);
WRITE_VM_SINGLETON_OBJ(Object::sentinel().raw(), kSentinelObject);
WRITE_VM_SINGLETON_OBJ(Object::transition_sentinel().raw(),
kTransitionSentinelObject);
WRITE_VM_SINGLETON_OBJ(Object::empty_array().raw(), kEmptyArrayObject);
WRITE_VM_SINGLETON_OBJ(Object::zero_array().raw(), kZeroArrayObject);
WRITE_VM_SINGLETON_OBJ(Object::dynamic_type().raw(), kDynamicType);
WRITE_VM_SINGLETON_OBJ(Object::void_type().raw(), kVoidType);
WRITE_VM_SINGLETON_OBJ(Object::empty_type_arguments().raw(),
kEmptyTypeArguments);
WRITE_VM_SINGLETON_OBJ(Bool::True().raw(), kTrueValue);
WRITE_VM_SINGLETON_OBJ(Bool::False().raw(), kFalseValue);
WRITE_VM_SINGLETON_OBJ(Object::extractor_parameter_types().raw(),
kExtractorParameterTypes);
WRITE_VM_SINGLETON_OBJ(Object::extractor_parameter_names().raw(),
kExtractorParameterNames);
WRITE_VM_SINGLETON_OBJ(Object::empty_context_scope().raw(),
kEmptyContextScopeObject);
WRITE_VM_SINGLETON_OBJ(Object::empty_object_pool().raw(), kEmptyObjectPool);
WRITE_VM_SINGLETON_OBJ(Object::empty_descriptors().raw(), kEmptyDescriptors);
WRITE_VM_SINGLETON_OBJ(Object::empty_var_descriptors().raw(),
kEmptyVarDescriptors);
WRITE_VM_SINGLETON_OBJ(Object::empty_exception_handlers().raw(),
kEmptyExceptionHandlers);
// Check if it is a singleton class object which is shared by
// all isolates.
intptr_t id = rawobj->GetClassId();
if (id == kClassCid) {
ClassPtr raw_class = static_cast<ClassPtr>(rawobj);
intptr_t class_id = raw_class->ptr()->id_;
if (IsSingletonClassId(class_id)) {
intptr_t object_id = ObjectIdFromClassId(class_id);
WriteVMIsolateObject(object_id);
return true;
}
}
// Check if it is a singleton Argument descriptor object.
for (intptr_t i = 0; i < ArgumentsDescriptor::kCachedDescriptorCount; i++) {
if (rawobj == ArgumentsDescriptor::cached_args_descriptors_[i]) {
WriteVMIsolateObject(kCachedArgumentsDescriptor0 + i);
return true;
}
}
// Check if it is a singleton ICData array object.
for (intptr_t i = 0; i < ICData::kCachedICDataArrayCount; i++) {
if (rawobj == ICData::cached_icdata_arrays_[i]) {
WriteVMIsolateObject(kCachedICDataArray0 + i);
return true;
}
}
// In the case of script snapshots or for messages we do not use
// the index into the vm isolate snapshot object table, instead we
// explicitly write the object out.
intptr_t object_id = forward_list_->FindObject(rawobj);
if (object_id != -1) {
WriteIndexedObject(object_id);
return true;
} else {
// We do this check down here, because it's quite expensive.
if (!rawobj->ptr()->InVMIsolateHeap()) {
return false;
}
switch (id) {
VM_OBJECT_CLASS_LIST(VM_OBJECT_WRITE)
case kTypedDataUint32ArrayCid: {
object_id = forward_list_->AddObject(zone(), rawobj, kIsSerialized);
TypedDataPtr raw_obj = static_cast<TypedDataPtr>(rawobj);
raw_obj->ptr()->WriteTo(this, object_id, kind(), false);
return true;
}
default:
OS::PrintErr("class id = %" Pd "\n", id);
break;
}
}
const Object& obj = Object::Handle(rawobj);
FATAL1("Unexpected reference to object in VM isolate: %s\n", obj.ToCString());
return false;
}
#undef VM_OBJECT_WRITE
ForwardList::ForwardList(Thread* thread, intptr_t first_object_id)
: thread_(thread),
first_object_id_(first_object_id),
nodes_(),
first_unprocessed_object_id_(first_object_id) {
ASSERT(first_object_id > 0);
isolate()->set_forward_table_new(new WeakTable());
isolate()->set_forward_table_old(new WeakTable());
}
ForwardList::~ForwardList() {
isolate()->set_forward_table_new(nullptr);
isolate()->set_forward_table_old(nullptr);
}
intptr_t ForwardList::AddObject(Zone* zone,
ObjectPtr raw,
SerializeState state) {
NoSafepointScope no_safepoint;
intptr_t object_id = next_object_id();
ASSERT(object_id > 0 && object_id <= kMaxObjectId);
const Object& obj = Object::ZoneHandle(zone, raw);
Node* node = new Node(&obj, state);
ASSERT(node != NULL);
nodes_.Add(node);
ASSERT(object_id != 0);
SetObjectId(raw, object_id);
return object_id;
}
intptr_t ForwardList::FindObject(ObjectPtr raw) {
NoSafepointScope no_safepoint;
intptr_t id = GetObjectId(raw);
ASSERT(id == 0 || NodeForObjectId(id)->obj()->raw() == raw);
return (id == 0) ? static_cast<intptr_t>(kInvalidIndex) : id;
}
void ForwardList::SetObjectId(ObjectPtr object, intptr_t id) {
if (object->IsNewObject()) {
isolate()->forward_table_new()->SetValueExclusive(object, id);
} else {
isolate()->forward_table_old()->SetValueExclusive(object, id);
}
}
intptr_t ForwardList::GetObjectId(ObjectPtr object) {
if (object->IsNewObject()) {
return isolate()->forward_table_new()->GetValueExclusive(object);
} else {
return isolate()->forward_table_old()->GetValueExclusive(object);
}
}
bool SnapshotWriter::CheckAndWritePredefinedObject(ObjectPtr rawobj) {
// Check if object can be written in one of the following ways:
// - Smi: the Smi value is written as is (last bit is not tagged).
// - VM internal class (from VM isolate): (index of class in vm isolate | 0x3)
// - Object that has already been written: (negative id in stream | 0x3)
NoSafepointScope no_safepoint;
// First check if it is a Smi (i.e not a heap object).
if (!rawobj->IsHeapObject()) {
Write<int64_t>(static_cast<intptr_t>(rawobj));
return true;
}
intptr_t cid = rawobj->GetClassId();
if ((kind_ == Snapshot::kMessage) && (cid == kDoubleCid)) {
WriteVMIsolateObject(kDoubleObject);
DoublePtr rd = static_cast<DoublePtr>(rawobj);
WriteDouble(rd->ptr()->value_);
return true;
}
// Check if object has already been serialized, in that case just write
// the object id out.
intptr_t object_id = forward_list_->FindObject(rawobj);
if (object_id != kInvalidIndex) {
WriteIndexedObject(object_id);
return true;
}
// Check if it is a code object in that case just write a Null object
// as we do not want code objects in the snapshot.
if ((cid == kCodeCid) || (cid == kBytecodeCid)) {
WriteVMIsolateObject(kNullObject);
return true;
}
// Now check if it is an object from the VM isolate. These objects are shared
// by all isolates.
if (HandleVMIsolateObject(rawobj)) {
return true;
}
// Check if classes are not being serialized and it is preinitialized type
// or a predefined internal VM class in the object store.
// Check if it is an internal VM class which is in the object store.
if (cid == kClassCid) {
ClassPtr raw_class = static_cast<ClassPtr>(rawobj);
intptr_t class_id = raw_class->ptr()->id_;
if (IsBootstrapedClassId(class_id)) {
intptr_t object_id = ObjectIdFromClassId(class_id);
WriteIndexedObject(object_id);
return true;
}
}
// Now check it is a preinitialized type object.
intptr_t index = GetTypeIndex(object_store(), rawobj);
if (index != kInvalidIndex) {
WriteIndexedObject(index);
return true;
}
return false;
}
void SnapshotWriter::WriteObjectImpl(ObjectPtr raw, bool as_reference) {
// First check if object can be written as a simple predefined type.
if (CheckAndWritePredefinedObject(raw)) {
return;
}
// When we know that we are dealing with leaf or shallow objects we write
// these objects inline even when 'as_reference' is true.
const bool write_as_reference = as_reference && !raw->ptr()->IsCanonical();
uintptr_t tags = GetObjectTagsAndHash(raw);
// Add object to the forward ref list and mark it so that future references
// to this object in the snapshot will use this object id. Mark the
// serialization state so that we do the right thing when we go through
// the forward list.
intptr_t class_id = raw->GetClassId();
intptr_t object_id;
if (write_as_reference && IsSplitClassId(class_id)) {
object_id = forward_list_->AddObject(zone(), raw, kIsNotSerialized);
} else {
object_id = forward_list_->AddObject(zone(), raw, kIsSerialized);
}
if (write_as_reference || !IsSplitClassId(class_id)) {
object_id = kOmittedObjectId;
}
WriteMarkedObjectImpl(raw, tags, object_id, write_as_reference);
}
void SnapshotWriter::WriteMarkedObjectImpl(ObjectPtr raw,
intptr_t tags,
intptr_t object_id,
bool as_reference) {
NoSafepointScope no_safepoint;
ClassPtr cls = class_table_->At(ObjectLayout::ClassIdTag::decode(tags));
intptr_t class_id = cls->ptr()->id_;
ASSERT(class_id == ObjectLayout::ClassIdTag::decode(tags));
if (class_id >= kNumPredefinedCids || IsImplicitFieldClassId(class_id)) {
WriteInstance(raw, cls, tags, object_id, as_reference);
return;
}
switch (class_id) {
#define SNAPSHOT_WRITE(clazz) \
case clazz::kClassId: { \
clazz##Ptr raw_obj = static_cast<clazz##Ptr>(raw); \
raw_obj->ptr()->WriteTo(this, object_id, kind_, as_reference); \
return; \
}
CLASS_LIST_NO_OBJECT(SNAPSHOT_WRITE)
#undef SNAPSHOT_WRITE
#define SNAPSHOT_WRITE(clazz) case kTypedData##clazz##Cid:
CLASS_LIST_TYPED_DATA(SNAPSHOT_WRITE) {
TypedDataPtr raw_obj = static_cast<TypedDataPtr>(raw);
raw_obj->ptr()->WriteTo(this, object_id, kind_, as_reference);
return;
}
#undef SNAPSHOT_WRITE
#define SNAPSHOT_WRITE(clazz) case kExternalTypedData##clazz##Cid:
CLASS_LIST_TYPED_DATA(SNAPSHOT_WRITE) {
ExternalTypedDataPtr raw_obj = static_cast<ExternalTypedDataPtr>(raw);
raw_obj->ptr()->WriteTo(this, object_id, kind_, as_reference);
return;
}
#undef SNAPSHOT_WRITE
#define SNAPSHOT_WRITE(clazz) case kTypedData##clazz##ViewCid:
case kByteDataViewCid:
CLASS_LIST_TYPED_DATA(SNAPSHOT_WRITE) {
auto raw_obj = static_cast<TypedDataViewPtr>(raw);
raw_obj->ptr()->WriteTo(this, object_id, kind_, as_reference);
return;
}
#undef SNAPSHOT_WRITE
#define SNAPSHOT_WRITE(clazz) case kFfi##clazz##Cid:
CLASS_LIST_FFI(SNAPSHOT_WRITE) {
SetWriteException(Exceptions::kArgument,
"Native objects (from dart:ffi) such as Pointers and "
"Structs cannot be passed between isolates.");
UNREACHABLE();
}
#undef SNAPSHOT_WRITE
default:
break;
}
const Object& obj = Object::Handle(raw);
FATAL1("Unexpected object: %s\n", obj.ToCString());
}
class WriteInlinedObjectVisitor : public ObjectVisitor {
public:
explicit WriteInlinedObjectVisitor(SnapshotWriter* writer)
: writer_(writer) {}
virtual void VisitObject(ObjectPtr obj) {
intptr_t object_id = writer_->forward_list_->FindObject(obj);
ASSERT(object_id != kInvalidIndex);
intptr_t tags = MessageWriter::GetObjectTagsAndHash(ObjectPtr(obj));
writer_->WriteMarkedObjectImpl(obj, tags, object_id, kAsInlinedObject);
}
private:
SnapshotWriter* writer_;
};
void SnapshotWriter::WriteForwardedObjects() {
WriteInlinedObjectVisitor visitor(this);
forward_list_->SerializeAll(&visitor);
}
void ForwardList::SerializeAll(ObjectVisitor* writer) {
// Write out all objects that were added to the forward list and have
// not been serialized yet. These would typically be fields of instance
// objects, arrays or immutable arrays (this is done in order to avoid
// deep recursive calls to WriteObjectImpl).
// NOTE: The forward list might grow as we process the list.
#ifdef DEBUG
for (intptr_t i = first_object_id(); i < first_unprocessed_object_id_; ++i) {
ASSERT(NodeForObjectId(i)->is_serialized());
}
#endif // DEBUG
for (intptr_t id = first_unprocessed_object_id_; id < next_object_id();
++id) {
if (!NodeForObjectId(id)->is_serialized()) {
// Write the object out in the stream.
ObjectPtr raw = NodeForObjectId(id)->obj()->raw();
writer->VisitObject(raw);
// Mark object as serialized.
NodeForObjectId(id)->set_state(kIsSerialized);
}
}
first_unprocessed_object_id_ = next_object_id();
}
void SnapshotWriter::WriteClassId(ClassLayout* cls) {
ASSERT(!Snapshot::IsFull(kind_));
int class_id = cls->id_;
ASSERT(!IsSingletonClassId(class_id) && !IsBootstrapedClassId(class_id));
// Write out the library url and class name.
LibraryPtr library = cls->library_;
ASSERT(library != Library::null());
WriteObjectImpl(library->ptr()->url_, kAsInlinedObject);
WriteObjectImpl(cls->name_, kAsInlinedObject);
}
void SnapshotWriter::WriteStaticImplicitClosure(intptr_t object_id,
FunctionPtr func,
intptr_t tags) {
// Write out the serialization header value for this object.
WriteInlinedObjectHeader(object_id);
// Indicate this is a static implicit closure object.
Write<int32_t>(SerializedHeaderData::encode(kStaticImplicitClosureObjectId));
// Write out the tags.
WriteTags(tags);
// Write out the library url, class name and signature function name.
ClassPtr cls = GetFunctionOwner(func);
ASSERT(cls != Class::null());
LibraryPtr library = cls->ptr()->library_;
ASSERT(library != Library::null());
WriteObjectImpl(library->ptr()->url_, kAsInlinedObject);
WriteObjectImpl(cls->ptr()->name_, kAsInlinedObject);
WriteObjectImpl(func->ptr()->name_, kAsInlinedObject);
}
void SnapshotWriter::ArrayWriteTo(intptr_t object_id,
intptr_t array_kind,
intptr_t tags,
SmiPtr length,
TypeArgumentsPtr type_arguments,
ObjectPtr data[],
bool as_reference) {
if (as_reference) {
// Write out the serialization header value for this object.
WriteInlinedObjectHeader(kOmittedObjectId);
// Write out the class information.
WriteIndexedObject(array_kind);
WriteTags(tags);
// Write out the length field.
Write<ObjectPtr>(length);
} else {
intptr_t len = Smi::Value(length);
// Write out the serialization header value for this object.
WriteInlinedObjectHeader(object_id);
// Write out the class and tags information.
WriteIndexedObject(array_kind);
WriteTags(tags);
// Write out the length field.
Write<ObjectPtr>(length);
// Write out the type arguments.
WriteObjectImpl(type_arguments, kAsInlinedObject);
// Write out the individual object ids.
bool write_as_reference = ObjectLayout::IsCanonical(tags) ? false : true;
for (intptr_t i = 0; i < len; i++) {
WriteObjectImpl(data[i], write_as_reference);
}
}
}
FunctionPtr SnapshotWriter::IsSerializableClosure(ClosurePtr closure) {
// Extract the function object to check if this closure
// can be sent in an isolate message.
FunctionPtr func = closure->ptr()->function_;
// We only allow closure of top level methods or static functions in a
// class to be sent in isolate messages.
if (can_send_any_object() &&
Function::IsImplicitStaticClosureFunction(func)) {
return func;
}
// Not a closure of a top level method or static function, throw an
// exception as we do not allow these objects to be serialized.
HANDLESCOPE(thread());
const Function& errorFunc = Function::Handle(zone(), func);
ASSERT(!errorFunc.IsNull());
// All other closures are errors.
char* chars = OS::SCreate(
thread()->zone(),
"Illegal argument in isolate message : (object is a closure - %s)",
errorFunc.ToCString());
SetWriteException(Exceptions::kArgument, chars);
return Function::null();
}
ClassPtr SnapshotWriter::GetFunctionOwner(FunctionPtr func) {
ObjectPtr owner = func->ptr()->owner_;
uint32_t tags = GetObjectTags(owner);
intptr_t class_id = ObjectLayout::ClassIdTag::decode(tags);
if (class_id == kClassCid) {
return static_cast<ClassPtr>(owner);
}
ASSERT(class_id == kPatchClassCid);
return static_cast<PatchClassPtr>(owner)->ptr()->patched_class_;
}
void SnapshotWriter::CheckForNativeFields(ClassPtr cls) {
if (cls->ptr()->num_native_fields_ != 0) {
// We do not allow objects with native fields in an isolate message.
HANDLESCOPE(thread());
const Class& clazz = Class::Handle(zone(), cls);
char* chars = OS::SCreate(thread()->zone(),
"Illegal argument in isolate message"
" : (object extends NativeWrapper - %s)",
clazz.ToCString());
SetWriteException(Exceptions::kArgument, chars);
}
}
void SnapshotWriter::SetWriteException(Exceptions::ExceptionType type,
const char* msg) {
set_exception_type(type);
set_exception_msg(msg);
// The more specific error is set up in SnapshotWriter::ThrowException().
thread()->long_jump_base()->Jump(1, Object::snapshot_writer_error());
}
void SnapshotWriter::WriteInstance(ObjectPtr raw,
ClassPtr cls,
intptr_t tags,
intptr_t object_id,
bool as_reference) {
// Closure instances are handled by ClosureLayout::WriteTo().
ASSERT(!Class::IsClosureClass(cls));
// Check if the instance has native fields and throw an exception if it does.
CheckForNativeFields(cls);
// Object is regular dart instance.
if (as_reference) {
// Write out the serialization header value for this object.
WriteInlinedObjectHeader(kOmittedObjectId);
// Indicate this is an instance object.
Write<int32_t>(SerializedHeaderData::encode(kInstanceObjectId));
WriteTags(tags);
// Write out the class information for this object.
WriteObjectImpl(cls, kAsInlinedObject);
} else {
intptr_t next_field_offset = Class::host_next_field_offset_in_words(cls)
<< kWordSizeLog2;
ASSERT(next_field_offset > 0);
// Write out the serialization header value for this object.
WriteInlinedObjectHeader(object_id);
// Indicate this is an instance object.
Write<int32_t>(SerializedHeaderData::encode(kInstanceObjectId));
// Write out the tags.
WriteTags(tags);
// Write out the class information for this object.
WriteObjectImpl(cls, kAsInlinedObject);
const auto unboxed_fields =
isolate()->group()->shared_class_table()->GetUnboxedFieldsMapAt(
cls->ptr()->id_);
// Write out all the fields for the object.
// Instance::NextFieldOffset() returns the offset of the first field in
// a Dart object.
bool write_as_reference = ObjectLayout::IsCanonical(tags) ? false : true;
intptr_t offset = Instance::NextFieldOffset();
while (offset < next_field_offset) {
if (unboxed_fields.Get(offset / kWordSize)) {
// Writes 32 bits of the unboxed value at a time
const uword value = *reinterpret_cast<uword*>(
reinterpret_cast<uword>(raw->ptr()) + offset);
WriteWordWith32BitWrites(value);
} else {
ObjectPtr raw_obj = *reinterpret_cast<ObjectPtr*>(
reinterpret_cast<uword>(raw->ptr()) + offset);
WriteObjectImpl(raw_obj, write_as_reference);
}
offset += kWordSize;
}
}
return;
}
bool SnapshotWriter::AllowObjectsInDartLibrary(LibraryPtr library) {
return (library == object_store()->collection_library() ||
library == object_store()->core_library() ||
library == object_store()->typed_data_library());
}
intptr_t SnapshotWriter::FindVmSnapshotObject(ObjectPtr rawobj) {
intptr_t length = Object::vm_isolate_snapshot_object_table().Length();
for (intptr_t i = 0; i < length; i++) {
if (Object::vm_isolate_snapshot_object_table().At(i) == rawobj) {
return (i + kMaxPredefinedObjectIds);
}
}
return kInvalidIndex;
}
void SnapshotWriter::ThrowException(Exceptions::ExceptionType type,
const char* msg) {
{
NoSafepointScope no_safepoint;
ErrorPtr error = thread()->StealStickyError();
ASSERT(error == Object::snapshot_writer_error().raw());
}
if (msg != NULL) {
const String& msg_obj = String::Handle(String::New(msg));
const Array& args = Array::Handle(Array::New(1));
args.SetAt(0, msg_obj);
Exceptions::ThrowByType(type, args);
} else {
Exceptions::ThrowByType(type, Object::empty_array());
}
UNREACHABLE();
}
void SnapshotWriter::WriteVersionAndFeatures() {
const char* expected_version = Version::SnapshotString();
ASSERT(expected_version != NULL);
const intptr_t version_len = strlen(expected_version);
WriteBytes(reinterpret_cast<const uint8_t*>(expected_version), version_len);
const char* expected_features =
Dart::FeaturesString(Isolate::Current(), false, kind_);
ASSERT(expected_features != NULL);
const intptr_t features_len = strlen(expected_features);
WriteBytes(reinterpret_cast<const uint8_t*>(expected_features),
features_len + 1);
free(const_cast<char*>(expected_features));
}
void SnapshotWriterVisitor::VisitPointers(ObjectPtr* first, ObjectPtr* last) {
ASSERT(Utils::IsAligned(first, sizeof(*first)));
ASSERT(Utils::IsAligned(last, sizeof(*last)));
for (ObjectPtr* current = first; current <= last; current++) {
ObjectPtr raw_obj = *current;
writer_->WriteObjectImpl(raw_obj, as_references_);
}
}
static uint8_t* malloc_allocator(uint8_t* ptr,
intptr_t old_size,
intptr_t new_size) {
void* new_ptr = realloc(reinterpret_cast<void*>(ptr), new_size);
return reinterpret_cast<uint8_t*>(new_ptr);
}
static void malloc_deallocator(uint8_t* ptr) {
free(reinterpret_cast<void*>(ptr));
}
MessageWriter::MessageWriter(bool can_send_any_object)
: SnapshotWriter(Thread::Current(),
Snapshot::kMessage,
malloc_allocator,
malloc_deallocator,
kInitialSize,
&forward_list_,
can_send_any_object),
forward_list_(thread(), kMaxPredefinedObjectIds),
finalizable_data_(new MessageFinalizableData()) {}
MessageWriter::~MessageWriter() {
delete finalizable_data_;
}
std::unique_ptr<Message> MessageWriter::WriteMessage(
const Object& obj,
Dart_Port dest_port,
Message::Priority priority) {
ASSERT(kind() == Snapshot::kMessage);
ASSERT(isolate() != NULL);
// Setup for long jump in case there is an exception while writing
// the message.
volatile bool has_exception = false;
{
LongJumpScope jump;
if (setjmp(*jump.Set()) == 0) {
NoSafepointScope no_safepoint;
WriteObject(obj.raw());
} else {
FreeBuffer();
has_exception = true;
}
}
if (has_exception) {
ThrowException(exception_type(), exception_msg());
} else {
finalizable_data_->SerializationSucceeded();
}
MessageFinalizableData* finalizable_data = finalizable_data_;
finalizable_data_ = NULL;
return Message::New(dest_port, buffer(), BytesWritten(), finalizable_data,
priority);
}
} // namespace dart