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dart / sdk.git / refs/tags/1.22.0-dev.10.4 / . / 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/dart_entry.h"
#include "vm/exceptions.h"
#include "vm/heap.h"
#include "vm/lockers.h"
#include "vm/longjump.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/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 = 64;
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 >= kNullCid && class_id <= kVoidCid));
}
static bool IsObjectStoreClassId(intptr_t class_id) {
// Check if this is a class which is stored in the object store.
return (class_id == kObjectCid ||
(class_id >= kInstanceCid && class_id <= kUserTagCid) ||
class_id == kArrayCid || class_id == kImmutableArrayCid ||
RawObject::IsStringClassId(class_id) ||
RawObject::IsTypedDataClassId(class_id) ||
RawObject::IsExternalTypedDataClassId(class_id) ||
class_id == kNullCid);
}
static bool IsObjectStoreTypeId(intptr_t index) {
// Check if this is a type which is stored in the object store.
return (index >= kObjectType && index <= kArrayType);
}
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 ||
RawObject::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));
ASSERT(!(RawObject::IsImplicitFieldClassId(class_id)));
return (class_id + kClassIdsOffset);
}
static RawType* GetType(ObjectStore* object_store, intptr_t index) {
switch (index) {
case kObjectType:
return object_store->object_type();
case kNullType:
return object_store->null_type();
case kFunctionType:
return object_store->function_type();
case kNumberType:
return object_store->number_type();
case kSmiType:
return object_store->smi_type();
case kMintType:
return object_store->mint_type();
case kDoubleType:
return object_store->double_type();
case kIntType:
return object_store->int_type();
case kBoolType:
return object_store->bool_type();
case kStringType:
return object_store->string_type();
case kArrayType:
return object_store->array_type();
default:
break;
}
UNREACHABLE();
return Type::null();
}
static intptr_t GetTypeIndex(ObjectStore* object_store,
const RawType* raw_type) {
ASSERT(raw_type->IsHeapObject());
if (raw_type == object_store->object_type()) {
return kObjectType;
} else if (raw_type == object_store->null_type()) {
return kNullType;
} else if (raw_type == object_store->function_type()) {
return kFunctionType;
} else if (raw_type == object_store->number_type()) {
return kNumberType;
} else if (raw_type == object_store->smi_type()) {
return kSmiType;
} else if (raw_type == object_store->mint_type()) {
return kMintType;
} else if (raw_type == object_store->double_type()) {
return kDoubleType;
} else if (raw_type == object_store->int_type()) {
return kIntType;
} else if (raw_type == object_store->bool_type()) {
return kBoolType;
} else if (raw_type == object_store->string_type()) {
return kStringType;
} else if (raw_type == object_store->array_type()) {
return kArrayType;
}
return kInvalidIndex;
}
const char* Snapshot::KindToCString(Kind kind) {
switch (kind) {
case kCore:
return "core";
case kScript:
return "script";
case kMessage:
return "message";
case kAppJIT:
return "app-jit";
case kAppAOT:
return "app-aot";
case kNone:
return "none";
case kInvalid:
default:
return "invalid";
}
}
// TODO(5411462): Temporary setup of snapshot for testing purposes,
// the actual creation of a snapshot maybe done differently.
const Snapshot* Snapshot::SetupFromBuffer(const void* raw_memory) {
ASSERT(raw_memory != NULL);
ASSERT(kHeaderSize == sizeof(Snapshot));
ASSERT(kLengthIndex == length_offset());
ASSERT((kSnapshotFlagIndex * sizeof(int64_t)) == kind_offset());
ASSERT((kHeapObjectTag & kInlined));
const Snapshot* snapshot = reinterpret_cast<const Snapshot*>(raw_memory);
// If the raw length is negative or greater than what the local machine can
// handle, then signal an error.
int64_t snapshot_length = ReadUnaligned(&snapshot->unaligned_length_);
if ((snapshot_length < 0) || (snapshot_length > kIntptrMax)) {
return NULL;
}
return snapshot;
}
RawSmi* BaseReader::ReadAsSmi() {
intptr_t value = Read<int32_t>();
ASSERT((value & kSmiTagMask) == kSmiTag);
return reinterpret_cast<RawSmi*>(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_)),
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_)),
stream_(TokenStream::Handle(zone_)),
data_(ExternalTypedData::Handle(zone_)),
typed_data_(TypedData::Handle(zone_)),
function_(Function::Handle(zone_)),
error_(UnhandledException::Handle(zone_)),
max_vm_isolate_object_id_(
(Snapshot::IsFull(kind))
? Object::vm_isolate_snapshot_object_table().Length()
: 0),
backward_references_(backward_refs) {}
RawObject* 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);
}
}
ProcessDeferredCanonicalizations();
return obj.raw();
} else {
// An error occurred while reading, return the error object.
const Error& err = Error::Handle(thread()->sticky_error());
thread()->clear_sticky_error();
return err.raw();
}
}
RawClass* 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) ||
!IsObjectStoreClassId(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, kInvalidPatchIndex, 0);
library_ = Library::LookupLibrary(thread(), str_);
if (library_.IsNull() || !library_.Loaded()) {
SetReadException("Invalid object found in message.");
}
str_ ^= ReadObjectImpl(kAsInlinedObject);
cls = library_.LookupClassAllowPrivate(str_);
if (cls.IsNull()) {
SetReadException("Invalid object found in message.");
}
cls.EnsureIsFinalized(thread());
return cls.raw();
}
RawFunction* SnapshotReader::ReadFunctionId(intptr_t object_id) {
ASSERT(kind_ == Snapshot::kScript);
// Read the function header information and lookup the function.
intptr_t func_header = Read<int32_t>();
ASSERT((func_header & kSmiTagMask) != kSmiTag);
ASSERT(!IsVMIsolateObject(func_header) ||
!IsSingletonClassId(GetVMIsolateObjectId(func_header)));
ASSERT((SerializedHeaderTag::decode(func_header) != kObjectId) ||
!IsObjectStoreClassId(SerializedHeaderData::decode(func_header)));
Function& func = Function::ZoneHandle(zone(), Function::null());
AddBackRef(object_id, &func, kIsDeserialized);
// Read the library/class/function information and lookup the function.
str_ ^= ReadObjectImpl(func_header, kAsInlinedObject, kInvalidPatchIndex, 0);
library_ = Library::LookupLibrary(thread(), str_);
if (library_.IsNull() || !library_.Loaded()) {
SetReadException("Expected a library name, but found an invalid name.");
}
str_ ^= ReadObjectImpl(kAsInlinedObject);
if (str_.Equals(Symbols::TopLevel(), 0, Symbols::TopLevel().Length())) {
str_ ^= ReadObjectImpl(kAsInlinedObject);
func ^= library_.LookupLocalFunction(str_);
} else {
cls_ = library_.LookupClassAllowPrivate(str_);
if (cls_.IsNull()) {
SetReadException("Expected a class name, but found an invalid name.");
}
cls_.EnsureIsFinalized(thread());
str_ ^= ReadObjectImpl(kAsInlinedObject);
func ^= cls_.LookupFunctionAllowPrivate(str_);
}
if (func.IsNull()) {
SetReadException("Expected a function name, but found an invalid name.");
}
return func.raw();
}
RawObject* 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.
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);
func = library_.LookupFunctionAllowPrivate(str_);
} else {
cls_ = library_.LookupClassAllowPrivate(str_);
if (cls_.IsNull()) {
OS::Print("Name of class not found %s\n", str_.ToCString());
SetReadException("Invalid Class object found in message.");
}
cls_.EnsureIsFinalized(thread());
str_ ^= ReadObjectImpl(kAsInlinedObject);
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);
}
RawObject* 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();
}
RawObject* SnapshotReader::ReadObjectImpl(bool as_reference,
intptr_t patch_object_id,
intptr_t patch_offset) {
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,
patch_object_id, patch_offset);
}
RawObject* SnapshotReader::ReadObjectImpl(intptr_t header_value,
bool as_reference,
intptr_t patch_object_id,
intptr_t patch_offset) {
if (IsVMIsolateObject(header_value)) {
return ReadVMIsolateObject(header_value);
}
if (SerializedHeaderTag::decode(header_value) == kObjectId) {
return ReadIndexedObject(SerializedHeaderData::decode(header_value),
patch_object_id, patch_offset);
}
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 && !RawObject::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 = RawObject::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 = RawObject::ClassIdTag::update(class_id, tags);
pobj_ = ExternalTypedData::ReadFrom(this, object_id, tags, kind_, true);
break;
}
#undef SNAPSHOT_READ
default:
UNREACHABLE();
break;
}
if (!read_as_reference) {
AddPatchRecord(object_id, patch_object_id, patch_offset);
}
return pobj_.raw();
}
RawObject* 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_.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_SPACE(kind_));
} else {
cls_ ^= ReadObjectImpl(kAsInlinedObject);
ASSERT(!cls_.IsNull());
instance_size = cls_.instance_size();
}
if (!as_reference) {
// Read all the individual fields for inlined objects.
intptr_t next_field_offset = cls_.next_field_offset();
intptr_t type_argument_field_offset = cls_.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 = RawObject::IsCanonical(tags) ? false : true;
intptr_t offset = Instance::NextFieldOffset();
intptr_t result_cid = result->GetClassId();
while (offset < next_field_offset) {
pobj_ = ReadObjectImpl(read_as_reference);
result->SetFieldAtOffset(offset, pobj_);
if ((offset != type_argument_field_offset) &&
(kind_ == Snapshot::kMessage) && FLAG_use_field_guards) {
// 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_.Offset() == 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 (RawObject::IsCanonical(tags)) {
*result = result->CheckAndCanonicalize(thread(), NULL);
ASSERT(!result->IsNull());
}
}
return result->raw();
}
void SnapshotReader::AddBackRef(intptr_t id,
Object* obj,
DeserializeState state,
bool defer_canonicalization) {
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, defer_canonicalization);
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;
}
class HeapLocker : public StackResource {
public:
HeapLocker(Thread* thread, PageSpace* page_space)
: StackResource(thread), page_space_(page_space) {
page_space_->AcquireDataLock();
}
~HeapLocker() { page_space_->ReleaseDataLock(); }
private:
PageSpace* page_space_;
};
RawObject* SnapshotReader::ReadScriptSnapshot() {
ASSERT(kind_ == Snapshot::kScript);
// First read the version string, and check that it matches.
RawApiError* error = VerifyVersionAndFeatures();
if (error != ApiError::null()) {
return error;
}
// The version string matches. Read the rest of the snapshot.
obj_ = ReadObject();
if (!obj_.IsLibrary()) {
if (!obj_.IsError()) {
const intptr_t kMessageBufferSize = 128;
char message_buffer[kMessageBufferSize];
OS::SNPrint(message_buffer, kMessageBufferSize,
"Invalid object %s found in script snapshot",
obj_.ToCString());
const String& msg = String::Handle(String::New(message_buffer));
obj_ = ApiError::New(msg);
}
}
return obj_.raw();
}
RawApiError* SnapshotReader::VerifyVersionAndFeatures() {
// 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];
OS::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)) {
const intptr_t kMessageBufferSize = 256;
char message_buffer[kMessageBufferSize];
char* actual_version = OS::StrNDup(version, version_len);
OS::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(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 = OS::StrNLen(features, PendingBytes());
if ((buffer_len != expected_len) ||
strncmp(features, expected_features, expected_len)) {
const intptr_t kMessageBufferSize = 256;
char message_buffer[kMessageBufferSize];
char* actual_features =
OS::StrNDup(features, buffer_len < 128 ? buffer_len : 128);
OS::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();
}
RawObject* 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);
}
int32_t ImageWriter::GetOffsetFor(RawInstructions* instructions,
RawCode* code) {
#if defined(PRODUCT)
// Instructions are only dedup in product mode because it obfuscates profiler
// results.
for (intptr_t i = 0; i < instructions_.length(); i++) {
if (instructions_[i].raw_insns_ == instructions) {
return instructions_[i].offset_;
}
}
#endif
intptr_t heap_size = instructions->Size();
intptr_t offset = next_offset_;
next_offset_ += heap_size;
instructions_.Add(InstructionsData(instructions, code, offset));
return offset;
}
int32_t ImageWriter::GetObjectOffsetFor(RawObject* raw_object) {
intptr_t heap_size = raw_object->Size();
intptr_t offset = next_object_offset_;
next_object_offset_ += heap_size;
objects_.Add(ObjectData(raw_object));
return offset;
}
void ImageWriter::Write(WriteStream* clustered_stream, bool vm) {
Thread* thread = Thread::Current();
Zone* zone = thread->zone();
NOT_IN_PRODUCT(TimelineDurationScope tds(thread, Timeline::GetIsolateStream(),
"WriteInstructions"));
// Handlify collected raw pointers as building the names below
// will allocate on the Dart heap.
for (intptr_t i = 0; i < instructions_.length(); i++) {
InstructionsData& data = instructions_[i];
data.insns_ = &Instructions::Handle(zone, data.raw_insns_);
ASSERT(data.raw_code_ != NULL);
data.code_ = &Code::Handle(zone, data.raw_code_);
}
for (intptr_t i = 0; i < objects_.length(); i++) {
ObjectData& data = objects_[i];
data.obj_ = &Object::Handle(zone, data.raw_obj_);
}
// Append the direct-mapped RO data objects after the clustered snapshot.
WriteROData(clustered_stream);
WriteText(clustered_stream, vm);
}
void ImageWriter::WriteROData(WriteStream* stream) {
stream->Align(OS::kMaxPreferredCodeAlignment);
// Heap page starts here.
stream->WriteWord(next_object_offset_); // Data length.
COMPILE_ASSERT(OS::kMaxPreferredCodeAlignment >= kObjectAlignment);
stream->Align(OS::kMaxPreferredCodeAlignment);
// Heap page objects start here.
for (intptr_t i = 0; i < objects_.length(); i++) {
const Object& obj = *objects_[i].obj_;
NoSafepointScope no_safepoint;
uword start = reinterpret_cast<uword>(obj.raw()) - kHeapObjectTag;
uword end = start + obj.raw()->Size();
// Write object header with the mark and VM heap bits set.
uword marked_tags = obj.raw()->ptr()->tags_;
marked_tags = RawObject::VMHeapObjectTag::update(true, marked_tags);
marked_tags = RawObject::MarkBit::update(true, marked_tags);
stream->WriteWord(marked_tags);
start += sizeof(uword);
for (uword* cursor = reinterpret_cast<uword*>(start);
cursor < reinterpret_cast<uword*>(end); cursor++) {
stream->WriteWord(*cursor);
}
}
}
static void EnsureIdentifier(char* label) {
for (char c = *label; c != '\0'; c = *++label) {
if (((c >= 'a') && (c <= 'z')) || ((c >= 'A') && (c <= 'Z')) ||
((c >= '0') && (c <= '9'))) {
continue;
}
*label = '_';
}
}
void AssemblyImageWriter::WriteText(WriteStream* clustered_stream, bool vm) {
Zone* zone = Thread::Current()->zone();
const char* instructions_symbol =
vm ? "_kDartVmSnapshotInstructions" : "_kDartIsolateSnapshotInstructions";
assembly_stream_.Print(".text\n");
assembly_stream_.Print(".globl %s\n", instructions_symbol);
// Start snapshot at page boundary.
ASSERT(VirtualMemory::PageSize() >= OS::kMaxPreferredCodeAlignment);
assembly_stream_.Print(".balign %" Pd ", 0\n", VirtualMemory::PageSize());
assembly_stream_.Print("%s:\n", instructions_symbol);
// This head also provides the gap to make the instructions snapshot
// look like a HeapPage.
intptr_t instructions_length = next_offset_;
WriteWordLiteralText(instructions_length);
intptr_t header_words = Image::kHeaderSize / sizeof(uword);
for (intptr_t i = 1; i < header_words; i++) {
WriteWordLiteralText(0);
}
Object& owner = Object::Handle(zone);
String& str = String::Handle(zone);
for (intptr_t i = 0; i < instructions_.length(); i++) {
const Instructions& insns = *instructions_[i].insns_;
const Code& code = *instructions_[i].code_;
ASSERT(insns.raw()->Size() % sizeof(uint64_t) == 0);
// 1. Write from the header to the entry point.
{
NoSafepointScope no_safepoint;
uword beginning = reinterpret_cast<uword>(insns.raw_ptr());
uword entry = beginning + Instructions::HeaderSize();
ASSERT(Utils::IsAligned(beginning, sizeof(uint64_t)));
ASSERT(Utils::IsAligned(entry, sizeof(uint64_t)));
// Write Instructions with the mark and VM heap bits set.
uword marked_tags = insns.raw_ptr()->tags_;
marked_tags = RawObject::VMHeapObjectTag::update(true, marked_tags);
marked_tags = RawObject::MarkBit::update(true, marked_tags);
WriteWordLiteralText(marked_tags);
beginning += sizeof(uword);
for (uword* cursor = reinterpret_cast<uword*>(beginning);
cursor < reinterpret_cast<uword*>(entry); cursor++) {
WriteWordLiteralText(*cursor);
}
}
// 2. Write a label at the entry point.
owner = code.owner();
if (owner.IsNull()) {
const char* name = StubCode::NameOfStub(insns.UncheckedEntryPoint());
assembly_stream_.Print("Precompiled_Stub_%s:\n", name);
} else if (owner.IsClass()) {
str = Class::Cast(owner).Name();
const char* name = str.ToCString();
EnsureIdentifier(const_cast<char*>(name));
assembly_stream_.Print("Precompiled_AllocationStub_%s_%" Pd ":\n", name,
i);
} else if (owner.IsFunction()) {
const char* name = Function::Cast(owner).ToQualifiedCString();
EnsureIdentifier(const_cast<char*>(name));
assembly_stream_.Print("Precompiled_%s_%" Pd ":\n", name, i);
} else {
UNREACHABLE();
}
{
// 3. Write from the entry point to the end.
NoSafepointScope no_safepoint;
uword beginning = reinterpret_cast<uword>(insns.raw()) - kHeapObjectTag;
uword entry = beginning + Instructions::HeaderSize();
uword payload_size = insns.Size();
payload_size = Utils::RoundUp(payload_size, OS::PreferredCodeAlignment());
uword end = entry + payload_size;
ASSERT(Utils::IsAligned(beginning, sizeof(uint64_t)));
ASSERT(Utils::IsAligned(entry, sizeof(uint64_t)));
ASSERT(Utils::IsAligned(end, sizeof(uint64_t)));
for (uword* cursor = reinterpret_cast<uword*>(entry);
cursor < reinterpret_cast<uword*>(end); cursor++) {
WriteWordLiteralText(*cursor);
}
}
}
#if defined(TARGET_OS_LINUX)
assembly_stream_.Print(".section .rodata\n");
#elif defined(TARGET_OS_MACOS)
assembly_stream_.Print(".const\n");
#else
// Unsupported platform.
UNREACHABLE();
#endif
const char* data_symbol =
vm ? "_kDartVmSnapshotData" : "_kDartIsolateSnapshotData";
assembly_stream_.Print(".globl %s\n", data_symbol);
assembly_stream_.Print(".balign %" Pd ", 0\n",
OS::kMaxPreferredCodeAlignment);
assembly_stream_.Print("%s:\n", data_symbol);
uint8_t* buffer = clustered_stream->buffer();
intptr_t length = clustered_stream->bytes_written();
for (intptr_t i = 0; i < length; i++) {
assembly_stream_.Print(".byte %" Pd "\n", buffer[i]);
}
}
void BlobImageWriter::WriteText(WriteStream* clustered_stream, bool vm) {
// This header provides the gap to make the instructions snapshot look like a
// HeapPage.
intptr_t instructions_length = next_offset_;
instructions_blob_stream_.WriteWord(instructions_length);
intptr_t header_words = Image::kHeaderSize / sizeof(uword);
for (intptr_t i = 1; i < header_words; i++) {
instructions_blob_stream_.WriteWord(0);
}
for (intptr_t i = 0; i < instructions_.length(); i++) {
const Instructions& insns = *instructions_[i].insns_;
// 1. Write from the header to the entry point.
{
NoSafepointScope no_safepoint;
uword beginning = reinterpret_cast<uword>(insns.raw_ptr());
uword entry = beginning + Instructions::HeaderSize();
ASSERT(Utils::IsAligned(beginning, sizeof(uint64_t)));
ASSERT(Utils::IsAligned(entry, sizeof(uint64_t)));
// Write Instructions with the mark and VM heap bits set.
uword marked_tags = insns.raw_ptr()->tags_;
marked_tags = RawObject::VMHeapObjectTag::update(true, marked_tags);
marked_tags = RawObject::MarkBit::update(true, marked_tags);
instructions_blob_stream_.WriteWord(marked_tags);
beginning += sizeof(uword);
for (uword* cursor = reinterpret_cast<uword*>(beginning);
cursor < reinterpret_cast<uword*>(entry); cursor++) {
instructions_blob_stream_.WriteWord(*cursor);
}
}
// 2. Write from the entry point to the end.
{
NoSafepointScope no_safepoint;
uword beginning = reinterpret_cast<uword>(insns.raw()) - kHeapObjectTag;
uword entry = beginning + Instructions::HeaderSize();
uword payload_size = insns.Size();
payload_size = Utils::RoundUp(payload_size, OS::PreferredCodeAlignment());
uword end = entry + payload_size;
ASSERT(Utils::IsAligned(beginning, sizeof(uint64_t)));
ASSERT(Utils::IsAligned(entry, sizeof(uint64_t)));
ASSERT(Utils::IsAligned(end, sizeof(uint64_t)));
for (uword* cursor = reinterpret_cast<uword*>(entry);
cursor < reinterpret_cast<uword*>(end); cursor++) {
instructions_blob_stream_.WriteWord(*cursor);
}
}
}
}
RawInstructions* InstructionsReader::GetInstructionsAt(int32_t offset) {
ASSERT(Utils::IsAligned(offset, OS::PreferredCodeAlignment()));
RawInstructions* result = reinterpret_cast<RawInstructions*>(
reinterpret_cast<uword>(instructions_buffer_) + offset + kHeapObjectTag);
ASSERT(result->IsInstructions());
ASSERT(result->IsMarked());
return result;
}
RawObject* InstructionsReader::GetObjectAt(int32_t offset) {
ASSERT(Utils::IsAligned(offset, kWordSize));
RawObject* result = reinterpret_cast<RawObject*>(
reinterpret_cast<uword>(data_buffer_) + offset + kHeapObjectTag);
ASSERT(result->IsMarked());
return result;
}
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(IsObjectStoreClassId(class_id) || IsSingletonClassId(class_id));
return class_id;
}
#define READ_VM_SINGLETON_OBJ(id, obj) \
if (object_id == id) { \
return obj; \
}
RawObject* 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(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.
}
RawObject* SnapshotReader::ReadIndexedObject(intptr_t object_id,
intptr_t patch_object_id,
intptr_t patch_offset) {
intptr_t class_id = ClassIdFromObjectId(object_id);
if (IsObjectStoreClassId(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);
}
AddPatchRecord(object_id, patch_object_id, patch_offset);
return GetBackRef(object_id)->raw();
}
void SnapshotReader::AddPatchRecord(intptr_t object_id,
intptr_t patch_object_id,
intptr_t patch_offset) {
if (patch_object_id != kInvalidPatchIndex) {
ASSERT(object_id >= kMaxPredefinedObjectIds);
intptr_t index = (object_id - kMaxPredefinedObjectIds);
ASSERT(index >= max_vm_isolate_object_id_);
index -= max_vm_isolate_object_id_;
ASSERT(index < backward_references_->length());
BackRefNode& ref = (*backward_references_)[index];
ref.AddPatchRecord(patch_object_id, patch_offset);
}
}
void SnapshotReader::ProcessDeferredCanonicalizations() {
Type& typeobj = Type::Handle();
TypeArguments& typeargs = TypeArguments::Handle();
Object& newobj = Object::Handle();
for (intptr_t i = 0; i < backward_references_->length(); i++) {
BackRefNode& backref = (*backward_references_)[i];
if (backref.defer_canonicalization()) {
Object* objref = backref.reference();
// Object should either be a type or a type argument.
if (objref->IsType()) {
typeobj ^= objref->raw();
newobj = typeobj.Canonicalize();
} else {
ASSERT(objref->IsTypeArguments());
typeargs ^= objref->raw();
newobj = typeargs.Canonicalize();
}
if (newobj.raw() != objref->raw()) {
ZoneGrowableArray<intptr_t>* patches = backref.patch_records();
ASSERT(newobj.IsNull() || newobj.IsCanonical());
ASSERT(patches != NULL);
// First we replace the back ref table with the canonical object.
*objref = newobj.raw();
// Now we go over all the patch records and patch the canonical object.
for (intptr_t j = 0; j < patches->length(); j += 2) {
NoSafepointScope no_safepoint;
intptr_t patch_object_id = (*patches)[j];
intptr_t patch_offset = (*patches)[j + 1];
Object* target = GetBackRef(patch_object_id);
// We should not backpatch an object that is canonical.
if (!target->IsCanonical()) {
RawObject** rawptr =
reinterpret_cast<RawObject**>(target->raw()->ptr());
target->StorePointer((rawptr + patch_offset), newobj.raw());
}
}
} else {
ASSERT(objref->IsCanonical());
}
}
}
}
void SnapshotReader::ArrayReadFrom(intptr_t object_id,
const Array& result,
intptr_t len,
intptr_t tags) {
// Setup the object fields.
const intptr_t typeargs_offset =
GrowableObjectArray::type_arguments_offset() / kWordSize;
*TypeArgumentsHandle() ^=
ReadObjectImpl(kAsInlinedObject, object_id, typeargs_offset);
result.SetTypeArguments(*TypeArgumentsHandle());
bool as_reference = RawObject::IsCanonical(tags) ? false : true;
intptr_t offset = result.raw_ptr()->data() -
reinterpret_cast<RawObject**>(result.raw()->ptr());
for (intptr_t i = 0; i < len; i++) {
*PassiveObjectHandle() =
ReadObjectImpl(as_reference, object_id, (i + offset));
result.SetAt(i, *PassiveObjectHandle());
}
}
ScriptSnapshotReader::ScriptSnapshotReader(const uint8_t* buffer,
intptr_t size,
Thread* thread)
: SnapshotReader(buffer,
size,
Snapshot::kScript,
new ZoneGrowableArray<BackRefNode>(kNumInitialReferences),
thread) {}
ScriptSnapshotReader::~ScriptSnapshotReader() {
ResetBackwardReferenceTable();
}
MessageSnapshotReader::MessageSnapshotReader(const uint8_t* buffer,
intptr_t size,
Thread* thread)
: SnapshotReader(buffer,
size,
Snapshot::kMessage,
new ZoneGrowableArray<BackRefNode>(kNumInitialReferences),
thread) {}
MessageSnapshotReader::~MessageSnapshotReader() {
ResetBackwardReferenceTable();
}
SnapshotWriter::SnapshotWriter(Thread* thread,
Snapshot::Kind kind,
uint8_t** buffer,
ReAlloc alloc,
DeAlloc dealloc,
intptr_t initial_size,
ForwardList* forward_list,
bool can_send_any_object)
: BaseWriter(buffer, 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(RawObject* rawobj) {
WriteObjectImpl(rawobj, kAsInlinedObject);
WriteForwardedObjects();
}
uword SnapshotWriter::GetObjectTags(RawObject* raw) {
return raw->ptr()->tags_;
}
#define VM_OBJECT_CLASS_LIST(V) \
V(OneByteString) \
V(TwoByteString) \
V(Mint) \
V(Bigint) \
V(Double) \
V(ImmutableArray)
#define VM_OBJECT_WRITE(clazz) \
case clazz::kClassId: { \
object_id = forward_list_->AddObject(zone(), rawobj, kIsSerialized); \
Raw##clazz* raw_obj = reinterpret_cast<Raw##clazz*>(rawobj); \
raw_obj->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(RawObject* 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(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) {
RawClass* raw_class = reinterpret_cast<RawClass*>(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 {
switch (id) {
VM_OBJECT_CLASS_LIST(VM_OBJECT_WRITE)
case kTypedDataUint32ArrayCid: {
object_id = forward_list_->AddObject(zone(), rawobj, kIsSerialized);
RawTypedData* raw_obj = reinterpret_cast<RawTypedData*>(rawobj);
raw_obj->WriteTo(this, object_id, kind(), false);
return true;
}
default:
OS::Print("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
// An object visitor which will iterate over all the script objects in the heap
// and either count them or collect them into an array. This is used during
// full snapshot generation of the VM isolate to write out all script
// objects and their accompanying token streams.
class ScriptVisitor : public ObjectVisitor {
public:
explicit ScriptVisitor(Thread* thread)
: objHandle_(Object::Handle(thread->zone())), count_(0), scripts_(NULL) {}
ScriptVisitor(Thread* thread, const Array* scripts)
: objHandle_(Object::Handle(thread->zone())),
count_(0),
scripts_(scripts) {}
void VisitObject(RawObject* obj) {
if (obj->IsScript()) {
if (scripts_ != NULL) {
objHandle_ = obj;
scripts_->SetAt(count_, objHandle_);
}
count_ += 1;
}
}
intptr_t count() const { return count_; }
private:
Object& objHandle_;
intptr_t count_;
const Array* scripts_;
};
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);
}
ForwardList::~ForwardList() {
heap()->ResetObjectIdTable();
}
intptr_t ForwardList::AddObject(Zone* zone,
RawObject* 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);
heap()->SetObjectId(raw, object_id);
return object_id;
}
intptr_t ForwardList::FindObject(RawObject* raw) {
NoSafepointScope no_safepoint;
intptr_t id = heap()->GetObjectId(raw);
ASSERT(id == 0 || NodeForObjectId(id)->obj()->raw() == raw);
return (id == 0) ? static_cast<intptr_t>(kInvalidIndex) : id;
}
bool SnapshotWriter::CheckAndWritePredefinedObject(RawObject* 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>(reinterpret_cast<intptr_t>(rawobj));
return true;
}
intptr_t cid = rawobj->GetClassId();
if ((kind_ == Snapshot::kMessage) && (cid == kDoubleCid)) {
WriteVMIsolateObject(kDoubleObject);
RawDouble* rd = reinterpret_cast<RawDouble*>(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;
}
// Now check if it is an object from the VM isolate. These objects are shared
// by all isolates.
if (rawobj->IsVMHeapObject() && HandleVMIsolateObject(rawobj)) {
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) {
WriteVMIsolateObject(kNullObject);
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) {
RawClass* raw_class = reinterpret_cast<RawClass*>(rawobj);
intptr_t class_id = raw_class->ptr()->id_;
if (IsObjectStoreClassId(class_id)) {
intptr_t object_id = ObjectIdFromClassId(class_id);
WriteIndexedObject(object_id);
return true;
}
}
// Now check it is a preinitialized type object.
RawType* raw_type = reinterpret_cast<RawType*>(rawobj);
intptr_t index = GetTypeIndex(object_store(), raw_type);
if (index != kInvalidIndex) {
WriteIndexedObject(index);
return true;
}
return false;
}
void SnapshotWriter::WriteObjectImpl(RawObject* 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->IsCanonical();
intptr_t tags = raw->ptr()->tags_;
// 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(RawObject* raw,
intptr_t tags,
intptr_t object_id,
bool as_reference) {
NoSafepointScope no_safepoint;
RawClass* cls = class_table_->At(RawObject::ClassIdTag::decode(tags));
intptr_t class_id = cls->ptr()->id_;
ASSERT(class_id == RawObject::ClassIdTag::decode(tags));
if (class_id >= kNumPredefinedCids ||
RawObject::IsImplicitFieldClassId(class_id)) {
WriteInstance(raw, cls, tags, object_id, as_reference);
return;
}
switch (class_id) {
#define SNAPSHOT_WRITE(clazz) \
case clazz::kClassId: { \
Raw##clazz* raw_obj = reinterpret_cast<Raw##clazz*>(raw); \
raw_obj->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) {
RawTypedData* raw_obj = reinterpret_cast<RawTypedData*>(raw);
raw_obj->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) {
RawExternalTypedData* raw_obj =
reinterpret_cast<RawExternalTypedData*>(raw);
raw_obj->WriteTo(this, object_id, kind_, as_reference);
return;
}
#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(RawObject* obj) {
intptr_t object_id = writer_->forward_list_->FindObject(obj);
ASSERT(object_id != kInvalidIndex);
intptr_t tags = writer_->GetObjectTags(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.
RawObject* 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(RawClass* cls) {
ASSERT(!Snapshot::IsFull(kind_));
int class_id = cls->ptr()->id_;
ASSERT(!IsSingletonClassId(class_id) && !IsObjectStoreClassId(class_id));
// Write out the library url and class name.
RawLibrary* library = cls->ptr()->library_;
ASSERT(library != Library::null());
WriteObjectImpl(library->ptr()->url_, kAsInlinedObject);
WriteObjectImpl(cls->ptr()->name_, kAsInlinedObject);
}
void SnapshotWriter::WriteFunctionId(RawFunction* func, bool owner_is_class) {
ASSERT(kind_ == Snapshot::kScript);
RawClass* cls = (owner_is_class)
? reinterpret_cast<RawClass*>(func->ptr()->owner_)
: reinterpret_cast<RawPatchClass*>(func->ptr()->owner_)
->ptr()
->patched_class_;
// Write out the library url and class name.
RawLibrary* 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::WriteStaticImplicitClosure(intptr_t object_id,
RawFunction* 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.
RawClass* cls = GetFunctionOwner(func);
ASSERT(cls != Class::null());
RawLibrary* 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,
RawSmi* length,
RawTypeArguments* type_arguments,
RawObject* 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<RawObject*>(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<RawObject*>(length);
// Write out the type arguments.
WriteObjectImpl(type_arguments, kAsInlinedObject);
// Write out the individual object ids.
bool write_as_reference = RawObject::IsCanonical(tags) ? false : true;
for (intptr_t i = 0; i < len; i++) {
WriteObjectImpl(data[i], write_as_reference);
}
}
}
RawFunction* SnapshotWriter::IsSerializableClosure(RawClosure* closure) {
// Extract the function object to check if this closure
// can be sent in an isolate message.
RawFunction* 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();
}
RawClass* SnapshotWriter::GetFunctionOwner(RawFunction* func) {
RawObject* owner = func->ptr()->owner_;
uword tags = GetObjectTags(owner);
intptr_t class_id = RawObject::ClassIdTag::decode(tags);
if (class_id == kClassCid) {
return reinterpret_cast<RawClass*>(owner);
}
ASSERT(class_id == kPatchClassCid);
return reinterpret_cast<RawPatchClass*>(owner)->ptr()->patched_class_;
}
void SnapshotWriter::CheckForNativeFields(RawClass* 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(RawObject* raw,
RawClass* cls,
intptr_t tags,
intptr_t object_id,
bool as_reference) {
// Closure instances are handled by RawClosure::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 = cls->ptr()->next_field_offset_in_words_
<< 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);
// 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 = RawObject::IsCanonical(tags) ? false : true;
intptr_t offset = Instance::NextFieldOffset();
while (offset < next_field_offset) {
RawObject* raw_obj = *reinterpret_cast<RawObject**>(
reinterpret_cast<uword>(raw->ptr()) + offset);
WriteObjectImpl(raw_obj, write_as_reference);
offset += kWordSize;
}
}
return;
}
bool SnapshotWriter::AllowObjectsInDartLibrary(RawLibrary* library) {
return (library == object_store()->collection_library() ||
library == object_store()->core_library() ||
library == object_store()->typed_data_library());
}
intptr_t SnapshotWriter::FindVmSnapshotObject(RawObject* 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) {
thread()->clear_sticky_error();
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(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));
}
ScriptSnapshotWriter::ScriptSnapshotWriter(uint8_t** buffer, ReAlloc alloc)
: SnapshotWriter(Thread::Current(),
Snapshot::kScript,
buffer,
alloc,
NULL,
kInitialSize,
&forward_list_,
true /* can_send_any_object */),
forward_list_(thread(), kMaxPredefinedObjectIds) {
ASSERT(buffer != NULL);
ASSERT(alloc != NULL);
}
void ScriptSnapshotWriter::WriteScriptSnapshot(const Library& lib) {
ASSERT(kind() == Snapshot::kScript);
ASSERT(isolate() != NULL);
ASSERT(ClassFinalizer::AllClassesFinalized());
// Setup for long jump in case there is an exception while writing
// the snapshot.
LongJumpScope jump;
if (setjmp(*jump.Set()) == 0) {
// Reserve space in the output buffer for a snapshot header.
ReserveHeader();
// Write out the version string.
WriteVersionAndFeatures();
// Write out the library object.
{
NoSafepointScope no_safepoint;
// Write out the library object.
WriteObject(lib.raw());
FillHeader(kind());
}
} else {
ThrowException(exception_type(), exception_msg());
}
}
void SnapshotWriterVisitor::VisitPointers(RawObject** first, RawObject** last) {
for (RawObject** current = first; current <= last; current++) {
RawObject* raw_obj = *current;
writer_->WriteObjectImpl(raw_obj, as_references_);
}
}
MessageWriter::MessageWriter(uint8_t** buffer,
ReAlloc alloc,
DeAlloc dealloc,
bool can_send_any_object,
intptr_t* buffer_len)
: SnapshotWriter(Thread::Current(),
Snapshot::kMessage,
buffer,
alloc,
dealloc,
kInitialSize,
&forward_list_,
can_send_any_object),
forward_list_(thread(), kMaxPredefinedObjectIds),
buffer_len_(buffer_len) {
ASSERT(buffer != NULL);
ASSERT(alloc != NULL);
}
void MessageWriter::WriteMessage(const Object& obj) {
ASSERT(kind() == Snapshot::kMessage);
ASSERT(isolate() != NULL);
// Setup for long jump in case there is an exception while writing
// the message.
LongJumpScope jump;
if (setjmp(*jump.Set()) == 0) {
NoSafepointScope no_safepoint;
WriteObject(obj.raw());
if (buffer_len_ != NULL) {
*buffer_len_ = BytesWritten();
}
} else {
FreeBuffer();
ThrowException(exception_type(), exception_msg());
}
}
} // namespace dart