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dart / sdk.git / f860b70c98d03b454eb0ad2fba70e4e2c9641a6f / . / runtime / vm / class_finalizer.cc
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// Copyright (c) 2013, 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 <memory>
#include <utility>
#include "vm/class_finalizer.h"
#include "vm/canonical_tables.h"
#include "vm/compiler/jit/compiler.h"
#include "vm/flags.h"
#include "vm/hash_table.h"
#include "vm/heap/heap.h"
#include "vm/isolate.h"
#include "vm/kernel_loader.h"
#include "vm/log.h"
#include "vm/longjump.h"
#include "vm/object_store.h"
#include "vm/program_visitor.h"
#include "vm/runtime_entry.h"
#include "vm/symbols.h"
#include "vm/timeline.h"
#include "vm/type_testing_stubs.h"
namespace dart {
DEFINE_FLAG(bool, print_classes, false, "Prints details about loaded classes.");
DEFINE_FLAG(bool, trace_class_finalization, false, "Trace class finalization.");
DEFINE_FLAG(bool, trace_type_finalization, false, "Trace type finalization.");
bool ClassFinalizer::AllClassesFinalized() {
ObjectStore* object_store = IsolateGroup::Current()->object_store();
const GrowableObjectArray& classes =
GrowableObjectArray::Handle(object_store->pending_classes());
return classes.Length() == 0;
}
#if defined(DART_PRECOMPILED_RUNTIME)
bool ClassFinalizer::ProcessPendingClasses() {
ASSERT(AllClassesFinalized());
return true;
}
#else
// Removes optimized code once we load more classes, since CHA based
// optimizations may have become invalid.
// Only methods which owner classes where subclasses can be invalid.
// TODO(srdjan): Be even more precise by recording the exact CHA optimization.
static void RemoveCHAOptimizedCode(
const Class& subclass,
const GrowableArray<intptr_t>& added_subclass_to_cids) {
ASSERT(FLAG_use_cha_deopt);
if (added_subclass_to_cids.is_empty()) {
return;
}
// Switch all functions' code to unoptimized.
const ClassTable& class_table = *IsolateGroup::Current()->class_table();
Class& cls = Class::Handle();
for (intptr_t i = 0; i < added_subclass_to_cids.length(); i++) {
intptr_t cid = added_subclass_to_cids[i];
cls = class_table.At(cid);
ASSERT(!cls.IsNull());
cls.DisableCHAOptimizedCode(subclass);
}
}
static void AddSuperType(const AbstractType& type,
GrowableArray<intptr_t>* finalized_super_classes) {
ASSERT(type.HasTypeClass());
ASSERT(!type.IsDynamicType());
if (type.IsObjectType()) {
return;
}
const Class& cls = Class::Handle(type.type_class());
ASSERT(cls.is_finalized());
const intptr_t cid = cls.id();
for (intptr_t i = 0; i < finalized_super_classes->length(); i++) {
if ((*finalized_super_classes)[i] == cid) {
// Already added.
return;
}
}
finalized_super_classes->Add(cid);
const AbstractType& super_type = AbstractType::Handle(cls.super_type());
AddSuperType(super_type, finalized_super_classes);
}
// Use array instead of set since we expect very few subclassed classes
// to occur.
static void CollectFinalizedSuperClasses(
const Class& cls_,
GrowableArray<intptr_t>* finalized_super_classes) {
Class& cls = Class::Handle(cls_.ptr());
AbstractType& super_type = Type::Handle();
super_type = cls.super_type();
if (!super_type.IsNull()) {
if (super_type.HasTypeClass()) {
cls = super_type.type_class();
if (cls.is_finalized()) {
AddSuperType(super_type, finalized_super_classes);
}
}
}
}
class InterfaceFinder {
public:
InterfaceFinder(Zone* zone,
ClassTable* class_table,
GrowableArray<intptr_t>* cids)
: class_table_(class_table),
array_handles_(zone),
class_handles_(zone),
type_handles_(zone),
cids_(cids) {}
void FindAllInterfaces(const Class& klass) {
// The class is implementing its own interface.
cids_->Add(klass.id());
ScopedHandle<Array> array(&array_handles_);
ScopedHandle<Class> interface_class(&class_handles_);
ScopedHandle<Class> current_class(&class_handles_);
ScopedHandle<AbstractType> type(&type_handles_);
*current_class = klass.ptr();
while (true) {
// We don't care about top types.
const intptr_t cid = current_class->id();
if (cid == kObjectCid || cid == kDynamicCid || cid == kVoidCid) {
break;
}
// The class is implementing its directly declared implemented interfaces.
*array = klass.interfaces();
if (!array->IsNull()) {
for (intptr_t i = 0; i < array->Length(); ++i) {
*type ^= array->At(i);
*interface_class = class_table_->At(type->type_class_id());
FindAllInterfaces(*interface_class);
}
}
// The class is implementing its super type's interfaces.
*type = current_class->super_type();
if (type->IsNull()) break;
*current_class = class_table_->At(type->type_class_id());
}
}
private:
ClassTable* class_table_;
ReusableHandleStack<Array> array_handles_;
ReusableHandleStack<Class> class_handles_;
ReusableHandleStack<AbstractType> type_handles_;
GrowableArray<intptr_t>* cids_;
};
static void CollectImmediateSuperInterfaces(const Class& cls,
GrowableArray<intptr_t>* cids) {
const Array& interfaces = Array::Handle(cls.interfaces());
Class& ifc = Class::Handle();
AbstractType& type = AbstractType::Handle();
for (intptr_t i = 0; i < interfaces.Length(); ++i) {
type ^= interfaces.At(i);
if (!type.HasTypeClass()) continue;
ifc = type.type_class();
for (intptr_t j = 0; j < cids->length(); ++j) {
if ((*cids)[j] == ifc.id()) {
// Already added.
return;
}
}
cids->Add(ifc.id());
}
}
// Processing ObjectStore::pending_classes_ occurs:
// a) when bootstrap process completes (VerifyBootstrapClasses).
// b) after the user classes are loaded (dart_api).
bool ClassFinalizer::ProcessPendingClasses() {
Thread* thread = Thread::Current();
TIMELINE_DURATION(thread, Isolate, "ProcessPendingClasses");
auto isolate_group = thread->isolate_group();
ASSERT(isolate_group != nullptr);
HANDLESCOPE(thread);
ObjectStore* object_store = isolate_group->object_store();
const Error& error = Error::Handle(thread->zone(), thread->sticky_error());
if (!error.IsNull()) {
return false;
}
if (AllClassesFinalized()) {
return true;
}
LongJumpScope jump;
if (setjmp(*jump.Set()) == 0) {
GrowableObjectArray& class_array = GrowableObjectArray::Handle();
class_array = object_store->pending_classes();
ASSERT(!class_array.IsNull());
Class& cls = Class::Handle();
#if defined(DEBUG)
for (intptr_t i = 0; i < class_array.Length(); i++) {
cls ^= class_array.At(i);
ASSERT(cls.is_declaration_loaded());
}
#endif
// Finalize types in all classes.
for (intptr_t i = 0; i < class_array.Length(); i++) {
cls ^= class_array.At(i);
FinalizeTypesInClass(cls);
}
// Clear pending classes array.
class_array = GrowableObjectArray::New();
object_store->set_pending_classes(class_array);
VerifyImplicitFieldOffsets(); // Verification after an error may fail.
return true;
} else {
return false;
}
UNREACHABLE();
return true;
}
void ClassFinalizer::VerifyBootstrapClasses() {
if (FLAG_trace_class_finalization) {
OS::PrintErr("VerifyBootstrapClasses START.\n");
}
ObjectStore* object_store = IsolateGroup::Current()->object_store();
Class& cls = Class::Handle();
#if defined(DEBUG)
// Basic checking.
cls = object_store->object_class();
ASSERT(Instance::InstanceSize() == cls.host_instance_size());
cls = object_store->integer_implementation_class();
ASSERT(Integer::InstanceSize() == cls.host_instance_size());
cls = object_store->smi_class();
ASSERT(Smi::InstanceSize() == cls.host_instance_size());
cls = object_store->mint_class();
ASSERT(Mint::InstanceSize() == cls.host_instance_size());
cls = object_store->one_byte_string_class();
ASSERT(OneByteString::InstanceSize() == cls.host_instance_size());
cls = object_store->two_byte_string_class();
ASSERT(TwoByteString::InstanceSize() == cls.host_instance_size());
cls = object_store->external_one_byte_string_class();
ASSERT(ExternalOneByteString::InstanceSize() == cls.host_instance_size());
cls = object_store->external_two_byte_string_class();
ASSERT(ExternalTwoByteString::InstanceSize() == cls.host_instance_size());
cls = object_store->double_class();
ASSERT(Double::InstanceSize() == cls.host_instance_size());
cls = object_store->bool_class();
ASSERT(Bool::InstanceSize() == cls.host_instance_size());
cls = object_store->array_class();
ASSERT(Array::InstanceSize() == cls.host_instance_size());
cls = object_store->immutable_array_class();
ASSERT(ImmutableArray::InstanceSize() == cls.host_instance_size());
cls = object_store->weak_property_class();
ASSERT(WeakProperty::InstanceSize() == cls.host_instance_size());
cls = object_store->linked_hash_map_class();
ASSERT(LinkedHashMap::InstanceSize() == cls.host_instance_size());
#endif // defined(DEBUG)
// Remember the currently pending classes.
const GrowableObjectArray& class_array =
GrowableObjectArray::Handle(object_store->pending_classes());
for (intptr_t i = 0; i < class_array.Length(); i++) {
// TODO(iposva): Add real checks.
cls ^= class_array.At(i);
if (cls.is_finalized() || cls.is_prefinalized()) {
// Pre-finalized bootstrap classes must not define any fields.
ASSERT(!cls.HasInstanceFields());
}
}
// Finalize type hierarchy for types that aren't pre-finalized
// by Object::Init().
if (!ProcessPendingClasses()) {
// TODO(srdjan): Exit like a real VM instead.
const Error& err = Error::Handle(Thread::Current()->sticky_error());
OS::PrintErr("Could not verify bootstrap classes : %s\n",
err.ToErrorCString());
OS::Exit(255);
}
if (FLAG_trace_class_finalization) {
OS::PrintErr("VerifyBootstrapClasses END.\n");
}
IsolateGroup::Current()->heap()->Verify();
}
#endif // defined(DART_PRECOMPILED_RUNTIME)
void ClassFinalizer::FinalizeTypeParameters(Zone* zone,
const Class& cls,
const FunctionType& signature,
FinalizationKind finalization,
PendingTypes* pending_types) {
if (FLAG_trace_type_finalization) {
THR_Print(
"%s type parameters of %s '%s'\n",
finalization == kFinalize ? "Finalizing" : "Canonicalizing",
!cls.IsNull() ? "class" : "signature",
String::Handle(zone, !cls.IsNull() ? cls.Name() : signature.Name())
.ToCString());
}
const TypeParameters& type_params =
TypeParameters::Handle(zone, !cls.IsNull() ? cls.type_parameters()
: signature.type_parameters());
if (!type_params.IsNull()) {
TypeArguments& type_args = TypeArguments::Handle(zone);
type_args = type_params.bounds();
type_args =
FinalizeTypeArguments(zone, type_args, finalization, pending_types);
type_params.set_bounds(type_args);
type_args = type_params.defaults();
type_args =
FinalizeTypeArguments(zone, type_args, finalization, pending_types);
type_params.set_defaults(type_args);
type_params.OptimizeFlags();
}
}
// This function reports a compilation error if the recursive 'type' T being
// finalized is a non-contractive type, i.e. if the induced type set S of P is
// not finite, where P is the instantiation of T with its own type parameters.
// The induced type set S consists of the super types of any type in S as well
// as the type arguments of any parameterized type in S.
// The Dart Language Specification does not disallow the declaration and use of
// non-contractive types (this may change). They are nevertheless disallowed
// as an implementation restriction in the VM since they cause divergence.
// A non-contractive type can be detected by looking at the queue of types
// pending finalization that are mutually recursive with the checked type.
void ClassFinalizer::CheckRecursiveType(const AbstractType& type,
PendingTypes* pending_types) {
ASSERT(!type.IsFunctionType());
ASSERT(pending_types != NULL);
Zone* zone = Thread::Current()->zone();
if (FLAG_trace_type_finalization) {
THR_Print("Checking recursive type '%s': %s\n",
String::Handle(type.Name()).ToCString(), type.ToCString());
}
const Class& type_cls = Class::Handle(zone, type.type_class());
const TypeArguments& arguments =
TypeArguments::Handle(zone, type.arguments());
// A type can only be recursive via its type arguments.
ASSERT(!arguments.IsNull());
const intptr_t num_type_args = arguments.Length();
ASSERT(num_type_args > 0);
ASSERT(num_type_args == type_cls.NumTypeArguments());
const intptr_t num_type_params = type_cls.NumTypeParameters();
const intptr_t first_type_param = num_type_args - num_type_params;
// If the type is not generic (num_type_params == 0) or if its type parameters
// are instantiated, no divergence can occur. Note that if the type parameters
// are null, i.e. if the generic type is raw, they are considered
// instantiated and no divergence can occur.
if ((num_type_params == 0) ||
arguments.IsSubvectorInstantiated(first_type_param, num_type_params)) {
return;
}
// Consider mutually recursive and uninstantiated types pending finalization
// with the same type class and report an error if they are not equal in their
// raw form, i.e. where each class type parameter is substituted with dynamic.
// This test eliminates divergent types without restricting recursive types
// typically found in the wild.
TypeArguments& pending_arguments = TypeArguments::Handle(zone);
const intptr_t num_pending_types = pending_types->length();
for (intptr_t i = num_pending_types - 1; i >= 0; i--) {
const AbstractType& pending_type = pending_types->At(i);
if (FLAG_trace_type_finalization) {
THR_Print(" Comparing with pending type '%s': %s\n",
String::Handle(pending_type.Name()).ToCString(),
pending_type.ToCString());
}
if ((pending_type.ptr() != type.ptr()) && pending_type.IsType() &&
(pending_type.type_class() == type_cls.ptr())) {
pending_arguments = pending_type.arguments();
// By using TypeEquality::kInSubtypeTest, we throw a wider net than
// using canonical or syntactical equality and may reject more
// problematic declarations.
if (!pending_arguments.IsSubvectorEquivalent(
arguments, first_type_param, num_type_params,
TypeEquality::kInSubtypeTest) &&
!pending_arguments.IsSubvectorInstantiated(first_type_param,
num_type_params)) {
const TypeArguments& instantiated_arguments = TypeArguments::Handle(
zone, arguments.InstantiateFrom(Object::null_type_arguments(),
Object::null_type_arguments(),
kNoneFree, Heap::kNew));
const TypeArguments& instantiated_pending_arguments =
TypeArguments::Handle(zone, pending_arguments.InstantiateFrom(
Object::null_type_arguments(),
Object::null_type_arguments(),
kNoneFree, Heap::kNew));
// By using TypeEquality::kInSubtypeTest, we throw a wider net than
// using canonical or syntactical equality and may reject more
// problematic declarations.
if (!instantiated_pending_arguments.IsSubvectorEquivalent(
instantiated_arguments, first_type_param, num_type_params,
TypeEquality::kInSubtypeTest)) {
const String& type_name = String::Handle(zone, type.Name());
ReportError("illegal recursive type '%s'", type_name.ToCString());
}
}
}
}
}
// Expand the type arguments of the given type and finalize its full type
// argument vector. Return the number of type arguments (0 for a raw type).
intptr_t ClassFinalizer::ExpandAndFinalizeTypeArguments(
Zone* zone,
const AbstractType& type,
PendingTypes* pending_types) {
// The type class does not need to be finalized in order to finalize the type.
// Also, the type parameters of the type class must be finalized.
Class& type_class = Class::Handle(zone, type.type_class());
type_class.EnsureDeclarationLoaded();
// The finalized type argument vector needs num_type_arguments types.
const intptr_t num_type_arguments = type_class.NumTypeArguments();
// The class has num_type_parameters type parameters.
const intptr_t num_type_parameters = type_class.NumTypeParameters();
// Initialize the type argument vector.
// A null type argument vector indicates a raw type.
TypeArguments& arguments = TypeArguments::Handle(zone, type.arguments());
ASSERT(arguments.IsNull() || (arguments.Length() == num_type_parameters));
// The full type argument vector consists of the type arguments of the
// super types of type_class, which are initialized from the parsed
// type arguments, followed by the parsed type arguments.
TypeArguments& full_arguments = TypeArguments::Handle(zone);
if (num_type_arguments > 0) {
// If no type arguments were parsed and if the super types do not prepend
// type arguments to the vector, we can leave the vector as null.
if (!arguments.IsNull() || (num_type_arguments > num_type_parameters)) {
full_arguments = TypeArguments::New(num_type_arguments);
// Copy the parsed type arguments at the correct offset in the full type
// argument vector.
const intptr_t offset = num_type_arguments - num_type_parameters;
AbstractType& type_arg = AbstractType::Handle(zone, Type::DynamicType());
// Leave the temporary type arguments at indices [0..offset[ as null.
for (intptr_t i = 0; i < num_type_parameters; i++) {
// If no type parameters were provided, a raw type is desired, so we
// create a vector of dynamic.
if (!arguments.IsNull()) {
type_arg = arguments.TypeAt(i);
// The parsed type_arg may or may not be finalized.
if (type_arg.IsTypeRef()) {
// Dereferencing the TypeRef 'rotates' the cycle in the recursive
// type argument, so that the top level type arguments of the type
// do not start with a TypeRef, for better readability and possibly
// fewer later dereferences in various type traversal routines.
// This rotation is not required for correctness.
// The cycle containing TypeRefs always involves type arguments of
// the super class in the flatten argument vector, so it is safe to
// remove TypeRefs from type arguments corresponding to the type
// parameters of the type class.
// Such TypeRefs may appear after instantiation of types at runtime.
type_arg = TypeRef::Cast(type_arg).type();
}
}
full_arguments.SetTypeAt(offset + i, type_arg);
}
// Replace the compile-time argument vector (of length zero or
// num_type_parameters) of this type being finalized with the still
// unfinalized run-time argument vector (of length num_type_arguments).
// This type being finalized may be recursively reached via bounds
// checking or type arguments of its super type.
type.set_arguments(full_arguments);
// Finalize the current type arguments of the type, which are still the
// parsed type arguments.
if (!arguments.IsNull()) {
for (intptr_t i = 0; i < num_type_parameters; i++) {
type_arg = full_arguments.TypeAt(offset + i);
if (!type_arg.IsBeingFinalized()) {
type_arg = FinalizeType(type_arg, kFinalize, pending_types);
} else {
ASSERT(type_arg.IsTypeParameter());
// The bound of the type parameter is still being finalized.
}
full_arguments.SetTypeAt(offset + i, type_arg);
}
}
if (offset > 0) {
TrailPtr trail = new Trail(zone, 4);
FillAndFinalizeTypeArguments(zone, type_class, full_arguments, offset,
pending_types, trail);
}
if (full_arguments.IsRaw(0, num_type_arguments)) {
// The parameterized_type is raw. Set its argument vector to null, which
// is more efficient in type tests.
full_arguments = TypeArguments::null();
}
type.set_arguments(full_arguments);
} else {
ASSERT(full_arguments.IsNull()); // Use null vector for raw type.
}
}
ASSERT(full_arguments.IsNull() ||
!full_arguments.IsRaw(0, num_type_arguments));
return full_arguments.IsNull() ? 0 : full_arguments.Length();
}
// Finalize the type argument vector 'arguments' of the type defined by the
// class 'cls' parameterized with the type arguments 'cls_args'.
// The vector 'cls_args' is already initialized as a subvector at the correct
// position in the passed in 'arguments' vector.
// The subvector 'cls_args' has length cls.NumTypeParameters() and starts at
// offset cls.NumTypeArguments() - cls.NumTypeParameters() of the 'arguments'
// vector.
// The type argument vector of cls may overlap the type argument vector of its
// super class. In case of an overlap, the overlapped type arguments of the
// super class are already initialized. The still uninitialized ones have an
// offset smaller than 'num_uninitialized_arguments'.
// Example 1 (without overlap):
// Declared: class C<K, V> extends B<V> { ... }
// class B<T> extends A<int> { ... }
// Input: C<String, double> expressed as
// cls = C, arguments = [dynamic, dynamic, String, double],
// num_uninitialized_arguments = 2,
// i.e. cls_args = [String, double], offset = 2, length = 2.
// Output: arguments = [int, double, String, double]
// Example 2 (with overlap):
// Declared: class C<K, V> extends B<K> { ... }
// class B<T> extends A<int> { ... }
// Input: C<String, double> expressed as
// cls = C, arguments = [dynamic, String, double],
// num_uninitialized_arguments = 1,
// i.e. cls_args = [String, double], offset = 1, length = 2.
// Output: arguments = [int, String, double]
//
// It is too early to canonicalize the type arguments of the vector, because
// several type argument vectors may be mutually recursive and finalized at the
// same time. Canonicalization happens when pending types are processed.
// The trail is required to correctly instantiate a recursive type argument
// of the super type.
void ClassFinalizer::FillAndFinalizeTypeArguments(
Zone* zone,
const Class& cls,
const TypeArguments& arguments,
intptr_t num_uninitialized_arguments,
PendingTypes* pending_types,
TrailPtr trail) {
ASSERT(arguments.Length() >= cls.NumTypeArguments());
if (!cls.is_type_finalized()) {
#if defined(DART_PRECOMPILED_RUNTIME)
UNREACHABLE();
#else
FinalizeTypeParameters(zone, cls, Object::null_function_type(), kFinalize);
#endif // defined(DART_PRECOMPILED_RUNTIME)
}
AbstractType& super_type = AbstractType::Handle(zone, cls.super_type());
if (!super_type.IsNull()) {
const Class& super_class = Class::Handle(zone, super_type.type_class());
const intptr_t num_super_type_params = super_class.NumTypeParameters();
const intptr_t num_super_type_args = super_class.NumTypeArguments();
if (!super_type.IsFinalized() && !super_type.IsBeingFinalized()) {
super_type = FinalizeType(super_type, kFinalize, pending_types);
cls.set_super_type(super_type);
}
TypeArguments& super_type_args =
TypeArguments::Handle(zone, super_type.arguments());
// Offset of super type's type parameters in cls' type argument vector.
const intptr_t super_offset = num_super_type_args - num_super_type_params;
// If the super type is raw (i.e. super_type_args is null), set to dynamic.
AbstractType& super_type_arg =
AbstractType::Handle(zone, Type::DynamicType());
for (intptr_t i = super_offset; i < num_uninitialized_arguments; i++) {
if (!super_type_args.IsNull()) {
super_type_arg = super_type_args.TypeAt(i);
if (!super_type_arg.IsTypeRef()) {
if (super_type_arg.IsBeingFinalized()) {
// A type parameter being finalized indicates an unfinalized bound,
// but the bound is not relevant here. Its index is finalized.
if (!super_type_arg.IsTypeParameter()) {
if (super_type_arg.IsType()) {
CheckRecursiveType(super_type_arg, pending_types);
} else {
// The spec prohibits a typedef-declared function type to refer
// to itself. However, self-reference can occur via type
// arguments of the base class,
// e.g. `class Derived extends Base<TypeDef<Derived>> {}`.
ASSERT(super_type_arg.IsFunctionType());
}
if (FLAG_trace_type_finalization) {
THR_Print(
"Creating TypeRef '%s': '%s'\n",
String::Handle(zone, super_type_arg.Name()).ToCString(),
super_type_arg.ToCString());
}
super_type_arg = TypeRef::New(super_type_arg);
}
super_type_args.SetTypeAt(i, super_type_arg);
} else {
if (!super_type_arg.IsFinalized()) {
super_type_arg =
FinalizeType(super_type_arg, kFinalize, pending_types);
super_type_args.SetTypeAt(i, super_type_arg);
// Note that super_type_arg may still not be finalized here, in
// which case it is a TypeRef to a legal recursive type.
}
}
}
// Instantiate super_type_arg with the current argument vector.
if (!super_type_arg.IsInstantiated()) {
if (FLAG_trace_type_finalization && super_type_arg.IsTypeRef()) {
AbstractType& ref_type = AbstractType::Handle(
zone, TypeRef::Cast(super_type_arg).type());
THR_Print(
"Instantiating TypeRef '%s': '%s'\n"
" instantiator: '%s'\n",
String::Handle(zone, super_type_arg.Name()).ToCString(),
ref_type.ToCString(), arguments.ToCString());
}
// In the typical case of an F-bounded type, the instantiation of the
// super_type_arg from arguments is a fixpoint. Take the shortcut.
// Example: class B<T>; class D<T> extends B<D<T>>;
// While finalizing D<T>, the super type arg D<T> (a typeref) gets
// instantiated from vector [T], yielding itself.
if (super_type_arg.IsTypeRef() &&
(super_type_arg.arguments() == arguments.ptr())) {
ASSERT(super_type_arg.IsBeingFinalized());
arguments.SetTypeAt(i, super_type_arg);
continue;
}
super_type_arg = super_type_arg.InstantiateFrom(
arguments, Object::null_type_arguments(), kNoneFree, Heap::kOld,
trail);
if (super_type_arg.IsBeingFinalized() &&
!super_type_arg.IsTypeParameter()) {
// The super_type_arg was instantiated from a type being finalized.
// We need to finish finalizing its type arguments, unless it is a
// type parameter, in which case there is nothing more to do.
AbstractType& unfinalized_type = AbstractType::Handle(zone);
if (super_type_arg.IsTypeRef()) {
unfinalized_type = TypeRef::Cast(super_type_arg).type();
} else {
ASSERT(super_type_arg.IsType());
unfinalized_type = super_type_arg.ptr();
}
if (FLAG_trace_type_finalization) {
THR_Print(
"Instantiated unfinalized '%s': '%s'\n",
String::Handle(zone, unfinalized_type.Name()).ToCString(),
unfinalized_type.ToCString());
}
if (unfinalized_type.IsType()) {
CheckRecursiveType(unfinalized_type, pending_types);
pending_types->Add(unfinalized_type);
}
const Class& super_cls =
Class::Handle(zone, unfinalized_type.type_class());
const TypeArguments& super_args =
TypeArguments::Handle(zone, unfinalized_type.arguments());
// Mark as finalized before finalizing to avoid cycles.
unfinalized_type.SetIsFinalized();
// Although the instantiator is different between cls and super_cls,
// we still need to pass the current instantiation trail as to avoid
// divergence. Finalizing the type arguments of super_cls may indeed
// recursively require instantiating the same type_refs already
// present in the trail (see issue #29949).
FillAndFinalizeTypeArguments(
zone, super_cls, super_args,
super_cls.NumTypeArguments() - super_cls.NumTypeParameters(),
pending_types, trail);
if (FLAG_trace_type_finalization) {
THR_Print(
"Finalized instantiated '%s': '%s'\n",
String::Handle(zone, unfinalized_type.Name()).ToCString(),
unfinalized_type.ToCString());
}
}
}
}
arguments.SetTypeAt(i, super_type_arg);
}
FillAndFinalizeTypeArguments(zone, super_class, arguments, super_offset,
pending_types, trail);
}
}
TypeArgumentsPtr ClassFinalizer::FinalizeTypeArguments(
Zone* zone,
const TypeArguments& type_args,
FinalizationKind finalization,
PendingTypes* pending_types) {
if (type_args.IsNull()) return TypeArguments::null();
ASSERT(type_args.ptr() != Object::empty_type_arguments().ptr());
const intptr_t len = type_args.Length();
AbstractType& type = AbstractType::Handle(zone);
AbstractType& finalized_type = AbstractType::Handle(zone);
for (intptr_t i = 0; i < len; i++) {
type = type_args.TypeAt(i);
if (type.IsBeingFinalized()) {
ASSERT(finalization < kCanonicalize);
continue;
}
finalized_type = FinalizeType(type, kFinalize, pending_types);
if (type.ptr() != finalized_type.ptr()) {
type_args.SetTypeAt(i, finalized_type);
}
}
if (finalization >= kCanonicalize) {
return type_args.Canonicalize(Thread::Current(), nullptr);
}
return type_args.ptr();
}
AbstractTypePtr ClassFinalizer::FinalizeType(const AbstractType& type,
FinalizationKind finalization,
PendingTypes* pending_types) {
// Only the 'root' type of the graph can be canonicalized, after all depending
// types have been bound checked.
ASSERT((pending_types == NULL) || (finalization < kCanonicalize));
if (type.IsFinalized()) {
// Ensure type is canonical if canonicalization is requested.
if ((finalization >= kCanonicalize) && !type.IsCanonical() &&
!type.IsBeingFinalized()) {
return type.Canonicalize(Thread::Current(), nullptr);
}
return type.ptr();
}
Thread* thread = Thread::Current();
Zone* zone = thread->zone();
if (type.IsTypeRef()) {
if (type.IsBeingFinalized()) {
// The referenced type will be finalized later by the code that set the
// is_being_finalized mark bit.
return type.ptr();
}
AbstractType& ref_type =
AbstractType::Handle(zone, TypeRef::Cast(type).type());
ref_type = FinalizeType(ref_type, finalization, pending_types);
TypeRef::Cast(type).set_type(ref_type);
return type.ptr();
}
// Recursive types must be processed in FillAndFinalizeTypeArguments() and
// cannot be encountered here.
ASSERT(!type.IsBeingFinalized());
// Mark the type as being finalized in order to detect self reference.
type.SetIsBeingFinalized();
if (FLAG_trace_type_finalization) {
THR_Print("Finalizing type '%s'\n",
String::Handle(zone, type.Name()).ToCString());
}
if (type.IsTypeParameter()) {
const TypeParameter& type_parameter = TypeParameter::Cast(type);
const Class& parameterized_class =
Class::Handle(zone, type_parameter.parameterized_class());
// The base and index of a function type parameter are eagerly calculated
// upon loading and do not require adjustment here.
if (!parameterized_class.IsNull()) {
// The index must reflect the position of this type parameter in the type
// arguments vector of its parameterized class. The offset to add is the
// number of type arguments in the super type, which is equal to the
// difference in number of type arguments and type parameters of the
// parameterized class.
const intptr_t offset = parameterized_class.NumTypeArguments() -
parameterized_class.NumTypeParameters();
type_parameter.set_base(offset); // Informative, but not needed.
type_parameter.set_index(type_parameter.index() + offset);
// Remove the reference to the parameterized class.
type_parameter.set_parameterized_class_id(kClassCid);
}
type_parameter.SetIsFinalized();
AbstractType& upper_bound = AbstractType::Handle(zone);
upper_bound = type_parameter.bound();
if (!upper_bound.IsBeingFinalized()) {
upper_bound = FinalizeType(upper_bound, kFinalize);
type_parameter.set_bound(upper_bound);
}
if (FLAG_trace_type_finalization) {
THR_Print("Done finalizing type parameter at index %" Pd "\n",
type_parameter.index());
}
if (finalization >= kCanonicalize) {
return type_parameter.Canonicalize(thread, nullptr);
}
return type_parameter.ptr();
}
// If the type is a function type, we also need to finalize the types in its
// signature, i.e. finalize the result type and parameter types of the
// signature function of this function type.
if (type.IsFunctionType()) {
return FinalizeSignature(zone, FunctionType::Cast(type), finalization,
pending_types);
}
// This type is the root type of the type graph if no pending types queue is
// allocated yet. A function type is a collection of types, but not a root.
const bool is_root_type = pending_types == NULL;
if (is_root_type) {
pending_types = new PendingTypes(zone, 4);
}
// At this point, we can only have a Type.
ASSERT(type.IsType());
pending_types->Add(type);
const intptr_t num_expanded_type_arguments =
ExpandAndFinalizeTypeArguments(zone, type, pending_types);
// Self referencing types may get finalized indirectly.
if (!type.IsFinalized()) {
if (FLAG_trace_type_finalization) {
THR_Print("Marking type '%s' as finalized\n",
String::Handle(zone, type.Name()).ToCString());
}
// Mark the type as finalized.
type.SetIsFinalized();
}
if (FLAG_trace_type_finalization) {
THR_Print("Done finalizing type '%s' with %" Pd " type args: %s\n",
String::Handle(zone, type.Name()).ToCString(),
num_expanded_type_arguments, type.ToCString());
}
if (finalization >= kCanonicalize) {
if (FLAG_trace_type_finalization) {
THR_Print("Canonicalizing type '%s'\n",
String::Handle(zone, type.Name()).ToCString());
AbstractType& canonical_type =
AbstractType::Handle(zone, type.Canonicalize(thread, nullptr));
THR_Print("Done canonicalizing type '%s'\n",
String::Handle(zone, canonical_type.Name()).ToCString());
return canonical_type.ptr();
}
return type.Canonicalize(thread, nullptr);
} else {
return type.ptr();
}
}
AbstractTypePtr ClassFinalizer::FinalizeSignature(Zone* zone,
const FunctionType& signature,
FinalizationKind finalization,
PendingTypes* pending_types) {
// Finalize signature type parameter upper bounds and default args.
FinalizeTypeParameters(zone, Object::null_class(), signature, finalization,
pending_types);
AbstractType& type = AbstractType::Handle(zone);
AbstractType& finalized_type = AbstractType::Handle(zone);
// Finalize result type.
type = signature.result_type();
finalized_type = FinalizeType(type, kFinalize, pending_types);
if (finalized_type.ptr() != type.ptr()) {
signature.set_result_type(finalized_type);
}
// Finalize formal parameter types.
const intptr_t num_parameters = signature.NumParameters();
for (intptr_t i = 0; i < num_parameters; i++) {
type = signature.ParameterTypeAt(i);
finalized_type = FinalizeType(type, kFinalize, pending_types);
if (type.ptr() != finalized_type.ptr()) {
signature.SetParameterTypeAt(i, finalized_type);
}
}
if (FLAG_trace_type_finalization) {
THR_Print("Marking function type '%s' as finalized\n",
String::Handle(zone, signature.Name()).ToCString());
}
signature.SetIsFinalized();
if (finalization >= kCanonicalize) {
return signature.Canonicalize(Thread::Current(), nullptr);
}
return signature.ptr();
}
#if !defined(DART_PRECOMPILED_RUNTIME)
#if defined(TARGET_ARCH_X64)
static bool IsPotentialExactGeneric(const AbstractType& type) {
// TODO(dartbug.com/34170) Investigate supporting this for fields with types
// that depend on type parameters of the enclosing class.
if (type.IsType() && !type.IsDartFunctionType() && type.IsInstantiated() &&
!type.IsFutureOrType()) {
const Class& cls = Class::Handle(type.type_class());
return cls.IsGeneric();
}
return false;
}
#else
// TODO(dartbug.com/34170) Support other architectures.
static bool IsPotentialExactGeneric(const AbstractType& type) {
return false;
}
#endif
void ClassFinalizer::FinalizeMemberTypes(const Class& cls) {
// Note that getters and setters are explicitly listed as such in the list of
// functions of a class, so we do not need to consider fields as implicitly
// generating getters and setters.
// Most overriding conflicts are only static warnings, i.e. they are not
// reported as compile-time errors by the vm.
// Static warning examples are:
// - a static getter 'v' conflicting with an inherited instance setter 'v='.
// - a static setter 'v=' conflicting with an inherited instance member 'v'.
// - an instance member 'v' conflicting with an accessible static member 'v'
// or 'v=' of a super class (except that an instance method 'v' does not
// conflict with an accessible static setter 'v=' of a super class).
// The compile-time errors we report are:
// - a static member 'v' conflicting with an inherited instance member 'v'.
// - a static setter 'v=' conflicting with an inherited instance setter 'v='.
// - an instance method conflicting with an inherited instance field or
// instance getter.
// - an instance field or instance getter conflicting with an inherited
// instance method.
// Finalize type of fields and check for conflicts in super classes.
auto isolate_group = IsolateGroup::Current();
Zone* zone = Thread::Current()->zone();
Array& array = Array::Handle(zone, cls.fields());
Field& field = Field::Handle(zone);
AbstractType& type = AbstractType::Handle(zone);
Function& function = Function::Handle(zone);
FunctionType& signature = FunctionType::Handle(zone);
const intptr_t num_fields = array.Length();
const bool track_exactness = isolate_group->use_field_guards();
for (intptr_t i = 0; i < num_fields; i++) {
field ^= array.At(i);
type = field.type();
type = FinalizeType(type);
field.SetFieldType(type);
if (track_exactness && IsPotentialExactGeneric(type)) {
field.set_static_type_exactness_state(
StaticTypeExactnessState::Uninitialized());
}
function = field.InitializerFunction();
if (!function.IsNull()) {
// TODO(regis): It looks like the initializer is never set at this point.
// Remove this finalization code?
signature = function.signature();
signature ^= FinalizeType(signature);
function.set_signature(signature);
}
}
// Finalize function signatures and check for conflicts in super classes and
// interfaces.
array = cls.current_functions();
const intptr_t num_functions = array.Length();
for (intptr_t i = 0; i < num_functions; i++) {
function ^= array.At(i);
signature = function.signature();
signature ^= FinalizeType(signature);
function.set_signature(signature);
if (function.IsSetterFunction() || function.IsImplicitSetterFunction()) {
continue;
}
}
}
// For a class used as an interface marks this class and all its superclasses
// implemented.
//
// Does not mark its interfaces implemented because those would already be
// marked as such.
static void MarkImplemented(Zone* zone, const Class& iface) {
if (iface.is_implemented()) {
return;
}
Class& cls = Class::Handle(zone, iface.ptr());
AbstractType& type = AbstractType::Handle(zone);
while (!cls.is_implemented()) {
cls.set_is_implemented();
type = cls.super_type();
if (type.IsNull() || type.IsObjectType()) {
break;
}
cls = type.type_class();
}
}
#endif // !defined(DART_PRECOMPILED_RUNTIME)
void ClassFinalizer::FinalizeTypesInClass(const Class& cls) {
Thread* thread = Thread::Current();
HANDLESCOPE(thread);
cls.EnsureDeclarationLoaded();
if (cls.is_type_finalized()) {
return;
}
#if defined(DART_PRECOMPILED_RUNTIME)
UNREACHABLE();
#else
Zone* zone = thread->zone();
SafepointWriteRwLocker ml(thread, thread->isolate_group()->program_lock());
if (cls.is_type_finalized()) {
return;
}
if (FLAG_trace_class_finalization) {
THR_Print("Finalize types in %s\n", cls.ToCString());
}
// Finalize super class.
Class& super_class = Class::Handle(zone, cls.SuperClass());
if (!super_class.IsNull()) {
FinalizeTypesInClass(super_class);
}
// Finalize type parameters before finalizing the super type.
FinalizeTypeParameters(zone, cls, Object::null_function_type(),
kCanonicalize);
ASSERT(super_class.ptr() == cls.SuperClass()); // Not modified.
ASSERT(super_class.IsNull() || super_class.is_type_finalized());
// Finalize super type.
AbstractType& super_type = AbstractType::Handle(zone, cls.super_type());
if (!super_type.IsNull()) {
super_type = FinalizeType(super_type);
cls.set_super_type(super_type);
}
// Finalize interface types (but not necessarily interface classes).
Array& interface_types = Array::Handle(zone, cls.interfaces());
AbstractType& interface_type = AbstractType::Handle(zone);
for (intptr_t i = 0; i < interface_types.Length(); i++) {
interface_type ^= interface_types.At(i);
interface_type = FinalizeType(interface_type);
interface_types.SetAt(i, interface_type);
}
cls.set_is_type_finalized();
RegisterClassInHierarchy(thread->zone(), cls);
#endif // defined(DART_PRECOMPILED_RUNTIME)
}
#if !defined(DART_PRECOMPILED_RUNTIME)
void ClassFinalizer::RegisterClassInHierarchy(Zone* zone, const Class& cls) {
auto& type = AbstractType::Handle(zone, cls.super_type());
auto& other_cls = Class::Handle(zone);
// Add this class to the direct subclasses of the superclass, unless the
// superclass is Object.
if (!type.IsNull() && !type.IsObjectType()) {
other_cls = cls.SuperClass();
ASSERT(!other_cls.IsNull());
other_cls.AddDirectSubclass(cls);
}
// Add this class as an implementor to the implemented interface's type
// classes.
const auto& interfaces = Array::Handle(zone, cls.interfaces());
const intptr_t mixin_index =
cls.is_transformed_mixin_application() ? interfaces.Length() - 1 : -1;
for (intptr_t i = 0; i < interfaces.Length(); ++i) {
type ^= interfaces.At(i);
other_cls = type.type_class();
MarkImplemented(zone, other_cls);
other_cls.AddDirectImplementor(cls, /* is_mixin = */ i == mixin_index);
}
}
#endif // defined(DART_PRECOMPILED_RUNTIME)
void ClassFinalizer::FinalizeClass(const Class& cls) {
ASSERT(cls.is_type_finalized());
if (cls.is_finalized()) {
return;
}
#if defined(DART_PRECOMPILED_RUNTIME)
UNREACHABLE();
#else
Thread* thread = Thread::Current();
HANDLESCOPE(thread);
if (FLAG_trace_class_finalization) {
THR_Print("Finalize %s\n", cls.ToCString());
}
#if defined(SUPPORT_TIMELINE)
TimelineBeginEndScope tbes(thread, Timeline::GetCompilerStream(),
"FinalizeClass");
if (tbes.enabled()) {
tbes.SetNumArguments(1);
tbes.CopyArgument(0, "class", cls.ToCString());
}
#endif // defined(SUPPORT_TIMELINE)
// If loading from a kernel, make sure that the class is fully loaded.
ASSERT(cls.IsTopLevel() || (cls.kernel_offset() > 0));
if (!cls.is_loaded()) {
kernel::KernelLoader::FinishLoading(cls);
if (cls.is_finalized()) {
return;
}
}
// Ensure super class is finalized.
const Class& super = Class::Handle(cls.SuperClass());
if (!super.IsNull()) {
FinalizeClass(super);
if (cls.is_finalized()) {
return;
}
}
// Mark as loaded and finalized.
cls.Finalize();
if (FLAG_print_classes) {
PrintClassInformation(cls);
}
FinalizeMemberTypes(cls);
if (cls.is_enum_class()) {
AllocateEnumValues(cls);
}
// The rest of finalization for non-top-level class has to be done with
// stopped mutators. It will be done by AllocateFinalizeClass. before new
// instance of a class is created in GetAllocationStubForClass.
if (cls.IsTopLevel()) {
cls.set_is_allocate_finalized();
}
#endif // defined(DART_PRECOMPILED_RUNTIME)
}
#if !defined(DART_PRECOMPILED_RUNTIME)
ErrorPtr ClassFinalizer::AllocateFinalizeClass(const Class& cls) {
ASSERT(IsolateGroup::Current()->program_lock()->IsCurrentThreadWriter());
ASSERT(cls.is_finalized());
ASSERT(!cls.is_allocate_finalized());
Thread* thread = Thread::Current();
HANDLESCOPE(thread);
if (FLAG_trace_class_finalization) {
THR_Print("Allocate finalize %s\n", cls.ToCString());
}
#if defined(SUPPORT_TIMELINE)
TimelineBeginEndScope tbes(thread, Timeline::GetCompilerStream(),
"AllocateFinalizeClass");
if (tbes.enabled()) {
tbes.SetNumArguments(1);
tbes.CopyArgument(0, "class", cls.ToCString());
}
#endif // defined(SUPPORT_TIMELINE)
// Run additional checks after all types are finalized.
if (FLAG_use_cha_deopt && !cls.IsTopLevel()) {
{
GrowableArray<intptr_t> cids;
CollectFinalizedSuperClasses(cls, &cids);
CollectImmediateSuperInterfaces(cls, &cids);
RemoveCHAOptimizedCode(cls, cids);
}
Zone* zone = thread->zone();
ClassTable* class_table = thread->isolate_group()->class_table();
auto& interface_class = Class::Handle(zone);
// We scan every interface this [cls] implements and invalidate all CHA
// code which depends on knowing the implementors of that interface.
{
GrowableArray<intptr_t> cids;
InterfaceFinder finder(zone, class_table, &cids);
finder.FindAllInterfaces(cls);
for (intptr_t j = 0; j < cids.length(); ++j) {
interface_class = class_table->At(cids[j]);
interface_class.DisableCHAImplementorUsers();
}
}
}
cls.set_is_allocate_finalized();
return Error::null();
}
ErrorPtr ClassFinalizer::LoadClassMembers(const Class& cls) {
ASSERT(IsolateGroup::Current()->program_lock()->IsCurrentThreadWriter());
ASSERT(!cls.is_finalized());
LongJumpScope jump;
if (setjmp(*jump.Set()) == 0) {
#if !defined(DART_PRECOMPILED_RUNTIME)
cls.EnsureDeclarationLoaded();
#endif
ASSERT(cls.is_type_finalized());
ClassFinalizer::FinalizeClass(cls);
return Error::null();
} else {
return Thread::Current()->StealStickyError();
}
}
// Allocate instances for each enumeration value, and populate the
// static field 'values'.
// By allocating the instances programmatically, we save an implicit final
// getter function object for each enumeration value and for the
// values field. We also don't have to generate the code for these getters
// from thin air (no source code is available).
void ClassFinalizer::AllocateEnumValues(const Class& enum_cls) {
Thread* thread = Thread::Current();
Zone* zone = thread->zone();
const Field& index_field =
Field::Handle(zone, enum_cls.LookupInstanceField(Symbols::Index()));
ASSERT(!index_field.IsNull());
const Field& name_field = Field::Handle(
zone, enum_cls.LookupInstanceFieldAllowPrivate(Symbols::_name()));
ASSERT(!name_field.IsNull());
const String& enum_name = String::Handle(zone, enum_cls.ScrubbedName());
const Array& fields = Array::Handle(zone, enum_cls.fields());
Field& field = Field::Handle(zone);
Instance& enum_value = Instance::Handle(zone);
String& enum_ident = String::Handle(zone);
enum_ident =
Symbols::FromConcat(thread, Symbols::_DeletedEnumPrefix(), enum_name);
enum_value = Instance::New(enum_cls, Heap::kOld);
enum_value.SetField(index_field, Smi::Handle(zone, Smi::New(-1)));
enum_value.SetField(name_field, enum_ident);
enum_value = enum_value.Canonicalize(thread);
ASSERT(!enum_value.IsNull());
ASSERT(enum_value.IsCanonical());
const Field& sentinel = Field::Handle(
zone, enum_cls.LookupStaticField(Symbols::_DeletedEnumSentinel()));
ASSERT(!sentinel.IsNull());
// The static const field contains `Object::null()` instead of
// `Object::sentinel()` - so it's not considered an initializing store.
sentinel.SetStaticConstFieldValue(enum_value,
/*assert_initializing_store*/ false);
ASSERT(enum_cls.kernel_offset() > 0);
Object& error = Error::Handle(zone);
for (intptr_t i = 0; i < fields.Length(); i++) {
field = Field::RawCast(fields.At(i));
if (!field.is_static() || !field.is_const() ||
(sentinel.ptr() == field.ptr())) {
continue;
}
// Hot-reload expects the static const fields to be evaluated when
// performing a reload.
if (!FLAG_precompiled_mode) {
error = field.StaticConstFieldValue();
if (error.IsError()) {
ReportError(Error::Cast(error));
}
}
}
}
void ClassFinalizer::PrintClassInformation(const Class& cls) {
Thread* thread = Thread::Current();
HANDLESCOPE(thread);
const String& class_name = String::Handle(cls.Name());
THR_Print("class '%s'", class_name.ToCString());
const Library& library = Library::Handle(cls.library());
if (!library.IsNull()) {
THR_Print(" library '%s%s':\n", String::Handle(library.url()).ToCString(),
String::Handle(library.private_key()).ToCString());
} else {
THR_Print(" (null library):\n");
}
const AbstractType& super_type = AbstractType::Handle(cls.super_type());
if (super_type.IsNull()) {
THR_Print(" Super: NULL");
} else {
const String& super_name = String::Handle(super_type.Name());
THR_Print(" Super: %s", super_name.ToCString());
}
const Array& interfaces_array = Array::Handle(cls.interfaces());
if (interfaces_array.Length() > 0) {
THR_Print("; interfaces: ");
AbstractType& interface = AbstractType::Handle();
intptr_t len = interfaces_array.Length();
for (intptr_t i = 0; i < len; i++) {
interface ^= interfaces_array.At(i);
THR_Print(" %s ", interface.ToCString());
}
}
THR_Print("\n");
const Array& functions_array = Array::Handle(cls.current_functions());
Function& function = Function::Handle();
intptr_t len = functions_array.Length();
for (intptr_t i = 0; i < len; i++) {
function ^= functions_array.At(i);
THR_Print(" %s\n", function.ToCString());
}
const Array& fields_array = Array::Handle(cls.fields());
Field& field = Field::Handle();
len = fields_array.Length();
for (intptr_t i = 0; i < len; i++) {
field ^= fields_array.At(i);
THR_Print(" %s\n", field.ToCString());
}
}
#endif // !defined(DART_PRECOMPILED_RUNTIME)
void ClassFinalizer::ReportError(const Error& error) {
Report::LongJump(error);
UNREACHABLE();
}
void ClassFinalizer::ReportError(const char* format, ...) {
va_list args;
va_start(args, format);
const Script& null_script = Script::Handle();
Report::MessageV(Report::kError, null_script, TokenPosition::kNoSource,
Report::AtLocation, format, args);
va_end(args);
UNREACHABLE();
}
#if !defined(DART_PRECOMPILED_RUNTIME)
void ClassFinalizer::VerifyImplicitFieldOffsets() {
#ifdef DEBUG
Thread* thread = Thread::Current();
auto isolate_group = thread->isolate_group();
if (isolate_group->obfuscate()) {
// Field names are obfuscated.
return;
}
Zone* zone = thread->zone();
const ClassTable& class_table = *(isolate_group->class_table());
Class& cls = Class::Handle(zone);
Array& fields_array = Array::Handle(zone);
Field& field = Field::Handle(zone);
String& name = String::Handle(zone);
String& expected_name = String::Handle(zone);
Error& error = Error::Handle(zone);
TypeParameter& type_param = TypeParameter::Handle(zone);
// Now verify field offsets of '_ByteBuffer' class.
cls = class_table.At(kByteBufferCid);
error = cls.EnsureIsFinalized(thread);
ASSERT(error.IsNull());
fields_array ^= cls.fields();
ASSERT(fields_array.Length() == ByteBuffer::NumberOfFields());
field ^= fields_array.At(0);
ASSERT(field.HostOffset() == ByteBuffer::data_offset());
name ^= field.name();
expected_name ^= String::New("_data");
ASSERT(String::EqualsIgnoringPrivateKey(name, expected_name));
// Now verify field offsets of 'Pointer' class.
cls = class_table.At(kFfiPointerCid);
error = cls.EnsureIsFinalized(thread);
ASSERT(error.IsNull());
ASSERT(cls.NumTypeParameters() == 1);
type_param = cls.TypeParameterAt(0);
ASSERT(Pointer::kNativeTypeArgPos == type_param.index());
#endif
}
void ClassFinalizer::SortClasses() {
auto T = Thread::Current();
auto Z = T->zone();
auto IG = T->isolate_group();
// Prevent background compiler from adding deferred classes or canonicalizing
// new types while classes are being sorted and type hashes are modified.
NoBackgroundCompilerScope no_bg_compiler(T);
SafepointWriteRwLocker ml(T, T->isolate_group()->program_lock());
ClassTable* table = IG->class_table();
intptr_t num_cids = table->NumCids();
std::unique_ptr<intptr_t[]> old_to_new_cid(new intptr_t[num_cids]);
for (intptr_t cid = 0; cid < kNumPredefinedCids; cid++) {
old_to_new_cid[cid] = cid; // The predefined classes cannot change cids.
}
for (intptr_t cid = kNumPredefinedCids; cid < num_cids; cid++) {
old_to_new_cid[cid] = -1;
}
intptr_t next_new_cid = kNumPredefinedCids;
GrowableArray<intptr_t> dfs_stack;
Class& cls = Class::Handle(Z);
GrowableObjectArray& subclasses = GrowableObjectArray::Handle(Z);
// Object doesn't use its subclasses list.
for (intptr_t cid = kNumPredefinedCids; cid < num_cids; cid++) {
if (!table->HasValidClassAt(cid)) {
continue;
}
cls = table->At(cid);
if (!cls.is_declaration_loaded()) {
continue;
}
if (cls.SuperClass() == IG->object_store()->object_class()) {
dfs_stack.Add(cid);
}
}
while (dfs_stack.length() > 0) {
intptr_t cid = dfs_stack.RemoveLast();
ASSERT(table->HasValidClassAt(cid));
cls = table->At(cid);
ASSERT(!cls.IsNull());
if (old_to_new_cid[cid] == -1) {
old_to_new_cid[cid] = next_new_cid++;
if (FLAG_trace_class_finalization) {
THR_Print("%" Pd ": %s, was %" Pd "\n", old_to_new_cid[cid],
cls.ToCString(), cid);
}
}
subclasses = cls.direct_subclasses();
if (!subclasses.IsNull()) {
for (intptr_t i = 0; i < subclasses.Length(); i++) {
cls ^= subclasses.At(i);
ASSERT(!cls.IsNull());
dfs_stack.Add(cls.id());
}
}
}
// Top-level classes, typedefs, patch classes, etc.
for (intptr_t cid = kNumPredefinedCids; cid < num_cids; cid++) {
if (old_to_new_cid[cid] == -1) {
old_to_new_cid[cid] = next_new_cid++;
if (FLAG_trace_class_finalization && table->HasValidClassAt(cid)) {
cls = table->At(cid);
THR_Print("%" Pd ": %s, was %" Pd "\n", old_to_new_cid[cid],
cls.ToCString(), cid);
}
}
}
ASSERT(next_new_cid == num_cids);
RemapClassIds(old_to_new_cid.get());
RehashTypes(); // Types use cid's as part of their hashes.
IG->RehashConstants(); // Const objects use cid's as part of their hashes.
// Ensure any newly spawned isolate will apply this permutation map right
// after kernel loading.
IG->source()->cid_permutation_map = std::move(old_to_new_cid);
}
class CidRewriteVisitor : public ObjectVisitor {
public:
explicit CidRewriteVisitor(intptr_t* old_to_new_cids)
: old_to_new_cids_(old_to_new_cids) {}
intptr_t Map(intptr_t cid) {
ASSERT(cid != -1);
return old_to_new_cids_[cid];
}
void VisitObject(ObjectPtr obj) {
if (obj->IsClass()) {
ClassPtr cls = Class::RawCast(obj);
const classid_t old_cid = cls->untag()->id_;
if (ClassTable::IsTopLevelCid(old_cid)) {
// We don't remap cids of top level classes.
return;
}
cls->untag()->id_ = Map(old_cid);
} else if (obj->IsField()) {
FieldPtr field = Field::RawCast(obj);
field->untag()->guarded_cid_ = Map(field->untag()->guarded_cid_);
field->untag()->is_nullable_ = Map(field->untag()->is_nullable_);
} else if (obj->IsTypeParameter()) {
TypeParameterPtr param = TypeParameter::RawCast(obj);
param->untag()->parameterized_class_id_ =
Map(param->untag()->parameterized_class_id_);
} else if (obj->IsType()) {
TypePtr type = Type::RawCast(obj);
ObjectPtr id = type->untag()->type_class_id();
if (!id->IsHeapObject()) {
type->untag()->set_type_class_id(
Smi::New(Map(Smi::Value(Smi::RawCast(id)))));
}
} else {
intptr_t old_cid = obj->GetClassId();
intptr_t new_cid = Map(old_cid);
if (old_cid != new_cid) {
// Don't touch objects that are unchanged. In particular, Instructions,
// which are write-protected.
obj->untag()->SetClassIdUnsynchronized(new_cid);
}
}
}
private:
intptr_t* old_to_new_cids_;
};
void ClassFinalizer::RemapClassIds(intptr_t* old_to_new_cid) {
Thread* T = Thread::Current();
IsolateGroup* IG = T->isolate_group();
// Code, ICData, allocation stubs have now-invalid cids.
ClearAllCode();
{
// The [HeapIterationScope] also safepoints all threads.
HeapIterationScope his(T);
IG->shared_class_table()->Remap(old_to_new_cid);
IG->set_remapping_cids(true);
// Update the class table. Do it before rewriting cids in headers, as
// the heap walkers load an object's size *after* calling the visitor.
IG->class_table()->Remap(old_to_new_cid);
// Rewrite cids in headers and cids in Classes, Fields, Types and
// TypeParameters.
{
CidRewriteVisitor visitor(old_to_new_cid);
IG->heap()->VisitObjects(&visitor);
}
IG->set_remapping_cids(false);
#if defined(DEBUG)
IG->class_table()->Validate();
#endif
}
#if defined(DEBUG)
IG->heap()->Verify();
#endif
}
// Clears the cached canonicalized hash codes for all instances which directly
// (or indirectly) depend on class ids.
//
// In the Dart VM heap the following instances directly use cids for the
// computation of canonical hash codes:
//
// * TypePtr (due to UntaggedType::type_class_id_)
// * TypeParameterPtr (due to UntaggedTypeParameter::parameterized_class_id_)
//
// The following instances use cids for the computation of canonical hash codes
// indirectly:
//
// * TypeRefPtr (due to UntaggedTypeRef::type_->type_class_id)
// * TypePtr (due to type arguments)
// * FunctionTypePtr (due to the result and parameter types)
// * TypeArgumentsPtr (due to type references)
// * InstancePtr (due to instance fields)
// * ArrayPtr (due to type arguments & array entries)
//
// Caching of the canonical hash codes happens for:
//
// * UntaggedType::hash_
// * UntaggedFunctionType::hash_
// * UntaggedTypeParameter::hash_
// * UntaggedTypeArguments::hash_
// * InstancePtr (weak table)
// * ArrayPtr (weak table)
//
// No caching of canonical hash codes (i.e. it gets re-computed every time)
// happens for:
//
// * TypeRefPtr (computed via UntaggedTypeRef::type_->type_class_id)
//
// Usages of canonical hash codes are:
//
// * ObjectStore::canonical_types()
// * ObjectStore::canonical_function_types()
// * ObjectStore::canonical_type_parameters()
// * ObjectStore::canonical_type_arguments()
// * Class::constants()
//
class ClearTypeHashVisitor : public ObjectVisitor {
public:
explicit ClearTypeHashVisitor(Zone* zone)
: type_param_(TypeParameter::Handle(zone)),
type_(Type::Handle(zone)),
function_type_(FunctionType::Handle(zone)),
type_args_(TypeArguments::Handle(zone)) {}
void VisitObject(ObjectPtr obj) {
if (obj->IsTypeParameter()) {
type_param_ ^= obj;
type_param_.SetHash(0);
} else if (obj->IsType()) {
type_ ^= obj;
type_.SetHash(0);
} else if (obj->IsFunctionType()) {
function_type_ ^= obj;
function_type_.SetHash(0);
} else if (obj->IsTypeArguments()) {
type_args_ ^= obj;
type_args_.SetHash(0);
}
}
private:
TypeParameter& type_param_;
Type& type_;
FunctionType& function_type_;
TypeArguments& type_args_;
};
void ClassFinalizer::RehashTypes() {
auto T = Thread::Current();
auto Z = T->zone();
auto IG = T->isolate_group();
// Clear all cached hash values.
{
HeapIterationScope his(T);
ClearTypeHashVisitor visitor(Z);
IG->heap()->VisitObjects(&visitor);
}
// Rehash the canonical Types table.
ObjectStore* object_store = IG->object_store();
Array& types = Array::Handle(Z);
Type& type = Type::Handle(Z);
{
CanonicalTypeSet types_table(Z, object_store->canonical_types());
types = HashTables::ToArray(types_table, false);
types_table.Release();
}
intptr_t dict_size = Utils::RoundUpToPowerOfTwo(types.Length() * 4 / 3);
CanonicalTypeSet types_table(
Z, HashTables::New<CanonicalTypeSet>(dict_size, Heap::kOld));
for (intptr_t i = 0; i < types.Length(); i++) {
type ^= types.At(i);
bool present = types_table.Insert(type);
// Two recursive types with different topology (and hashes) may be equal.
ASSERT(!present || type.IsRecursive());
}
object_store->set_canonical_types(types_table.Release());
// Rehash the canonical FunctionTypes table.
Array& function_types = Array::Handle(Z);
FunctionType& function_type = FunctionType::Handle(Z);
{
CanonicalFunctionTypeSet function_types_table(
Z, object_store->canonical_function_types());
function_types = HashTables::ToArray(function_types_table, false);
function_types_table.Release();
}
dict_size = Utils::RoundUpToPowerOfTwo(function_types.Length() * 4 / 3);
CanonicalFunctionTypeSet function_types_table(
Z, HashTables::New<CanonicalFunctionTypeSet>(dict_size, Heap::kOld));
for (intptr_t i = 0; i < function_types.Length(); i++) {
function_type ^= function_types.At(i);
bool present = function_types_table.Insert(function_type);
// Two recursive types with different topology (and hashes) may be equal.
ASSERT(!present || function_type.IsRecursive());
}
object_store->set_canonical_function_types(function_types_table.Release());
// Rehash the canonical TypeParameters table.
Array& typeparams = Array::Handle(Z);
TypeParameter& typeparam = TypeParameter::Handle(Z);
{
CanonicalTypeParameterSet typeparams_table(
Z, object_store->canonical_type_parameters());
typeparams = HashTables::ToArray(typeparams_table, false);
typeparams_table.Release();
}
dict_size = Utils::RoundUpToPowerOfTwo(typeparams.Length() * 4 / 3);
CanonicalTypeParameterSet typeparams_table(
Z, HashTables::New<CanonicalTypeParameterSet>(dict_size, Heap::kOld));
for (intptr_t i = 0; i < typeparams.Length(); i++) {
typeparam ^= typeparams.At(i);
bool present = typeparams_table.Insert(typeparam);
// Two recursive types with different topology (and hashes) may be equal.
ASSERT(!present || typeparam.IsRecursive());
}
object_store->set_canonical_type_parameters(typeparams_table.Release());
// Rehash the canonical TypeArguments table.
Array& typeargs = Array::Handle(Z);
TypeArguments& typearg = TypeArguments::Handle(Z);
{
CanonicalTypeArgumentsSet typeargs_table(
Z, object_store->canonical_type_arguments());
typeargs = HashTables::ToArray(typeargs_table, false);
typeargs_table.Release();
}
// The canonical constant tables use canonical hashcodes which can change
// due to cid-renumbering.
IG->RehashConstants();
dict_size = Utils::RoundUpToPowerOfTwo(typeargs.Length() * 4 / 3);
CanonicalTypeArgumentsSet typeargs_table(
Z, HashTables::New<CanonicalTypeArgumentsSet>(dict_size, Heap::kOld));
for (intptr_t i = 0; i < typeargs.Length(); i++) {
typearg ^= typeargs.At(i);
bool present = typeargs_table.Insert(typearg);
// Two recursive types with different topology (and hashes) may be equal.
ASSERT(!present || typearg.IsRecursive());
}
object_store->set_canonical_type_arguments(typeargs_table.Release());
}
void ClassFinalizer::ClearAllCode(bool including_nonchanging_cids) {
auto const thread = Thread::Current();
auto const isolate_group = thread->isolate_group();
SafepointWriteRwLocker ml(thread, isolate_group->program_lock());
StackZone stack_zone(thread);
HANDLESCOPE(thread);
auto const zone = thread->zone();
class ClearCodeVisitor : public FunctionVisitor {
public:
ClearCodeVisitor(Zone* zone, bool force)
: force_(force),
pool_(ObjectPool::Handle(zone)),
entry_(Object::Handle(zone)) {}
void VisitClass(const Class& cls) {
if (force_ || cls.id() >= kNumPredefinedCids) {
cls.DisableAllocationStub();
}
}
void VisitFunction(const Function& function) {
function.ClearCode();
function.ClearICDataArray();
}
private:
const bool force_;
ObjectPool& pool_;
Object& entry_;
};
ClearCodeVisitor visitor(zone, including_nonchanging_cids);
ProgramVisitor::WalkProgram(zone, isolate_group, &visitor);
// Apart from normal function code and allocation stubs we have two global
// code objects to clear.
if (including_nonchanging_cids) {
auto object_store = isolate_group->object_store();
auto& null_code = Code::Handle(zone);
object_store->set_build_method_extractor_code(null_code);
}
}
#endif // !defined(DART_PRECOMPILED_RUNTIME)
} // namespace dart