Files
sdk/runtime/lib/function.cc
T
Alexander Markov 9b67ccf7d8 [vm] Handle equal but not identical type args when comparing instantiated tear-offs
It is possible to instantiate a tear-off of generic function with type
arguments which are equivalent (equal) but not identical, for example
[int] and [int*]. So, operator== on closures changed to compare
delayed type arguments of implicit closures for equality.

Fixes https://github.com/dart-lang/sdk/issues/46836
TEST=language/closure/identity_equality_tearoff_test (in weak mode)

Change-Id: I610eb226a7a244deb6415f8d92f74e941371bb50
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/209266
Reviewed-by: Tess Strickland <sstrickl@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
2021-08-07 20:49:27 +00:00

99 lines
3.6 KiB
C++

// 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/bootstrap_natives.h"
#include "vm/compiler/jit/compiler.h"
#include "vm/dart_entry.h"
#include "vm/exceptions.h"
#include "vm/native_entry.h"
#include "vm/object.h"
#include "vm/symbols.h"
namespace dart {
DEFINE_NATIVE_ENTRY(Function_apply, 0, 2) {
const int kTypeArgsLen = 0; // TODO(regis): Add support for generic function.
const Array& fun_arguments =
Array::CheckedHandle(zone, arguments->NativeArgAt(0));
const Array& fun_arg_names =
Array::CheckedHandle(zone, arguments->NativeArgAt(1));
const Array& fun_args_desc = Array::Handle(
zone, ArgumentsDescriptor::NewBoxed(kTypeArgsLen, fun_arguments.Length(),
fun_arg_names));
const Object& result = Object::Handle(
zone, DartEntry::InvokeClosure(thread, fun_arguments, fun_args_desc));
if (result.IsError()) {
Exceptions::PropagateError(Error::Cast(result));
}
return result.ptr();
}
static bool ClosureEqualsHelper(Zone* zone,
const Closure& receiver,
const Object& other) {
if (receiver.ptr() == other.ptr()) {
return true;
}
if (!other.IsClosure()) {
return false;
}
const auto& other_closure = Closure::Cast(other);
// Closures that are not implicit closures (tear-offs) are unique.
const auto& func_a = Function::Handle(zone, receiver.function());
if (!func_a.IsImplicitClosureFunction()) {
return false;
}
const auto& func_b = Function::Handle(zone, other_closure.function());
if (!func_b.IsImplicitClosureFunction()) {
return false;
}
// If the closure functions are not the same, check the function's name and
// owner, as multiple function objects could exist for the same function due
// to hot reload.
if (func_a.ptr() != func_b.ptr() &&
(func_a.name() != func_b.name() || func_a.Owner() != func_b.Owner() ||
func_a.is_static() != func_b.is_static())) {
return false;
}
// Check that the delayed type argument vectors match.
if (receiver.delayed_type_arguments() !=
other_closure.delayed_type_arguments()) {
// Mismatches should only happen when a generic function is involved.
ASSERT(func_a.IsGeneric() || func_b.IsGeneric());
const auto& type_args_a =
TypeArguments::Handle(zone, receiver.delayed_type_arguments());
const auto& type_args_b =
TypeArguments::Handle(zone, other_closure.delayed_type_arguments());
if (type_args_a.IsNull() || type_args_b.IsNull() ||
(type_args_a.Length() != type_args_b.Length()) ||
!type_args_a.IsEquivalent(type_args_b, TypeEquality::kSyntactical)) {
return false;
}
}
if (!func_a.is_static()) {
// Check that the both receiver instances are the same.
const Context& context_a = Context::Handle(zone, receiver.context());
const Context& context_b = Context::Handle(zone, other_closure.context());
return context_a.At(0) == context_b.At(0);
}
return true;
}
DEFINE_NATIVE_ENTRY(Closure_equals, 0, 2) {
const Closure& receiver =
Closure::CheckedHandle(zone, arguments->NativeArgAt(0));
GET_NATIVE_ARGUMENT(Instance, other, arguments->NativeArgAt(1));
ASSERT(!other.IsNull());
return Bool::Get(ClosureEqualsHelper(zone, receiver, other)).ptr();
}
DEFINE_NATIVE_ENTRY(Closure_computeHash, 0, 1) {
const Closure& receiver =
Closure::CheckedHandle(zone, arguments->NativeArgAt(0));
return Smi::New(receiver.ComputeHash());
}
} // namespace dart