AK+LibWasm+LibJS: Disallow Variant.has() on types that aren't contained

Checking for this (and get()'ing it) is always invalid, so let's just
disallow it.
This also finds two bugs where the code is checking for types that can
never actually be in the variant (which was actually a refactor
artifact).
This commit is contained in:
Ali Mohammad Pur 2021-06-02 18:11:48 +04:30 committed by Andreas Kling
parent 87ff76bd57
commit ea7ba34a31
Notes: sideshowbarker 2024-07-18 17:00:48 +09:00
3 changed files with 16 additions and 16 deletions

View file

@ -201,6 +201,12 @@ private:
static constexpr IndexType index_of() { return Detail::index_of<T, IndexType, Ts...>(); }
public:
template<typename T>
static constexpr bool can_contain()
{
return index_of<T>() != invalid_index;
}
template<typename... NewTs>
friend struct Variant;
@ -246,7 +252,7 @@ public:
using Detail::MergeAndDeduplicatePacks<Detail::VariantConstructors<Ts, Variant<Ts...>>...>::MergeAndDeduplicatePacks;
template<typename T, typename StrippedT = RemoveCV<RemoveReference<T>>>
void set(T&& t) requires(index_of<StrippedT>() != invalid_index)
void set(T&& t) requires(can_contain<StrippedT>())
{
constexpr auto new_index = index_of<StrippedT>();
Helper::delete_(m_index, m_data);
@ -255,7 +261,7 @@ public:
}
template<typename T, typename StrippedT = RemoveCV<RemoveReference<T>>>
void set(T&& t, Detail::VariantNoClearTag) requires(index_of<StrippedT>() != invalid_index)
void set(T&& t, Detail::VariantNoClearTag) requires(can_contain<StrippedT>())
{
constexpr auto new_index = index_of<StrippedT>();
new (m_data) StrippedT(forward<T>(t));
@ -263,7 +269,7 @@ public:
}
template<typename T>
T* get_pointer()
T* get_pointer() requires(can_contain<T>())
{
if (index_of<T>() == m_index)
return bit_cast<T*>(&m_data);
@ -271,14 +277,14 @@ public:
}
template<typename T>
T& get()
T& get() requires(can_contain<T>())
{
VERIFY(has<T>());
return *bit_cast<T*>(&m_data);
}
template<typename T>
const T* get_pointer() const
const T* get_pointer() const requires(can_contain<T>())
{
if (index_of<T>() == m_index)
return bit_cast<const T*>(&m_data);
@ -286,14 +292,14 @@ public:
}
template<typename T>
const T& get() const
const T& get() const requires(can_contain<T>())
{
VERIFY(has<T>());
return *bit_cast<const T*>(&m_data);
}
template<typename T>
[[nodiscard]] bool has() const
[[nodiscard]] bool has() const requires(can_contain<T>())
{
return index_of<T>() == m_index;
}
@ -336,12 +342,6 @@ public:
return instance;
}
template<typename T>
static constexpr bool can_contain()
{
return index_of<T>() != invalid_index;
}
private:
static constexpr auto data_size = integer_sequence_generate_array<size_t>(0, IntegerSequence<size_t, sizeof(Ts)...>()).max();
static constexpr auto data_alignment = integer_sequence_generate_array<size_t>(0, IntegerSequence<size_t, alignof(Ts)...>()).max();

View file

@ -1609,7 +1609,7 @@ NonnullRefPtr<VariableDeclaration> Parser::parse_variable_declaration(bool for_l
init = parse_expression(2);
} else if (!for_loop_variable_declaration && declaration_kind == DeclarationKind::Const) {
syntax_error("Missing initializer in 'const' variable declaration");
} else if (target.has<BindingPattern>()) {
} else if (target.has<NonnullRefPtr<BindingPattern>>()) {
syntax_error("Missing initializer in destructuring assignment");
}

View file

@ -482,12 +482,12 @@ void BytecodeInterpreter::interpret(Configuration& configuration, InstructionPoi
return;
}
auto element = table_instance->elements()[index.value()];
if (!element.has_value() || !element->ref().has<FunctionAddress>()) {
if (!element.has_value() || !element->ref().has<Reference::Func>()) {
dbgln("LibWasm: call_indirect attempted with invalid address element (not a function)");
m_do_trap = true;
return;
}
auto address = element->ref().get<FunctionAddress>();
auto address = element->ref().get<Reference::Func>().address;
dbgln_if(WASM_TRACE_DEBUG, "call_indirect({} -> {})", index.value(), address.value());
call_address(configuration, address);
return;