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//! Working with GC `array` objects.
use crate::runtime::vm::VMGcRef;
use crate::store::StoreId;
use crate::vm::{GcArrayLayout, GcLayout, VMArrayRef, VMGcHeader};
use crate::{
prelude::*,
store::{AutoAssertNoGc, StoreContextMut, StoreOpaque},
ArrayType, AsContext, AsContextMut, GcHeapOutOfMemory, GcRefImpl, GcRootIndex, HeapType,
ManuallyRooted, RefType, Rooted, Val, ValRaw, ValType, WasmTy,
};
use crate::{AnyRef, FieldType};
use core::mem::{self, MaybeUninit};
use wasmtime_environ::{VMGcKind, VMSharedTypeIndex};
/// An allocator for a particular Wasm GC array type.
///
/// Every `ArrayRefPre` is associated with a particular [`Store`][crate::Store]
/// and a particular [`ArrayType`][crate::ArrayType].
///
/// Reusing an allocator across many allocations amortizes some per-type runtime
/// overheads inside Wasmtime. An `ArrayRefPre` is to `ArrayRef`s as an
/// `InstancePre` is to `Instance`s.
///
/// # Example
///
/// ```
/// use wasmtime::*;
///
/// # fn foo() -> Result<()> {
/// let mut config = Config::new();
/// config.wasm_function_references(true);
/// config.wasm_gc(true);
///
/// let engine = Engine::new(&config)?;
/// let mut store = Store::new(&engine, ());
///
/// // Define an array type.
/// let array_ty = ArrayType::new(
/// store.engine(),
/// FieldType::new(Mutability::Var, ValType::I32.into()),
/// );
///
/// // Create an allocator for the array type.
/// let allocator = ArrayRefPre::new(&mut store, array_ty);
///
/// {
/// let mut scope = RootScope::new(&mut store);
///
/// // Allocate a bunch of instances of our array type using the same
/// // allocator! This is faster than creating a new allocator for each
/// // instance we want to allocate.
/// for i in 0..10 {
/// let len = 42;
/// let elem = Val::I32(36);
/// ArrayRef::new(&mut scope, &allocator, &elem, len)?;
/// }
/// }
/// # Ok(())
/// # }
/// # foo().unwrap();
/// ```
pub struct ArrayRefPre {
store_id: StoreId,
ty: ArrayType,
}
impl ArrayRefPre {
/// Create a new `ArrayRefPre` that is associated with the given store
/// and type.
pub fn new(mut store: impl AsContextMut, ty: ArrayType) -> Self {
Self::_new(store.as_context_mut().0, ty)
}
pub(crate) fn _new(store: &mut StoreOpaque, ty: ArrayType) -> Self {
store.insert_gc_host_alloc_type(ty.registered_type().clone());
let store_id = store.id();
ArrayRefPre { store_id, ty }
}
pub(crate) fn layout(&self) -> &GcArrayLayout {
self.ty
.registered_type()
.layout()
.expect("array types have a layout")
.unwrap_array()
}
pub(crate) fn type_index(&self) -> VMSharedTypeIndex {
self.ty.registered_type().index()
}
}
/// A reference to a GC-managed `array` instance.
///
/// WebAssembly `array`s are a sequence of elements of some homogeneous
/// type. The elements length is determined at allocation time — two instances
/// of the same array type may have different lengths — but, once allocated, an
/// array's length can never be resized. An array's elements are mutable or
/// constant, depending on the array's type. This determines whether any array
/// element can be assigned a new value or not. Each element is either an
/// unpacked [`Val`][crate::Val] or a packed 8-/16-bit integer. Array elements
/// are dynamically accessed via indexing; out-of-bounds accesses result in
/// traps.
///
/// Like all WebAssembly references, these are opaque and unforgeable to Wasm:
/// they cannot be faked and Wasm cannot, for example, cast the integer
/// `0x12345678` into a reference, pretend it is a valid `arrayref`, and trick
/// the host into dereferencing it and segfaulting or worse.
///
/// Note that you can also use `Rooted<ArrayRef>` and `ManuallyRooted<ArrayRef>`
/// as a type parameter with [`Func::typed`][crate::Func::typed]- and
/// [`Func::wrap`][crate::Func::wrap]-style APIs.
///
/// # Example
///
/// ```
/// use wasmtime::*;
///
/// # fn foo() -> Result<()> {
/// let mut config = Config::new();
/// config.wasm_function_references(true);
/// config.wasm_gc(true);
///
/// let engine = Engine::new(&config)?;
/// let mut store = Store::new(&engine, ());
///
/// // Define the type for an array of `i32`s.
/// let array_ty = ArrayType::new(
/// store.engine(),
/// FieldType::new(Mutability::Var, ValType::I32.into()),
/// );
///
/// // Create an allocator for the array type.
/// let allocator = ArrayRefPre::new(&mut store, array_ty);
///
/// {
/// let mut scope = RootScope::new(&mut store);
///
/// // Allocate an instance of the array type.
/// let len = 36;
/// let elem = Val::I32(42);
/// let my_array = match ArrayRef::new(&mut scope, &allocator, &elem, len) {
/// Ok(s) => s,
///
/// // If the heap is out of memory, then do a GC to free up some space
/// // and try again.
/// Err(e) if e.is::<GcHeapOutOfMemory<()>>() => {
/// // Do a GC! Note: in an async context, you'd want to do
/// // `scope.as_context_mut().gc_async().await`.
/// scope.as_context_mut().gc();
///
/// // Try again. If the GC heap is still out of memory, then we
/// // weren't able to free up resources for this allocation, so
/// // propagate the error.
/// ArrayRef::new(&mut scope, &allocator, &elem, len)?
/// }
///
/// // Propagate any other kind of error.
/// Err(e) => return Err(e),
/// };
///
/// // That instance's elements should have the initial value.
/// for i in 0..len {
/// let val = my_array.get(&mut scope, i)?.unwrap_i32();
/// assert_eq!(val, 42);
/// }
///
/// // We can set an element to a new value because the type was defined with
/// // mutable elements (as opposed to const).
/// my_array.set(&mut scope, 3, Val::I32(1234))?;
/// let new_val = my_array.get(&mut scope, 3)?.unwrap_i32();
/// assert_eq!(new_val, 1234);
/// }
/// # Ok(())
/// # }
/// # foo().unwrap();
/// ```
#[derive(Debug)]
#[repr(transparent)]
pub struct ArrayRef {
pub(super) inner: GcRootIndex,
}
unsafe impl GcRefImpl for ArrayRef {
#[allow(private_interfaces)]
fn transmute_ref(index: &GcRootIndex) -> &Self {
// Safety: `ArrayRef` is a newtype of a `GcRootIndex`.
let me: &Self = unsafe { mem::transmute(index) };
// Assert we really are just a newtype of a `GcRootIndex`.
assert!(matches!(
me,
Self {
inner: GcRootIndex { .. },
}
));
me
}
}
impl Rooted<ArrayRef> {
/// Upcast this `arrayref` into an `anyref`.
#[inline]
pub fn to_anyref(self) -> Rooted<AnyRef> {
self.unchecked_cast()
}
}
impl ManuallyRooted<ArrayRef> {
/// Upcast this `arrayref` into an `anyref`.
#[inline]
pub fn to_anyref(self) -> ManuallyRooted<AnyRef> {
self.unchecked_cast()
}
}
impl ArrayRef {
/// Allocate a new `array` of the given length, with every element
/// initialized to `elem`.
///
/// For example, `ArrayRef::new(ctx, pre, &Val::I64(9), 3)` allocates the
/// array `[9, 9, 9]`.
///
/// This is similar to the `array.new` instruction.
///
/// # Errors
///
/// If the given `elem` value's type does not match the `allocator`'s array
/// type's element type, an error is returned.
///
/// If the allocation cannot be satisfied because the GC heap is currently
/// out of memory, but performing a garbage collection might free up space
/// such that retrying the allocation afterwards might succeed, then a
/// [`GcHeapOutOfMemory<()>`][crate::GcHeapOutOfMemory] error is returned.
///
/// # Panics
///
/// Panics if either the allocator or the `elem` value is not associated
/// with the given store.
pub fn new(
mut store: impl AsContextMut,
allocator: &ArrayRefPre,
elem: &Val,
len: u32,
) -> Result<Rooted<ArrayRef>> {
Self::_new(store.as_context_mut().0, allocator, elem, len)
}
pub(crate) fn _new(
store: &mut StoreOpaque,
allocator: &ArrayRefPre,
elem: &Val,
len: u32,
) -> Result<Rooted<ArrayRef>> {
assert_eq!(
store.id(),
allocator.store_id,
"attempted to use a `ArrayRefPre` with the wrong store"
);
// Type check the initial element value against the element type.
elem.ensure_matches_ty(store, allocator.ty.element_type().unpack())
.context("element type mismatch")?;
return Self::_new_unchecked(store, allocator, RepeatN(elem, len));
// NB: Can't use `iter::repeat(elem).take(len)` above because that
// doesn't implement `ExactSizeIterator`.
struct RepeatN<'a>(&'a Val, u32);
impl<'a> Iterator for RepeatN<'a> {
type Item = &'a Val;
fn next(&mut self) -> Option<Self::Item> {
if self.1 == 0 {
None
} else {
self.1 -= 1;
Some(self.0)
}
}
fn size_hint(&self) -> (usize, Option<usize>) {
let len = self.len();
(len, Some(len))
}
}
impl ExactSizeIterator for RepeatN<'_> {
fn len(&self) -> usize {
usize::try_from(self.1).unwrap()
}
}
}
/// Allocate a new array of the given elements, without checking that the
/// elements' types match the array's element type.
fn _new_unchecked<'a>(
store: &mut StoreOpaque,
allocator: &ArrayRefPre,
elems: impl ExactSizeIterator<Item = &'a Val>,
) -> Result<Rooted<ArrayRef>> {
let len = u32::try_from(elems.len()).unwrap();
// Allocate the array and write each field value into the appropriate
// offset.
let arrayref = store
.gc_store_mut()?
.alloc_uninit_array(allocator.type_index(), len, allocator.layout())
.err2anyhow()
.context("unrecoverable error when allocating new `arrayref`")?
.ok_or_else(|| GcHeapOutOfMemory::new(()))
.err2anyhow()?;
// From this point on, if we get any errors, then the array is not
// fully initialized, so we need to eagerly deallocate it before the
// next GC where the collector might try to interpret one of the
// uninitialized fields as a GC reference.
let mut store = AutoAssertNoGc::new(store);
match (|| {
let elem_ty = allocator.ty.element_type();
for (i, elem) in elems.enumerate() {
let i = u32::try_from(i).unwrap();
debug_assert!(i < len);
arrayref.initialize_elem(&mut store, allocator.layout(), &elem_ty, i, *elem)?;
}
Ok(())
})() {
Ok(()) => Ok(Rooted::new(&mut store, arrayref.into())),
Err(e) => {
store.gc_store_mut()?.dealloc_uninit_array(arrayref);
Err(e)
}
}
}
/// Allocate a new `array` containing the given elements.
///
/// For example, `ArrayRef::new_fixed(ctx, pre, &[Val::I64(4), Val::I64(5),
/// Val::I64(6)])` allocates the array `[4, 5, 6]`.
///
/// This is similar to the `array.new_fixed` instruction.
///
/// # Errors
///
/// If any of the `elems` values' type does not match the `allocator`'s
/// array type's element type, an error is returned.
///
/// If the allocation cannot be satisfied because the GC heap is currently
/// out of memory, but performing a garbage collection might free up space
/// such that retrying the allocation afterwards might succeed, then a
/// [`GcHeapOutOfMemory<()>`][crate::GcHeapOutOfMemory] error is returned.
///
/// # Panics
///
/// Panics if the allocator or any of the `elems` values are not associated
/// with the given store.
pub fn new_fixed(
mut store: impl AsContextMut,
allocator: &ArrayRefPre,
elems: &[Val],
) -> Result<Rooted<ArrayRef>> {
Self::_new_fixed(store.as_context_mut().0, allocator, elems)
}
pub(crate) fn _new_fixed(
store: &mut StoreOpaque,
allocator: &ArrayRefPre,
elems: &[Val],
) -> Result<Rooted<ArrayRef>> {
assert_eq!(
store.id(),
allocator.store_id,
"attempted to use a `ArrayRefPre` with the wrong store"
);
// Type check the elements against the element type.
for elem in elems {
elem.ensure_matches_ty(store, allocator.ty.element_type().unpack())
.context("element type mismatch")?;
}
return Self::_new_unchecked(store, allocator, elems.iter());
}
#[inline]
pub(crate) fn comes_from_same_store(&self, store: &StoreOpaque) -> bool {
self.inner.comes_from_same_store(store)
}
/// Get this `arrayref`'s type.
///
/// # Errors
///
/// Return an error if this reference has been unrooted.
///
/// # Panics
///
/// Panics if this reference is associated with a different store.
pub fn ty(&self, store: impl AsContext) -> Result<ArrayType> {
self._ty(store.as_context().0)
}
pub(crate) fn _ty(&self, store: &StoreOpaque) -> Result<ArrayType> {
assert!(self.comes_from_same_store(store));
let index = self.type_index(store)?;
Ok(ArrayType::from_shared_type_index(store.engine(), index))
}
/// Does this `arrayref` match the given type?
///
/// That is, is this array's type a subtype of the given type?
///
/// # Errors
///
/// Return an error if this reference has been unrooted.
///
/// # Panics
///
/// Panics if this reference is associated with a different store or if the
/// type is not associated with the store's engine.
pub fn matches_ty(&self, store: impl AsContext, ty: &ArrayType) -> Result<bool> {
self._matches_ty(store.as_context().0, ty)
}
pub(crate) fn _matches_ty(&self, store: &StoreOpaque, ty: &ArrayType) -> Result<bool> {
assert!(self.comes_from_same_store(store));
Ok(self._ty(store)?.matches(ty))
}
pub(crate) fn ensure_matches_ty(&self, store: &StoreOpaque, ty: &ArrayType) -> Result<()> {
if !self.comes_from_same_store(store) {
bail!("function used with wrong store");
}
if self._matches_ty(store, ty)? {
Ok(())
} else {
let actual_ty = self._ty(store)?;
bail!("type mismatch: expected `(ref {ty})`, found `(ref {actual_ty})`")
}
}
/// Get the length of this array.
///
/// # Errors
///
/// Return an error if this reference has been unrooted.
///
/// # Panics
///
/// Panics if this reference is associated with a different store.
pub fn len(&self, store: impl AsContext) -> Result<u32> {
self._len(store.as_context().0)
}
pub(crate) fn _len(&self, store: &StoreOpaque) -> Result<u32> {
assert!(self.comes_from_same_store(store));
let gc_ref = self.inner.try_gc_ref(store)?;
debug_assert!({
let header = store.gc_store()?.header(gc_ref);
header.kind().matches(VMGcKind::ArrayRef)
});
let arrayref = gc_ref.as_arrayref_unchecked();
Ok(arrayref.len(store))
}
/// Get the values of this array's elements.
///
/// Note that `i8` and `i16` field values are zero-extended into
/// `Val::I32(_)`s.
///
/// # Errors
///
/// Return an error if this reference has been unrooted.
///
/// # Panics
///
/// Panics if this reference is associated with a different store.
pub fn elems<'a, T: 'a>(
&'a self,
store: impl Into<StoreContextMut<'a, T>>,
) -> Result<impl ExactSizeIterator<Item = Val> + 'a> {
self._elems(store.into().0)
}
pub(crate) fn _elems<'a>(
&'a self,
store: &'a mut StoreOpaque,
) -> Result<impl ExactSizeIterator<Item = Val> + 'a> {
assert!(self.comes_from_same_store(store));
let store = AutoAssertNoGc::new(store);
let gc_ref = self.inner.try_gc_ref(&store)?;
let header = store.gc_store()?.header(gc_ref);
debug_assert!(header.kind().matches(VMGcKind::ArrayRef));
let len = self._len(&store)?;
return Ok(Elems {
arrayref: self,
store,
index: 0,
len,
});
struct Elems<'a, 'b> {
arrayref: &'a ArrayRef,
store: AutoAssertNoGc<'b>,
index: u32,
len: u32,
}
impl Iterator for Elems<'_, '_> {
type Item = Val;
#[inline]
fn next(&mut self) -> Option<Self::Item> {
let i = self.index;
debug_assert!(i <= self.len);
if i >= self.len {
return None;
}
self.index += 1;
Some(self.arrayref._get(&mut self.store, i).unwrap())
}
#[inline]
fn size_hint(&self) -> (usize, Option<usize>) {
let len = self.len - self.index;
let len = usize::try_from(len).unwrap();
(len, Some(len))
}
}
impl ExactSizeIterator for Elems<'_, '_> {
#[inline]
fn len(&self) -> usize {
let len = self.len - self.index;
usize::try_from(len).unwrap()
}
}
}
fn header<'a>(&self, store: &'a AutoAssertNoGc<'_>) -> Result<&'a VMGcHeader> {
assert!(self.comes_from_same_store(&store));
let gc_ref = self.inner.try_gc_ref(store)?;
Ok(store.gc_store()?.header(gc_ref))
}
fn arrayref<'a>(&self, store: &'a AutoAssertNoGc<'_>) -> Result<&'a VMArrayRef> {
assert!(self.comes_from_same_store(&store));
let gc_ref = self.inner.try_gc_ref(store)?;
debug_assert!(self.header(store)?.kind().matches(VMGcKind::ArrayRef));
Ok(gc_ref.as_arrayref_unchecked())
}
fn layout(&self, store: &AutoAssertNoGc<'_>) -> Result<GcArrayLayout> {
assert!(self.comes_from_same_store(&store));
let type_index = self.type_index(store)?;
let layout = store
.engine()
.signatures()
.layout(type_index)
.expect("array types should have GC layouts");
match layout {
GcLayout::Array(a) => Ok(a),
GcLayout::Struct(_) => unreachable!(),
}
}
fn field_ty(&self, store: &StoreOpaque) -> Result<FieldType> {
let ty = self._ty(store)?;
Ok(ty.field_type())
}
/// Get this array's `index`th element.
///
/// Note that `i8` and `i16` field values are zero-extended into
/// `Val::I32(_)`s.
///
/// # Errors
///
/// Returns an `Err(_)` if the index is out of bounds or this reference has
/// been unrooted.
///
/// # Panics
///
/// Panics if this reference is associated with a different store.
pub fn get(&self, mut store: impl AsContextMut, index: u32) -> Result<Val> {
let mut store = AutoAssertNoGc::new(store.as_context_mut().0);
self._get(&mut store, index)
}
pub(crate) fn _get(&self, store: &mut AutoAssertNoGc<'_>, index: u32) -> Result<Val> {
assert!(
self.comes_from_same_store(store),
"attempted to use an array with the wrong store",
);
let arrayref = self.arrayref(store)?.unchecked_copy();
let field_ty = self.field_ty(store)?;
let layout = self.layout(store)?;
let len = arrayref.len(store);
ensure!(
index < len,
"index out of bounds: the length is {len} but the index is {index}"
);
Ok(arrayref.read_elem(store, &layout, field_ty.element_type(), index))
}
/// Set this array's `index`th element.
///
/// # Errors
///
/// Returns an error in the following scenarios:
///
/// * When given a value of the wrong type, such as trying to write an `f32`
/// value into an array of `i64` elements.
///
/// * When the array elements are not mutable.
///
/// * When `index` is not within the range `0..self.len(ctx)`.
///
/// * When `value` is a GC reference that has since been unrooted.
///
/// # Panics
///
/// Panics if either this reference or the given `value` is associated with
/// a different store.
pub fn set(&self, mut store: impl AsContextMut, index: u32, value: Val) -> Result<()> {
self._set(store.as_context_mut().0, index, value)
}
pub(crate) fn _set(&self, store: &mut StoreOpaque, index: u32, value: Val) -> Result<()> {
assert!(
self.comes_from_same_store(store),
"attempted to use an array with the wrong store",
);
assert!(
value.comes_from_same_store(store),
"attempted to use a value with the wrong store",
);
let mut store = AutoAssertNoGc::new(store);
let field_ty = self.field_ty(&store)?;
ensure!(
field_ty.mutability().is_var(),
"cannot set element {index}: array elements are not mutable"
);
value
.ensure_matches_ty(&store, &field_ty.element_type().unpack())
.with_context(|| format!("cannot set element {index}: type mismatch"))?;
let layout = self.layout(&store)?;
let arrayref = self.arrayref(&store)?.unchecked_copy();
let len = arrayref.len(&store);
ensure!(
index < len,
"index out of bounds: the length is {len} but the index is {index}"
);
arrayref.write_elem(&mut store, &layout, field_ty.element_type(), index, value)
}
pub(crate) fn type_index(&self, store: &StoreOpaque) -> Result<VMSharedTypeIndex> {
let gc_ref = self.inner.try_gc_ref(store)?;
let header = store.gc_store()?.header(gc_ref);
debug_assert!(header.kind().matches(VMGcKind::ArrayRef));
Ok(header.ty().expect("arrayrefs should have concrete types"))
}
/// Create a new `Rooted<ArrayRef>` from the given GC reference.
///
/// `gc_ref` should point to a valid `arrayref` and should belong to the
/// store's GC heap. Failure to uphold these invariants is memory safe but
/// will lead to general incorrectness such as panics or wrong results.
pub(crate) fn from_cloned_gc_ref(
store: &mut AutoAssertNoGc<'_>,
gc_ref: VMGcRef,
) -> Rooted<Self> {
debug_assert!(!gc_ref.is_i31());
Rooted::new(store, gc_ref)
}
}
unsafe impl WasmTy for Rooted<ArrayRef> {
#[inline]
fn valtype() -> ValType {
ValType::Ref(RefType::new(false, HeapType::Array))
}
#[inline]
fn compatible_with_store(&self, store: &StoreOpaque) -> bool {
self.comes_from_same_store(store)
}
#[inline]
fn dynamic_concrete_type_check(
&self,
store: &StoreOpaque,
_nullable: bool,
ty: &HeapType,
) -> Result<()> {
match ty {
HeapType::Any | HeapType::Eq | HeapType::Array => Ok(()),
HeapType::ConcreteArray(ty) => self.ensure_matches_ty(store, ty),
HeapType::Extern
| HeapType::NoExtern
| HeapType::Func
| HeapType::ConcreteFunc(_)
| HeapType::NoFunc
| HeapType::I31
| HeapType::Struct
| HeapType::ConcreteStruct(_)
| HeapType::None => bail!(
"type mismatch: expected `(ref {ty})`, got `(ref {})`",
self._ty(store)?,
),
}
}
fn store(self, store: &mut AutoAssertNoGc<'_>, ptr: &mut MaybeUninit<ValRaw>) -> Result<()> {
self.wasm_ty_store(store, ptr, ValRaw::anyref)
}
unsafe fn load(store: &mut AutoAssertNoGc<'_>, ptr: &ValRaw) -> Self {
Self::wasm_ty_load(store, ptr.get_anyref(), ArrayRef::from_cloned_gc_ref)
}
}
unsafe impl WasmTy for Option<Rooted<ArrayRef>> {
#[inline]
fn valtype() -> ValType {
ValType::ARRAYREF
}
#[inline]
fn compatible_with_store(&self, store: &StoreOpaque) -> bool {
self.map_or(true, |x| x.comes_from_same_store(store))
}
#[inline]
fn dynamic_concrete_type_check(
&self,
store: &StoreOpaque,
nullable: bool,
ty: &HeapType,
) -> Result<()> {
match self {
Some(s) => Rooted::<ArrayRef>::dynamic_concrete_type_check(s, store, nullable, ty),
None => {
ensure!(
nullable,
"expected a non-null reference, but found a null reference"
);
Ok(())
}
}
}
#[inline]
fn is_vmgcref_and_points_to_object(&self) -> bool {
self.is_some()
}
fn store(self, store: &mut AutoAssertNoGc<'_>, ptr: &mut MaybeUninit<ValRaw>) -> Result<()> {
<Rooted<ArrayRef>>::wasm_ty_option_store(self, store, ptr, ValRaw::anyref)
}
unsafe fn load(store: &mut AutoAssertNoGc<'_>, ptr: &ValRaw) -> Self {
<Rooted<ArrayRef>>::wasm_ty_option_load(
store,
ptr.get_anyref(),
ArrayRef::from_cloned_gc_ref,
)
}
}
unsafe impl WasmTy for ManuallyRooted<ArrayRef> {
#[inline]
fn valtype() -> ValType {
ValType::Ref(RefType::new(false, HeapType::Array))
}
#[inline]
fn compatible_with_store(&self, store: &StoreOpaque) -> bool {
self.comes_from_same_store(store)
}
#[inline]
fn dynamic_concrete_type_check(
&self,
store: &StoreOpaque,
_: bool,
ty: &HeapType,
) -> Result<()> {
match ty {
HeapType::Any | HeapType::Eq | HeapType::Array => Ok(()),
HeapType::ConcreteArray(ty) => self.ensure_matches_ty(store, ty),
HeapType::Extern
| HeapType::NoExtern
| HeapType::Func
| HeapType::ConcreteFunc(_)
| HeapType::NoFunc
| HeapType::I31
| HeapType::Struct
| HeapType::ConcreteStruct(_)
| HeapType::None => bail!(
"type mismatch: expected `(ref {ty})`, got `(ref {})`",
self._ty(store)?,
),
}
}
fn store(self, store: &mut AutoAssertNoGc<'_>, ptr: &mut MaybeUninit<ValRaw>) -> Result<()> {
self.wasm_ty_store(store, ptr, ValRaw::anyref)
}
unsafe fn load(store: &mut AutoAssertNoGc<'_>, ptr: &ValRaw) -> Self {
Self::wasm_ty_load(store, ptr.get_anyref(), ArrayRef::from_cloned_gc_ref)
}
}
unsafe impl WasmTy for Option<ManuallyRooted<ArrayRef>> {
#[inline]
fn valtype() -> ValType {
ValType::ARRAYREF
}
#[inline]
fn compatible_with_store(&self, store: &StoreOpaque) -> bool {
self.as_ref()
.map_or(true, |x| x.comes_from_same_store(store))
}
#[inline]
fn dynamic_concrete_type_check(
&self,
store: &StoreOpaque,
nullable: bool,
ty: &HeapType,
) -> Result<()> {
match self {
Some(s) => {
ManuallyRooted::<ArrayRef>::dynamic_concrete_type_check(s, store, nullable, ty)
}
None => {
ensure!(
nullable,
"expected a non-null reference, but found a null reference"
);
Ok(())
}
}
}
#[inline]
fn is_vmgcref_and_points_to_object(&self) -> bool {
self.is_some()
}
fn store(self, store: &mut AutoAssertNoGc<'_>, ptr: &mut MaybeUninit<ValRaw>) -> Result<()> {
<ManuallyRooted<ArrayRef>>::wasm_ty_option_store(self, store, ptr, ValRaw::anyref)
}
unsafe fn load(store: &mut AutoAssertNoGc<'_>, ptr: &ValRaw) -> Self {
<ManuallyRooted<ArrayRef>>::wasm_ty_option_load(
store,
ptr.get_anyref(),
ArrayRef::from_cloned_gc_ref,
)
}
}