Function load_list

crates/wasmtime/src/runtime/component/values.rs:955–983

(cx: &mut LiftContext<'_>, ty: TypeListIndex, ptr: usize, len: usize)

}

fn load_list(cx: &mut LiftContext<'_>, ty: TypeListIndex, ptr: usize, len: usize) -> Result<Val> {
    let elem = cx.types[ty].element;
    let abi = cx.types.canonical_abi(&elem);
    let element_size = usize::try_from(abi.size32).unwrap();
    let element_alignment = abi.align32;

    match len
        .checked_mul(element_size)
        .and_then(|len| ptr.checked_add(len))
    {
        Some(n) if n <= cx.memory().len() => cx.consume_fuel_array(len, size_of::<Val>())?,
        _ => bail!("list pointer/length out of bounds of memory"),
    }
    if ptr % usize::try_from(element_alignment)? != 0 {
        bail!("list pointer is not aligned")
    }

    Ok(Val::List(
        (0..len)
            .map(|index| {
                Val::load(
                    cx,
                    elem,
                    &cx.memory()[ptr + (index * element_size)..][..element_size],
                )
            })
            .collect::<Result<_>>()?,
    ))
}

fn load_map(cx: &mut LiftContext<'_>, ty: TypeMapIndex, ptr: usize, len: usize) -> Result<Val> {
    // Maps are stored as list<tuple<k, v>> in canonical ABI