Method store_flat

crates/test-util/src/component_fuzz.rs:264–322

Generates text format wasm into `s` to store a value of this type, in its flat representation stored in the `locals` provided, to the local named `ptr` at the `offset` provided. This will register helper functions necessary in `helpers`. The `locals` iterator will be advanced for all locals consumed by this store operation.

(
        &'a self,
        s: &mut String,
        ptr: &str,
        offset: u32,
        locals: &mut dyn Iterator<Item = FlatSource>,
        helpers: &mut IndexSet<Helper<'a>>,
    )

    /// `locals` iterator will be advanced for all locals consumed by this
    /// store operation.
    fn store_flat<'a>(
        &'a self,
        s: &mut String,
        ptr: &str,
        offset: u32,
        locals: &mut dyn Iterator<Item = FlatSource>,
        helpers: &mut IndexSet<Helper<'a>>,
    ) {
        enum Kind {
            Primitive(&'static str),
            PointerPair,
            Helper,
        }
        let kind = match self {
            Type::Bool | Type::S8 | Type::U8 => Kind::Primitive("i32.store8"),
            Type::S16 | Type::U16 => Kind::Primitive("i32.store16"),
            Type::S32 | Type::U32 | Type::Char => Kind::Primitive("i32.store"),
            Type::S64 | Type::U64 => Kind::Primitive("i64.store"),
            Type::Float32 => Kind::Primitive("f32.store"),
            Type::Float64 => Kind::Primitive("f64.store"),
            Type::String | Type::List(_) | Type::Map(_, _) => Kind::PointerPair,
            Type::Enum(n) if *n <= (1 << 8) => Kind::Primitive("i32.store8"),
            Type::Enum(n) if *n <= (1 << 16) => Kind::Primitive("i32.store16"),
            Type::Enum(_) => Kind::Primitive("i32.store"),
            Type::Flags(n) if *n <= 8 => Kind::Primitive("i32.store8"),
            Type::Flags(n) if *n <= 16 => Kind::Primitive("i32.store16"),
            Type::Flags(n) if *n <= 32 => Kind::Primitive("i32.store"),
            Type::Flags(_) => unreachable!(),
            Type::Record(_)
            | Type::Tuple(_)
            | Type::Variant(_)
            | Type::Option(_)
            | Type::Result { .. } => Kind::Helper,
        };

        match kind {
            Kind::Primitive(op) => uwriteln!(
                s,
                "({op} offset={offset} (local.get {ptr}) {})",
                locals.next().unwrap()
            ),
            Kind::PointerPair => {
                let abi_ptr = locals.next().unwrap();
                let abi_len = locals.next().unwrap();
                uwriteln!(s, "(i32.store offset={offset} (local.get {ptr}) {abi_ptr})",);
                let offset = offset + 4;
                uwriteln!(s, "(i32.store offset={offset} (local.get {ptr}) {abi_len})",);
            }
            Kind::Helper => {
                let (index, _) = helpers.insert_full(Helper(self));
                uwriteln!(s, "(i32.add (local.get {ptr}) (i32.const {offset}))");
                for _ in 0..self.lowered().len() {
                    let i = locals.next().unwrap();
                    uwriteln!(s, "{i}");
                }
                uwriteln!(s, "call $store_helper_{index}");
            }
        }