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#[cfg(feature = "simd")]
use crate::core::simd::{ImmLaneIdx16, ImmLaneIdx2, ImmLaneIdx4, ImmLaneIdx8};
#[cfg(all(feature = "simd", doc))]
use crate::core::V128;
use crate::{core::TrapCode, index::*, primitive::Offset64Hi, *};
use ::core::num::{NonZeroI32, NonZeroI64, NonZeroU32, NonZeroU64};
macro_rules! define_enum {
(
$(
$( #[doc = $doc:literal] )*
#[snake_name($snake_name:ident)]
$name:ident
$(
{
$(
@ $result_name:ident: $result_ty:ty,
)?
$(
$( #[$field_docs:meta] )*
$field_name:ident: $field_ty:ty
),*
$(,)?
}
)?
),* $(,)?
) => {
/// A Wasmi instruction.
///
/// Wasmi instructions are composed of so-called instruction words.
/// This type represents all such words and for simplicity we call the type [`Op`], still.
///
/// Most instructions are composed of a single instruction word. An example of
/// this is [`Op::I32Add`]. However, some instructions, like the `select` instructions
/// are composed of two or more instruction words.
///
/// The Wasmi bytecode translation makes sure that instructions always appear in valid sequences.
/// The Wasmi executor relies on the guarantees that the Wasmi translator provides.
///
/// The documentation of each [`Op`] describes its encoding in the
/// `#Encoding` section of its documentation if it requires more than a single
/// instruction for its encoding.
#[derive(Debug)]
#[non_exhaustive]
#[repr(u16)]
pub enum Op {
$(
$( #[doc = $doc] )*
$name
$(
{
$(
/// The register(s) storing the result of the instruction.
$result_name: $result_ty,
)?
$(
$( #[$field_docs] )*
$field_name: $field_ty
),*
}
)?
),*
}
impl Op {
$(
#[doc = concat!("Creates a new [`Op::", stringify!($name), "`].")]
pub fn $snake_name(
$(
$( $result_name: impl Into<$result_ty>, )?
$( $field_name: impl Into<$field_ty> ),*
)?
) -> Self {
Self::$name {
$(
$( $result_name: $result_name.into(), )?
$( $field_name: $field_name.into() ),*
)?
}
}
)*
}
impl<'a> $crate::visit_results::ResultsVisitor for &'a mut Op {
fn host_visitor<V: VisitResults>(self, visitor: &mut V) {
match self {
$(
Op::$name { $( $( $result_name, )? .. )? } => {
$(
$( $result_name.host_visitor(visitor); )?
)?
}
)*
}
}
}
};
}
for_each_op::for_each_op!(define_enum);
impl Copy for Op {}
impl Clone for Op {
fn clone(&self) -> Self {
*self
}
}
impl Op {
/// Creates a new [`Op::ReturnSlot2`] for the given [`Slot`] indices.
pub fn return_reg2_ext(reg0: impl Into<Slot>, reg1: impl Into<Slot>) -> Self {
Self::return_reg2([reg0.into(), reg1.into()])
}
/// Creates a new [`Op::ReturnSlot3`] for the given [`Slot`] indices.
pub fn return_reg3_ext(
reg0: impl Into<Slot>,
reg1: impl Into<Slot>,
reg2: impl Into<Slot>,
) -> Self {
Self::return_reg3([reg0.into(), reg1.into(), reg2.into()])
}
/// Creates a new [`Op::ReturnMany`] for the given [`Slot`] indices.
pub fn return_many_ext(
reg0: impl Into<Slot>,
reg1: impl Into<Slot>,
reg2: impl Into<Slot>,
) -> Self {
Self::return_many([reg0.into(), reg1.into(), reg2.into()])
}
/// Creates a new [`Op::Copy2`].
pub fn copy2_ext(results: SlotSpan, value0: impl Into<Slot>, value1: impl Into<Slot>) -> Self {
let span = FixedSlotSpan::new(results).unwrap_or_else(|_| {
panic!("encountered invalid `results` `SlotSpan` for `Copy2`: {results:?}")
});
Self::copy2(span, [value0.into(), value1.into()])
}
/// Creates a new [`Op::CopyMany`].
pub fn copy_many_ext(
results: SlotSpan,
head0: impl Into<Slot>,
head1: impl Into<Slot>,
) -> Self {
Self::copy_many(results, [head0.into(), head1.into()])
}
/// Creates a new [`Op::Slot2`] instruction parameter.
pub fn slot2_ext(reg0: impl Into<Slot>, reg1: impl Into<Slot>) -> Self {
Self::slot2([reg0.into(), reg1.into()])
}
/// Creates a new [`Op::Slot3`] instruction parameter.
pub fn slot3_ext(reg0: impl Into<Slot>, reg1: impl Into<Slot>, reg2: impl Into<Slot>) -> Self {
Self::slot3([reg0.into(), reg1.into(), reg2.into()])
}
/// Creates a new [`Op::SlotList`] instruction parameter.
pub fn slot_list_ext(
reg0: impl Into<Slot>,
reg1: impl Into<Slot>,
reg2: impl Into<Slot>,
) -> Self {
Self::slot_list([reg0.into(), reg1.into(), reg2.into()])
}
/// Creates a new [`Op::SlotAndImm32`] from the given `reg` and `offset_hi`.
pub fn slot_and_offset_hi(slot: impl Into<Slot>, offset_hi: Offset64Hi) -> Self {
Self::slot_and_imm32(slot, offset_hi.0)
}
/// Returns `Some` [`Slot`] and [`Offset64Hi`] if encoded properly.
///
/// # Errors
///
/// Returns back `self` if it was an incorrect [`Op`].
/// This allows for a better error message to inform the user.
pub fn filter_register_and_offset_hi(self) -> Result<(Slot, Offset64Hi), Self> {
if let Op::SlotAndImm32 { slot, imm } = self {
return Ok((slot, Offset64Hi(u32::from(imm))));
}
Err(self)
}
/// Creates a new [`Op::SlotAndImm32`] from the given `reg` and `offset_hi`.
pub fn slot_and_lane<LaneType>(slot: impl Into<Slot>, lane: LaneType) -> Self
where
LaneType: Into<u8>,
{
Self::slot_and_imm32(slot, u32::from(lane.into()))
}
/// Returns `Some` [`Slot`] and a `lane` index if encoded properly.
///
/// # Errors
///
/// Returns back `self` if it was an incorrect [`Op`].
/// This allows for a better error message to inform the user.
pub fn filter_register_and_lane<LaneType>(self) -> Result<(Slot, LaneType), Self>
where
LaneType: TryFrom<u8>,
{
if let Op::SlotAndImm32 { slot, imm } = self {
let lane_index = u32::from(imm) as u8;
let Ok(lane) = LaneType::try_from(lane_index) else {
panic!("encountered out of bounds lane index: {}", lane_index)
};
return Ok((slot, lane));
}
Err(self)
}
/// Creates a new [`Op::Imm16AndImm32`] from the given `value` and `offset_hi`.
pub fn imm16_and_offset_hi(value: impl Into<AnyConst16>, offset_hi: Offset64Hi) -> Self {
Self::imm16_and_imm32(value, offset_hi.0)
}
/// Returns `Some` [`Slot`] and [`Offset64Hi`] if encoded properly.
///
/// # Errors
///
/// Returns back `self` if it was an incorrect [`Op`].
/// This allows for a better error message to inform the user.
pub fn filter_imm16_and_offset_hi<T>(self) -> Result<(T, Offset64Hi), Self>
where
T: From<AnyConst16>,
{
if let Op::Imm16AndImm32 { imm16, imm32 } = self {
return Ok((T::from(imm16), Offset64Hi(u32::from(imm32))));
}
Err(self)
}
/// Creates a new [`Op::Imm16AndImm32`] from the given `lane` and `memory` index.
pub fn lane_and_memory_index(value: impl Into<u8>, memory: Memory) -> Self {
Self::imm16_and_imm32(u16::from(value.into()), u32::from(memory))
}
/// Returns `Some` lane and [`index::Memory`] if encoded properly.
///
/// # Errors
///
/// Returns back `self` if it was an incorrect [`Op`].
/// This allows for a better error message to inform the user.
pub fn filter_lane_and_memory<LaneType>(self) -> Result<(LaneType, index::Memory), Self>
where
LaneType: TryFrom<u8>,
{
if let Op::Imm16AndImm32 { imm16, imm32 } = self {
let Ok(lane) = LaneType::try_from(i16::from(imm16) as u16 as u8) else {
return Err(self);
};
return Ok((lane, index::Memory::from(u32::from(imm32))));
}
Err(self)
}
}
#[test]
fn size_of() {
// Note: In case this test starts failing:
//
// There currently is a bug in the Rust compiler that causes
// Rust `enum` definitions with `#[repr(uN)]` to be incorrectly
// sized: https://github.com/rust-lang/rust/issues/53657
//
// Until that bug is fixed we need to order the `enum` variant
// fields in a precise order to end up with the correct `enum` size.
assert_eq!(::core::mem::size_of::<Op>(), 8);
assert_eq!(::core::mem::align_of::<Op>(), 4);
}