Struct LabelTarget 

pub struct LabelTarget(/* private fields */);

A 32-bit value encoding a label’s arity, jump address, and stack truncation information [arity:2][depth:8][offset:22]

Arity is the result type needed by the target block we are jumping to: arity == 0 (no result) arity == 1 (I32 / F32) arity == 2 (I64 / F64) arity == 3 (unused/invalid)

Depth is the 32-bit width truncation of the stack to perform during this jump.

offset is the pc offset (signed) from the current PC. For forward jumps this will be 0 by default to mark the ‘sentinel’ jump target.

Implementations

impl LabelTarget

pub fn with_jump(self, offset: JumpOffset) -> LabelTarget

pub fn jump(&self) -> JumpOffset

Extract the jump target from the encoded label target

pub fn is_sentinel(&self) -> bool

A jump offset of exactly 0 is the reserved chain-terminator sentinel (see JumpOffset::sentinel). It can never collide with a real jump: forward jumps are strictly positive, loop back-edges strictly negative, and a backpatch chain node never points at itself (offset 0).

pub fn arity(&self) -> LabelArity

Number of 32-bit values to move from the current stack to the result stack

pub fn depth(&self) -> u8

Number of 32-bit values to drop from the stack

Trait Implementations

impl Clone for LabelTarget

fn clone(&self) -> LabelTarget

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for LabelTarget

impl Debug for LabelTarget

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<u32> for LabelTarget

fn from(value: u32) -> Self

Converts to this type from the input type.