Enum Callee 

pub enum Callee {
    Named(Symbol),
    Through(Reg),
}

What a call goes to.

The whole of the difference between the two calls. Everything else about them, which is what they pass and what comes back and which registers they destroy, is the signature’s answer and is the same answer either way.

Variants

Named(Symbol)

A name, which the linker resolves.

Through(Reg)

An address in a register, which nothing resolves because there is nothing to resolve: the value is not known until the program runs.

The register is unconstrained, and it has to be, because every register the convention does not preserve is one this instruction writes and every register an argument travels in is spoken for. What is left is the registers the callee has to put back, which is where the allocator will put the address, and it is the right answer for the same reason it is the only one.

Trait Implementations

impl Clone for Callee

fn clone(&self) -> Callee

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Callee

impl Debug for Callee

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

Formats the value using the given formatter.

impl Eq for Callee

impl PartialEq for Callee

fn eq(&self, other: &Callee) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Callee