Method reg_use

cranelift/codegen/src/machinst/reg.rs:430–432

Add a register use, at the start of the instruction (`Before` position).

(&mut self, reg: &mut impl AsMut<Reg>)

    /// Add a register use, at the start of the instruction (`Before`
    /// position).
    fn reg_use(&mut self, reg: &mut impl AsMut<Reg>) {
        self.reg_maybe_fixed(reg.as_mut(), OperandKind::Use, OperandPos::Early);
    }

    /// Add a register use, at the end of the instruction (`After` position).
    fn reg_late_use(&mut self, reg: &mut impl AsMut<Reg>) {