You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: arch.rs
    path of file: ./repos/rust-gpu/crates/spirv-std/src
    
    the code of the file until where you have to start completion: //! SPIR-V Instrinics
//!
//! This module is intended as a low level abstraction over SPIR-V instructions.
//! These functions will typically map to a single instruction, and will perform
//! no additional safety checks beyond type-checking.
#[cfg(target_arch = "spirv")]
use crate::integer::Integer;
use crate::{
    integer::{SignedInteger, UnsignedInteger},
    scalar::Scalar,
    
    unsafe fn index_unchecked_mut(&mut self, index: usize) -> &mut T {
        // FIXME(eddyb) `let mut result = T::default()` uses (for `asm!`), with this.
        let mut result_slot = core::mem::MaybeUninit::uninit();
        asm! {
            "%result = OpAccessChain _ {array_ptr} {index}",
            "OpStore {result_slot} %result",
            array_ptr = in(reg) self,
            index = in(reg) index,
            result_slot = in(reg) result_slot.as_mut_ptr(),
        }
        result_slot.assume_init()
    }