What are the existing methods for optimizing performance for the V8 engine?

1. Avoid polymorphic operations.
2. Prefer monomorphic operations.
3. Use hidden classes.
4. Optimize loops.
5. Use object and array literals.
6. Avoid delete, eval, and arguments.
7. Apply use strict.
8. Free unused memory in a timely manner.

// Monomorphic function (faster)
function fastAdd(a, b) {
  return a + b; // V8 can easily optimize addition of the same type
}

// Polymorphic function (slower)
function slowAdd(a, b) {
  return a + b; // V8 cannot predict argument types
}

// Using array literal (faster)
const arr = [1, 2, 3];

// Using Array constructor (may be slower due to polymorphism)
const arr2 = new Array(1, 2, 3);

// Avoid delete
const obj = { a: 1, b: 2 };
obj.b = undefined; // Instead of delete obj.b