384-bit integer implementation in EVM

uint384.yul

object "test" {
code {

// This assumes each limb is 256-bit and the half of the second limb is not dirty.
function add_with_carry_384_orig(x1, x2, y1, y2) -> out1, out2, carry {
   // limb 1
   out1 := add(x1, y1)
   carry := lt(out1, x1)

   // limb 2
   x2 := add(x2, carry)
   carry := lt(x2, carry)
   out2 := add(x2, y2)
   carry := or(carry, lt(out2, x2))
}

// This assumes each limb is 256-bit and the half of the second limb is not dirty.
function add_with_carry_384(x1, x2, y1, y2) -> out1, out2, carry {
  // limb 1
  out1 := add(x1, y1)
  let carry1 := lt(out1, x1)

  // limb 2
  let t := add(x2, y2)
  let carry2 := lt(t, x2)

  out2 := add(t, carry1)
  carry := lt(out2, t)

  carry := or(carry2, carry)
}

let x1 := calldataload(0)
let x2 := calldataload(32)
let y1 := calldataload(64)
let y2 := calldataload(96)

let a := 0
let b := 0
let c := 0
a, b, c := add_with_carry_384_orig(x1, x2, y1, y2)

mstore(0, a)
mstore(32, b)
mstore(64, c)

// orig: 600035604035810181811080602035019250606035830182600052806020528381108285101760405250505050
// new:  6000356020356040358201606035820183821081018260005280602052818110848310176040525050505050

}
}