Method add_ref

bitvm/src/bigint/add.rs:261–291

Add BigInt on top of the stack to a BigInt at `b` depth in the stack # Note This function consumes the BigInt on top of the stack while not consuming the referenced BigInt

(b: u32)

    /// This function consumes the BigInt on top of the stack while not consuming
    /// the referenced BigInt
    pub fn add_ref(b: u32) -> Script {
        let b_depth = b * Self::N_LIMBS;
        assert_ne!(b, 0);
        script! {
            { b_depth } OP_PICK
            OP_ADD

            // OP_DEPTH OP_1SUB OP_PICK
            { 1 << LIMB_SIZE }
            OP_SWAP

            { limb_add_create_carry() }
            OP_TOALTSTACK

            for _ in 0..Self::N_LIMBS - 2 {
                OP_ROT
                { b_depth + 2 } OP_PICK
                OP_ADD
                OP_ADD { limb_add_create_carry() } OP_TOALTSTACK
            }

            OP_NIP
            { b_depth + 1 } OP_PICK
            OP_SWAP
            { limb_add_with_carry_prevent_overflow(Self::HEAD_OFFSET) }

            for _ in 0..Self::N_LIMBS - 1 {
                OP_FROMALTSTACK
            }
        }
    }

    /// Add BigInt referenced by the integer (depth) on top of the stack to the BigInt at
    /// the top the stack below the depth