   T1 = ADD5(A, RR(F, 6) ^ RR(F, 11) ^ RR(F, 25), (F & G) ^ (~F & H), 0xC67178F2, Wf);
        A = ADD3(T1, RR(B, 2) ^ RR(B, 13) ^ RR(B, 22), (B & C) ^ (C & D) ^ (B & D));
        E = ADD(E, T1);

        this.current[0] += A;
        this.current[1] += B;
        this.current[2] += C;
        this.current[3] += D;
        this.current[4] += E;
        this.current[5] += F;
        this.current[6] += G;
        this.current[7] += H;
        this.currentLen += 64;
    };

    sha256Engine.prototype.doPadding