/* Round 3 */
                a = HH (a, b, c, d, x[5], S31, 0xfffa3942L); /* 33 */
                d = HH (d, a, b, c, x[8], S32, 0x8771f681L); /* 34 */
                c = HH (c, d, a, b, x[11], S33, 0x6d9d6122L); /* 35 */
                b = HH (b, c, d, a, x[14], S34, 0xfde5380cL); /* 36 */
                a = HH (a, b, c, d, x[1], S31, 0xa4beea44L); /* 37 */
                d = HH (d, a, b, c, x[4], S32, 0x4bdecfa9L); /* 38 */
                c = HH (c, d, a, b, x[7], S33, 0xf6bb4b60L); /* 39 */
                b = HH (b, c, d, a, x[10], S34, 0xbebfbc70L); /* 40 */
                a = HH (a, b, c, d, x[13], S31, 0x289b7ec6L); /* 41 */
                d = HH (d, a, b, c, x[0], S32, 0xeaa127faL); /* 42 */
                c = HH (c, d, a, b, x[3], S33, 0xd4ef3085L); /* 43 */
                b = HH (b, c, d, a, x[6], S34, 0x4881d05L); /* 44 */
                a = HH (a, b, c, d, x[9], S31, 0xd9d4d039L); /* 45 */
                d = HH (d, a, b, c, x[12], S32, 0xe6db99e5L); /* 46 */
                c = HH (c, d, a, b, x[15], S33, 0x1fa27cf8L); /* 47 */
                b = HH (b, c, d, a, x[2], S34, 0xc4ac5665L); /* 48 */