md5_round1
md5_round1(&A, B, C, D, X0, 0xd76aa478L, 7);
md5_round1(&D, A, B, C, X1, 0xe8c7b756L, 12);
md5_round1(&C, D, A, B, X2, 0x242070dbL, 17);
md5_round1(&B, C, D, A, X3, 0xc1bdceeeL, 22);
md5_round1(&A, B, C, D, X4, 0xf57c0fafL, 7);
md5_round1(&D, A, B, C, X5, 0x4787c62aL, 12);
md5_round1(&C, D, A, B, X6, 0xa8304613L, 17);
md5_round1(&B, C, D, A, X7, 0xfd469501L, 22);
md5_round1(&A, B, C, D, X8, 0x698098d8L, 7);
md5_round1(&D, A, B, C, X9, 0x8b44f7afL, 12);
md5_round1(&C, D, A, B, X10, 0xffff5bb1L, 17);
md5_round1(&B, C, D, A, X11, 0x895cd7beL, 22);
md5_round1(&A, B, C, D, X12, 0x6b901122L, 7);
md5_round1(&D, A, B, C, X13, 0xfd987193L, 12);
md5_round1(&C, D, A, B, X14, 0xa679438eL, 17);
md5_round1(&B, C, D, A, X15, 0x49b40821L, 22);