* Round 1 */
STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7)
STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12..., SET(10), 0xffff5bb1, 17)
STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22)
STEP(F, a, b, c, d, SET(12..., c, GET(2), 0xfcefa3f8, 9)
STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14)
STEP(G, b, c, d, a, GET(12... a, GET(6), 0x04881d05, 23)
STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4)
STEP(H2, d, a, b, c, GET(12...b, GET(14), 0xab9423a7, 15)
STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21)
STEP(I, a, b, c, d, GET(12