Apple Microarchitecture Research by Dougall Johnson

M1/A14 P-core (Firestorm): Overview | Base Instructions | SIMD and FP Instructions
M1/A14 E-core (Icestorm):  Overview | Base Instructions | SIMD and FP Instructions

FMADD (scalar, S)

Test 1: uops

Code:

  fmadd s0, s0, s1, s2
  movi v0.16b, 1
  movi v1.16b, 2
  movi v2.16b, 3

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 1.000

Issues: 1.000

Integer unit issues: 0.001

Load/store unit issues: 0.000

SIMD/FP unit issues: 1.000

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch simd uop (57)ldst uops in schedulers (5b)dispatch uop (78)map simd uop (7e)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)
10044033100111000100010155710001000300011000
10044033100111000100010155710001000300011000
10044033100111000100010155710001000300011000
10044033100111000100010155710001000300011000
10044033100111000100010155710001000300011000
10044033100111000100010155710001000300011000
10044033100111000100010155710001000300011000
10054066100511004103010155710001000300011000
10044033100111000100010155710001000300011000
10044033100111000100010155710001000300011000

Test 2: Latency 1->2

Code:

  fmadd s0, s0, s1, s2
  movi v0.16b, 1
  movi v1.16b, 2
  movi v2.16b, 3

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 4.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10205400661010510110004100100303001028557101002001000420030012110000100
10205400661010710310004102100303001028557101002001000420030012110000100

1000 unrolls and 10 iterations

Result (median cycles for code): 4.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
100244003310021211000020100007010285571002020100042030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010

Test 3: Latency 1->3

Code:

  fmadd s0, s1, s0, s2
  movi v0.16b, 1
  movi v1.16b, 2
  movi v2.16b, 3

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 4.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10205400661010510110004100100303001028557101002001000420030246110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420230126210000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100

1000 unrolls and 10 iterations

Result (median cycles for code): 4.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
100244003310021211000020100007010285571002020100042030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030000111000010
100244003310021211000020100007010285571002020100002030132111000010
100244003310021211000020100007010289041005020100442030000111000010
100244003310021211000020100007010285571002020100002030000111000010

Test 4: Latency 1->4

Code:

  fmadd s0, s1, s2, s0
  movi v0.16b, 1
  movi v1.16b, 2
  movi v2.16b, 3

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 4.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
10204400331010110110000100100003001028557101002001000620230138210000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100
10204400331010110110000100100003001028557101002001000420030012110000100

1000 unrolls and 10 iterations

Result (median cycles for code): 4.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map ldst uop inputs (80)map simd uop inputs (81)? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)
10024400331002121100002010000701028557100202010004200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010
10024400331002121100002010000701028557100202010000200300001101000010

Test 5: throughput

Count: 8

Code:

  fmadd s0, s8, s9, s10
  fmadd s1, s8, s9, s10
  fmadd s2, s8, s9, s10
  fmadd s3, s8, s9, s10
  fmadd s4, s8, s9, s10
  fmadd s5, s8, s9, s10
  fmadd s6, s8, s9, s10
  fmadd s7, s8, s9, s10
  movi v8.16b, 9
  movi v9.16b, 10
  movi v10.16b, 11

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.5004

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)dispatch ldst uop (58)int uops in schedulers (59)simd uops in schedulers (5a)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map ldst uop (7d)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
80204400818010710180006100800100300032003680108200080012200240036180000100
80204400368010510180004100800080300032003680108200080012200240036180000100
80204400368010510180004100800080300032003680108200080012200240036180000100
80204400368010510180004100800080300032003680108200080012200240036180000100
80205400728014310180042100800540300032003680108200080012200240036180000100
80204400368010510180004100800080300032003680108200080012200240036180000100
80204400368010510180004100800080300032003680108200080012200240036180000100
80205400728014510180044100800560300032003680108200080012200240036180000100
80204400368010510180004100800080300032003680108200080012200240036180000100
80204400368010510180004100800080300032003680108200080012200240195180000100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.5004

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)int uops in schedulers (59)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map ldst uop inputs (80)map simd uop inputs (81)? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)
80024401218002721800062080010703200448003020800162002400001108000010
80024400368002121800002080000703200008002020800002002400001108000010
80025400738006921800482080060703200008002020800002002400001108000010
80024400368002121800002080000703200008002020800002002400001108000010
80024400368002121800002080000703200008002020800002002400001108000010
80024400368002121800002080000703200008002020800002002400001108000010
80024400718002721800062080010703200008002020800002002400001108000010
80024400368002121800002080000703200008002020800002002400001108000010
80024400368002121800002080000703200008002020800002002400001108000010
80024400368002121800002080000703200008002020800002002400001108000010