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

FDIV (vector, 4S)

Test 1: uops

Code:

  fdiv v0.4s, v0.4s, v1.4s
  movi v0.16b, 1
  movi v1.16b, 2

(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)
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000
10049033100111000100011516010001000200011000

Test 2: Latency 1->2

Code:

  fdiv v0.4s, v0.4s, v1.4s
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 9.0033

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)
1020490033101011011000010010000300115916010100200100062000200521010000100
1020490033101011011000010010000300115916010100200100062000200581010000100
1020490033101011011000010010000300115916010100200100042000200081010000100
1020490033101011011000010010000300115916010100200100042000200081010000100
1020490033101011011000010010000300115916010100200100042000200081010000100
1020490033101011011000010010000300115916010100200100042000200081010000100
1020490033101011011000010010000300115916010100200100042000200081010000100
1020490080101041011000310010016300115916010100200100042000200561010000100
1020490033101011011000010010000300115916010100200100042000200081010000100
1020490033101011011000010010000300115916010100200100042000200081010000100

1000 unrolls and 10 iterations

Result (median cycles for code): 9.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)schedule ldst uop (55)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)
100249003310021211000002010000701159160100202010006200200001101000010
100249003310021211000002010000701159160100202010000200200001101000010
100249003310021211000002010000701159160100202010000200200001101000010
100249003310021211000002010000701159160100202010000200200001101000010
100249003310021211000002010000701159160100202010000200200001101000010
100249003310021211000002010000701159160100202010000200200001101000010
100249003310021211000002010000701159160100202010000200200001101000010
100249003310021211000002010000701159160100202010000200200001101000010
2341601173927215272110820209578349510935921003701159160100202010000200200001101000010
100249003310021211000002010000701159160100202010000200200001101000010

Test 3: Latency 1->3

Code:

  fdiv v0.4s, v1.4s, v0.4s
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 9.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)schedule ldst uop (55)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 ldst uop inputs (80)map simd uop inputs (81)? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)
10204900331010110110000010010000030001159160101002000100062000200121010000100
10205900661010310110002010010015030001159160101002000100062000200081010000100
10204900331010110110000010010000030001159160101002000100042000200081010000100
10205900661010310110002010010015030001159160101002000100062000200121010000100
10204900331010110110000010010000030001159160101002000100042000200081010000100
10204900331010110110000010010000030001159160101002000100042000200081010000100
10204900331010110110000010010000030001159160101002000100042000200081010000100
10204900331010110110000010010000030001159160101002000100042000200081010000100
10204900331010110110000010010000030001159160101002000100042000200081010000100
10204900331010110110000010010000030001159160101002000100042000200081010000100

1000 unrolls and 10 iterations

Result (median cycles for code): 9.0033

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)
100249003310021211000020100007011591601002020100002020000111000010
100249003310021211000020100007011591601002020100002020000111000010
100249003310021211000020100007011591601002020100002020000111000010
100249003310021211000020100007011591601002020100002020000111000010
100259006610023211000220100157011591601002020100002020000111000010
100249003310021211000020100007011591601002020100002020000111000010
100249003310021211000020100007011591601002020100002020000111000010
100249003310021211000020100007011591601002020100002020000111000010
100249003310021211000020100007011591601002020100002020000111000010
100249003310021211000020100007011591601002020100002020000111000010

Test 4: throughput

Count: 8

Code:

  fdiv v0.4s, v8.4s, v9.4s
  fdiv v1.4s, v8.4s, v9.4s
  fdiv v2.4s, v8.4s, v9.4s
  fdiv v3.4s, v8.4s, v9.4s
  fdiv v4.4s, v8.4s, v9.4s
  fdiv v5.4s, v8.4s, v9.4s
  fdiv v6.4s, v8.4s, v9.4s
  fdiv v7.4s, v8.4s, v9.4s
  movi v8.16b, 9
  movi v9.16b, 10

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 2.0005

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)
8020516008080113101800121008002430019997698010020080006200160012180000100
8020516008080113101800121008002430019997698010020080006200160008180000100
8020416004080101101800001008000030019997698010020080004200160008180000100
8020516008080113101800121008002430020010498020420080130200160012180000100
8020416004080101101800001008000030019997698010020080006200160008180000100
8020416004080101101800001008000030019997698010020080004200160008180000100
8020516008080113101800121008002430019997698010020080004200160008180000100
8020416004080101101800001008000030019997698010020080004200160008180000100
8020416004080101101800001008000030019997698010020080004200160008180000100
8020416004080101101800001008000030019997698010020080004200160078180000100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 2.0005

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)
80024160040800212180000208000070199976980020208000420160000118000010
80024160040800212180000208000070199976980020208000020160000118000010
80024160040800212180000208000070199976980020208000020160072118000010
80024160040800212180000208000070199976980020208000020160000118000010
80024160040800212180000208000070199976980020208000020160000118000010
80024160040800212180000208000070199976980020208000020160000118000010
80024160040800212180000208000068199999480044208004020160000118000010
80024160040800212180000208000070199976980020208000020160000118000010
80024160040800212180000208000070199976980020208000020160000118000010
80024160040800212180000208000070199976980020208000020160000118000010