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

USUBW2 (vector, 2D)

Test 1: uops

Code:

  usubw2 v0.2d, v0.2d, 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)
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000
1004203310011100010005024810001000200011000

Test 2: Latency 1->2

Code:

  usubw2 v0.2d, v0.2d, 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): 2.0033

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)
1020420033101011011000001001000003000509248101002000100062000200081010000100
1020420033101011011000001001000003000509248101002000100062000200081010000100
1020420033101011011000001001000003000509248101002000100042000200081010000100
1020420033101011011000001001000003000509248101002000100042000200081010000100
1020420033101011011000001001000003000509248101002000100042000200081010000100
1020420033101011011000001001000003000509248101002000100042000200081010000100
1020420033101011011000001001000003000509248101002000100042000200081010000100
1020420033101011011000001001000003000509248101002000100042000200081010000100
1020420033101011011000001001000003000509248101002000100042000200081010000100
1020420033101011011000001001000003000509248101002000100042000200081010000100

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0033

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)
1002420033100212110000201000070509247100202010006200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010
1002420033100212110000201000070509248100202010000200200001101000010

Test 3: Latency 1->3

Code:

  usubw2 v0.2d, v1.2d, 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): 2.0033

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)
1020420033101011011000010010000300509248101002001000620020008110000100
1020420033101011011000010010000300509248101002001000420020008110000100
1020420033101011011000010010000300509248101002001000420020008110000100
1020420033101011011000010010000300509248101002001000420020008110000100
1020420033101011011000010010000300509248101002001000420020008110000100
1020420033101011011000010010000300509248101002001000420020008110000100
1020520066101111031000810210034300509248101002001000420020008110000100
1020420033101011011000010010000300509248101002001000420020008110000100
1020420033101011011000010010000300509248101002001000420020008110000100
1020420033101011011000010010000300509248101002001000620020012110000100

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0033

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)
10024200331002121100002010000705092481002020100042020000111000010
10024200331002121100002010000705092481002020100002020000111000010
10024200331002121100002010000705092481002020100002020000111000010
10024200331002121100002010000705092481002020100002020000111000010
10024200331002121100002010000705092481002020100002020000111000010
10024200841003321100122010036705092481002020100002020000111000010
10024200331002121100002010000705092481002020100002020000111000010
10024200331002121100002010000675103121009220100832020084111000010
10024200331002121100002010000705092481002020100002020000111000010
10024200331002121100002010000705092481002020100002020000111000010

Test 4: throughput

Count: 8

Code:

  usubw2 v0.2d, v8.2d, v9.4s
  usubw2 v1.2d, v8.2d, v9.4s
  usubw2 v2.2d, v8.2d, v9.4s
  usubw2 v3.2d, v8.2d, v9.4s
  usubw2 v4.2d, v8.2d, v9.4s
  usubw2 v5.2d, v8.2d, v9.4s
  usubw2 v6.2d, v8.2d, v9.4s
  usubw2 v7.2d, v8.2d, 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): 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 simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
80204400678010710180006100800103003200448011020080014200160028180000100
80205400698014310180042100800543003200448011020080013200160030180000100
80204400448010710180006100800103003200448011020080014200160024180000100
80204400348010510180004100800083003200368010820080012200160024180000100
80204400348010510180004100800083003200368010820080012200160024180000100
80204400348010510180004100800083003200368010820080012200160024180000100
80204400348010510180004100800083003200368010820080012200160024180000100
80204400348010510180004100800083003200368010820080012200160024180000100
80204400348010510180004100800083003200368010820080012200160024180000100
80204400348010510180004100800083003200368010820080012200160024180000100

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 simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
800244016780029218000820800126832000080020208000020160000118000010
800244003480021218000020800006532000080020208000020160000118000010
800244003480021218000020800006432020880074208006320160000118000010
800244003480021218000020800006532000080020208000020160000118000010
800244003480021218000020800006532000080020208000020160000118000010
800244003480021218000020800006532000080020208000020160000118000010
800244003480021218000020800006532000080020208000020160000118000010
800244003480021218000020800006532000080020208000020160000118000010
800244003480021218000020800006532000080020208000020160000118000010
800244003480021218000020800006532000080020208000020160000118000010