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

SQSHLU (vector, 8H)

Test 1: uops

Code:

  sqshlu v0.8h, v0.8h, #3
  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)
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000
1004203310011100010005024810001000100011000

Test 2: Latency 1->2

Code:

  sqshlu v0.8h, v0.8h, #3
  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)
1020420033101011011000010010000300509248101002001000620010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100
1020420033101011011000010010000300509248101002001000420010004110000100

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)
10024200331002121100002010000705092481002020100042010004111000010
10024200331002121100002010000705092481002020100002010000111000010
10024200331002121100002010000705092481002020100002010000111000010
10024200331002121100002010000705092481002020100002010000111000010
10024200331002121100002010000705092481002020100002010000111000010
10024200331002121100002010000705092481002020100002010000111000010
10024200331002121100002010000705092481002020100002010000111000010
10024200331002121100002010000705092481002020100002010000111000010
10024200331002121100002010000705092481002020100002010000111000010
10024200331002121100002010000705092481002020100002010000111000010

Test 3: throughput

Count: 8

Code:

  sqshlu v0.8h, v8.8h, #3
  sqshlu v1.8h, v8.8h, #3
  sqshlu v2.8h, v8.8h, #3
  sqshlu v3.8h, v8.8h, #3
  sqshlu v4.8h, v8.8h, #3
  sqshlu v5.8h, v8.8h, #3
  sqshlu v6.8h, v8.8h, #3
  sqshlu v7.8h, v8.8h, #3
  movi v8.16b, 9

(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)
8020441017807211018062010080624300322332806822008058520080777180000100
8020441204808721018077110080775307322892808242028072620080683180000100
8020441127808181018071710080721314323132808862048078620280681280000100
8020441204808611038075810280762300323100808742008077820680727480000100
8020441064807751018067410080678307322688807732028067520280729280000100
8020441133808151018071410080718300322880808192008072320080718180000100
8020441207808761058077110480775314323080808732048077320080730180000100
8020440970807281018062710080631300320036801082008001220080012180000100
8020440034801051018000410080008300320036801082008001220080012180000100
8020440034801051018000410080008300320036801082008001220080012180000100

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)
80024401228002921800082080012703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010
80024400348002121800002080000703200008002020800002080000118000010