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

CNT (8B)

Test 1: uops

Code:

  cnt v0.8b, v0.8b
  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: 0.000

Load/store unit issues: 0.000

SIMD/FP unit issues: 1.000

retire uop (01)cycle (02)03mmu table walk instruction (07)mmu table walk data (08)l2 tlb miss instruction (0a)l2 tlb miss data (0b)18191e1f3a3f4e51schedule uop (52)schedule simd uop (54)dispatch simd uop (57)ldst uops in schedulers (5b)60696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map simd uop (7e)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst simd alu (9a)l1d tlb access (a0)l1d tlb miss (a1)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
10042037150000000006116862510001000100026452112018203720371571318951000100010002037203711100110000000000073216221786100020382038203820382038
10042037150000000006116862510001000100026452112018203720371571318951000100010002037203711100110000000000073216221786100020382038203820382038
100420371500000000061168625100010001000264521120182037203715713189510001000100020372037111001100000000018073216221786100020382038203820382038
10042037150000000006116862510001000100026452112018203720371571318951000100010002037203711100110000000000073216221786100020382038203820382038
10042037150000000006116862510001000100026452112018203720371571318951000100010002037203711100110000000000073216221786100020382038203820382038
10042037150000000006116862510001000100026452112018203720371571318951000100010002037203711100110000000000073216221786100020382038203820382038
10042037150000000006116862510001000100026452112018203720371571318951000100010002037203711100110000000000073216221786100020382038203820382038
10042037150000000006116862510001000100026452112018203720371571318951000100010002037203711100110000000009073216221786100020382038203820382038
10042037150000000006116862510001000100026452112018203720371571318951000100010002037203711100110000020000073216221786100020382038203820382038
1004203715000000059806116862510001000100026452112018203720371571318951000100010002037203711100110000000000073216221786100020382038203820382038

Test 2: Latency 1->2

Code:

  cnt v0.8b, v0.8b
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 2.0037

retire uop (01)cycle (02)03l2 tlb miss instruction (0a)18191e3f4e51schedule 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)696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)inst simd alu (9a)9fl1d cache writeback (a8)acbranch cond mispred nonspec (c5)cdcfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
10204200371500000611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
10204200371500000611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
10204200371500000611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
10204200371500000611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
10204200371510000611968625101001001000010010000500284752120018200372003718421318745101002001000020010665200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
10204200371500130611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
10204200371500000611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
102042003715000033611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
10204200371500000611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038
10204200371500000611968625101001001000010010000500284752120018200372003718421318745101002001000020010000200372003711102011009910010010000100000071001161119791100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire uop (01)cycle (02)03mmu table walk data (08)09l2 tlb miss data (0b)18191e1f3a3f4e51schedule 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)60696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)inst simd alu (9a)9fl1d tlb access (a0)l1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10024200371500000000061196862510010101000010100005028475211200182003720037184433187671001020103302010000200372003711100211091010100001000000006404165519786010000102003820038200382003820038
10024200371500100000061196862510010101000010100005028475211200182003720037184433187671001020100002010000200372003711100211091010100001000000006406166519786010000102003820038200382003820038
10024200371500000000061196862510010101000010100005028475211200182003720037184433187671001020100002010000200372003711100211091010100001000000006406166519786010000102003820038200382003820038
10024200371500000000061196862510010101000010100005028475210200542003720037184433187671001020100002010000200372003711100211091010100001000010006406166519786010000102003820038200382003820038
10024200371500000000061196862510010101000010100005028475211200182003720037184433187671001020100002010000200372003711100211091010100001000000006405166519786010000102003820038200382003820038
100242003715000000000251196862510010101000010100005028475211200182003720037184433187671001020100002210000200372003711100211091010100001000000006406166619786010000102003820038200382003820038
100242003715000000000103196862510010101000010100005028475211200182003720037184433187671001020100002010000200372003711100211091010100001000000006405164519786010000102008520086200382013320038
10024200371500010100061196862510010101000010100005028475211200182008420037184433187851031620100002010000200842003711100211091010100001000000006404166619786010000102003820038200382003820038
10024200371500000000061196862510010101000010100005028475211200182003720037184433187671001020100002010000200372003711100211091010100001000000006406165619786010000102003820038200382003820038
10024200371500000000061196862510010101000010100005028475211200182003720037184433187671001020100002010000200372003711100211091010100001000000006406166519786010000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  cnt v0.8b, v8.8b
  cnt v1.8b, v8.8b
  cnt v2.8b, v8.8b
  cnt v3.8b, v8.8b
  cnt v4.8b, v8.8b
  cnt v5.8b, v8.8b
  cnt v6.8b, v8.8b
  cnt v7.8b, v8.8b
  movi v8.16b, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.2505

retire uop (01)cycle (02)03mmu table walk data (08)l2 tlb miss data (0b)181e1f3f51schedule 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)696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)inst simd alu (9a)9fl1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8020420057150000420409258010810080008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001000000011151181161120035800001002003920039200392003920039
802042003815000024029258010810080008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001000004611151181161120035800001002003920039200392003920039
80204200381500003029258010810080008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001000000011151181161120035800001002003920039200392003920039
802042003815000118029258010810080008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001000000011151181161120035800001002003920039200392003920039
80204200381500009029258010810280008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001002000011151181161120035800001002003920039200392003920039
802042003815000069029258010810080008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001000000011151181161120035800001002003920039200392003920039
802042003815000090292580108100800081008002050064013220019200382003899771299898012020080032200800322003820038118020110099100100800001000000011151181161120035800001002003920039200392003920039
80204200381500000029258010810080008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001000000011151181161120035800001002003920039200392003920039
80204200381500000029258010810080008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001000000011151181161120035800001002003920039200392003920039
80204200381500000029258010810080008100800205006401322001920038200389977699898012020080032200800322003820038118020110099100100800001000000011151181161120035800001002003920039200392003920039

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.2505

retire uop (01)cycle (02)03mmu table walk data (08)l2 tlb miss data (0b)18191e1f3a3f51schedule 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)5f60696d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)inst simd alu (9a)9fl1d tlb access (a0)l1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acc2cfd2d5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200391500000000392580010108000010800005064076401200192003820038999631001880010208000020800002003820038118002110910108000010000000050200616432003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000001200192003820038999631001880010208000020800002003820038118002110910108000010000000050200516532003580000102003920039200392003920039
8002420038150000054000392580010108000010800005064000001200192003820038999631001880010208000020800002003820038118002110910108000010000000050200316762003580000102003920039200392003920039
800242003815000001200392580010108000010800005064000001200192003820038999631001880010208000020800002003820038118002110910108000010000100050200916642003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000001200192003820038999631001880010208000020800002003820038118002110910108000010000000050200416672003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000001200192003820038999631001880010208000020800002003820038118002110910108000010000000050200416432003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000001200192003820038999631001880010208000020800002003820038118002110910108000010000000050200316642003580000102003920039200392003920039
800242003815000000007042580010108000010800005064000011200192003820038999631001880010208000020800002003820038118002110910108000010000000050200416642003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000001200192003820038999631001880010208000020800002003820038118002110910108000010000000050200416342003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000001200192003820038999631001880010208000020800002003820038118002110910108000010000000050200316342003580000102003920039200392003920039