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

FCVTNU (vector, 4H)

Test 1: uops

Code:

  fcvtnu v0.4h, v0.4h
  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)03l1i tlb fill (04)181e1f3a3f4e51schedule uop (52)schedule simd uop (54)dispatch simd uop (57)ldst uops in schedulers (5b)696d6emap 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 miss (a1)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
100430372400132028325472510001000100039816030183037303724143289510001000100030373037111001100000377516442629100030383038303830383086
1004303724100026225472510001000100039816030183037303724143289510001000100030373037111001100000077416442695100030383038303830383038
1004303723100026225472510001000100039816030183037303724143289510001000100030373037111001100001077416442629100030383038303830383038
1004303724103026225472510001000100039816030183037303724143289510001000100030373037111001100001077416442629100030383038303830383038
10043037241042028325472510001000100039816030183121303724143289510001000100030373037111001100000077416442629100030383038303830383038
1004303724103026225472510001000100039816030183037303724143289510001000100030373037111001100000377416442629100030383038303830383038
100430372410195026225472510001000100039816030183037303724143289510001000100030373037111001100000077416442629100030383038303830383038
1004303723103026225472510001000100039816030183037303724143289510001000100030373037111001100000077416442629100030383038303830383038
10043037231000210425472510001000100039816030183037303724143289510001000100030373037111001100000077416442629100030383038303830383038
1004303723109028325472510001000100039816030183037303724143289510001000100030373037111001100005077416442629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtnu v0.4h, v0.4h
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)0318191e3f4e51schedule 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 cache writeback (a8)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10204300372320006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100071011611296330100001003003830038300383003830038
10204300372322006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100074111611296330100001003003830038300383003830038
10204300372330006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100071011611296330100001003003830038300383003830038
10204300372330006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100071011611296330100001003003830038300383003830038
10204300372330006129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100071011611296330100001003003830038300383003830038
10204300372320006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100171011611296330100001003003830038300383003830038
10204300372330006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100071011611296330100001003003830038300383003830038
10204300372320006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100071011611296330100001003003830038300383003830038
10204300372320006129547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100071011611296330100001003003830038300383003830038
10204300372320006129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100071011611296330100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)0318191e3f4e51schedule 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 cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002430037224001861295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640416552962910000103003830038300383003830038
100243003722500061295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000661516562962910000103003830038300383003830038
100243003722500061295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000640616662962910000103003830038300383003830038
100243003722500061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640516552962910000103003830038300383003830038
100243003722500061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001003640616662962910000103003830038300383003830038
1002430037225001861295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640516552962910000103003830086300863003830038
1002430120225406145295382510020101000011100007142771601300183003730037282863287671001020100002010000300373003711100211091010100001000640516652962910000103003830038300383003830038
100243003722500061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001033640516552962910000103003830038300383003830038
100243003722500061295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001010640616662962910000103003830038300383003830038
100243003722500082295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000730516662962910000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtnu v0.4h, v8.4h
  fcvtnu v1.4h, v8.4h
  fcvtnu v2.4h, v8.4h
  fcvtnu v3.4h, v8.4h
  fcvtnu v4.4h, v8.4h
  fcvtnu v5.4h, v8.4h
  fcvtnu v6.4h, v8.4h
  fcvtnu v7.4h, v8.4h
  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)0318191e1f3a3f51schedule 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)60696b6d6emap 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)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)dde0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8020420058156003000512580108100800081008002050064013212002002003920039997769990801202008003220080032200392003911802011009910010080000100201145118223120036800001002004020040200402004020040
802042003915500000302580108100800081008002050064013202002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040
802042003915500000302580108100800081008002050064013212002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040
802042003915500000726080310100800081008002050064013212002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040
802042003915600000302580108100800081008002050064013202002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040
802042003915500000302580108100800081008002050064013212002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040
802042003915500000302580108100800081008002050064013212002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040
802042003915600300302580108100800081008002050064013212002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040
802042003915600000302580108100800081008002050064013212002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040
8020420039156000006952580108100800081008002050064013212002002003920039997769990801202008003220080032200392003911802011009910010080000100001115118016020036800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03mmu table walk instruction (07)1e3f51schedule 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)5f60696b6d6emap stall dispatch (70)simd prf full (72)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)cfd5map dispatch bubble (d6)ddfetch restart (de)e0ec? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200501550040258001010800001080000506400000120020320039200399996031001980010208000020800002003920039118002110910108000010050203162220036080000102004020040200402004020040
800242003915501240258001010800001080000506400000120020020039200399996031001980010208000020800002003920039118002110910108000010050202162220036080000102004020040200402004020040
80024200391550040258001010800001080000506400000120020020039200399996031001980010208000020800002003920039118002110910108000010050202162220036080000102004020040200402004020040
80024200391550040258001010800001080000506400000120020020039200399996031001980010208000020800002003920039118002110910108000010050202162220036080000102004020040200402004020040
80024200391550040258001010800001080000506400000120020020039200399996031001980010208000020800002003920039118002110910108000010150202162220036080000102004020040200402004020040
80024200391550040258001010800001080000506400000120020020039200399996031001980010208000020800002003920039118002110910108000010050202162220036080000102004020040200402004020040
80024200391550040258001010800001080000506400000120020020039200399996031001980010208000020800002003920039118002110910108000010050202162220036080000102004020040200402004020040
800242003915503961258001010800001080000506400000120020020039200399996031001980010208010520800002003920039118002110910108000010050202162220036080000102004020040200402004020040
80024200391550040258001010800001080000506400000120020020039200399996031001980010208000020800002003920039118002110910108000010050202162220036080000102004020040200402004020040
80024200391550082258001010800001080000506400000120020020039200399996031001980010208000020800002003920039118002110910108000010050202162220036080000102004020040200402004020040