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

FCVTMS (scalar, D to X)

Test 1: uops

Code:

  fcvtms x0, d0
  mov x0, 1
  mov x1, 2

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 2.000

Issues: 3.000

Integer unit issues: 1.000

Load/store unit issues: 0.000

SIMD/FP unit issues: 2.000

retire uop (01)cycle (02)031e3f51schedule uop (52)schedule int uop (53)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 int alu (97)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
20045414043253000100020002000180000522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180000522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180000522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180000522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180000522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180000522541541248327420002000200054154111100110007331633538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110007331633538100010001000542542542542542

Test 2: Latency 1->2 roundtrip

Code:

  fcvtms x0, d0
  fmov d0, x0
  mov x0, 1
  mov x1, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 13.0038

retire uop (01)cycle (02)03l1i tlb fill (04)181e1f3f4f51schedule 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)60696d6emap stall dispatch (70)map rewind (75)map stall (76)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)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)a9acbranch mispred nonspec (cb)cdcfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
302041300389741000130023119417254010010100200001000010020000100005006214979148010341130013130038130038125476312629330100200100002000020010000200001300381300381120201100991001010010000100001000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740000130023119417254010010100200001000010020000100005006214979148010341130013130038130038125476312629930100200100002000020010000200001300381300381120201100991001010010000100001000000000131012162212952510000100001000010100130039130039130102130043130039
302041300429740000130023119417254010010100200001000010020000100005006214979148010341130013130038130038125476312628730100200100002000020010000200001300381300381120201100991001010010000100001000000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400001300231194172540100101002000010000100200001000050062149791480103401300131300381300381254763126294301002001000020000200100002012913003813003811202011009910010100100001002010000021881000131012162212952510000100001000010100130039130622130597130039130083
30204130038974030013002311941725401001010020000100001002000010000500621497914801034113001313003813003812547631263023010020010000200002001000020000130038130038112020110099100101001000010000100000020100131012163212952510000100001000010100130039130039130039130039130039
302041300389740000130023119417254010010100200041000010020000100005006214979148010341130013130038130038125476312625530100202100002000020010000200001300381300381120201100991001010010000100001000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740000130023119417254010010100200001000010020000100005006214979148010340130013130038130038125476312626330100200100002000020010000200001300381300381120201100991001010010000100001000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740000130023119417254010010100200001000010020000100005006214979148010341130013130038130038125476312629230100200100002000020010000200001300381300381120201100991001010010000100001000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740000130023119417254010010100200001000010020000100005006214979148010340130013130038130038125476312627630100200100002000020010000200001300381300381120201100991001010010000100001000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740000130058119417254010010100200001000110020000100005006214979148010341130013130038130038125476312627330100200100002000020010000200001300381300381120201100991001010010000100001000000000131012162212955710000100001000010100130039130039130039130039130039

1000 unrolls and 10 iterations

Result (median cycles for code): 13.0038

retire uop (01)cycle (02)03mmu table walk instruction (07)mmu table walk data (08)l2 tlb miss instruction (0a)18191e1f3f4f51schedule 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)60696b6d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)7amap 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)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)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
300241300381008000000013002811941725400101001020000100001020000100005062149791480002501300133130038130038125498312626830010020100002000020100002000013003813003811200211091010010100001001000000012702161112952510000100001000010010130039130039130039130039130039
300241300381008000000013002311941725400101001020000100001020000100005062149791480002501300130130038130038125498312626830010020100002000020100002000013003813003811200211091010010100001001000000012701161112952610000100001000010010130039130039130039130039130039
300241300381007000000013002311941725400101001020000100001020000100005062149791480002501300130130038130038125498312626830010020100002000020100002000013003813003811200211091010010100001001000000012701161112952510000100001000010010130039130039130039130039130039
300241300381008000000013002311941825400101001020000100001020000100005062149791480002511300130130038130038125498312626830010020100002000020104312097513073813080991200211091010010100001001000510012701161112952510000100001000010010130039130039130039130039130039
300241300381007000000013002311941725400101001020000100001020000100005062149791480002511300130130038130038125498312626830010020100002000020100002000013003813003811200211091010010100001001000000012701161112952510000100001000010010130039130039130039130039130039
300241300381008000000013002311941725400101001020000100001020000100005062149791480002501300130130038130038125498312626830010020100002000020100002000013003813003811200211091010010100001001000000012701161112952510000100001000010010130039130039130039130039130039
300241300381008000000013002311941725400101001020000100001020000100005062149791480002511300130130038130038125498312626830010020100002000020100002000013003813003811200211091010010100001001000000012701161112952510000100001000010010130039130039130039130039130039
3002413003810080000030013002311941725400101001020000100001020000100005062149791480002501300130130038130038125512312626830010020100002000020100002000013003813003811200211091010010100001001000000012701161112952510000100001000010010130039130039130039130039130039
300241300381008000000013002411941725400101001420000100001020000100005062149791480002511300130130038130038125498312626830010020100002000020100002000013003813003811200211091010010100001001000000012701161112952510000100001000010010130039130075130085130039130039
30025130081974000000013002311941725400101001020000100001020000100005062149791480002511300130130038130038125498312626830010020100002000020100002000013003813003811200211091010010100001001000001012701161112952510000100001000010010130039130039130039130039130040

Test 3: throughput

Count: 8

Code:

  fcvtms x0, d8
  fcvtms x1, d8
  fcvtms x2, d8
  fcvtms x3, d8
  fcvtms x4, d8
  fcvtms x5, d8
  fcvtms x6, d8
  fcvtms x7, d8
  mov x8, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.5005

retire uop (01)cycle (02)03l2 tlb miss data (0b)181e3f51schedule 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)9fl1d cache writeback (a8)acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
16020440062300000322524010480100160004100160020500144013204002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042
160204400413000005325240104801001600041001600205001440132140022400414004119977151999216033620016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042
160204400413000006022524010480100160004100160020500144013204002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042
160204400412990005982524010480100160004100160020500144013214002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511711600400388000080000801004004240042400424004240042
16020440041300000322524010480100160004100160020500144013204002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042
16020440041300000322524010480100160004100160020500144013204002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042
16020440041300000322524010480100160004100160020500144013204002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042
16020440041300000322524035080100160004100160020500144013204002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042
16020440041300000322524010480100160004100160020500144013214002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042
16020440041300000322524010480100160004100160020500144013214002240041400411997761999216012020016003220016003240041400411180201100991008010010000111511701600400388000080000801004004240042400424004240042

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.5005

retire uop (01)cycle (02)03mmu table walk instruction (07)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)5f60696b6d6emap 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)9fl1d tlb access (a0)l1d cache writeback (a8)a9acc2branch mispred nonspec (cb)cfd0d5map dispatch bubble (d6)dbddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
160024400553000000013012524001080010160000101600005014400000040022040041400411999632002116001020160000201600004004140041118002110910800101000000050200216055400388000080000800104004240042400424004240042
16002440041300000000422524001080010160000101600005014400001040022040041400411999632002116001020160000201600004004140041118002110910800101000000050200316034400388000080000800104004240042400424004240042
160024400413000000002352524001080010160000101600005014400000040022040041400411999632002116001020160000201600004004140041118002110910800101000000050200416043400388000080000800104004240042400424004240042
160024400413000000001952524001080010160000101600005014400000040022040041400411999632002116001020160000201600004004140041118002110910800101000000050200316044400388000080000800104004240042400424004240042
160024400413000000001282524001080010160180101600005014400000040022040041400411999632002116001020160000201600004004140041118002210910800101000000050200416043400388029280000800104004240042400424004240042
160024400413000000009202524001080010160000101600005014400000040022040041400411999632002116001020160000201600004004140041118002110910800101000000050200316044400388000080000800104004240042400424004240042
160024400413000000001322524001080010160000101600005014400000040022040041400411999632002116001020160000201600004004140041118002110910800101000000050200416044400388000080000800104004240042400424004240042
160024400413000009001072524001080010160000101600005014400000040022040041400411999632002116001020160000201600004004140041118002110910800101000000050200516035400388000080000800104004240042400424004240042
160024400413000000001952524001080010160000101600005014400000040022040041400411999632002116001020160000201600004004140041118002110910800101000030050200416044400388000080000800104004240042400424004240042
160024400412990000003212524001080010160000101600005014400000040022040041400411999632002116001020160000201600004004140041118002110910800101000000050200316033400388000080000800104004240042400424004240042