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

FCVTZU (scalar, integer, D to W)

Test 1: uops

Code:

  fcvtzu w0, 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)6061696d6emap 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)l1d cache writeback (a8)acc2cfd0d2d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
20045414043253000100020002000180001052254154124832742000200020005415411110011000000730011611538100010001000542542542542542
20045414043253000100020002000180000052254154124832742000200020005415411110011000000730011611538100010001000542542542542542
20045414043253000100020002000180000052254154124832742000200020005415411110011000000730011611538100010001000542542542542542
20045414043253000100020002000180001052254154124832742000200020005415411110011000000730011611538100010001000542542542542542
200454140432530001000200020001800010522541541248327420002000200054154111100110000014730011611538100010001000542542542542542
20045414043253000100020002000180001052254154124832742000200020005415411110011000000730011611538100010001000542542542542542
20045414043253000100020002000180001052254154124832742000200020005415411110011000000730011611538100010001000542542542542542
20045414043253000100020002000180001052254154124832742000200020005415411110011000000730011611538100010001000542542542542542
20045414043253000100020002000180001052254154124832742000200020005415411110011000200730011611538100010001000542542542542542
20045414043253000100020002000180001052254154124832742000200020005415411110011000000730011611538100010001000542542542542542

Test 2: Latency 1->2 roundtrip

Code:

  fcvtzu w0, 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)03mmu table walk data (08)09l2 tlb miss data (0b)18191e1f3a3f4f51schedule 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)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 miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)cdcfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
30204130038973000000001300231194192540100101002000010000100200001000050062149791480103401300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
30204130038974000000001300231194172540100101002000010000100200001000050062149791480103401300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510015100001000010100130039130039130039130039130039
30204130038974000000001300231194172540100101002000010000100200001000050062149791480103401300130130038130038125476312624630100200100002000020010000200001300441300412120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
30204130038974000009001300231194172540100101002000010000100200001000050062149791480103401300130130068130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
30204130038974000000001300231194172540100101002000010000100200001000050062149791480103401300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740000000013002311941725401001010020000100001002000010000500621497914801034013001301300381300381254763126246301002001000020000200100002000013003813003811202011009910010100100001000100016200000131012162212952510000100001000010100130039130039130039130039130039
30204130038974000000001300231194172540100101002000010000100200001000050062149791480103401300130130038130038125479312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
30204130038974000000001300231194172540100101002000010000100200001000050062149791480103401300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130040
30204130038974000000001300231194172540100101002000010000100200001000050062149791480103401300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130042130368130042130043130039
30204130038977000000001300231194172540100101002000010000100200001019650062149791480103401300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000003001131012162212952710000100001000010100130041130039130039130039130039

1000 unrolls and 10 iterations

Result (median cycles for code): 13.0038

retire uop (01)cycle (02)03mmu 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)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 cond mispred nonspec (c5)cfd5map dispatch bubble (d6)d9ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
30024130038974000055201300231194172540010100102000010000102011610000506214979148036540130013130038130038125498312626830010201000020000201006220000130066130038112002110910100101000010001000054000127021602212952510000100001000010010130039130039130039130039130039
30024130038974000000130023119417254001010010200001000010200001000050621497914800025013001313003813003812549831262733001020100002000020100002000013003813003811200211091010010100001000100000000127021602212952510000100001000010010130042130039130039130039130039
300241300389740000540130023119417254001010010200001000210200001000050621497914800025013001313003813003812549831262733001020100002000020100002000013003813003811200211091010010100001000100000000127021602212952510000100001000010010130039130039130039130039130039
300241300389730000930130023119417254001010010200001000010200001000050621497914800025113001313003813003812549831262683001020100002000020100002000013003813003811200211091010010100001000100001000127021602212952510000100001000010010130039130039130039130039130039
300241300389740000420130023119417254001010010200001000010200001000050621497914800025013001313003813003812549831262683001020100002000020100002000013003813003811200211091010010100001000100026000127021602212952510000100001000010010130039130039130039130039130039
30024130038974000000130023119417254001010010200001000010200001000050621497914800025013001313003813003812549831262743001020100002000020100002000013003813003811200211091010010100001000100000000127021602212952510000100001000010010130039130039130039130039130039
3002413003897400003301300231194172540010100102000010000102000010000506214979148000250130013130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010041000850120127021602212952510000100001000010010130039130039130039130039130039
300241300389740000270130023119417254001010010200001000010200001000050621497914800025013001313003813003812549831262683001020100002000020100002000013003813003811200211091010010100001000100000000127021602212952510000100001000010010130039130039130039130039130039
3002413003810080000300130023119417674001010010200001000010200001019650621502714800025013001613003813003812549831262683001020100002000020100002000013003813003811200211091010010100001000100001000127021602212952510000100001000010010130216130039130404130039130206
300241301249760012348192130027119417254001010010200001000010200001000050621497914800025013001613003813003812549831262683001020100002000020100002000013004113003811200211091010010100001000100001030127021602212952510000100001000010010130039130042130039130039130039

Test 3: throughput

Count: 8

Code:

  fcvtzu w0, d8
  fcvtzu w1, d8
  fcvtzu w2, d8
  fcvtzu w3, d8
  fcvtzu w4, d8
  fcvtzu w5, d8
  fcvtzu w6, d8
  fcvtzu w7, 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)03mmu table walk instruction (07)mmu table walk data (08)09l2 tlb miss instruction (0a)l2 tlb miss data (0b)191e3f51schedule 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)a9acbranch 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
16020440062310100100069725240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100006111511711611400388000080000801004004240042400424004240042
160204400413121002124506025240104801001600041001600205001440132040022400414019920024620125160330200160032200160032400414004111802011009910080100100200111511711611400388000080000801004004240042400424004240042
16020440041311100100032252401048010016000410016002050014401320400224004140041199776199921601202001600322001600324004140041118020110099100801001000012111515211621401028010280000801004012340194400424004240042
1602044004131110010007425240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511711611403028000080000801004004240042400424004240042
1602044004131011110003225240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100006111511711611400388000080000801004004240042400424004240042
1602044004131010010003225240104801001600041001600205001440132140022400414012019977619992160120200160032200160032400414004111802011009910080100100000111511711611400388000080000801004004240042400424004240042
1602044004131110010003225240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511711611400388000080000801004004240042400424004240042
1602044004131010010003225240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511711611400388000080000801004004240042400424004240042
1602044004131010010007425240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511711614400388000080000801004004240042400424004240042
1602044004131110010003225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511711611400388000080000801004004240042400424004240042

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)031e3f51schedule 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)9fld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)dadbddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1600244005531004225240010800101600001016000050144000014002240041400411999632002116001020160000201600004004140041118002110910800101000050205160045400388000080000800104004240042400424004240042
1600244004131008625240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101000050205160034400388000080000800104004240042400424004240042
1600244004131104225240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101000050205160035400388000080000800104004240042400424004240042
1600244004132104225240010800101600001016000050144000014002240041400411999632002116001020160000201600004004140041118002110910800101000350205160255400388000080000800104004240042400424004240042
1600244004131004225240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101000050205160356400388000080000800104004240042400424004240042
1600244004131004225240010800101600001016000050144000014002240041400411999632002116001020160000201600004004140041118002110910800101020050204160354400388000080000800104004240042400424004240042
1600244004131006525240010800101600001016000050144000014002240041400411999632002116001020160000201600004004140041118002110910800101000050204160355400388000080000800104004240042400424004240042
16002440041310010525240010800101600001016000050144000014002240041400411999632002116001020160000201600004004140041118002110910800101000050205160356400388000080000800104004240042400424004240042
1600244004131004225240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101000050205160355400388000080000800104004240042400424004240042
16002440041311124225240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101000050205160345400388000080000800104004240042400424004240042