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

FCVTPU (scalar, S to W)

Test 1: uops

Code:

  fcvtpu w0, s0
  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)03l2 tlb miss data (0b)181e1f3f51schedule 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)l1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
2004541400004325300010002000200018000052254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541400004325300010002000200018000052254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541400004325300010002000200018000052254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541500004325300010002000200018000052254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541400004325300010002000200018000052254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541400004325300010002000200018000152254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541400004325300010002000200018000152254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541400004325300010002000200018000052254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541400004325300010002000200018000052254154124832742000200020005415411110011000000007311611538100010001000542542542542542
2004541400004325300010002000200018000052254154124832742000200020005415411110011000000007311611538100010001000542542542542542

Test 2: Latency 1->2 roundtrip

Code:

  fcvtpu w0, s0
  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)03l2 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)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)a9acc2branch cond mispred nonspec (c5)branch 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
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034113001313003813006412547631262463010020010000200002001000020000130038130038212020110099100101001000010000100000000000131012162212952510000100001000010100130039130039130039130077130077
3020413004797400000013002311941725401001010020000100001002000010000500621497914801034113001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000013002711941725401001010020000100001002000010000500621497914801034113001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000000131012162212952510000100001000010100130039130039130039130039130039
3020413004097400000013002311941725401001010020000100001002000010000500621497914801034113001313003813004312547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000000131012162212952510000100001000010100130039130111130053130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034113001313003813003812547631262463010020010060200002001000020000130038130041112020110099100101001000010000100000000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020210000200002001000020000130038130038112020110099100101001000010000100000000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000030000131012162212952510000100001000010100130039130039130039130039130039
3020513009697400000013002311941725401001010020004100001002000010000500621497914801266113001313003813003812547631262463010020010000200002001000020000130038130039112020110099100101001000010000100000000000131012162212952510000100001000010100130072130039130039130039130039
3020413003897500000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000000131012162212952510000100001000010100130039130039130039130039130039

1000 unrolls and 10 iterations

Result (median cycles for code): 13.0038

retire uop (01)cycle (02)03mmu table walk data (08)09l2 tlb miss data (0b)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)9fld unit uop (a6)l1d cache writeback (a8)a9acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
30024130038974000021601301081194172540010100102000010000102000010000506214979148000251130023130038130041125637312626830182201000020000201000020000130038130043112002110910100101000010100000030012701161112952610000100001000010010130039130039130039130040130040
30024130038974000017701300231207808594024410059201201007313244251186265630339715014119113001313004013003812555110012623630010201000020000201000020000130038130038112002110910100101000010100000030012701161112952510000100001000010010130039130039130039130046130039
300241300389740000483521300231194172540010100102000010000102000010000506214979148000251130013130038130040125500312626830010201000020000201000020491130040130038112002110910100101000010100000000012701161112952510000100001000010010130039130039130039130039130039
30024130038974000060301300231194172540010100172000010000102000010000506223695148000250130013130038130038125498312626830010201000020241201000020000130041130039512002110910100101000010100004000012701481112952510000100001000010010130039130039130039130039130039
300241300389740000001300231194172540010100162000010000102000010000506215123148000250130013130038130038125498312632830010201000020000201000020485130038130038112002110910100101000010100001000012701161112952510000100001000010010130039130039130039130039130039
300241300389740000001300231194172540010100102000010000102000010000506214979148000250130015130038130038125498312647230010201000020000201000020000130038130038112002110910100101000010100000000012701161112952510000100001000010010130039130039130039130039130039
300241300389750000001300231194172540010100102000010000102000010000506214979148000250130013130038130038125498312626830010201000020000201000020000130040130039512002110910100101000010100000030012701161112952510000100001000010010130039130039130039130039130039
300241300389740000001300231194172540010100102000010000102000010000506214979148000250130013130038130038125498312626830010201000020000201000020481130038130038112002110910100101000010100003000012702241112952710000100001000010010130039130039130039130039130039
300241300389740000001300231194172540010100102000010000102000010000506214979148000250130013130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010100000000012701161112952510000100001000010010130039130039130039130039130039
300241300389740000001300231194172540010100102000010000102000010000506214979148000250130013130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010100000000012701161112952510000100001000010010130040130039130039130039130039

Test 3: throughput

Count: 8

Code:

  fcvtpu w0, s8
  fcvtpu w1, s8
  fcvtpu w2, s8
  fcvtpu w3, s8
  fcvtpu w4, s8
  fcvtpu w5, s8
  fcvtpu w6, s8
  fcvtpu w7, s8
  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)03l1i tlb fill (04)mmu table walk instruction (07)l2 tlb miss instruction (0a)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)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 tlb access (a0)l1d tlb miss (a1)l1d cache writeback (a8)a9acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)ea? simd retires (ee)? int retires (ef)f5f6f7f8fd
160204400413100110000003225240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001001115117116114003880000080000801004012440042400424004240042
160204400413110110000003225240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100000001115117170114003880000080000801004004240042400424004240042
160204400413100110000003225240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100000001115117116114003880000080000801004004240042400424004240042
160204400413100110000006025240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001031115117116114003880000080000801004004240042400424004240042
16020440041310011000120069725240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100000001115117116114003880000080000801004004240042400424004240042
160204400413100110000003225240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100000101115117116114003880000080000801004004240042400424004240042
1602044004131101100000032252401048010016000410016002050014401320408654105141058202701032057716283220416270220216292641081411591518020110099100801001002010875311153431142214094781418080000801004004240205411504116541147
160204412393180110019001077791243310811501613761041618685001461696040785411284091520284562067016316820216290620216166041151411671418020110099100801001000207945311153771151114101980000080000801004004240042400424004240042
16020440123311011013913322640738826124419281370162940106163104596146954604110641285413102035512920400163386200163380206162286412424138818180201100991008010010000001133511151172106114075281250080000801004114541140411714075641071
1602044106631901109910689680592141243304805851621281021614865001460270040405407424004119977619992160120200160032200160032400414004111802011009910080100100001001115231279114049681258080000801004027840827410644076340853

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)rob full (74)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 tlb miss (a1)l1d cache writeback (a8)acc2cdcfd2d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
16002440055300154272240010800101600001016000050144000004002240041400411999603202061600102016000020160000400414004111800211091080010100000005020011161311400388000080000800104004240042400424004240042
16002440041300070725240010800101600001016000050144000004002240041400411999603200211600102016000020160000400414004111800211091080010100000005020013161111400388000080000800104004240042400424004240042
1600244004129906425240010800101600001016000050144000004002240041400411999603200211600102016000020160000400414004111800211091080010100000005020012161111400388000080000800104004240042400424004240042
16002440041299080225240010800101600001016000050144000004002240041400411999603200211600102016000020160000400414004111800211091080010100000005020010161113400388000080000800104004240042400424004240042
160024400413000422524001080010160000101600005014400000400224004140041199960320021160010201600002016000040041400411180021109108001010000000502001216914400388000080000800104004240042400424004240042
1600244004131004225240010800101600001016000050144000004002240041400411999603200211600102016000020160000400414004111800211091080010100010005020010161110400388000080000800104004240042400424004240042
1600244004130004225240010800101600001016000050144000014002240041400411999603200211600102016000020160000400414004111800211091080010100000005020010161311400388000080000800104004240042400424004240042
1600244004129904225240010800101600001016000050144000004002240041400411999603200211600102016000020160000400414004111800211091080010100000005020011161310400388000080000800104004240042400424004240042
1600244004130004225240010800101600001016000050144000004002240041400411999603200211600102016000020160000400414004111800211091080010100000005020016161011400388000080000800104004240042400424004240042
1600244004130004225240010800101600001016000050144000004002240041400411999603200211600102016000020160000400414004111800211091080010100000005020013161311400388000080000800104004240042400424004240042