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

FCVTMU (scalar, D to X)

Test 1: uops

Code:

  fcvtmu 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)03191e3f51schedule 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 cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
20045414004325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
20045414094325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
20045414004325300010002000200018000152254154124832742000200020005415411110011000007311611538100010001000542542542542542
20045415004325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
20045414004325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
20045414004325300010002000200018000052254154124832742000200020005415411110011000037311611538100010001000542542542542542
20045414004325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
20045414004325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
20045414004325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
20045414008525300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542

Test 2: Latency 1->2 roundtrip

Code:

  fcvtmu 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)03mmu table walk data (08)09181e3f4f5051schedule 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)696b6d6emap 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)cfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
302041300389740200130059119417025401001010020000100001002000010000500621497914801034130013013003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010001000000000131013164312952510000100001000010100130039130039130039130039130039
302041300389740000130023119417025401001010020000100001002000010000500621497914801034130013013003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010001000000000131013163312954910000100001000010100130039130039130039130039130039
302041300389740000130023119417025401001010020000100001002000010000500621497914801034130013013003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010001000000000131013163312952510000100001000010100130039130039130039130039130039
302041300389740000130023119417025401001010020000100001002000010000500621497914801034130013013003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010001000020000131013162312952910000100001000010100130041130039130039130201130039
302041300409740000130023119417025401001010020000100001002000010000500621497914801034130015013003813003812547631262483010020010000200002001000020000130038130039112020110099100101001000010001000912300131013163312952610000100001000010100130039130039130039130039130039
302041300409740000130023119420025401001010020000100001002000010000500621497914801370130013013003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010001000010000138413164312952510000100001000010100130039130039130039130039130039
302041300389740000130023119417025401001010420000100001002000010000500621497914801034130013013003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010001000000000131014163312952510000100001000010100130039130039130039130039130039
302041300389740000130023119417025401001010020000100001002000010000500621497914801034130013013003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010001000000000131013163312952510000100001000010100130039130040130039130039130039
3020413007197400030130102119417025401001010020000100001002000010000500621497914801034130013013003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010001000000000131013163312952510000100001000010100130039130039130039130039130039
302041300389740000130023119417025401001010020000100001002000010000500621497914801034130013013003813003812547631262463010020010000200002001000020000130038130041112020110099100101001000010021000042320131014163312953310000100001000010100130039130039130049130039130039

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 data (0b)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)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 mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)ec? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
30024130038100800000013002311941725400101001020000100001020000100005062149791480002511300130130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010010000000000127011611129546100000100001000010010130039130039130039130075130039
30024130038100800000013002311941725400101001020000100001020000100005062156511480735611300130130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010010000000000127011611129525100000100001000010010130039130039130039130039130039
300241300381008000000130023119417254001010010200001000010201211000050621497914804334113001301300391300441254983126268300102010000200002010000200001300381300381120021109101001010000100100004021000127011611129525100000100001000010010130039130039130039130039130039
30024130038100800000013002311941725400101001020000100001020000100005062149791480002501300130130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010010000000000127011612129525100000100001000010010130308130070130091130042130039
3002413003897400000013002311941725400101001020000100001020000100005062149791480002511300130130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010010000000000127011611129525100000100001000010010130039130039130039130039130039
3002413003897400000013002311941725400101001020000100001020115100005062149791480002501300130130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010010000006000127021611129525100000100001000010010130041130039130039130039130039
3002413003897400000013002311941725400101001020000100001020000100005062149791480002501300130130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010010000000000127011611129525100000100001000010010130039130075130039130039130076
3002413003897400000013002311941725400101001020000100001020000100005062149791480002511300130130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010010000000000127011611129525100000100001000010010130039130039130039130039130039
30024130038974000000130023119417254001010010200001000010200001000050621497914800025113001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100100000018000127011611129525100000100001000010010130039130039130039130039130039
3002413003897400000013002311941725400101001020000100001020000100005062149791480002511300130130038130077125498312626830010201000020000201000020000130038130038112002110910100101000010010000000000127021611129525100000100001000010010130039130039130039130039130045

Test 3: throughput

Count: 8

Code:

  fcvtmu x0, d8
  fcvtmu x1, d8
  fcvtmu x2, d8
  fcvtmu x3, d8
  fcvtmu x4, d8
  fcvtmu x5, d8
  fcvtmu x6, d8
  fcvtmu 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)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)9fl1d cache writeback (a8)acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1602044006229907625240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001115117116400388000080000801004004240042400424004240042
160204400413000141252401048010016000410016002050014401320400224014040041199773619992160120200160032200160032400414004111802011009910080100100001115117016400388000080000801004004240042400424004240042
16020440041300012025240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001115117016400388000080000801004004240042400424004240042
16020440041300018725240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001115117016400388000080000801004004240042400424004240042
16020440041300020425240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001115117016400388000080000801004004240042400424004240042
16020440041300011825240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001115117016400388000080000801004004240042400424004240042
160204400413000141925240104801001600041001600205001440132040022400414012519977619992160324200160032200160032400414012811802011009910080100100001115117016400388000080000801004004240042400424004240042
1602044004129907625240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001115117016400388000080000801004004240042401294004240042
16020440041299067025240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100001115117016400388000080000801004004240042400424004240042
1602044004130007625240104801001600041001600205001440132040022400414004119977619992160120200160032200160032400414004111802011009910080100100301115117016400388000080000801004004240042400424004240042

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03181e3f51schedule 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)cdcfl1i cache miss demand (d3)l1i tlb miss demand (d4)d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1600244004230000422524001080010160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010101000050200028161628400388000080000800104004240042400424004240042
160024400412990015425240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101013900050200027162726400388000080000800104004240042400424004240042
16002440041300004225240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101013000050200026162714400388000080000800104004240042400424004240042
160024400412990070725240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101048000050200027161427400388000080000800104004240042400424004240042
1600244004129900422524001080010160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010101900050200026162727400388000080000800104004240042400424004240042
1600244004130000422524001080010160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010101000050200026162827400388000080000800104004240042400424012840042
160024400413110012625240010800101607821016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101061000050200016162822400388000080000800104004240042400424004240042
16002440041299004225240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101051000050200027162727400388000080000800104004240042400424004240042
16002440041300004225240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101057000050200013162822400388000080000800104004240042400424004240042
16002440041300004225240010800101600001016000050144000004002240041400411999632002116001020160000201600004004140041118002110910800101047600050200028162727400388000080000800104004240042400424004340042