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 X)

Test 1: uops

Code:

  fcvtpu x0, 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)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)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
2004541408025300010002000200018000052254154124832742000200020005415411110011000107311611538100010001000542542542542542
2004541404325300010002000200018000152254154124832742000200020005415411110011000007311611538100010001000542542542542542
2004541404325300010002000200018000152254154124832742000200020005415411110011000007311611538100010001000542542542542542
2004541494325300010002000200018000152254154124832742000200020005415411110011000007311611538100010001000542542542542542
2004541494325300010002000200018000052254154124832742192200020005415411110011000007311611538100010001000542542542542542
2004541404325300010002000200018000152254154124832742000200020005415411110011000007311611538100010001000542542542542542
2004541404325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
2004541404325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
2004541404325300010002000200018000052254154124832742000200020005415411110011000007311611538100010001000542542542542542
2004541404325300010002000200018000152254154124832742000200020005415411110011000007311611538100010001000542542542542542

Test 2: Latency 1->2 roundtrip

Code:

  fcvtpu x0, 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)03mmu table walk data (08)l2 tlb miss data (0b)18191e3f4f51schedule 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)cfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
3020413003897400000130023119417254010010100200001000010020000100005006214979148010340130013013004413004112547631262503010020010000200002001000020000130038130038112020110099100101001000010001000000300131013162212952510000100001000010100130039130039130039130039130039
3020413003897400000130023119417254010010100200001000010020000100005006214979148010340130013013003813003812547631263073010020010000200002001000020000130038130038112020110099100101001000010001000010000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000130023119417254010010100200001000010020000100005006214979148010340130013013003813003812547631263023010020010000200002001000020000130038130038112020110099100101001000010001000012020131012512212952510000100001000010100130039130039130039130039130620
302041300389741017294130023119420254010010100200001000010020000100005006214979148010340130016013003813003912547631262463010020010000200002001000020000130038130038112020110099100101001000010001000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740000013002311941725401001010020000100001002000010000500621497914801034013001301300381300381254763126273301002001000020000200100002000013003813003811202011009910010100100001000100003018000131012162212952510000100001000010100130040130041130039130039130039
3020413003897400000130023119417254010010100200001000010020000100005006214979148010340130013013003813003812547631262893010020010000200002001000020000130038130038112020110099100101001000010001000000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000130023119417254010010100200001000010020000100005006214979148010341130013013003813003812547631262843010020010000200002021000020000130038130038112020110099100101001000010021000000000131013162212952810000100001000010100130039130039130039130039130040
3020413003897400000130023119417254010010100200001000010020000100005006215123148011501130013013003813003812547661262963026620010065200002001000020000130038130038112020110099100101001000010001000000600131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000130023119417254010010100200001000010020000100005006214979148019570130013013004513004112547631262473010020010000200002001000020000130038130038112020110099100101001000010001000000000131012162212952510000100001000010100130039130039130039130039130039
30204130038974000015130023119417254010010100200001000010020000100005006214979148010340130013013003813003812547631262463026620010000200002001000020000130038130044112020110099100101001000010001000000000131012162212952510000100001000010100130039130039130039130039130039

1000 unrolls and 10 iterations

Result (median cycles for code): 13.0038

retire uop (01)cycle (02)0318191e1f3f4f51schedule 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 access (a0)l1d tlb miss (a1)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9acafc2branch cond mispred nonspec (c5)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
3002413003810080000130023119417254001010010200001000010200001000050621497914800025013001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000000012703161112952510000100001000010010130039130039130039130039130039
3002413003810080000130023119417254001010010200001000010200001000050621497914800025113001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000000012701161112952510000100001000010010130039130039130039130039130039
300241300389740000130023119419254001010010200001000010200001000050621497914800025113001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000000012701161112952510000100001000010010130039130039130039130039130039
30024130038974000013002311941725400101001020000100001020000100005062149791480002501300130130038130038125498312626830010201000020000201000020000130038130038112002110910100101000010001000000022027330012701161112952510000100001000010010130039130039130039130039130039
300241300389740000130023119417254001010010200001000010200001000050621497914800025013001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000000012701161212952510000100001000010010130039130039130039130039130039
300241300389730000130023119417254001010010200001000010200001000050621497914800025113001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000000012701161112952510000100001000010010130063130043130039130039130039
300241300389740000130023119417254001010010200001000010200001000050621497914800025113004401300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000000012701161112952510000100001000010010130039130039130039130039130039
300241300389740000130023119417254001010010200001000010200001000050621497914800025113005901300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000000012701162112952510000100001000010010130039130039130039130039130039
300241300389740000130023119417254001010010200001000010200001000050621593914800025013001501300381300381255013126268300102010000200002010000200001300381300381120022109101001010000100010000000000012701161212952510000100001000010010130042130039130039130039130039
300241300389740000130023119417254001010010200001000010200001000050621497914800025113001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000020000012701161112952510000100001000010010130039130039130039130039130039

Test 3: throughput

Count: 8

Code:

  fcvtpu x0, s8
  fcvtpu x1, s8
  fcvtpu x2, s8
  fcvtpu x3, s8
  fcvtpu x4, s8
  fcvtpu x5, s8
  fcvtpu x6, s8
  fcvtpu x7, s8
  mov x8, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.5006

retire uop (01)cycle (02)03l2 tlb miss data (0b)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)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 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
160204400643000783225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240042
16020440041300003225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240042
160204400412990032252401048010016000410016002050014401321400224004140041199776199921601202001600322001600324004140041118020110099100801001000380111511701600400388000080000801004004240042400424004240042
160204400412990543225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240042
160204400413000213225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240042
16020440041300003225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240042
16020440041300003225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240126
160204400412990123225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240042
16020440041300033225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240042
160204400413000543225240104801001600041001600205001440132140022400414004119977619992160120200160032200160032400414004111802011009910080100100000111511701600400388000080000801004004240042400424004240042

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03mmu table walk data (08)1e3a3f51schedule 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)dbddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
160024400553000004472524001080010160000101600005014400001400224004140041199963200211600102016000020160000400414004111800211091080010100005020616035400388000080000800104004240042400424004240042
16002440041300000422524001080010160000101600005014400001400224004140041199963200211600102016000020160000400414012911800211091080010100005020616064400388000080000800104004240042400424004240042
16002440041300000422524001080191160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010100035020616084400388000080000800104004240042400424004240042
160024400412990120632524001080010160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010100105020616075400388000080000800104004240042400424004240042
16002440041300137506617124001080010160202101600005014400001400224004140041199963200211600102016000020160000400414004111800211091080010100035020516046400388000080000800104004240042400424004240042
160024400413000007072524001080010160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010100005020416046400388000080000800104004240042400424004240042
160024400413000120422524001080010160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010102335020616065400388000080000800104004240042400424004240042
16002440041300000422524001080010160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010100005020716086400388000080000800104004240042400424004240042
16002440041299000422524001080010160000101600005014400000400224004140041199963200211600102016000020160000400414004111800211091080010100005020516077400388000080000800104004240042400424004240042
16002440041300000422524001080010160000101600005014400000400224004140041199963200211602142016000020160000400414004111800211091080010100005020616066400388000080000800104004240042400424004240042