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, S to W)

Test 1: uops

Code:

  fcvtzu 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)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)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
20045414043253000100020002000180000522541541248327420002000200054154111100110000007311611538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110000007311611538100010001000542542542542542
20045414043253000100020002000180000522541541248327420002000200054154111100110000007311611538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110000007311611538100010001000542542542542542
20045414064253000100020002000180001522541541248327420002000200054154111100110000007311611538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110000007311611538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110000107311611538100010001000542542542542542
20045414043253000100020002000180000522541541248327420002000200054154111100110000007311611538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110000007311611538100010001000542542542542542
20045414043253000100020002000180001522541541248327420002000200054154111100110000007311611538100010001000542542542542542

Test 2: Latency 1->2 roundtrip

Code:

  fcvtzu 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)03mmu table walk data (08)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)st unit uop (a7)l1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd0d5map dispatch bubble (d6)daddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
302041300389740000001300231194172540100101002000010000100200001000050062149791480103401300131300381300381254836126242301002001000220006200100022000613003913003811202011009910010100100001000010000000001111317021601112953410000100001000010100130039130039130039130039130043
3020413003897600000013002311941725401001010020000100001002000010000500621497914801034113001313003813003812548371262423010020010002200062001000020000130043130038112020110099100101001000010000100000003000001310121602212957710000100001000010100130039130039130039130039130039
302041300389740000001300231194172540100101002000010000100200001000050062149791480103411300131300381300381254763126246301002001000020000200100002000013003813003811202011009910010100100001000010000000000001310121602212952510000100001000010100130039130039130039130039130039
302041300389740000001300231194172540100101002000010000100200001000050062149791480103401300131300381300381254763126246301002001000020000200100002000013004113003811202011009910010100100001000010000000000011310121602212952510000100001000010100130039130039130039130039130039
302041300389740000001300231194172540100101002000010000100200001000050062149791480103411300131300381300381254763126332301002001000020000200100002000013003813003811202011009910010100100001000010000000000001310121602212952510000100001000010100130039130039130039130039130039
302041300389740000001300311194172540128101002000010000100200001000050062149791480103401300131300381300381254763126260301002001000020000200100002000013003813003811202011009910010100100001000010000000001001310121602212952510000100001000010100130039130039130039130039130040
302041300399740000001300231194172540100101002000010000100200001000050062149791480103411300141300381300381254763126294301002001000020000200100002000013003913003811202011009910010100100001000010004012440100001310121602212952510000100001000010100130040130039130039130039130039
302041300389740000001300231194172540100101002000010000100200001000050062149791480103411300131300381300381254763126295301002001000020000200100002000013003813003811202011009910010100100001000010000000000001310121602212952510000100001000010100130039130039130039130039130039
302041300389740000001300231194172540100101002000010000100200001000050062149791480103411300131300381300381254793126284301002001000020000200100002000013003813003811202011009910010100100001000010000000000001310121602212953210000100001000010100130039130042130039130039130039
302041300389740000001300231194172540100101002000010000100200001000050062149791480103411300131300381300381254763126276301002001000020000200100002000013003813003811202011009910010100100001000010000000000001310121602212952510000100001000010100130039130039130039130039130039

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 access (a0)l1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acbranch 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
30024130038974000000130023119417254001010010200001000010200001000050622454814802413113001301300381300381255593126268300102010000200002010000200001300381300381120021109101001010000100010000300012972161112952510000100001000010010130039130039130039130039130039
30024130038974000000130023119417254001010010200001000010200001000050621497914800025013001301301281300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000012701161112952510000100001000010010130039130042130045130040130039
30024130038974000000130023119417254001010010200001000010200001000050621507514800025013001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000012701161112952510000100001000010010130039130039130039130039130039
30024130038975000000130023119417254001010010200001000010200001000050621497914800025113001301300381300381254983126268301722010000200002010000200001300381300381120021109101001010000100010000003012701161112952510003100001000010010130039130039130039130039130039
30024130038974000000130023119417254001010010200001000010200001000050621507514800025113001301300381300381254983126293300102010000200002010000200001300381300381120021109101001010000100010000000012701161112952510000100001000010010130039130039130039130039130090
30024130038974000000130023119417254001010010200001000010200001000050622388714803081113001301300381300381255533126268300102010000200002010000200001300381300381120021109101001010000100010000000012701161112952510000100001000010010130039130039130039130039130039
30024130038975000000130023119417254001010010200001000010200001004950621584314800138013001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000012701161112952510000100001000010010130039130039130039130039130039
30024130038974000000130023119417254001010010200001000010200001000050621502714800025113001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000012701161112952510000100001000010010130039130039130039130039130039
30024130038974000000130023119417254001010010200001000010200001000050621497914800025013001301300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100010000000012701161112952510000100001000010010130039130039130039130039130039
30024130038974000000130023119417254001010010200001000010200001000050621502714800025113001301300381300381254983126270300102010000200002010000200001300381300381120021109101001010000100010000000012701162112952510000100001000010010130039130039130039130039130039

Test 3: throughput

Count: 8

Code:

  fcvtzu w0, s8
  fcvtzu w1, s8
  fcvtzu w2, s8
  fcvtzu w3, s8
  fcvtzu w4, s8
  fcvtzu w5, s8
  fcvtzu w6, s8
  fcvtzu 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)03mmu table walk data (08)l2 tlb miss data (0b)18191e1f3f51schedule 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)acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1602044006231000000032252401048010016000410016002050014401320400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042
1602044004131000000032252401048010016000410016002050014401320400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042
16020440102310000000322524010480100160004100160020500144013214002240041400411997761999216012020016003220016003240041400411180201100991008010010000011151174701600400388000080000801004004240042400424004240042
1602044004131100000032252401048010016000410016002050014401320400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042
1602044004131010000032252401048010016000410016002050014401320400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042
1602044004131100000032252401048010016000410016002050014401321400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042
1602044004131000000032252401048010016000410016002050014401321400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042
1602044004131000000032252401048010016000410016002050014401320400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042
1602044004131100000032252401048010016000410016002050014401320400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042
1602044004131100000032252401048010016000410016002050014401320400224004140041199776199921601202001600322001600324004140041118020110099100801001000001115117001600400388000080000801004004240042400424004240042

1000 unrolls and 10 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)mmu table walk data (08)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)5f60696d6emap 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)ld unit uop (a6)l1d cache writeback (a8)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)ea? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
16002440055311000012422524001080010160000101600005014400000040022400414004119996320021160010201600002016000040041400411180021109108001010000005020141671240038800000080000800104004240042400424004240042
1600244004131000000422524001080010160000101600005014400000140022400414004119996320021160010201600002016000040041400411180021109108001010000005020716121140038800000080000800104004240042400424004240042
160024400413100000042252400108001016000010160000501440000014002240041400411999632002116001020160000201600004004140041118002110910800101000000502051691040038800000080000800104004240042400424004240042
1600244004131000010422524001080010160000101600005014400000140022400414004119996320021160010201600002016000040041400411180021109108001010000005020121611840038800000080000800104004240042400424004240042
16002440041310000004225240010800101600001016000050144000001400224004140041199963200211600102016000020160000400414004111800211091080010100000050201116111140038800000080000800104004240042400424004240042
16002440041310000004225240010800101600001016000050144000001400224004140041199963200211600102016000020160000400414004111800211091080010100000050201016111040038800000080000800104004240042400424004240042
1600244004132200000422524001080010160000101600005014400000040022400414004119996320021160010201600002016000040041400411180021109108001010000005020111611740038800000080000800104004240042400424004240042
1600244004131100000422524001080010160000101600005014400000140022400414004119996320021160010201600002016000040041400411180021109108001010000005020716111240038800000080000800104004240042400424012840042
1600244004131100000422524001080010160000101600005014400000140022400414004119996320021160010201600002016000040041400411180021109108001010000005022916111140038800000080000800104004240042400424004240042
16002440041310000004225240010800101600001016000050144000000400224004140041199963200211600102016000020160000400414004111800211091080010100000050201116111240038800000080000800104004240042400424012640042