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 W)

Test 1: uops

Code:

  fcvtmu 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)03mmu table walk data (08)l2 tlb miss data (0b)18191e1f3f51schedule 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 access (a0)l1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
20045415000000852530001000200020001800005225415412483274200020002000541541111001100000000007311611538100010001000542542542542542
20045414000000432530001000200020001800005225415412483274200020002000541541111001100000010007311611538100010001000542542542542542
20045414000000432530001000200020001800005225415412483274200020002000541541111001100000000007311611538100010001000542542542542542
20045414000000432530001000200020001800005225415412483274200020002000541541111001100000000007311611538100010001000542542542542542
20045414000000432530001000200020001800005225415412483274200020002000541541111001100000000007311611538100010001000542542542542542
20045414000000432530001000200020001800005225415412483274200020002000541541111001100000000007311611538100010001000542542542542542
20045414000000432530001000200020001800005225415412483274200020002000541541111001100000000007311611538100010001000542542542542542
20045414000000432530001000200020001800005225415412483274200020002000541541111001100000002327312511538100010001000542542542542542
2004541401100043253274100020002000180000562541541248330420002000200054154111100110002200043007311611538100010001000621542542578542
20045415000000432530001000200020001800005225415412483274200020002214541541111001100000000007311611538100010001000542542542542621

Test 2: Latency 1->2 roundtrip

Code:

  fcvtmu 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)03l1i tlb fill (04)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)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)acbranch 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
3020413003897410000013002311945325401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000131013162212952510000100001000010100130039130039130039130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000131012162212952510000100001000010100130039130039130039130039130039
3020513003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038212020110099100101001000010000100000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000131012165212952910000100001000010100130039130039130039130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000013010111941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100020000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262463010020010000200002001000020000130038130038112020110099100101001000010000100000000131012162212952510000100001000010100130039130039130039130083130039
3020413003897400000013002311941738401001010020000100001002000010000500621497914801703013001313003813011412547731262463026920010000200002001000020000130038130038112020110099100101001000010000100000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400000013002311941725401001010020000100001002000010000500621497914801034013001313003813003812547631262623010020010067200002001000020000130038130038112020110099100101001000010000100000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740000984013002311941725401001010020000100001002000010000500621497914801034013001313003813003812548231262463010020010000200002001000020000130038130038112020110099100101001000010000100000000131012162212952510000100001000010100130039130039130039130039130039

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)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)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)acbranch 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
300241300389740000013002311941725400101001020000100001020000100005062150751480002511300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000101000000012704163312952510000100001000010010130039130039130039130039130039
3002413003897400001513002311941725400101001020000100001020000100005062149791480002511300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000101000030012703163312952510000100001000010010130039130039130039130039130147
300241300389740000013002311941725400101001020000100001020000100005062154441480002501300131300391300381255683126268300102010000200002010000200001300381300381120021109101001010000101000000012703163412952510000100001000010010130039130039130039130039130039
300241300389740000013002311941725400101001020000100001020000100005062149791480002511300131300381300411255043126268300102010000200002010000200001300381300381120021109101001010000101000010012703163412952510000100001000010010130039130039130039130039130039
300241300389740000013002311941725400101001020000100001020000100005062149791480002511300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000101000020012703163312952510000100001000010010130039130039130039130039130041
300241300389740000013002311941725400101001020000100001020000100005062149791480002501300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000101000000012704163312952510000100001000010010130039130039130039130039130039
3002413004597400001213002311941725400101001020000100001020000100005062149791480002511300491300381300381254993126268300102010000200002010000200001300381300381120021109101001010000101000000012704163312952510000100001000010010130040130039130039130039130076
300241300389740000013002311941725400101001020000100001020000100005062149791480002501300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000101000010012703163312952510000100001000010010130039130039130039130039130039
300241300389740000013002311941725400101001020000100001020000100005062149791480002501300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000101000020012702163412952510000100001000010010130039130039130039130039130040
300241300389740000013002311941725400101001020000100001020000100005062149791480002511300131300381300381254983126268301802010000200002010000200001300381300381120021109101001010000101000050012703163312952510000100001000010010130039130039130039130039130039

Test 3: throughput

Count: 8

Code:

  fcvtmu w0, d8
  fcvtmu w1, d8
  fcvtmu w2, d8
  fcvtmu w3, d8
  fcvtmu w4, d8
  fcvtmu w5, d8
  fcvtmu w6, d8
  fcvtmu 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 data (08)l2 tlb miss data (0b)181e1f3a3f51schedule 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)6061696d6emap 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 miss (a1)l1d cache writeback (a8)acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd0d2d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)ea? simd retires (ee)? int retires (ef)f5f6f7f8fd
16020440075310000000372524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041118020110099100801001000000111511700016004003880000080000801004004240042400424004240042
16020440041310100000322524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041118020110099100801001000000111511700016004003880000080000801004004240042400424004240042
1602044004131000000012962524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041118020110099100801001000000111511700016004003880000080000801004004240042400424004240042
16020440041311001198016782524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041218020110099100801001000030111511700016004003880000080000801004004240042400424004240042
16020440041310000000742524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041118020110099100801001000100111511700016004003880188080000801004028640124400424004240042
1602044012231300002680322524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041118020110099100801001000132111511700016004003880000080000801004004240042400424004240042
16020440041310000000322524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041118020110099100801001000000131511700016004003880000080000801004004240042400424004240042
160204400413100001200742524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041118020110099100801001000400111511700016004003880000080000801004004240042400424004240042
16020440041311000000322524010480100160004100160020500144013200400224004140041199776199921601202001600322001600324004140041118020110099100801001000000111511700016004003880000080000801004004240042400424004240042
160204400413110000006972524010480100160196100160020500144013210400224004140041199776199921601202001600322001600324004140041118020110099100801001000000111511700016004003880000080000801004004240042400424004240042

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03191e3f51schedule 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)696b6d6emap 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)acc2cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
16002440042310072422524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100000502021622400388000080000800104004240042400424004240042
1600244004132206702524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100001502021622400388000080000800104004240042400424004240042
1600244004131006422524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100000502021622400388000080000800104004240042400424004240042
1600244004131000422524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100000502021632400388000080000800104004240042400424004240042
16002440041311005172524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100000502031623400388000080000800104004240042400424004240042
1600244004131106422524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100000502051633400388000080000800104004240042400424004240042
16002440041310001232524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100000502031633400388000080000800104004240042400424004240042
1600244004131100422524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100000502021623400388000080000800104004240042400424004240042
1600244004131000422524001080010160000101600005014417904002204004140041199963200211600102016000020160000400414004111800211091080010100000502031622400388000080000800104004240042400424004240042
16002440041310027702524001080010160000101600005014400004002204004140041199963200211600102016000020160000400414004111800211091080010100000502021632400388000080000800104004240042400424004240042