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

FCVTZS (scalar, integer, D to X)

Test 1: uops

Code:

  fcvtzs 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)031e3f51schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch simd uop (57)ldst uops in schedulers (5b)696d6emap 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
200454140432530001000200020001800052254154124832742000200020005415411110011000007331611538100010001000542542542542542
200454140432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542
200454140432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542
200454150432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542
200454140432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542
200454140432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542
200454140432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542
200454140432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542
200454140432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542
200454140432530001000200020001800052254154124832742000200020005415411110011000007311611538100010001000542542542542542

Test 2: Latency 1->2 roundtrip

Code:

  fcvtzs 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)03l2 tlb miss data (0b)1e3f4f51schedule 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)6061696b6d6emap 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)ld unit uop (a6)l1d cache writeback (a8)a9acc2branch 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
302041300389740013005811941725401091010020000100001002000010000500621497914801034001300140130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
3020413003897400130024119417254010010100200001000010020000100005006214979148010340013001301300441300381254763126246301002001000020000202100612000013012213011711202011009910010100100001002100401289878000142212162413140310048100001000010100130039130039130125130135130044
302041300409740013002511941725401001010020000100001002000010000500621497914801034001300130130038130038125476312624930100200100002000020010064200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740013004811941725401001010020000100001002000010000500621497914801034001300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510003100001000010100130039130039130039130039130041
3020413003811611013002311941725401001010020000100001002000010000617621497914805876001300180130038130038125495312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740013002611942225401001010020000100001002000010000500621497914801034001300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740013003811941725401001010020000100001002000010000500621497914801034001300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130039130039130039
302041300389740013005111941725401001010020000100001002000010000500621497914801034001300130130038130038125478312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510025100001000010100130039130039130039130039130039
302041300389740013002411941725401001010020000100001002000010000500621497914801034001300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510029100001000010100130039130135130039130039130039
302041300389740013002311941725401001010020000100001002000010000500621497914801034001300130130038130038125476312624630100200100002000020010000200001300381300381120201100991001010010000100010000000000131012162212952510000100001000010100130039130039130041130039130039

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)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 miss (a1)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)acbranch mispred nonspec (cb)cfd5map dispatch bubble (d6)d9ddfetch restart (de)e0? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)f5f6f7f8fd
30024130038974000000130023119417254001010010200001000010200001000050621497914800140113001313003813003812549831262683001020100002000020100002000013003813003811200211091010010100001001000700240127021605112952510000100001000010010130039130389130046130039130039
3002413003897401400013002311941725400101001020000100001020000100005062149791482116911300131300411303591254983126268300102010000200002010000200001300381300381120021109101001010000100100000001127011601112952510000100001000010010130039130039130039130039130039
3002413037797401000013002311941725400101001020000100001120000100005062149791480002501300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100100000000127011601112952510000100001000010010130042130039130042130043130455
3002413003897400000013002311941725400101001620000100001020000100005062149791480002501300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100100000930127011601112952510000100001000010010130039130039130039130039130039
3002413003897400000013002311941725400101001020000100001020000100005062149791480002501300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100100000000127011601112952510000100001000010010130039130039130039130039130039
3002413003897400000013002311941725400101001020000100001020000100005062151231480002501300131300381300381255003126268300102010000201222010066200001300391300381120021109101001010000100100000000127011602112952510000100001000010010130039130039130039130039130039
3002413003897400000013002311941725400101001020000100001020000100005062149791480002501300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100100000000127011611112952510000100001000010010130039130039130039130039130039
30024130038974000024013002311941725400101001020000100001020000100005062149791480002501300131300381300381254983126268300102010000200002010000200001300381300381120021109101001010000100100000030130611602112952510000100001000010010130039130039130039130039130039
3002413003897400000013002411941738400101001020000100001020000100005062149791480002511300131300741300381254983126268300102010000200002010000200001300381300381120021109101001010000100100000000127011601112952510000100001000010010130039130039130039130039130039
3002413003897400000013002311941725400101001020003100001020000100005062149791480002501300131300381300741254983126268300102010000200002010000200001300381300381120021109101001010000100100000000127011601112952510000100001000010010130039130039130039130039130039

Test 3: throughput

Count: 8

Code:

  fcvtzs x0, d8
  fcvtzs x1, d8
  fcvtzs x2, d8
  fcvtzs x3, d8
  fcvtzs x4, d8
  fcvtzs x5, d8
  fcvtzs x6, d8
  fcvtzs 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)0318191e1f3f51schedule 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)696d6emap 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 miss (a1)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)fetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
160204400633000090697252401048010016000410016002050014401324002240041400411997706199921601202001600322001600324004140041118020110099100801001000001021011151330160400388000080000801004004240042400424004240042
16020440041300003003225240104801001600041001608525001440132400224004140041199770619992160120200160032200160032400414004111802011009910080100100000100011151170160400388000080000801004004240042400424004240042
1602044004130000003225240104801001600041001600205001440132400224004140041199770620173160120200160032200160032400414004111802011009910080100100000000011151170160400388000080000801004020640042400424004240042
16020440041300002103225240104801001600041001608245001440132400224004140041199770619992160120200160032200160032400414004111802011009910080100100000000011151170160400388000080000801004004240042403604004240042
1602044004129900003225240104801001600041001600205001440132400224004140041199770619992160120200160032200160032400414004111802011009910080100100000000011151170160400388000080000801004004240042400424004240042
16020440041300002107425240104801001600041001600205001440132400224004140041199770619992160120200160032200160032400414004111802011009910080100100000000011151170160400388000080000801004004240042400424004240042
16020440041300000069725240104801001600041001600205001440132400224004140041199770619992160120200160032200160032400414004111802011009910080100100000000011151170160400388000080000801004004240042400424004240042
1602044004129900003225240104801001600041001600205001440132400224004140041199770619992160120200160032200160032400414004111802011009910080100100000000011151170160400388000080000801004004240042400424004240042
16020440041300000032252401048010016018810016002050014401324002240041400411997702819992160120200160032200160032400414004111802011009910080100100000100011151170160400388000080000801004004240042400424004240042
1602044004130000123523225240104801001600041001600205001440132400224004140041199770619992160120200160032200160032400414004111802011009910080100100000000011151170160400388000080000801004004240042400424004240042

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)l2 tlb miss data (0b)3f51schedule 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 cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
16002440043300004225240010800101600001016000050144000001400224004140041199963200211600102016000020160000400414004111800211091080010100138502012161113400388000080000800104004240042400424004240042
160024401663000042252400108001016000010160000501440000014002240041400411999632002116001020160000201600004004140041118002110910800101000502013161111400388000080000800104004240042400424004240042
16002440041300004225240010800101600001016000050144000000400224004140041199963200211600102016000020160000400414004111800211091080010100243502013161114400388000080000800104004240042400424004240042
16002440041300004225240010800101600001016000050144000000400224004140041199963200211600102016000020160000400414004111800211091080010100129502011161211400388000080000800104004240042400424004240042
160024400413000042225240010800101600001016000050144000001400224004140041199963200211600102016000020160000400414004111800211091080010100234502010161013400388000080000800104004240042400424004240042
160024400412990042252400108001016000010160000501440000004002240041400411999632002116001020160000201600004004140041118002110910800101022222502012161111400388000080000800104004240042400424004240042
16002440041300004225240010800101600001016000050144000000400224004140041199963200211600102016000020160000400414004111800211091080010100207502011161214400388000080000800104004240042400424004240042
16002440041300004225240010800101600001016000050144000000400224004140041199963200211600102016000020160000400414004111800211091080010100222502013161313400388000080000800104004240042400424004240042
16002440041300004225240010800101600001016000050144000001400224004140041199963200211600102016000020160000400414004111800211091080010100222502012161013400388000080000800104004240042400424004240042
16002440041299004225240010800101600001016000050144000000400224004140041199963200211600102016000020160000400414004111800211091080010100153502013161113400388000080000800104004240042400424004240042