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, fixed-point, D to D)

Test 1: uops

Code:

  fcvtzu d0, d0, #3
  movi v0.16b, 1
  movi v1.16b, 2

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 1.000

Issues: 1.000

Integer unit issues: 0.000

Load/store unit issues: 0.000

SIMD/FP unit issues: 1.000

retire uop (01)cycle (02)03l2 tlb miss data (0b)1e3f4e51schedule uop (52)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 simd alu (9a)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0ec? simd retires (ee)f5f6f7f8fd
100430372400103254725100010001000398160130183037303724143289510001000100030373037111001100000731161126290100030383038303830383038
10043037240061254725100010001000398160130183037303724143289510001000100030373037111001100010731161126290100030383038303830383038
100430372300103254725100010001000398160130183037303724143289510001000100030373037111001100010731161126290100030383038303830383038
10043037240061254725100010001000398160030183037303724143289510001000100030373037111001100000731161126290100030383038303830383038
10043037240061254725100010001000398160130183037303724143289510001000100030373037111001100000731161126290100030383038303830383038
10043037230061254725100010001000398160030183037303724143289510001000100030373037111001100000731161126290100030383038303830383038
10043037230061254725100010001000398160030183037303724143289510001000100030373037111001100000731161126290100030383038303830383038
10043037240061254725100010001000398160030183037303724143289510001000100030373037111001100000731161126290100030383038303830383038
10043037230061254725100010001000398160130183037303724143289510001000100030373037111001100000731161126290100030383038303830383038
10043037230061254725100010001000398160030183037303724143289510001000100030373037111001100000731161126290100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtzu d0, d0, #3
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03l2 tlb miss data (0b)18191e1f3f4e51schedule 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)inst simd alu (9a)9fl1d tlb miss (a1)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)ec? simd retires (ee)? int retires (ef)f5f6f7f8fd
102043003723300000612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000046060710116112963300100001003003830038300383003830038
102043003724500000612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000065000710116112963300100001003003830038300383003830038
102043003723300000612953725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000039060710116112963300100001003003830038300383003830038
1020430037232000007262954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000044000710116112963320100001003003830038300383003830038
1020430037232000906129547251010010010000100100005004277160030018300373003728264628763101002001000020010000300373003711102011009910010010000100000420007101161129633110100001003003830038300383003830038
102043003723300000612954725101001001000010010000500427716003005430037300372826432874510100200100002001000030037300371110201100991001001000010000062000710116112963300100001003003830038300383003830038
102043003723300012061295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000004000710116112963300100001003003830038300383003830038
102043003723300041706129547251010010010000100100005004277160130018300373003728264232874510100200100002001000030037300371110201100991001001000010000058000710116112963300100001003003830038300383003830038
102043003723300000612954725101251001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000069000710216112963300100001003003830038300383013530038
10204300372330002701262954725101001001000012210000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000046060710116112963300100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03l1i tlb fill (04)l2 tlb miss data (0b)191e1f3f4e51schedule 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)inst simd alu (9a)9fl1d tlb miss (a1)l1d cache writeback (a8)a9acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
100243003722510000712954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229690010000103003830038300383003830038
1002430037225000002082954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003722500000612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229667010000103003830038300383003830038
100243003722500000612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003722400000612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003722500000612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162129629010000103003830038300383003830038
1002430037225000001032954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
1002430037224000007262954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003722500000612954725100101010000101000055427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003722500000612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtzu d0, d8, #3
  fcvtzu d1, d8, #3
  fcvtzu d2, d8, #3
  fcvtzu d3, d8, #3
  fcvtzu d4, d8, #3
  fcvtzu d5, d8, #3
  fcvtzu d6, d8, #3
  fcvtzu d7, d8, #3
  movi v8.16b, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.2505

retire uop (01)cycle (02)0318191e3f51schedule 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)simd prf full (72)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)inst simd alu (9a)9fld unit uop (a6)l1d cache writeback (a8)acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0e8? simd retires (ee)? int retires (ef)f5f6f7f8fd
80204200681550002512580108100800081008002050064013202002020039200399977069990801202008003220080032200392003911802011009910010080000100006111511821633200360800001002004020040200402004020040
80204200391551012532580108100800081008002050064013202002020039200399977069990801202008003220080032200392003911802011009910010080000100000111511831633200360800001002004020040200402004020040
80204200391550002232580108100800081008002050064013202002020039200399977069990801202008003220080032200392003911802011009910010080000100000111511831633200360800001002004020040200402004020040
8020420039156000302580108100800081008002050064013202002020039200399977069990801202008003220080032200392003911802011009910010080000100000111511831643200360800001002004020040200402004020040
80204200391550001352580108100800081008002050064013212002020039200399977069990801202008003220080032200392003911802011009910010080000100000111511841634200360800001002004020040200402004020040
8020420039155000512580108100800081008002050064013212002020039200399977069990801202008003220080032200392003911802011009910010080000100000111511843743200360800001002004020040200402004020040
8020420039156000932580108100800081008002050064013202002020039200399977069990801202008003220080032200392003911802011009910010080000100020111511841634200360800001002004020040200402004020040
8020420039156000932580108100800081008002050064013202002020039200399977069990801202008003220080032200392003911802011009910010080000100000111511841643200360800001002004020040200402004020040
80204200391550001562580108100800081008002050064013202002020039200399977069990801202008003220080032200392003911802011009910010080000100000111511841624200360800001002004020040200402004020040
8020420039155000932580108100800081008002050064013202002020039200399977069990801202008003220080032200392003911802011009910010080000100000111511831644200360800001002004020040200402004020040

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.2505

retire uop (01)cycle (02)03l2 tlb miss data (0b)1e3f5051schedule 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)inst simd alu (9a)9fl1d tlb access (a0)l1d tlb miss (a1)l1d cache writeback (a8)acc2cfd0d2l1i cache miss demand (d3)d5map dispatch bubble (d6)d9dadbddfetch restart (de)e0eaeb? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200511550075120023258001010800001080000506400000120020200392003999963100198001020800002080000200392003911800211091010800001000373050200001516000166200360080000102004020040200402004020040
800242003915600402002325800101080000108000050640000012002020039200399996310019800102080000208000020039200391180021109101080000100000050200001616000616200360080000102004020040200402004020040
80024200391550047120023258001010800001080000506400000120020200392003999963100198001020800002080000200392003911800211091010800001000130502230016162111552003615080000102004020040200402004020040
800242003915500400258001010800001080000506400000120020200392003999963100198001020800002080000200392003911800211091010800001000015050200001616000166200360080000102004020040200402004020040
80024200391550558400258001010800001080000506400000120020200392003910005310019800102080000208000020039200391180021109101080000100003050200001616000166200360080000102004020040200402004020040
80024200391551040025800101080000108000050640000102002020039200399996310019800102080000208000020039200391180021109101080000100020050200001616200166200360080000102004020040200402004020040
8002420039156004002580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010000605020000516000166200360080000102004020040200402004020040
80024200391550040025800101080000108000050640000012002020039200399996310019800102080000208000020039200391180021109101080000100040005020000616000616200360080000102004020040200402004020040
80024200391550075802580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010000005020000616000166200360080000102004020040200402004020040
8002420039155012400258001010800001080000506400000020020200392003999963100198001020800002080000200392019011800211091010800001000100502000016160001616200360080000102004020040200402004020040