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

FCVTAU (vector, 4H)

Test 1: uops

Code:

  fcvtau v0.4h, v0.4h
  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)031e3f4e51schedule 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)e0? simd retires (ee)f5f6f7f8fd
1004303723015625472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723246125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372408225472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723010325472510001000100039816003018303730372414328951000100010003037303711100110001073116112629100030383038303830383038
100430372406125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372466125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtau v0.4h, v0.4h
  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)031e1f3f4e51schedule 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)60696b6d6emap 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)9d9fl1d tlb access (a0)l1d tlb miss (a1)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
102043003723300612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100000100000071021622296330100001003003830038300383003830038
102043003723300612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100000100003071021622296330100001003003830038300383003830038
102043003723300612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100000100008971021632296330100001003003830038300383003830038
102043003724100612954725101001001000010010000500427716003001803003730037282643287451010020010000200100003003730037111020110099100100100000100000071021622296330100001003003830038300383003830038
1020430037232001032954725101001001000010010000500427716003001803003730037282643287451010020010000200100003003730037111020110099100100100000100001071021622296330100001003003830038300383003830038
102043003723300612954725101001001000010010000500427716003001803003730037282643287451010020010000200100003003730037111020110099100100100000100000071021622296330100001003003830038300383003830038
1020430037232120612954725101001001000010010000500427716003001803003730037282643287451010020010000200100003003730037111020110099100100100000100000071021622296330100001003003830038300383003830038
1020430037232006129547251010010010000100100005004277160030018030037300372826432874510100200100002001000030037300371110201100991001001000001000031371021622296330100001003003830038300383003830038
102043003723300612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100000100000071021622296330100001003003830038300383003830038
102043003724100612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100000100000071021622296330100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03191e3f4e51schedule 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)60696b6d6emap 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)l1d cache writeback (a8)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0ea? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002430037225006129547251001010100001010000504277160130018030037300372828632876710010201000020100003003730037111002110910101000010000006402162229701010000103003830038300383003830133
1002430037224006129547251001010100001010000504277160130018030037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003722500612954725100101010000101000050427716003001803003730037282863287671001020100002010000300373003711100211091010100001000001626402162229629010000103003830038300383003830038
10024300372250061295472510010101000010100005042771600300180300373003728286328767100102010000201000030037300371110021109101010000100000846402162229629010000103003830038300383003830038
10024300372250061295472510010101000010100005042771600300180300373003728286328767100102010000201000030037300371110021109101010000100000816402162229629010000103003830038300383003830038
10024300372250061295472510010101000010100005042771600300180300373003728286328767100102010000201000030037300371110021109101010000100000876402162229629010000103003830038300383003830038
10024300372250061295472510010101000010100005042771600300180300373003728286328767100102010000201000030037300371110021109101010000100000846402162229629010000103003830038300383003830038
1002430037241006129547251001010100001010000504277160130018030037300372828632876710010201000020100003003730037111002110910101000010000036402162229629010000103003830038300383003830038
100243003722500612954725100101010000101000050427716013001803003730037282863287671001020100002010000300373003711100211091010100001000001146402162229629010000103003830038300383003830038
1002430037225006129547251001010100001010000504277160130018030037300372828632876710010201000020100003003730037111002110910101000010000036402162229629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtau v0.4h, v8.4h
  fcvtau v1.4h, v8.4h
  fcvtau v2.4h, v8.4h
  fcvtau v3.4h, v8.4h
  fcvtau v4.4h, v8.4h
  fcvtau v5.4h, v8.4h
  fcvtau v6.4h, v8.4h
  fcvtau v7.4h, v8.4h
  movi v8.16b, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.2506

retire uop (01)cycle (02)031e3f51schedule 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 access (a0)l1d tlb miss (a1)l1d cache writeback (a8)acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8020420058156030258010810080008100800205006401320200202003920039997769990801202008003220080032200392003911802011009910010080000100000011151181160020036800001002004020040200402004020040
8020420039155051258010810080008100800205006401320200202003920039997769990801202008003220080032200392003911802011009910010080000100000011151180160020036800001002004020040200402004020040
8020420039156030258010810080008100800205006401320200202003920039997769990801202008003220080032200392003911802011009910010080000100000011151180160020036800001002004020040200402004020040
8020420039155030258010810080008100800205006401320201002003920039997769990801202008003220080032200392015021802011009910010080000100000311151180160020036800001002004020040200402004020040
80204200391550512580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000019111520211232220045800001002004920050200492004920049
8020420048155064278011610080016100800285006401960200292004920048997699986801282008003820080038200492004811802011009910010080000100000022251281231120045800001002004920050200492005020049
80204200491550642680116100800161008002850064019602002920048200489976109986801282008003820080038200482004811802011009910010080000100000022251291341120045800001002005020049200492005020050
80204200491566106268011610080016100800285006401960200292004820048997699986801282008003820080038200492004811802011009910010080000100000022251281231120046800001002004920049200492004920050
8020420048156064278011610080016100800285006401960200292004820048997699986801282008003820080038200482004811802011009910010080000100000022251281231120045800001002005020049200492004920049
8020420048155064278011610080016100800285006401961200292004920048997699986801282008003820080038200482004811802011009910010080000100000022251281231120046800001002005020050200492004920050

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03mmu table walk data (08)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)6061696d6emap 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 indir (93)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)a9accfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)eb? simd retires (ee)? int retires (ef)f5f6f7f8fd
800242005115600000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020071635200360080000102004020040200402004020040
8002420039161000002112580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020031655200360080000102004020040200402004020040
800242003915500000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020051635200360080000102004020040200402004020040
800252003915500000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020031635200360080000102004020040200402004020040
800242003915500000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020041653200360080000102004020040200402004020040
800242003915500000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020051655200360080000102004020040200402004020040
800242003915600000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020031645200360080000102004020040200402004020040
800242003915500000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020051653200360080000102004020040200402004020040
80024200391610000081725800101080000108000050640000002002020039200399996031001980010208000020800002003920039118002110922101080000100008065020051655200360080000102004020040200402004020040
800242003915500000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211090101080000100000005020051653200360080000102004020040200402004020040