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

FCVTNU (vector, 8H)

Test 1: uops

Code:

  fcvtnu v0.8h, v0.8h
  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)03191e3f4e51schedule 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
1004303724006125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816013018303730372414328951000100010003037303711100110000373116112629100030383038303830383038
1004303724006125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723006125472510001000100039816013018303730372414328951000100010003037303711100110000373116112629100030383038303830383038
1004303723008225472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
10043037230216125472510001000100039816013018303730372414328951000100010003037303711100110000373116112629100030383038303830383038
1004303723036125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723006125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtnu v0.8h, v0.8h
  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)031e3f4e51schedule 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 cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
102043003723308929547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100037101161129633100001003003830229300383003830038
1020430037233094329547251010010010000100100005004277160130018300373003728264328745101002001000020010000300373003711102011009910010010000100007101161129633100001003003830038300383003830038
102043003723206129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100007101161129633100001003003830038300383003830038
1020430037233126129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100007101161129633100001003003830038300383003830038
1020430037232017329547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100007101161129633100001003003830038300383003830038
1020430037233053629547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100337101161129633100001003003830038300383003830038
102043003723306129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100007101161129633100001003003830038300383003830038
102043003723306129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100007101161129633100001003003830038300383003830038
102043003723336129547251010010010000100100005004277160030018300373003728264328745102522001000020010000300373003711102011009910010010000100007101161129633100001003003830038300383003830038
102043003723206129547251010010010000100100005004277160030018300373003728264328745101002001000020010000300373003711102011009910010010000100007101161129633100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)031e3f4e51schedule 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)inst simd alu (9a)9fl1d cache writeback (a8)accfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
100243003723306129547251001010100001010000504277160103001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038
100243003723306129547251001010100001010000504277160003001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038
100243003723306129547251001010100001010000504277160003001830037300372828632876710010201000020100003003730037111002110910101000010006680216222962910000103003830038300383003830038
100243003723306129547251001010100001010000504277160103001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038
100243003722506629547251001010100001010000504277160103001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038
100243003722506129547251001010100001010000504277160103001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038
100243003722506129547251001010100001010000504277160103001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038
100243003722506129547251001010100001010000504277160103001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038
100243003722506129547251001010100001010000504277160103001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038
100243003722506129547251001010100001010000504277160103001830037300372828632876710010201000020100003003730037111002110910101000010006400216222962910000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtnu v0.8h, v8.8h
  fcvtnu v1.8h, v8.8h
  fcvtnu v2.8h, v8.8h
  fcvtnu v3.8h, v8.8h
  fcvtnu v4.8h, v8.8h
  fcvtnu v5.8h, v8.8h
  fcvtnu v6.8h, v8.8h
  fcvtnu v7.8h, v8.8h
  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)03191e1f3f51schedule 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 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
8020420039155000932580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151181160020036800001002004020040200402004020040
8020420039155000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
8020420039155000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
80204200391550002352580108100800081008002050064013202002020039201009977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
8020420039155000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000311151180160020036800001002004020040200402004020040
8020420039160000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
8020420039156000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151181160020036800001002004020040200402004020040
80204200391560306952580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180166020036800001002004020040200402004020040
8020420039155000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
8020420039155000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03191e1f3f51schedule 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)5e696d6emap 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)ld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200401550001025258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010000005020416112003680000102004020040200402004020040
80024200391550120298258001010800001080000506400000200202009920039999631001980010208000020800002003920039118002110910108000010000105038139112003680000102010120040200402004020040
8002420039155000105258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010000005020116112003680000102004020040200402004020040
8002420039155000624258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010000035020116212003680000102004020040200402004020040
800242003915500040258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010000005020216222003680000102004020040200402004020040
80024200391550132881569428010910802901080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010022005020116112003680000102004020040200402004020040
8002420039155000263258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010000005020116112003680000102004020040200402004020040
8002420039156000124258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010000105020116112003680000102004020040200402004020040
800242003915500084258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010000005020216122003680000102004020040200402004020040
800242003915500040258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010000005020116222003680000102004020040200402004020040