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

XTN (4S)

Test 1: uops

Code:

  xtn v0.4h, v0.4s
  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)03181e3f4e51schedule 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
10042037160786116862510081000100026452102018203720371571318951000100010002037203711100110000073316221786100020382038203820382038
10042037160015616862510001000100026452102018203720371571318951000100010002037203711100110000073216221786100020382038203820382038
1004203716006116862510001000100026452102018203720371571318951000100010002037203721100110000073216221786100020382038203820382038
1004203715006116862510001000100026452102018203720371571318951000100010002037203711100110000073216221786100020382038203820382038
1004203715006116862510001000100026452102018203720371571318951000100010002037203711100110000073216221786100020382038203820382038
1004203716006116862510001000100026452102018203720371571318951000100010002037203711100110000073216221786100020382038203820382038
1004203715006116862510001000100026452112018203720371571318951000100010002037203711100110000073216221786100020382038203820382038
1004203715006116862510001000100026452112018203720371571318951000100010002037203711100110000073216221786100020382038203820382038
1004203715006116862510001000100026452102018203720371571318951000100010002037203711100110000073216221786100020382038203820382038
10042037160027116862510001000100026452102018203720371571318951000100010002037203711100110000373216221786100020382038203820382038

Test 2: Latency 1->2

Code:

  xtn v0.4h, v0.4s
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 2.0037

retire uop (01)cycle (02)03mmu table walk data (08)09l2 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)9fld unit uop (a6)l1d cache writeback (a8)acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
1020420323164101481056440500019642182102441401009614611368718285747312001820037200371842131874510426226113302301099820466203237110201100991001001000010000000087004811119791100001002041520371204672042220409
1020420467164010000061196862510100100100001001000050028475210200182003720037184213187451010020010000200100002003720037111020110099100100100001007601000071001161119791100001002003820038200382003820038
10204200371550000000611968625101001001000010010000500284752102001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071001161119791100001002003820038200382003820038
1020420037156000000089196863010100100100001001000050028475210200182003720037184213187451010020010000200100002003720037111020110099100100100001000000007100139531119791100001002003820038200382003820038
102042003716100000004811968625101001001000010010000500284752112001820037200371842131874510100200100002001016720037200371110201100991001001000010000000071001161119791100001002003820038200382003820038
10204200371550000012006119686251010010010000100100005002847521020018200372003718421318745101002001000020010000200372003711102011009910010010000100009600071001161119791100001002003820038200382003820038
10204200371550000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000900071001161119791100001002003820038200382003820038
10204200371550000000611968625101001001000010010000500284752102001820037200371842131874510100200100002001000020037200371110201100991001001000010000900071001161119791100001002003820038200382003820038
102042003715500000006119686251010010010000100100005002847521120018200372003718421318745101002001000020010000200372003711102011009910010010000100001500071001161119791100001002003820038200382003820038
10204200371560000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071001161119791100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire uop (01)cycle (02)03mmu table walk data (08)09l2 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 miss ld (a3)l1d cache writeback (a8)acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002420037156000000611968625100101010000101000050284752102001820084200851844331876710010201000020100002003720037111002110910101000010000006403162219786010000102003820038200382003820038
1002420037155000012018271968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000606402162219786010000102003820038200382003820038
10024200371550000004231968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010001006402162219786010000102003820038200382003820038
1002420037156000000611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000306402162219786010000102003820038200382003820038
1002420037155000000611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
1002420037155000000611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
1002420037155000000611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
1002420037155000000611968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
10024200371550000001031968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038
1002420037155000000891968625100101010000101000050284752102001820037200371844331876710010201000020100002003720037111002110910101000010000006402162219786010000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  xtn v0.4h, v8.4s
  xtn v1.4h, v8.4s
  xtn v2.4h, v8.4s
  xtn v3.4h, v8.4s
  xtn v4.4h, v8.4s
  xtn v5.4h, v8.4s
  xtn v6.4h, v8.4s
  xtn v7.4h, v8.4s
  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)03mmu table walk data (08)l2 tlb miss data (0b)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)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)ld unit uop (a6)l1d cache writeback (a8)a9acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
8020420057155000000292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000000000111511801600200350800001002003920039200392003920039
8020420038156000000292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000000090111511801600200350800001002003920039200392003920039
802042003815500000029258010810080008100800205006401321200192003820038997769989801202008003220080032200382003811802011009910010080000100000001320111511801600200350800001002003920039200392003920039
8020420038155000000292580108100800081008002050064013212001920038200389977699898012020080032200800322003820038118020110099100100800001000002000111511801600200350800001002003920039200392003920039
8020420038155000000292580108100800081008002050064013212001920038200389977699868012020080032200800322003820038118020110099100100800001000000000111511801610200350800001002003920039200392003920039
8020420038156000000292580108100800081008002050064013212001920038200389977699898012020080032200800322003820038118020110099100100800001000001000111511801600200350800001002003920039200392003920039
8020420038156000090292580108100800081008002050064013212001920038200389977699898012020080032200800322003820038118020110099100100800001000000030111511801600200350800001002003920039200392003920039
8020420038155000000712580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000004000111511801600200350800001002003920039200392003920039
8020420038156000000292580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000002000111511801600200350800001002003920039200392003920039
8020420038155000000522580108100800081008002050064013202001920038200389977699898012020080032200800322003820038118020110099100100800001000007030111511801600200350800001002003920039200392003920039

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)l2 tlb miss data (0b)1e3f51schedule 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 cache writeback (a8)acbranch cond mispred nonspec (c5)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
800242005015500039258001010800001080000506400001200190200382003899963100188001020800002080000200382003811800211091010800001010005020316632003580000102003920039200392003920039
800242003815510039258001010800001080000506400000200190200382003899963100188001020800002080000200382003811800211091010800001010005020216232003580000102003920039200392003920090
800242003815510039258001010800921080000506400001200190200382003899963100188001020800002080000200382003811800211091010800001010005020316322003580000102003920039200392003920039
800242003815500067258001010800001080000506400001200190200382003899963100188001020800002080000200382003811800211091010800001010005020616632003580000102003920039200392003920039
800242003815600039258001010800001080000506400000200190200382003899963100188001020800002080000200382003811800211091010800001000005020316262003580000102003920039200392003920039
80024200381560037881258001010800001080000506400000200190200382003899963100188001020800002080000200382003811800211091010800001000005020516332003580000102003920039200392003920039
800242003815500081258001010800001080000506400000200190200382003899963100188001020800002080000200382003811800211091010800001000005020616662003580000102003920039200392003920194
800242003815500039258001010800001080000506400001200190200382003899963100188001020800002080000200382003811800211091010800001020005020316562003580000102003920039200392003920039
800242003815600039258001010800001080000506400000200190200382003899963100188001020800002080000200382003811800211091010800001010005020616562003580000102003920039200392003920039
800242003816600039258001010800001080000506400000200190200382003899963100188001020800002080000200382003811800211091010800001010005020316322003580000102003920039200392003920039