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

SXTL2 (8H)

Test 1: uops

Code:

  sxtl2 v0.8h, v0.16b
  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)03mmu table walk data (08)0918191e1f3a3f4e51schedule 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 tlb access (a0)ld unit uop (a6)l1d cache writeback (a8)acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
1004203715000000017416862510001000100026452112018203720371571318951000100010002037203711100110000000073116111786100020382038203820382038
100420371500000006116862510001000100026452112018203720371571318951000100010002037203711100110000000073116111786100020382038203820382038
1004203715000000010316862510001000100026452112018203720371571318951000100010002037203711100110000000073116111786100020382038203820382038
100420371500000006116862510001000100026452112018203720371571318951000100010002037203711100110000000073116111786100020382038203820382038
1004203715000012006116862510001000100026452112018203720371571318951000100010002037203711100110000000073116111786100020852038203820382038
100420371600000006116862510001000100026452112018203720371571318951000100010002037203721100110000000073116111786100020382038203820382038
100420371600000006116862510001000100026452112018203720371571318951000100010002037203711100110000000073116111786100020382038203820382038
100420371500000006116862510001000100026452112018203720371571318951000100010002037203711100110000000073116111786100020382038203820382038
100420371500000006116862510001000100026452112018203720371571318951000100010002037203711100110000000073124111786100020382038203820382038
1004203715000008806116862510001000100026452112018203720371571318951000100010002037203711100110000000073116111786100020382038203820382038

Test 2: Latency 1->2

Code:

  sxtl2 v0.8h, v0.16b
  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)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 access (a0)l1d 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
102042003715000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715000000611968646101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
1020420037150000002161968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038
102042003715000000611968625101001001000010010000500284752112001820037200371842131874510100200100002001000020037200371110201100991001001000010000000071011611197910100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire uop (01)cycle (02)03mmu table walk instruction (07)mmu table walk data (08)0918191e1f3f4e51schedule 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)acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002420037150000002406119686251001012100001210000502847521120018200372003718443318767100122010000201000020037200371110021109101010000100006442162219786010000102003820038200382003820038
100242003715000000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100006402162219786010000102003820038200382003820038
100242003715000000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100006402162219786010000102003820038200382003820038
100242003715010000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100006402162219786010000102003820038200382003820038
100242003715000000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100006402162219786010000102003820038200382003820038
100242003715000000006119686251001010100001210000602847521120018200372003718443318767100102010000201000020037200371110021109101010000100006402162219786010000102003820038200382003820038
1002420037150000003006119686251001212100001210000602850049120018200372003718443318767100102010000201000020037200371110021109101010000100006402162219786010000102003820038200382003820038
100242003715000000006119686251001010100001010000502847521120018200372003718443318767100122010000201000020037200371110021109101010000100006402162219786010000102003820038200382003820038
100242003715000000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100006403162219786210000102003820038200382003820038
100242003715000000006119686251001010100001010000502847521120018200372003718443318767100102010000201000020037200371110021109101010000100006402162219786010000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  sxtl2 v0.8h, v8.16b
  sxtl2 v1.8h, v8.16b
  sxtl2 v2.8h, v8.16b
  sxtl2 v3.8h, v8.16b
  sxtl2 v4.8h, v8.16b
  sxtl2 v5.8h, v8.16b
  sxtl2 v6.8h, v8.16b
  sxtl2 v7.8h, v8.16b
  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 instruction (07)l2 tlb miss instruction (0a)181e1f3f51schedule 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)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)9fbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
802042005715011000292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151182161120035800001002003920039200392003920039
802042003815011000292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039
802042003815011000292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039
80204200381501101620292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039
802042003815011000292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039
8020420038150110150292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039
802042003815011090292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039
802042003815011090292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039
802042003815011000292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039
802042003815011000292580108100800081008002050064013220019200382003899776998980120200800322008003220038200381180201100991001008000010011151181161120035800001002003920039200392003920039

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03mmu table walk instruction (07)mmu 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 cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200391500000000392580010108000010800005064000002001920038200389996310018800102080000208000020038200381180021109101080000100005020716362003580000102003920039200392003920039
80024200381500000090392580010108000010800005064000002001920038200389996310018800102080000208000020038200381180021109101080000100005020216622003580000102003920039200392003920039
80024200381490000000392580010108000010800005064000012001920038200389996310018801242080000208000020038200381180021109101080000100005020616262003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000002001920038200389996310018800102080000208000020038200381180021109101080000100005020216262003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000012001920038200389996310018800102080000208000020038200381180021109101080000100005020316622003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000002001920038200389996310018800102080000208000020038200381180021109101080000100005020216222003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000012001920038200389996310018800102080000208000020038200381180021109101080000100005020216222003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000002001920038200389996310018800102080000208000020038200381180021109101080000100005020216222003580000102003920039200392003920039
80024200381500000000392580010108000010800005064000012001920038200389996310018800102080000208000020038200381180021109101080000100005020216232003580000102003920039200392003920039
80024200381500000000672580010108000010800005064000012001920038200389996310018800102080000208000020038200381180021109101080000100005020616262003580000102003920039200392003920039