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 (8H)

Test 1: uops

Code:

  xtn v0.8b, 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)0309l2 tlb miss data (0b)1e1f3f4e51schedule uop (52)schedule simd uop (54)dispatch simd uop (57)ldst uops in schedulers (5b)696d6emap 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)l1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
100420371500006116862510001000100026452120182037203715713189510001000100020372037111001100000000073216111786100020382038203820382038
100420371500006116862510001000100026452120182037203715713189510001000100020372037111001100000000073116111786100020382038203820382038
100420371500006116862510001000100026452120182037203715713189510001000100020372037111001100000000073116111786100020382038203820382038
1004203715000014516862510001000100026452120182037203715713189510001000100020372037111001100000000073116111786100020382038203820382038
100420371500006116752510001000115226452120542084208415758189911521169117020842037211001100000202198573116111786100020382074203820382038
100420371500006116862510001000100026452120182037203715713189510001000100020372037111001100000000073116111786100020382038203820382038
1004203715000034516862510001000100026452120182037203715717189510001000100020372037111001100000010073116111786100020382038203820382038
1004203715000012816862510001000100026452120182037208415713189510001000100020372037111001100000000073116111786100020382038203820382038
1004203715000010316862510001000100026452120182037203715713189510001000100020372037111001100010000073116111786100020382038203820382038
100420371600006116862510121000100026452120182037203715713189510001000100020372037111001100000000073116111786100020382038203820382038

Test 2: Latency 1->2

Code:

  xtn v0.8b, 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): 2.0037

retire uop (01)cycle (02)03mmu table walk data (08)09l2 tlb miss data (0b)18191e1f3a3f4e51schedule 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)a9acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)ea? simd retires (ee)? int retires (ef)f5f6f7f8fd
10204200371560000000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000000710116101979100100001002003820038200382003820038
10204200371610000000061196862510100100100001001000050028475211200182003720037184217187451027020010000200100002003720037111020110099100100100001000000000710116111979100100001002003820038200382003820038
10204200371550000000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000000710116111979100100001002003820038200382003820038
10204200371550000000061196862510100100100001001000050028475211200182003720037184213187451010020010000200101662003720085111020110099100100100001000000000710116111979101100001002003820038200382003820038
10204200371550000000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000000710116111979100100001002003820038200382003820038
10204200371560000000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000000710116111979100100001002003820038200382003820038
10204200371550000000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000000710116111979100100001002003820038200382003820038
10204200371550000000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000000710116111979100100001002003820038200382003820038
10204200371550000000061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000000710116111979100100001002003820038200382003820038
102042003715500000088061196862510100100100001001000050028475211200182003720037184213187451010020010000200100002003720037111020110099100100100001000000000710116111979100100001002003820038200382003820038

1000 unrolls and 10 iterations

Result (median cycles for code): 2.0037

retire uop (01)cycle (02)0318191e3a3f4e51schedule 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)9fl1d tlb access (a0)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002420037155000061196862510010101000010100005028475210200182003720037184430318786100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
1002420037156000061196862510010101000010100005028475210200182003720037184430318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
10024200371560012061196862510010101000010100005028475211200182003720037184430318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
1002420037155000061196862510010101000010100005028475210200182003720037184430318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
1002420037155000061196862510010101000010100005028475210200182003720037184430318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
100242003715500002678196862510010101000010100005028475210200182003720037184430318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
10024200371550000261196862510010101000010100005028475210200182003720037184430318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
1002420037155000061196862510010101000010100005028475210200182003720037184430318767100102010000201000020037200371110021109101010000100000036402162219786010000102003820038201812008620228
10024201791550000441196862510010101000010100005028475210200182003720037184430318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038
1002420037155000061196862510010101000010100005028475210200182003720037184430318767100102010000201000020037200371110021109101010000100000006402162219786010000102003820038200382003820038

Test 3: throughput

Count: 8

Code:

  xtn v0.8b, v8.8h
  xtn v1.8b, v8.8h
  xtn v2.8b, v8.8h
  xtn v3.8b, v8.8h
  xtn v4.8b, v8.8h
  xtn v5.8b, v8.8h
  xtn v6.8b, v8.8h
  xtn v7.8b, 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)03mmu table walk instruction (07)0918191e3f51schedule 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)a9acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8020420067155000007125801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000010011151181162120035800001002003920039200392003920039
8020420038155000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000011151182162220035800001002003920039200392003920039
8020420038155000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000011151182162120035800001002003920039200392003920039
8020420038156000002925801081008000810080020500640132120019200382003899776998980120200800322008003220038200381180201100991001008000010000000311151182162220035800001002003920039200392003920039
8020420038156000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000011151182162220035800001002003920039200392003920039
8020420038155000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000011151182162220035800001002003920039200392003920039
80204200381610000017325801081008000810080020500640132120019200382003899776998980120200800322008003220191201954180201100991001008000010000000011151182162220082800001002003920039200392003920093
80204200881550002029258048810080008100800205006401320200192003820038100126998980120200800322008003220038200381180201100991001008000010000010011151182162120035800001002003920039200392003920039
8020420038155000002925801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000010011151182161220035800001002003920039200392003920039
8020420038156000007125801081008000810080020500640132020019200382003899776998980120200800322008003220038200381180201100991001008000010000000011151182162220035800001002003920039200392003920039

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)09l2 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)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)9fl1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
800242005015600000003925800101080000108000050640000020019200382003899960310018800102080000208000020038200381180021109101080000100050201216672003580000102003920039200392003920039
80024200381560000000392580010108000010800005064000002001920038200389996031001880010208000020800002003820038118002110910108000010005020416652003580000102003920039200392003920039
80024200381550000000392580010108000010800005064000002001920038200389996031001880010208000020800002003820038118002110910108000010005020516562003580000102003920039200392003920039
800242003815600000003925800101080000108000050640000020019200382003899960310018801072080097208009820087200381180021109101080000100050206161162003580000102009820088200392009920047
800242003815510011174116120258019710800001080000506400001200192003820038999603100188001020800002080000200382003811800211091010800001003502051611102003580000102003920039200392003920039
80024200381550000000392580010108000010800005064000012001920038200389996031001880010208000020800002003820038118002110910108000010005020516662003580000102003920039200392003920039
80024200381550000000392580010108000010800005064000012001920038200389996031001880010208000020800002003820038118002110910108000010005020516352003580000102003920039200392003920039
80024200381550000000622580010108000010800005064076002001920038200389996031001880010208000020800002003820038118002110910108000010005020416662003580000102003920039200392003920039
800242003815500000003925800101080000108000050640000120019200382003899960310018800102080000208000020038200381180021109101080000100050204161152003580000102003920039200392003920039
800242003815500000003925800101080000108000050640000120019200382003899960310018800102080000208000020038200381180021109101080000100050201116952003580000102003920039200392003920039