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

FCVTMS (vector, 8H)

Test 1: uops

Code:

  fcvtms 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)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
100430372306125472510001000100039816013018303730372414328951000100010003037303711100110000073216112629100030383038303830383038
100430372308525472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372606125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372308225472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372406125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372406125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100430372306125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
100530372406125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtms 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)03l1i tlb fill (04)mmu table walk data (08)l2 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)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)a9acbranch cond mispred nonspec (c5)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)ec? simd retires (ee)? int retires (ef)f5f6f7f8fd
1020430037233000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000710116112963300100001003003830038300383003830038
1020430037233000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000710116112963300100001003003830038300383003830038
1020430037232000000061295472510100100100001001000050042771600300180300723003728264328745101002001000020010000300373003711102011009910010010000100000000710116112963300100001003003830038300383003830038
10204300372330000012061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000710116112963300100001003003830038300383003830038
10204300372330000000612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100001000000018891972329957400100001003056030375305543037430328
1020430276237011118795880756629547251010010010000100100005004277160030270030371301322828937288721131323111165220111593036730275911020110099100100100001002204218330710116112963301100001003003830038300383003830038
10204300372330000000251295472510100100100001001000050042771601300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000710116112963300100001003003830038300383003830038
1020430037232000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100001000710116112963300100001003003830038300383003830038
1020430037233000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000710116112963300100001003003830038300383003830038
1020430037233000000061295472510100100100001001000050042771600300180300373003728264328745101002001000020010000300373003711102011009910010010000100000000710116112963300100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03mmu table walk data (08)09191e1f3f4e51schedule 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)st unit uop (a7)l1d cache writeback (a8)a9acc2branch mispred nonspec (cb)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10024300372250201806129547251001010100001010000504277160130018300843008328292328767100102010000201000030037300371110021109101010000100000000006402162229629010000103003830038300383003830038
1002430037224000006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000000006402162229629010000103003830038300383003830038
1002430037225000006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000000006402162229629010000103003830038300383003830038
1002430037225000006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000000006402162229629010000103003830038300383003830038
1002430037225000006129547251001010100001010000504277160030018300373003728286328767100102010000201000030037300371110021109101010000100000000006402162229629010000103003830038300383003830038
1002430037225000006129547251001010100001010000504277160130018300853003728286328767100102010000201000030037300371110021109101010000100000000006402162229629010000103003830038300383003830038
100243003722400000612954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010000037015006402162229629010000103003830038300383003830038
1002430037224000006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000000006402162229629010000103003830038300383003830038
1002430037225000006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000000006402162229629010000103003830038300383003830038
10024300372250000014529547441002110100001010000554277160130018300853013228286328767101612010000201000030037300371110021109101010000100600103206402162229629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtms v0.8h, v8.8h
  fcvtms v1.8h, v8.8h
  fcvtms v2.8h, v8.8h
  fcvtms v3.8h, v8.8h
  fcvtms v4.8h, v8.8h
  fcvtms v5.8h, v8.8h
  fcvtms v6.8h, v8.8h
  fcvtms 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)03mmu table walk instruction (07)l2 tlb miss instruction (0a)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)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? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
80204200491551003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010006111511811612200360800001002004020040200402004020040
802042003915513030258010810080008100800205006401320200202003920039997769990801202008003220080032200392003921802011009910010080000100133111511821611200360800001002004020040200402004020040
80204200391551303025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010003111511811611200360800001002004020040200402004020040
80204200391551303025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000111511811621201000800001002004020040200402004020040
80204200391561303025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010003111511811611200360800001002004020040200402004020040
802042003915513030258010810080008100800205006401320200202003920039997769990801202008003220080032200392003911802011009910010080000100196111511811611200361800001002004020040200402004020040
80204200391551103025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000111511811611200360800001002004020040200402004020040
80204200391551103025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000111511811611200360800001002004020040200402004020040
802042003915511030258010810080008100800205006401320200202003920039997769990801202008003220080032200392003911802011009910010080000100878111511811611200360800001002004020040200402004020040
80204200391551103025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010010111511811611200360800001002004020040200402004020040

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)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)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)acbranch mispred nonspec (cb)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8002420039155004025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000005020216112003680000102004020040200402004020040
80024200391550040258001010800001080000506400001200202003920039999631001980010208000020800002003920039118002110910108000010008705020116112003680000102004020040200402004020040
80024200391550040258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010208705020116112003680000102004020040200402004020040
80024200391550040258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010008405020116112003680000102004020040200402004020040
8002420039155003142580010108000010800005064000012002020039200399996310019800102080000208000020039200391180021109101080000100010805020116112003680000102004020040200402004020040
80025200391550040258001010800001080000506400001200202003920039999631001980010208000020800002003920039118002110910108000010009305020116112003680000102004020040200402004020040
80024200391550040258001010800001080000506400001200202003920039999631001980010208000020800002003920039118002110910108000010009005020116112003680000102004020040200402004020040
80024200391550040258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010007805020116212003680000102004020040200402004020040
8002420039156004025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000005020216222003680000102004020040200402004020040
800242003915500402580010108000010800005064000002002020039200399996310019800102080000208000020039200391180021109101080000100010505020116112003680000102004020040200402004020040