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

FCVTAU (scalar, D to D)

Test 1: uops

Code:

  fcvtau d0, d0
  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
100430372406125472510001000100039816003018303730372414328951000100010003037303711100110000073316222629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073316332629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073316332629100030383038303830383038
100430372306125472510001000100039816013018303730372414328951000100010003037303711100110000373316332629100030383038303830383038
1004303724126125472510001000100039816013018303730372414328951000100010003037303711100110000073316332629100030383038303830383038
100430372406125472510001000100039816013018303730372414328951000100010003037303711100110001073316332629100030383038303830383038
100430372306125472510001000100039816003018303730372414328951000100010003037303711100110000073316332629100030383038303830383038
100430372406125472510001000100039816003018303730372414328951000100010003037303711100110000073316332629100030383038303830383038
100430372406125472510001000100039816013018303730372414328951000100010003037303711100110000073316332629100030383038303830383038
100430372308425472510001000100039816013018303730372414328951000100010003037303711100110000073316332629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtau d0, d0
  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)03mmu table walk instruction (07)mmu table walk data (08)l2 tlb miss instruction (0a)l2 tlb miss data (0b)18191e1f243f4e51schedule 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)9fl1d tlb access (a0)l1d tlb miss (a1)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9acc2cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1020430037233000000120061295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000171011611296330100001003003830038300383003830038
102043003723300000000089295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300383003830038
102043003723200000000061295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300873003830038
1020430037232000000000726295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300383003830038
102043008023300000000061295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300383003830038
102043003723300000000061295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300383003830038
102043003723300000000061295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300383003830038
102043003723300000000061295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300383003830038
102043003723200000000061295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300383003830038
102043003723200000000061295472510100100100001001000050042771603001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000071011611296330100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03091e3f4e51schedule 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)9fl1d cache writeback (a8)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10024300372240961295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038
100243003722503661295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038
10024300372320061295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038
10024300372250661295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038
100243003722401561295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038
10024300372250361295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038
100243003722501861295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038
10024300372250061295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629210000103003830038300383003830038
100253003722505161295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038
100243003722501861295472510010101000010100005042771603001830037300372828632876710010201000020100003003730037111002110910101000010006402162229629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtau d0, d8
  fcvtau d1, d8
  fcvtau d2, d8
  fcvtau d3, d8
  fcvtau d4, d8
  fcvtau d5, d8
  fcvtau d6, d8
  fcvtau d7, d8
  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)191e3f51schedule 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
8020420061155000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151181160020036800001002004020040200402004020040
8020420039155009302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010007211151180160020036800001002004020040200402004020040
8020420039155003302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
802042003915600058258010810080008100800205006401320200202003920039997769990801202008003220080032200392003911802011009910010080000100013511151180160020036800001002004020040200402004020040
8020420039155000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
8020420039156000582580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
8020420039156000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402004020040
80204200391550003025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010001511151180160020036800001002004020040200402004020040
8020420039155000302580108100800081008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000011151180160020036800001002004020040200402011520040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03l2 tlb miss data (0b)18191e3f51schedule 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)ld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
800242003915500008225800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000005020516342003680000102004020040200402004020040
800242003915500006825800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000005020416442003680000102004020040200402004020040
800242003915500004025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000105020416432003680000102004020040200402004020040
8002420039155100095225800101080000108000050640000120020200392003999966100198001020800002080000201562015411800211091010800001003005020316442003680000102004020040200402004020040
800242014015600004025800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000005020416342003680000102004020040200402004020040
800242003915500004025800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000105020416342003680000102004020040200402004020040
800242003915500004025800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000105020416442003680000102004020040200402004020040
800242003915500008225800101080000108000050640000020020200392003999963100198001020800002080000200892009211800211091010800001000005020416342003680000102004020040200402004020040
800242003915500004025800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000105020316442003680000102004020040200402004020040
800242003915500008325800101080000108000050640000120020200392003999963100198001020800002080000200392003911800211091010800001000035020416432003680000102004020040200402004020040