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

FCVTZS (scalar, fixed-point, H to H)

Test 1: uops

Code:

  fcvtzs h0, h0, #3
  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)03091e3f4e51schedule 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
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
10043037230126125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303721100110000073116112629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723008425472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtzs h0, h0, #3
  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)l2 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)st unit uop (a7)l1d cache writeback (a8)a9acb5c2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)eb? simd retires (ee)? int retires (ef)f5f6f7f8fd
102043003724210009000612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038
102043003723300009001602954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000300710116112963300100001003003830038300383003830038
10204300372330000900612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038
102043003723300003900612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038
1020430037233000024001032954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038
102043003723200002700612954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038
102043003723300002130018492954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038
10204300372330000000612954725101001001000010010000500427716003001830037300372826432874510100200101822001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038
102043003723300001200612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038
10204300372320100000612954725101001001000010010000500427716003001830037300372826432874510100200101822001000030037300371110201100991001001000010000000000710116112963300100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03mmu 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)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)acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10024300372330000540612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003723200002250612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010001006402162229629010000103003830038300383003830038
1002430037233000000612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
1002430037233000018907262954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003723300001290103295472510010101000015111578742893280302343041430456283154128915113642211324221132130462304515110021109101010000104402797508734972330065410000103040530546305613054730562
10024305102361111111452968103294392441010814100801111200764290680030378303633060228328532895611663201181622119033032230555121100211091010100001002014075286931043630027410000103056430556305563031230511
1002430608237000000612954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
1002430037242000011101942954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
100243003724101000011542954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038
10024300372320000960612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010000006402162229629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtzs h0, h8, #3
  fcvtzs h1, h8, #3
  fcvtzs h2, h8, #3
  fcvtzs h3, h8, #3
  fcvtzs h4, h8, #3
  fcvtzs h5, h8, #3
  fcvtzs h6, h8, #3
  fcvtzs h7, h8, #3
  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)0e18191e1f3f51schedule uop (52)schedule int uop (53)schedule simd uop (54)schedule ldst uop (55)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
8020420058155000001203025801081008000801008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000000111511801600200360800001002004020040200402004020040
802042003915500000005825801081008000801008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000000111511801600200360800001002004020040200402004020040
802042003915600000003025801081008000801008002050064013212002020039200399977699908012020080032200800322003920039118020110099100100800001000000000111511801600200360800001002004020040200402004020040
802042003915500000003025801081008000801008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000000111511801600200360800001002004020040200402004020040
802042003915500000303025801081008000801008002050064013212002020039200399977699908012020080032200800322003920039118020110099100100800001000000000111511801600200360800001002004020040200402004020040
802042003915500000003025801081008000801008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000000111511801600200360800001002004020040200402004020040
8020420039155000000030258010810080008010080020500640132020020200392003999776100198012020080032200800322003920039118020110099100100800001000000030111511801600200360800001002004020040200402004020040
802042003915600000003025801081008000801008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000000000111511801600200360800001002004020040200402004020040
802042003915500000003025801081008000801008002050064013212002020039200399977699908012020080032200800322003920039118020110099100100800001000000000111511801600200360800001002004020040200402004020040
802042003915500000003025801081008000801008002050064013202002020039200399977699908012020080032200800322003920039118020110099100100800001000005090111511801600200360800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)03l2 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)5f60696d6emap 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)inst ldst (9b)9fl1d cache writeback (a8)acc2cfd2d5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8002420039155033402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211091010800000100005020017161772003680000102004020040200402004020040
800242003915000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211091010800000100005020017161782003680000102004020040200402004020040
80024200391500032525800101080000108000050640000002002020039200399996031001980010208000020800002003920039118002110910108000001000050200171617172003680000102004020040200402004020040
80024200391500040258001010800001080000506400000020020200392003999960310019800102080000208000020039200391180021109101080000010000502007168172003680000102004020040200402004020040
800242003915000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211091010800000100045020017166172003680000102004020040200402004020040
80024200391500040258001010800001080000506400000020020200392003999960310019800102080000208000020039200391180021109101080000010000502006168172003680000102004020040200402004020040
80024200391500040258001010800001080000506400000020020200392003999960310019800102080000208000020039200391180021109101080000010000502008166172003680000102004020040200402004020040
800242003915000402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211091010800000101005020017168172003680000102004020040200402004020040
8002420039150204025800101080000108000050640000002002020039200399996031001980010208000020800002003920039118002110910108000001000050200171617142003680000102004020040200402004020040
800242003915020402580010108000010800005064000000200202003920039999603100198001020800002080000200392003911800211091010800000100005020017161772003680000102004020040200402004020040