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

FCVTZU (vector, fixed-point, 8H)

Test 1: uops

Code:

  fcvtzu v0.8h, v0.8h, #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)03181e3f4e51schedule 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
1004303724006125472510001000100039816003018303730372414328951000100010003037303711100110000073316222629100030383038303830383038
1004303723007025472510001000100039816013018303730372414328951000100010003037303711100110000073216222629100030383038303830383038
1004303723006125472510001000100039816013018303730372414328951000100010003085303711100110000073216222629100030383038303830383038
1004303723006125472510001000100039816013018303730372414328951000100010003037303711100110000073216222629100030383038303830383038
10043037240010325472510001000100039816013018303730372414328951000100010003037303711100110000673216222629100030383038303830383038
10043037240010325472510001000100039816013018303730372414328951000100010003037303711100110000073216222629100030383038303830383038
1004303723006125472510001000100039816013018303730372414328951000100010003037303711100110001073216222629100030383038303830383038
1004303724006125472510001000100039816003018303730372414328951000100010003037303711100110000073216222629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110001073216222629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110000073216222629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtzu v0.8h, v0.8h, #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)031e3f4e51schedule 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)9fld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
10204300372330612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037211020110099100100100001000097101161129633100001003003830038300383003830038
10204300372330612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100001000137101161129633100001003003830038300383003830038
10204300372320612954725101001001000010010000500427716003001803003730037282643287451010020010000200100003003730037111020110099100100100001000067101161129633100001003003830038300383003830038
102043003723312612954725101001001000010010000500427716003001803003730037282643287451010020010000200100003003730037111020110099100100100001000107101161129633100001003003830038300383003830038
10204300372333842954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100001000067101161129705100001003003830038300383003830038
10204300372336612954725101001001000010010600500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100001000067101161129633100001003003830038300383003830038
10204300372330612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100001000067101161129633100001003003830038300383003830038
10204300372330612954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100001000067101161129633100001003003830038300383003830038
102043003723307262954725101001001000010010000500427716013001803003730037282643287451010020010000200100003003730037111020110099100100100001000007101161129633100001003003830038300383003830038
10204300372330892954725101001001000010010000500427716003001803003730037282643287451010020010000200100003003730037111020110099100100100001000067101161129633100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03mmu table walk instruction (07)1e3f4e51schedule 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)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002430037225006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100006402162229629010000103003830038300383003830038
1002430037225006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100306402162229631010000103003830038300383003830038
1002430037225006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100006402162229629010000103003830038300383003830038
1002430037225006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300372110021109101010000100006402162229629010000103003830038300383003830038
10024300372251306129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100006402162229629010000103003830038300383003830038
1002430037225008229547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100006402162229629010000103003830038300383003830038
1002430037225006129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100006402162229629010000103003830038300383003830038
10024300372250025129547251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100006402162229629010000103003830038300383003830038
1002430037225006129547251001012100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100006402162229629010000103003830038300383003830038
10024300372371017829547251001010100001010000604277160130018300373003728286328767100102010000201000030037300371110021109101010000100006402162229629010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtzu v0.8h, v8.8h, #3
  fcvtzu v1.8h, v8.8h, #3
  fcvtzu v2.8h, v8.8h, #3
  fcvtzu v3.8h, v8.8h, #3
  fcvtzu v4.8h, v8.8h, #3
  fcvtzu v5.8h, v8.8h, #3
  fcvtzu v6.8h, v8.8h, #3
  fcvtzu v7.8h, v8.8h, #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)031e3f51schedule 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)acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)dde0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8020420039156023025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
8020420039155011425801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915503025801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010002001115138016020036800001002004020040200402004020040
802042003915503025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
80204200391550100225801081008000810080020500640788120020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
8020420039156042725801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
8020420039155038725801081008000810080020500640132120020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020040
802042003915503025801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000101115118016020036800001002004020040200402004020040
8020420039155011425801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000101115118016020036800001002004020040200402004020040
8020420039155011525801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000001115118016020036800001002004020040200402004020088

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)l2 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)5f60696d6emap 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)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
800242003915500000612580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010002005020316242003680000102004020040200402004020040
800242003915500000822580010108000010804245064000011200202003920039999631001980010208000020800002003920039118002110910108000010426035020316442003680000102004020040200402004020040
8002420039155000004025800101080000108000050640000002002020039200399996310019800102080000208000020039200391180021109101080000100000365020416422003680000102004020040200402004020040
800242003915600000402580010108000010800005064000011200202003920039999631001980010208000020800002003920039118002110910108000010000065020216242003680000102004020040200402004020040
80024200391550000040258001010800001080000506400000020020200392003999963100198001020800002080000200392003911800211091010800001000001085020216522003680000102004020040200402004020040
800242003915500000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010000065020416522003680000102004020040200402004020040
800242003915600000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010000035020416422003680000102004020040200402004020040
8002420039155000004025800101080000108000050640000002002020039200399996310019800102080000208000020039200391180021109101080000100030005020316252003680000102004020040200402004020040
80024200391550000040258001010800001080000506400000020020200392003999963100198001020800002080000200392003911800211091010800001000280125020416432003680000102004020040200402004020040
8002420039155000004025800101080000108000050640000002002020039200399996310019800102080000208000020039200391180021109101080000100033065020216252003680000102004020040200402004020040