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

UCVTF (scalar, fixed-point, S from S)

Test 1: uops

Code:

  ucvtf s0, s0, #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)031e3f4e51schedule 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 cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
100430372308225472510001000100039816030183037303724143289510001000100030373037111001100000073216112629100030383038303830383038
100430372406125472510001000100039816030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
100430372406125472510001000100039816030183037303724143291410001000100030373037111001100000073216222629100030383038303830383038
100430372406125472510001000100039816030183037303724143289510001000100030373037111001100001073216222629100030383038303830383038
1004303724056025472510001000100039816030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
100430372406125472510001000100039816030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
100430372406125472510001000100039816030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
100430372306125472510001000100039816030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
1004303724047225472510001000100039816030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038
100430372406125472510001000100039816030183037303724143289510001000100030373037111001100000073216222629100030383038303830383038

Test 2: Latency 1->2

Code:

  ucvtf s0, s0, #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)03mmu table walk data (08)l2 tlb miss data (0b)18191e3f4e51schedule 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)acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
102043003723200000612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
102043003723200000612954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
102043003723300000612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
102043003723200000612954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
10204300372330000124412954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
102043003723200000612954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
102043003723200000612954725101001001000010010000500427716003001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
102043003723200000612954725101001001000011310000500427716003001830037300372826432874510100200100002021000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
102043003723300000612954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038
1020430037233000002512954725101001001000010010000500427716013001830037300372826432874510100200100002001000030037300371110201100991001001000010000000071021622296330100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)031e1f3f4e51schedule 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)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
100243003722500193295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
10024300372250082295472510010101000010100005042771602300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
100243003722500726295472510010101000010100005042771600300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
100243003722500726295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
100243003722500797295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
100243003722500612954725100101010000101000050427716013001830037300372828626287561001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
10024300372250061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
10024300372240061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
10024300372250061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038
10024300372250061295472510010101000010100005042771601300183003730037282863287671001020100002010000300373003711100211091010100001000640216222962910000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  ucvtf s0, s8, #3
  ucvtf s1, s8, #3
  ucvtf s2, s8, #3
  ucvtf s3, s8, #3
  ucvtf s4, s8, #3
  ucvtf s5, s8, #3
  ucvtf s6, s8, #3
  ucvtf s7, s8, #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)191e1f3f51schedule 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 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)dde0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
802042003915500000995258010810080008100800205006401320200200200392003999776999080120200800322008003220039200391180201100991001008000010000000011151180160200360800001002004020040200402004020143
8020420039155000917630258010810080008100800205006401320200200200392003999776999080120200800322008003220039200391180201100991001008000010000000011151530160200360800001002004020040200402004020040
802042003915500000410258010810080008100800205006401320200200200392003999776999080120200800322008003220039200391180201100991001008000010000000011151180160200360800001002004020040200402020620040
802042003915500000302580108100800081008002050064013202002002003920039100136999080120200800322008003220039200391180201100991001008000010000000011151180160200360800001002004020040200402004020040
80204200391550000030258018410080008100800205006401320200200200392003999776999080120200800322028003220039200391180201100991001008000010000000011151180160200360800001002004020040200402004020040
80204200391560000030258010810080008100800205006401320200200200392003999776999080120200802452008003220039200391180201100991001008000010000000011151180160200360800001002004020040200402004020040
80204200391550000030258010810080008100800205006401321200203200392003999776999080120200800322008003220039200391180201100991001008000010000000011151180160200360800001002004020040200402004020094
80204200391550000030258010810080008100800205006401321200200200392003999776999080120200800322008003220039200391180201100991001008000010000000011151180160200360800001002004020040200402004020040
80204200391550000030258010810080008100800205006401321200200200392003999776999080120200800322008003220039200391180201100991001008000010000000011151180160200360800001002004020040200402004020040
80204200391550003030258010810080008100800205006401320200200200392003999776999080335200800322008003220039200391180201100991001008000010000000611151180160200360800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)031e1f3f51schedule 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)9fld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200401550040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100105020216222003680000102004020040200402004020040
800242003915500141258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100005020316222003680000102004020040200402004020040
80024200391550040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100005020216322003680000102004020040200402004020040
80024200391560040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100005020216222003680000102004020040200402004020040
80024200391550040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100105020316222003680000102004020040200402004020040
80024200391550040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100005020216222003680000102004020040200402004020040
80024200391550040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100005020416322003680000102004020040200402004020040
80024200391550040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100005020316232003680000102004020040200402004020040
800242003915512040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100005020216232003680000102004020040200402004020040
80024200391550040258001010800001080000506400002002020039200399996310019800102080000208000020039200391180021109101080000100035020216222003680000102004020040200402004020040