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

FCVTL2 (vector, 4S)

Test 1: uops

Code:

  fcvtl2 v0.4s, 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)031e1f3f4e51schedule 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)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
1004303724120612547251000100010003981600301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
100430372400612547251000100010003981600301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
100430372400612547251000100010003981601301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
1004303724120822547251000100010003981600301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
100430372300612547251000100010003981600301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
100430372490612547251000100010003981601301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
100430372400612547251000100010003981600301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
1004303724120612547251000100010003981600301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
100430372300612547251000100010003981601301830373037241432895100010001000303730371110011000073116112629100030383038303830383038
100430372400612547251000100010003981601301830373037241432895100010001000303730371110011000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtl2 v0.4s, 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)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)ld unit uop (a6)st unit uop (a7)l1d cache writeback (a8)a9acafcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
102043003723300000061295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001000000000071011611296330100001003003830038300383003830038
102043003723200000061295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001000000000071011611296670100001003008730038300383003830038
102043003723200000061295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001000000000071011611296330100001003003830038300713003830038
102043003723300000061295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001004200209071011611296330100001003003830038300383003830038
1020430037233011014488240295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001000000000071011611296330100001003003830038300383003830038
102043003723300000061295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001000000300071011611296330100001003003830038300383003830038
102043003723200000061295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001000000000071011611296330100001003003830038300383003830038
102043003723300000061295472510100100100001001000050042771601300183003730037282643287451010020010000200100003003730037111020110099100100100001000000000071011611296330100001003003830038300383003830038
1020430037233000000103295472510100100100001251000050042771601300183003730037282643287451010020010172200100003003730037111020110099100100100001000000000071015011296330100001003003830038300383003830038
102043003723200001205782954725101001001000010010000500427716013001830037300372826432874510254200100002041000030037300373110201100991001001000010002400030710116232966914100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03l2 tlb miss data (0b)18191e1f3f4e5051schedule 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)9fld unit uop (a6)l1d cache writeback (a8)a9accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002430132233000660103295470251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000640424342970110000103003830038300383003830038
10024300372320003061295470251001010100001010000504277160130018300373008428286328767100102010000201000030037301311110021109101010000100000640416342962910000103003830038300383003830038
10024300372320000061295470251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000640416342962910000103003830038300383003830038
100243003723200000612954755251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000640416442962910000103003830038300383003830038
10024300372330000061295470251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000640416432962910000103003830038300383003830038
10024300372330000061295470251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000640316442962910000103003830038300383003830038
10024300372320000061295380251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000640416432962910000103003830038300383003830038
10024300372330000082295470251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000640416442962910000103003830038300383003830038
10024300372330000061295470251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100000640316342962910000103003830038300813008530038
100243003723300018061295470251001010100001010000504277160130018300373003728286328767100102010000201000030037300371110021109101010000100300640416342962910000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtl2 v0.4s, v8.8h
  fcvtl2 v1.4s, v8.8h
  fcvtl2 v2.4s, v8.8h
  fcvtl2 v3.4s, v8.8h
  fcvtl2 v4.4s, v8.8h
  fcvtl2 v5.4s, v8.8h
  fcvtl2 v6.4s, v8.8h
  fcvtl2 v7.4s, 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)03l1i tlb fill (04)mmu table walk data (08)18191e1f3a3f51schedule 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)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
802042009515500000025125801081008000810180130500643432020297204572045810044381012180836202807662008066820357204597180201100991001008000010040230654111524713941716203671800001002036520410204072041320355
802042035216401679247042256825801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000000111512231688200360800001002004020040200402004020040
802042003915500000025925801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000000111512281638200360800001002004020040200402004020040
8020420039155000012023125801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000000111512291688200360800001002004020040200402004020040
802042003915600000025625801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000000111512281688200360800001002004020040200402004020040
802042003916100000023525801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000000111512291698200360800001002004020040200402004020040
802042003915600000023525801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000000111512231689200360800001002004020040200402004020040
8020420039155000000222525801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010001000111512291699200360800001002004020040200402004020040
802042003915500000023525801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000000111512291699200360800001002004020040200402004020040
802042003915510000023525801081008000810080020500640132020020200392003999776999080120200800322008003220039200391180201100991001008000010000000111512291699200360800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)031e1f3a3f51schedule 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)ld unit uop (a6)l1d cache writeback (a8)a9accfd0l1i cache miss demand (d3)d5map dispatch bubble (d6)ddfetch restart (de)dfe0? simd retires (ee)? int retires (ef)f5f6f7f8fd
8002420051155000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010000005024004163442003680000102004020040200402004020040
8002420039155000402580106108000010800005064000001200202003920039999631001980010208000020800002003920039118002110910108000010001005024007164342003680000102004020040200402004020040
8002420039161000705258001010800001080000506400000120020200392003999963100198001020800002080000200392003911800211091010800001000001295024004164342003680000102004020040200402004020040
8002420039155000402580010108000010801055064082401200202003920039999631001980010208000020800002003920039118002110910108000010000065026007164642003680000102004020040200402004020040
800242003915601040402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010001005024304167642003680000102004020040200402004020040
8002420039155000402580010108000010800005064000001200202003920039999631001980010208000020800002003920039118002110910108000010000005024004164342003680000102004020040200402004020040
8002420039155000402580010108000010800005064000000200202008820039999631001980010208000020800002003920039118002110910108000010000005024004164752003680000102004020040200402004020040
8002420039156000402580010108000010800005064000001200202003920039999631001980010208000020800002003920039118002110910108000010003205024305323442003680000102004020040200402004020040
8002420039156000402580010108000010800005064000001200202003920039999631001980010208000020800002003920039118002110910108000010000005024034711164442003680000102004020040200402004020040
8002420039155000402580010108000010800005064000000200202003920039999631001980010208000020800002003920039118002110910108000010001035024004164442003680000102004020040200402004020040