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

FCVTNU (vector, 2S)

Test 1: uops

Code:

  fcvtnu v0.2s, v0.2s
  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)03mmu table walk data (08)1e3f4e51schedule 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
1004303724006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
10043037240010325472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303724006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
10043037230015625472510001000100039816013018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038
1004303723006125472510001000100039816003018303730372414328951000100010003037303711100110000073116112629100030383038303830383038

Test 2: Latency 1->2

Code:

  fcvtnu v0.2s, v0.2s
  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)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)e0ec? simd retires (ee)? int retires (ef)f5f6f7f8fd
10204300372320441295472510100100100001001000050042771600300183003730037282716287411010020010008200100083003730037111020110099100100100001000011171701611296330100001003003830038300383003830086
1020430037233061295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038
1020430037232061295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038
1020430037232061295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038
10204300372330318295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038
102043003723301539295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300863003830038
1020430037233061295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000010071011611296330100001003003830038300383003830038
1020430037241061295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038
10204300372320107295472510100100100001001000050042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296330100001003003830038300383003830038
1020430037233061295472510100100100001001014850042771600300183003730037282643287451010020010000200100003003730037111020110099100100100001000000071011611296331100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)03181e3f4e51schedule 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)daddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
1002430037233015612954725100101010000101000050427716003001830037300372828632877710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038
100243003722400612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038
100243003722400612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038
100243003722500612954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038
100243003722500612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038
100243003722500612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038
100243003723300612954725100101010000101000050427716013001830037300372828632876710010201000020100003003730037111002110910101000010006401240222962910000103003830038300383003830038
100243003722500612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038
100253003722500612954725100101010000101000050427716003001830037300372828632876710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038
100243003722500612954725100101010000101014950427716003001830037300372828632876710010201000020100003003730037111002110910101000010006402160222962910000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  fcvtnu v0.2s, v8.2s
  fcvtnu v1.2s, v8.2s
  fcvtnu v2.2s, v8.2s
  fcvtnu v3.2s, v8.2s
  fcvtnu v4.2s, v8.2s
  fcvtnu v5.2s, v8.2s
  fcvtnu v6.2s, v8.2s
  fcvtnu v7.2s, v8.2s
  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)0318191e1f3f51schedule 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)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)9fl1d tlb miss (a1)ld unit uop (a6)l1d cache writeback (a8)a9acbranch 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
8020420059155000030258010810080008100800205006401320200202003920039997706999080120200800322008003220039200391180201100991001008000010000000111511821600200360800001002004020040200402004020040
8020420039155000030258010810080008100800205006401320200202003920039997706999080120200800322008003220039200391180201100991001008000010000000111511801600200360800001002004020040200402004020040
8020420039155000072258010810080008100800205006401320200202003920039997706999080120200800322008003220039200391180201100991001008000010000000111511801601200360800001002004020040200402004020040
8020420039155400030258010810080008100800205006401320200202003920039997706999080120200800322008003220039200391180201100991001008000010000000111511801610200360800001002004020040200402004020040
8020420039155000030258010810080008100800205006401320200202003920039997706999080120200800322008003220039200393180201100991001008000010000000111511801600200360800001002004020040200402004020040
8020420039156000030258010810080008100800205006401320200202003920039997706999080120200800322008003220039200391180201100991001008000010000000111511801600200360800001002004020040200402004020040
8020420039155000030258010810080008100800205006401320200202003920039997706999080120200800322008003220039200391180201100991001008000010000000111511801600200360800001002004020040200402004020040
80204200391550039030258010810080008100800205006434480200202003920039997706999080120200800322008003220039200391180201100991001008000010000000111511801600200360800001002004020040200402004020040
802042003915600451321425258010810080008100800205006401320200202003920039997706999080120202800322008003220039200391180201100991001008000010000100111511801600200360800001002004020040200402004020040
80204200391550000695258010810080008100800205006401320200202003920039997706999080120200800322008003220039200391180201100991001008000010000000111511801600200360800001002004020040200402004020040

1000 unrolls and 10 iterations

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

retire uop (01)cycle (02)0309l2 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 cache writeback (a8)accfd0d2l1i cache miss demand (d3)d5map dispatch bubble (d6)d9ddfetch restart (de)e0eaeb? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200501550000514025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000502000016160616200360080000102004020040200402004020040
8002420039155000028840258001010800001080000506400000200202003920039999631001980010208000020800002003920039118002110910108000010005020000171601717200360080000102004020040200402004020040
8002420039156000104025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000502000017160176200360080000102004020040200402004020040
800242003915600003004025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000502000017160176200360080000102004020040200402004020040
800242003915600002974025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000502000017160178200360080000102004020040200402004020040
800242003915500002792302580010108000010800005064000002002020039200399996310019800102080000208000020039200391180021109101080000100050200008160617200360080000102004020040200402004020040
80024200391550000214025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000502000017160178200360080000102004020040200402004020040
800242003915600000402580010108000010800005064000002002020039200399996310019800102080000208000020039200391180021109101080000100050200006160177200360080000102004020040200402004020040
8002420039155000004025800101080000108000050640000020020200392003999963100198001020800002080000200392003911800211091010800001000502000017160157200360080000102004020040200402004020040
80024200391550000318402580010108000010800005064000002002020039200399996310019800102080000208000020039200391180021109101080000100050200006160176200360080000102004020040200402004020040