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

URSQRTE (vector, 2S)

Test 1: uops

Code:

  ursqrte 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)03l1i tlb fill (04)191e3a3f4e51schedule 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)ld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)f5f6f7f8fd
100430372200026219002510001000100010445130183037303727383289510001000100030373037111001100000076416442919100030383038303830383038
100430372310026219002510001000100010445130183037303727383289510001000100030373037111001100000076416442919100030383038303830383038
100430372210026219002510001000100010445130183037303727383289510001000100030373037111001100000076416442919100030383038303830383038
100430372310026219002510001000100010461230183037303727383289510001000100030373037111001100000076416442919100030853038303830383038
100430372310026219002510001000100010445130183037303727383289510001000100030373037111001100000076416442919100030383038303830383038
1004303722100215719002510001000100010445130183037303727383289510001000100030373037111001100000076416442919100030383038303830383038
100430372310026219002510001000100010445130183037303727383289510001000100030373037111001100000076416442919100030383038303830383038
100430372310026219002510001000100010445130183037303727383289510001000100030373037111001100000076416442919100030383038303830383038
100430372310026219002510001000100010445130183037303727383289510001000100030373037111001100001076416442919100030383038303830383038
1004303723100246119002510001000100010445130183037303727383289510001000100030373037111001100000076416442919100030383038303830383038

Test 2: Latency 1->2

Code:

  ursqrte 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)03l1i tlb fill (04)mmu table walk data (08)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)6061696d6emap 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)acc2cfd0d2d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10204300372330000000061199002510100100100081001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
10204300372330000000061199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
10204300372330000000061199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
10204300372320000000061199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
10204300372330000000061199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
10204300372320000000061199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
10204300372330000000061199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
10204300372330000000061199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
10204300372330000000089199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038
1020430037242000002400061199002510100100100001001000050010674510030018300373003728588328745101002001000020010000300373003711102011009910010010000100000007100021622299190100001003003830038300383003830038

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0037

retire uop (01)cycle (02)030e1e3f4e51schedule 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)ld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10024300372320061199002510010101000010100005010674511300183003730037286103287671001020100002010000300373003711100211091010100001000006402162229919010000103003830038300383003830038
10024300372330061199002510010101000010100005010674511300183003730037286103287671001020100002010000300373003711100211091010100001000006402162229919010000103003830038300383003830038
10024300372330061199002510010101000010100005010674511300183003730037286103287671001020100002010000300373003711100211091010100001000036402162229919010000103003830038300383003830038
10024300372330061199002510010101000010100005010674511300183003730037286103287671001020100002010000300373003711100211091010100001020006402162229919010000103003830038300383003830038
100243003723201261199002510010101000010100005010674511300183003730037286103287671001020100002010000300373003711100211091010100001000006402162229919010000103003830038300383003830038
10024300372330061199002510010101000010100005010674511300183003730037286103287891001020100002010000300373003711100211091010100001000006402162229919010000103003830038300383003830038
10024300372330061199002510010101000010100005010674511300183003730037286123287671001020100002010000300373003711100211091010100001000036402162229919010000103003830038300383003830038
10024300372330061199002510010101000010100005010674510300183003730037286103287671001020100002010000300373003711100211091010100001000006402162229919010000103003830038300383003830038
10024300372330061199002510010101000010100005010674510300183003730037286103287671001020100002010000300373003711100211091010100001000106402162229919010000103003830038300383003830038
10024300372330061199002510010101000010100425010674510300183003730037286103287671001020100002010000300373003711100211091010100001000006402162229919010000103003830038300383003830038

Test 3: throughput

Count: 8

Code:

  ursqrte v0.2s, v8.2s
  ursqrte v1.2s, v8.2s
  ursqrte v2.2s, v8.2s
  ursqrte v3.2s, v8.2s
  ursqrte v4.2s, v8.2s
  ursqrte v5.2s, v8.2s
  ursqrte v6.2s, v8.2s
  ursqrte 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): 1.0005

retire uop (01)cycle (02)03mmu table walk data (08)1e1f3f51schedule 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)a9acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
802048004059900083625801001008000010080000500640000180020800398003969971669993801002008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040
802048003960000062625801001008000010080000500640000080020800398003969971669993801002008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040
802048003959900029325801001008000010080000500640000080020800398003969971669993801002008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040
8020480039599000487258010010080000100800005006400001800208003980039699716699938010020080008200800088003980039118020110099100100800001005600011151170160080036800001008004080040800408004080040
802048013759900021125801001008000010080000500640000080020800398003969971669993801002008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040
802048003960000039125801001008000010080000500640000180020800398003969971669993801002008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040
802048003959910050725801001008000010080000500640000180020800398003969971669993801002008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040
802048003959900049325801001008000010080000500640000080020800888003969971669993801352008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040
802048003960000040625801001008000010080000500640000180069800398003969971669993801002008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040
802048003960000038525801001008000010080000500640000080020800398003969971669993801002008000820080008800398003911802011009910010080000100000011151170160080036800001008004080040800408004080040

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 1.0005

retire uop (01)cycle (02)03l2 tlb miss data (0b)181e1f3f51schedule 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 miss (a1)ld unit uop (a6)l1d cache writeback (a8)acc2branch cond mispred nonspec (c5)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
800248004059900007152580010108000010800005064000001800208003980039699863700198001020800002080000800398003911800211091010800001000000050204163380034080000108004080040800408004080040
80024800395990000502580010108000010800005064000001800208003980039699863700198001020800002080000800398003911800211091010800001000000050209164380034080000108004080040800408004080040
80024800396000000502580010108000010800005064000001800208003980039699863700198001020800002080000800398003911800211091010800001000000050205165580034080000108004080040802378004080040
80024800396000000502580010108000010800005064000001800208003980039699863700198003220800002080000800398003911800211091010800001000600050205165580034080000108004080040800408004080236
80024800396000000502580010108000010800005064000001800208003980039699863700198001020800002080000800398003911800211091010800001000000050204165480034080000108004080040800408004080040
800248003959900001342580058108000010800005064000001800208003980039699863700198001020800002080000800398003911800211091010800001000100050204163380034080000108004080040800408004080040
80024800395990000502580010108000010800265064000001800208003980039699863700198001020800002080000800398003911800211091010800001000000050205164380034080000108004080040800408018880040
8002480039600025520502580010108000010800005064000001800208003980039699863700198001020800002080000800398003911800211091010800001000030150203163380034080000108004080040800408004080040
80024800395990000502580010108000010800005064000001800208003980039699863700198001020800002080000800398003911800211091010800001000000050207164580034080000108004080040800408004080040
80024800396000060715258001010800001080000506400000180020800398003969986197001980010208000020800008003980039118002110910108000010000150050204163380034080000108004080040800408004080090