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

FRSQRTS (vector, 2S)

Test 1: uops

Code:

  frsqrts v0.2s, v0.2s, v1.2s
  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)031e3f4e51schedule 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
100440373106134072510001000100053190814018403740373258338951000100020004037403711100110000073216113473100040384038403840384038
100440373036134072510001000100053190804018403740373258338951000100020004037403711100110000073116113473100040384038403840384038
100440373008434072510001000100053190814018403740373258338951000100020004037403711100110000073116113473100040384038403840384038
100440373106134072510001000100053190814018403740373258338951000100020004037403711100110000073116113473100040384038403840384038
100440373006134072510001000100053190804018403740373258338951000100020004037403711100110000073116113473100040384038403840384038
100440373106134072510001000100053190814018403740373258338951000100020004037403711100110000073116113473100040384038403840384038
100440373066134072510001000100053190804018403740373258338951000100020004037403711100110000073116113473100040384038403840384038
100440373006134072510001000100053190804018403740373258338951000100020004037403711100110000073116113473100040384038403840384038
100440373006134072510001000100053190814018403740373258338951000100020004037403711100110000373116113473100040384038403840384038
100440373006134072510001000100053190814018403740373258338951000100020004037403711100110000073116113473100040384038403840384038

Test 2: Latency 1->2

Code:

  frsqrts v0.2s, v0.2s, v1.2s
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 4.0037

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)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)9fl1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? simd retires (ee)? int retires (ef)f5f6f7f8fd
102044003730007263940725101001001000010010000500570690840018400374003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038
10204400373000613940725101001001000010010000500570690840158400374003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038
10204400373000613940725101001001000010010000500570690840018400374003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038
10204400373000613940725101001001000010010000500570690840018400374003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038
10204400372990613940725101001001000010010000500570690840018400374003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038
10204400373000613940725101001001000010010000500570690840018400374003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038
10204400372990613940725101001001000010010000500570690840018400374003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038
10204400373000613940725101001001000010010000500570690840018400374003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038
10204400373000613940725101001001000010010000500570690840018400374003738108338745101002001000020020000400374003711102011009910010010000100207102162239479100001004003840038400384003840038
10204400373000613940725101001001000010010000500570690840018400774003738108338745101002001000020020000400374003711102011009910010010000100007102162239479100001004003840038400384003840038

1000 unrolls and 10 iterations

Result (median cycles for code): 4.0037

retire uop (01)cycle (02)03mmu table walk data (08)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)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)a9acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
100244003730000000061394072510010101000010100005057069081400184003740037381303387671001020100002020000400374003711100211091010100001000000006402162239473010000104003840038400384003840038
100244003729900000061394072510010101000010100005057069080400184003740037381303387671001020100002020000400374003711100211091010100001000000006402162239473010000104003840038400384003840038
100244003730000000061394072510010101000010100005057069080401584003740037381303387671001020100002020000400374003711100211091010100001000000006402162239473010000104003840038400854003840038
100244003730000000061394072510010101000010100005057069081400184003740037381303387671001020100002020000400374003711100211091010100001000000006402162239473010000104003840038400384003840038
100244003730000000061394072510010101000010100005057069080400184003740037381303387671001020100002020000400374003711100211091010100001000000006402162239473010000104003840038400384003840038
100244003731000090061394072510010101000012100005057069080400184003740037381303387671001020101722020000400374003721100211091010100001000000006402162239473010000104003840038400384003840038
100244003731000018008939407251001010100001010000505706908040018400374003738130283887511048201097222222644036840368811002110910101000010403022134007883654439711310000104003840038400384003840038
1002440037311000900823940725100101010000141000050572086804001840366400373813052387671001024100002021936403684003711100211091010100001000010306822162239914010000104003840038400384050940038
100244003731000090061394072510010101000010100005057069081400184003740037381303387671001020100002020000400374003711100211091010100001000000306402162239473010000104003840038400384003840085
10024400373140991188704061393982510010101000010100005057069080400184003740037381303387671001020100002020000400374003711100211091010100001000200006402162239473010000104003840038400384003840038

Test 3: Latency 1->3

Code:

  frsqrts v0.2s, v1.2s, 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): 4.0037

retire uop (01)cycle (02)03mmu table walk instruction (07)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)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)a9acc2cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
10204400373001000000072639407251010010010000100100005005706908040018400374003738108338745101002001000020020000400374003711102011009910010010000100000000071021622394790100001004003840038400384003840038
1020440037300000000006139407251010010010000100100005005706908040018400374003738108338745101002001000020020000400374003711102011009910010010000100000000071021622394790100001004003840038400384018140038
1020440037299000000006139407251010010010000100100005005706908040018400374003738108338745101002001000020020000400374003711102011009910010010000100000000071021622394790100001004003840038400384003840038
1020440037300000000006139407251010010010000100100005005706908040018400374003738108338745101002001000020020000400374003711102011009910010010000100000000071021622394790100001004003840038400384003840038
1020440037300000000006139407251010010010000100100005005706908040018400374003738108338745101002001000020020000400374003711102011009910010010000100000100071021622394790100001004003840038400384003840038
1020440037299000000006139407251010010010000100100005005706908040018400374003738108338745101002001000020020000400374003711102011009910010010000100000000071021622394790100001004003840038400384003840038
1020440037300000000006139407251010010010000100100005005706908040018400374003738108338745101002001000020020000400374003711102011009910010010000100000000071021622394790100001004003840038400384003840038
1020440037299000000006139407251010010010000100100005005706908040018400374003738108338745101002001000020020664400374003711102011009910010010000100000300071041622394790100001004003840038400384003840038
10204400373000000000025139407251010010010000100100005005708304140018400374003738108338745101002001000020020000400374003711102011009910010010000100000000071021622394790100001004003840038400384003840038
1020440037299000000006139407251010010010000100100005005706908040018400374003738108338745101002001000020020662400374003711102011009910010010000100000000071021622394790100001004003840038400384003840038

1000 unrolls and 10 iterations

Result (median cycles for code): 4.0037

retire uop (01)cycle (02)03mmu table walk data (08)l2 tlb miss data (0b)181e1f3a3f4e51schedule 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)9fl1d tlb access (a0)l1d tlb miss (a1)ld unit uop (a6)st unit uop (a7)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
100244003730000000061394072510010101000010100005557069084001840037400373813033876710010201000020200004003740037111002110910101000010000003653016402162239473010000104003840038400384003840038
100244003730000000061394072510010101000010100005057069084001840037400373813033876710010201000020200004003740037111002110910101000010000000006402162239473010000104003840038400384003840038
1002440037299000000613940725100101010000101000050570690840018400374003738130338767100102010000202000040037400371110021109101010000100000018006402162239473010000104003840038400384003840038
1002440037299000000613940725100101010000101000050570690840018400374003738130338767100102010000202000040037400371110021109101010000100000096006402162239473010000104003840038400384003840038
1002440037300000000613940725100101010000101000050570690840018400374003738130338767100102010000202000040037400371110021109101010000100000072006402162239473010000104003840038400384003840038
1002440037300000000613940725100101010000101000050570690840018400374003738130338767100102010000202000040037400371110021109101010000100000078006402162239473010000104003840038400384003840038
1002440037300000000613940725100101010000101000050570690840018400374003738130338767100102010000202000040037400371110021109101010000100000087006402162239473010000104003840038400384003840038
10024400373000000006139407251001010100001010000505706908400184003740037381303387671001020100002020000400374003711100211091010100001000000144006402162239473010000104003840038400384003840038
1002440037299000000613940725100101010000101000050570690840018400374003738130338767100102010000202000040037400371110021109101010000100000024006402162239473010000104003840038400384003840038
100244003730000000061394072510010101000010100005057069084001840037400373813033876710010201000020200004003740037111002110910101000010000003006402162239473010000104003840038400384003840038

Test 4: throughput

Count: 8

Code:

  frsqrts v0.2s, v8.2s, v9.2s
  frsqrts v1.2s, v8.2s, v9.2s
  frsqrts v2.2s, v8.2s, v9.2s
  frsqrts v3.2s, v8.2s, v9.2s
  frsqrts v4.2s, v8.2s, v9.2s
  frsqrts v5.2s, v8.2s, v9.2s
  frsqrts v6.2s, v8.2s, v9.2s
  frsqrts v7.2s, v8.2s, v9.2s
  movi v8.16b, 9
  movi v9.16b, 10

(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)696d6emap 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)9fld unit uop (a6)l1d cache writeback (a8)accdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
802042005815004225801001008000010080000500640000200212004020040997303999880100200800002001600002004020040118020110099100100800001000000511021611200370800001002004120041200412004120041
8020420040150033025801001008000010080000500640000200212004020040997303999880100200800002001600002004020040118020110099100100800001000030511011611200370800001002004120041200412004120041
802042004015004225801001008000010080000500640000200212004020040997373999880100200800002001600002004020040118020110099100100800001000330511011611200370800001002009220041200412004120041
8020420040150042258010010080000100800005006400002002120040200409973039998801002008000020016000020040200401180201100991001008000010000120511011611200370800001002004120041200412004120041
8020420040150023225801001008000010080000500640000200212004020040997303999880100200800002001600002004020040118020110099100100800001000000511011611200370800001002004120041200412004120041
802042004015504225801001008000010080000500640000200212004020040997303999880100200800002001600002004020040118020110099100100800001000000511011611200370800001002004120041200412004120041
802042004015004725801001008000010080000500640000201812004020040997303999880100200800002001600002004020040118020110099100100800001000000513011611200370800001002004120041200412004120041
802042004015004725801001008000010080000500640000200212004020040997303999880100200800002001603002004020040118020110099100100800001000230511011611200370800001002004120041200412004120041
802042004015004225801001008000010080000500640000200212004020040997303999880100200800002001600002004020040118020110099100100800001000000511011611200370800001002004120041200412004120041
802042004015004225801001008000010080000500640000200212004020040997303999880100200800002001600002004020040118020110099100100800001000030511011611200370800001002004120041200412004120041

1000 unrolls and 10 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 cache writeback (a8)acbranch cond mispred nonspec (c5)branch mispred nonspec (cb)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? simd retires (ee)? int retires (ef)f5f6f7f8fd
80024200491500412580010108000010800005064000012002120040200409996310020800102080000201600002004020040118002110910108000010000050201016171720037080000102004120041200412004120041
800242004015004125800101080000108000050640000120021200402004099963100208001020800002016000020040200401180021109101080000100000502081617820037080000102004120041200412004120041
8002420040150041258001010800001080000506400001200212004020040999631002080010208000020160000200402004011800211091010800001000005020171617620101080000102004120041200412004120041
800242004015004125800101080000108000050640000020021200402004099963100208001020800002016000020040200401180021109101080000102000502081681720037080000102004120041200412004120041
8002420040150041258001010800001080000506400001200212004020040999631002080010208000020160000200402004011800211091010800001000005020171617620037080000102004120041200412004120041
80024200401500412580010108000010800005064000002002120040200409996310020800102080000201600002004020040118002110910108000010100150201716171720037080000102004120041200412004120041
8002420040150041258001010800001080000506400000200212004020040999631002080010208000020160000200402004011800211091010800001000005020171617820037080000102004120041200412004120041
800242004015004125800101080000108000050640000020021200402004099963100208001020800002016000020040200401180021109101080000100000502081617620037080000102004120041200412004120041
8002420040150041258001010800001080000506400000200212004020040999631002080010208000020160000200402004011800211091010800001000005020171617620037080000102004120041200412004120041
800242004015004125800101080000108000050640000020021200402004099963100208001020800002016000020040200401180021109101080000101230050201716171720037080000102004120041200412004120041