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

LSR (immediate, 64-bit)

Test 1: uops

Code:

  lsr x0, x0, #17
  mov x0, 1
  mov x1, 2

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 1.000

Issues: 1.000

Integer unit issues: 1.000

Load/store unit issues: 0.000

SIMD/FP unit issues: 0.000

retire uop (01)cycle (02)031e3f4d51schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)606d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map int uop inputs (7f)8283flush restart other nonspec (84)85inst all (8c)inst int alu (97)l1d cache writeback (a8)cfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? int retires (ef)f5f6f7f8fd
100410357061862251000100010001691611035103572838681000100010001035411110011000173141119371000100010361036103610361036
100410358061862251000100010001691601035103572838681000100010001035411110011000073141129371000100010361036103610361036
100410358061862251000100010001691601035103572838681000100010001035411110011000073141119371000100010361036103610361036
1004103580105862251000100010001691601035103572838681153100010001035411110011000173141119371000100010361036103610361036
100410357061862251000100010001691601035103572938681000100011761035411110011000073141119371000100010361036103610361036
100410358061862251000100010001691601035103572838681000100010001035411110011000073141119371000100010361036103610361036
100410357061862251000100010001691601035103572838681000100010001035411110011000073141119371000100010361036103610361036
100410358061862251000100010001691101035103572838681000100010001035411110011000073141119371000100010361036103610361036
100410358061862251000100010001691601035103572838681000100010001035411110011000073141119371000100010361036103610361036
100410358061862251000100010001691601035103572838681000100010001035431110011000073141119371000100010361036103610361036

Test 2: Latency 1->2

Code:

  lsr x0, x0, #17
  mov x0, 1
  mov x1, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 1.0035

retire uop (01)cycle (02)031e3f4d51schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)60696a6d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map int uop inputs (7f)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)9fl1d tlb miss (a1)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? int retires (ef)f5f6f7f8fd
1020410035750619877251010010100101008866404969551003510035858038722101001020010200100354111102011009910010100100001271013711994110000101001003610036100361003610036
102041003575061987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010000071013711994110000101001003610036100361003610036
1020410035755461987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010000071013711994110000101001003610036100361003610036
102041003575061987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010000071013711994110000101001003610036100361003610036
102041003575061987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010000071013711994110000101001003610036100361003610036
102041003575061987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010000671013711994110000101001003610036100361003610036
102041003575061987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010000071013711994110000101001003610036100361003610036
1020410035756441987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010000071013711994110000101001003610036100361003610036
102041003575061987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010000071013711994110000101001003610036100361003610036
102041003575061987725101001010010100886640496955100351003585803872210100102001020010035411110201100991001010010001371013711994110000101001003610036100361003610036

1000 unrolls and 10 iterations

Result (median cycles for code): 1.0035

retire uop (01)cycle (02)0309181e1f3f4d51schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)696a6d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map int uop inputs (7f)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)9fl1d tlb access (a0)ld unit uop (a6)l1d cache writeback (a8)accfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? int retires (ef)f5f6f7f8fd
10024100357500006198632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
10024100357500006198632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
10024100357500006198632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
10024100357500006198632510010100101001088784496955100351003586023876210010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
10024100357500006198632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
10024100357500006198632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
10024100357500006198632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
100241003575000053698632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
10024100357500006198632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036
10024100357500006198632510010100101001088784496955100351003586023874010010100201002010035411110021109101001010000064024122994010000100101003610036100361003610036

Test 3: throughput

Count: 8

Code:

  lsr x0, x8, #17
  lsr x1, x8, #17
  lsr x2, x8, #17
  lsr x3, x8, #17
  lsr x4, x8, #17
  lsr x5, x8, #17
  lsr x6, x8, #17
  lsr x7, x8, #17
  mov x8, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.1675

retire uop (01)cycle (02)03181e3f51schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)60696a6d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map int uop inputs (7f)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)9fl1d tlb miss (a1)l1d cache writeback (a8)acc2branch cond mispred nonspec (c5)branch mispred nonspec (cb)cdcfd5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? int retires (ef)f5f6f7f8fd
802041341710800282780136801368014840071004910310133901339033266333680148802648026413390391180201100991008010010000901115120216121338780036801001339113391133911339113391
80204133901000198282780136801368014840071004910310133901339033266333680148802648026413390391180201100991008010010000001115120116221338780036801001339113391133911339113391
8020413390100005032780136801368014840071004910310133901339033266333680148802648026413390391180201100991008010010000001115120216221338780036801001339113391133911339113391
802041339010100282780136801368014840071004910310133901339033266333680148802648026413390391180201100991008010010000001115120116121338780036801001339113391133911339113391
802041339010000282780136801368014840071004910310133901339033266333680148802648026413390391180201100991008010010000301115120216121338780036801001339113391133911339113391
802041339010000282780136801368014840071014910310133901339033266333680148802648026413390391180201100991008010010000001115120216211338780036801001339113391133911339113391
802041339010000282780136801368014840071004910310133901339033266333680148802648026413390391180201100991008010010000001115120116121338780036801001339113391133911339113391
802041339010003282780136801368014840071004910310133901339033266333680148802648026413390391180201100991008010010000001115120216211338780036801001339113391133911339113391
802041339010000282780136801368014840071004910310133901339033266333680148802648026413390391180201100991008010010000001115120216221338780036801001339113391133911339113391
8020413390100002827801368013680148400710149103101339013390332663336801488026480264133903911802011009910080100100015101115120216121338780036801001339113391133911339113391

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.1671

retire uop (01)cycle (02)03181e1f3f51schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)696a6d6emap stall dispatch (70)map rewind (75)map stall (76)dispatch uop (78)map int uop (7c)map int uop inputs (7f)8283flush restart other nonspec (84)85inst all (8c)inst branch (8d)inst branch taken (90)inst branch cond (94)inst int alu (97)9fl1d tlb miss (a1)l1d cache writeback (a8)branch mispred nonspec (cb)cfd0d5map dispatch bubble (d6)ddfetch restart (de)e0? int output thing (e9)? int retires (ef)f5f6f7f8fd
8002413376101000352580010800108001040005049102911337113371333033348800108002080020133713911800211091080010100005022016196171336880000800101337213372133721337213372
800241337110000035258001080010800104000504910291133711337133303334880010800208002013371391180021109108001010010502806191781336880000800101337213372133721337213372
80024133711000003525800108001080010400050491029113371133713330333488001080020800201337139118002110910800101000050230171917171336880000800101337213372133721337213372
800241337110000035258001080010800104000504910291133711337133303334880010800208002013371391180021109108001010000502808197141336880000800101337213372133721337213372
8002413371100000352580010800108001040005049102911337113371333033348800108002080020133713911800211091080010100005027017191761336880000800101337213372133721337213372
8002413371100000352580010800108001040005049102911337113371333033348800108002080020133713911800211091080010100005028017198171336880000800101337213372133721337213372
800241337110000035258001080010800104000504910291133711337133303334880010800208028113371391180021109108001010000502806197171336880000800101337213434134331337213372
8002413371100000772580010800108001040005049102911337113371333033348800108002080020133713911800211091080010100305023017198171336880000800101337213372133721337213372
80024133711000003525800108001080010400050491029113371133713330333488001080020800201337139218002110910800101000050220171917171336880000800101337213372133721337213372
8002413371100000352580010800108001040005049102911337113371333033348800108002080020133713911800211091080010100005028017191481336880000800101337213372133721337213372