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

SUB (uxtx, 64-bit)

Test 1: uops

Code:

  sub x0, x0, x1, uxtx
  mov x0, 1
  mov x1, 2

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 1.000

Issues: 1.000

Integer unit issues: 1.001

Load/store unit issues: 0.000

SIMD/FP unit issues: 0.000

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)dispatch uop (78)map int uop (7c)map int uop inputs (7f)? int output thing (e9)? int retires (ef)
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000
100410301001100110002560310001000200010011000

Test 2: Latency 1->2

Code:

  sub x0, x0, x1, uxtx
  mov x0, 1
  mov x1, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 1.0030

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)dispatch uop (78)map int uop (7c)map int uop inputs (7f)map ldst uop inputs (80)map simd uop inputs (81)? int output thing (e9)? ldst retires (ed)? simd retires (ee)? int retires (ef)
102041003010101101011010825941610107102142022800100010010100
102041003010101101011010725953910107102122022400100010010100
102041003010101101011010725953910107102122022400100010010100
102041003010101101011010725953910107102122022400100010010100
102041003010101101011010725953910107102122022400100010010100
102041003010101101011010725953910107102122022400100010010100
102041003010101101011010725953910107102122022400100010010100
102041003010101101011010725953910107102122022400100010010100
102041003010101101011010725953910107102122022400100010010100
102041003010101101011010725953910107102122022400100010010100

1000 unrolls and 10 iterations

Result (median cycles for code): 1.0030

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)dispatch uop (78)map int uop (7c)map int uop inputs (7f)? int output thing (e9)? int retires (ef)
10024100301002110021100292594741002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010

Test 3: Latency 1->3

Code:

  sub x0, x1, x0, uxtx
  mov x0, 1
  mov x1, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 1.0030

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)dispatch uop (78)map int uop (7c)map int uop inputs (7f)? int output thing (e9)? int retires (ef)
10204100301010110101101072594331010710214202281000110100
10204100301010110101101072595391010710212202241000110100
10204100301010110101101072595391010710212202241000110100
10204100301010110101101072595391010710212202241000110100
10204100301010110101101072595391010710212202241000110100
10204100301010110101101072595391010710212202241000110100
10204100301010110101101072595391010710212202241000110100
10204100301010110101101072595391010710212202241000110100
10204100301010110101101072595391010710212202241000110100
10204100301010110101101072595391010710212202241000110100

1000 unrolls and 10 iterations

Result (median cycles for code): 1.0030

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)dispatch uop (78)map int uop (7c)map int uop inputs (7f)? int output thing (e9)? int retires (ef)
10024100301002110021100282594901002810034200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010
10024100301002110021100202595911002010020200201001110010

Test 4: throughput

Count: 8

Code:

  sub x0, x8, x9, uxtx
  sub x1, x8, x9, uxtx
  sub x2, x8, x9, uxtx
  sub x3, x8, x9, uxtx
  sub x4, x8, x9, uxtx
  sub x5, x8, x9, uxtx
  sub x6, x8, x9, uxtx
  sub x7, x8, x9, uxtx
  mov x8, 9
  mov x9, 10

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.3342

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)dispatch uop (78)map int uop (7c)map int uop inputs (7f)? int output thing (e9)? int retires (ef)
802042691080115801158012024036080120802221602448001580100
802042674080114801148011924036080120802241602488001580100
802042673780115801158012024036080120802241602488001580100
802042673780115801158012024036080120802241602488001580100
802042673780115801158012024036080120802241602488001580100
802042673780115801158012024036080120802241602488001580100
802042673780115801158012024036080120802221602448001580100
802042686780115801158012024036080120802221602488001580100
802042673780115801158012024036080120802241603528005780100
802042673780115801158012024036080120802241602488001580100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.3340

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)dispatch int uop (56)int uops in schedulers (59)dispatch uop (78)map int uop (7c)map int uop inputs (7f)? int output thing (e9)? int retires (ef)
800242793380039800398004426147780042800461600728002980010
800242683380021800218002027207180020800201600208001180010
800242672280021800218002028273880020800201600208001180010
800242671780021800218002028273880020800201601868007080010
800242673080021800218002028273880020800201600208001180010
800242671780021800218002028273880020800201600208001180010
800242672480021800218002028273880020800201600208001180010
800242671780021800218002028273880020800201600208001180010
800242671780021800218002028273880020800201600208001180010
800242671780021800218002028273880020800201600208001180010