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

CNEG (32-bit)

Test 1: uops

Code:

  cneg w0, w0, hi
  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)
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000
100410301001100110002560310001000300010011000

Test 2: Latency 1->2

Code:

  cneg w0, w0, hi
  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)
10204100301010110101101082594161010710214302421000110100
10204100301010110101101072594351010710214302361000110100
10204100301010110101101072595391010710212302361000110100
10204100301010110101101072595391010710212302361000110100
10204100301010110101101072595391010710212302361000110100
10204100301010110101101072595391010710212302361000110100
10204100301010110101101072595391010710212302361000110100
10204100301010110101101072595391010710212302361000110100
10204100301010110101101072595391010710212302361000110100
10204100301010110101101072595391010710212302361000110100

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)
10024100301002110021100282595281003010038300201001110010
10024100301002110021100202595911002010020300201001110010
10024100301002110021100202595911002010020300201001110010
10024100301002110021100202595911002010020300201001110010
10024100301002110021100202595911002010020300201001110010
10024100301002110021100202595911002010020300201001110010
10024100301002110021100202595911002010020300201001110010
10024100301002110021100202595911002010020300201001110010
10024100301002110021100202595911002010020300201001110010
10024100301002110021100202595911002010020300201001110010

Test 3: Latency 1->3

Chain cycles: 1

Code:

  cneg w0, w1, hi
  tst x0, 1
  mov x0, 1
  mov x1, 2
  mov x2, 3

(non-fused SUB/CBNZ loop)

100 unrolls and 100 iterations

Result (median cycles for code, minus 1 chain cycle): 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)
20204200302020120201202095193392020920214402322010110100
20204200302020120201202085194482020820216402322010110100
20204200302020120201202095194482020820216402322010110100
20204200302020120201202085194482020820216402322010110100
20204200302020120201202085194482020820216402322010110100
20204200302020120201202085194482020820216402322010110100
20204200302020120201202085194482020820216402322010110100
20204200302020120201202085194482020820216402322010110100
20204200302020120201202085194482020820216402322010110100
20204200302020120201202085194482020820216402322010110100

1000 unrolls and 10 iterations

Result (median cycles for code, minus 1 chain cycle): 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)
20024200302002120021200295195912002020020400202001110010
20024200302002120021200205195912002020020400202001110010
20024200302002120021200205199092006020066400202001110010
20024200302002120021200205195912002020020400202001110010
20024200302002120021200205195912002020020400202001110010
20024200302002120021200205195912002020020400202001110010
20024200302002120021200205195912002020020400202001110010
20024200302002120021200205195912002020020400202001110010
20024200302002120021200205195912002020020400202001110010
20024200302002120021200205195912002020020400202001110010

Test 4: throughput

Count: 8

Code:

  cneg w0, w8, hi
  cneg w1, w8, hi
  cneg w2, w8, hi
  cneg w3, w8, hi
  cneg w4, w8, hi
  cneg w5, w8, hi
  cneg w6, w8, hi
  cneg w7, w8, hi
  mov x8, 9

(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)
802042688380115801158012029270280120802242402728001580100
802042675580115801158012029323680120802242402728001580100
802042674980115801158012029323680120802242402728001580100
802042673780115801158012029323680120802242402728001580100
802042673780115801158012029323680120802242402728001580100
802042673780115801158012029323680120802242402728001580100
802042673780115801158012029323680120802242402728001580100
802052676880158801588017426679580119802222402728001580100
802042673780115801158012029323680120802242402728001580100
802042673780115801158012029323680120802242402728001580100

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)
800242791980038800388005228287780048800522400208001180010
800242679780021800218002038943780020800202400208001180010
800242672980021800218002038943780020800202400208001180010
800242672280021800218002038943780020800202400208001180010
800242672280021800218002038943780020800202400208001180010
800242672280021800218002038943780020800202400208001180010
800242672280021800218002038943780020800202400208001180010
800242672280021800218002038943780020800202400208001180010
800252677180080800808010338943780020800202400208001180010
800242672980021800218002038943780020800202400208001180010