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

FCMPE (scalar, S)

Test 1: uops

Code:

  fcmpe s0, s1
  mov x0, 1
  mov x1, 2
  mov x2, 3
  mov x3, 4

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 1.000

Issues: 1.000

Integer unit issues: 0.001

Load/store unit issues: 0.000

SIMD/FP unit issues: 1.000

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch simd uop (57)ldst uops in schedulers (5b)dispatch uop (78)map simd uop (7e)map simd uop inputs (81)? int output thing (e9)
10041034100111000100040001000100020001
10041034100111000100040001000100020001
10041034100111000100040001000100020001
10041034100111000100040001000100020001
10041034100111000100040001000100020001
10041034100111000100040001000100020001
10041034100111000100040001000100020001
10041034100111000100040001000100020001
10041034100111000100040001000100020001
10041034100111000100040001000100020001

Test 2: Latency 3->1

Chain cycles: 2

Code:

  fcmpe s0, s1
  fcsel d0, d2, d3, eq
  mov x0, 1
  mov x1, 2
  mov x2, 3
  mov x3, 4

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code, minus 2 chain cycles): 2.0033

retire uop (01)cycle (02)schedule 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)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
20204400332010110120000100200003001019248201002002000620050015110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000720050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100

1000 unrolls and 10 iterations

Result (median cycles for code, minus 2 chain cycles): 2.0033

retire uop (01)cycle (02)schedule uop (52)schedule int uop (53)schedule simd uop (54)dispatch int uop (56)dispatch simd uop (57)dispatch ldst uop (58)int uops in schedulers (59)simd uops in schedulers (5a)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map ldst uop (7d)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
20024400332001111200001020000030010192482001020020000205000011000010
20024400332001111200001020000030010192482001020020000205000011000010
20024400332001111200001020000030010192482001020020000205000011000010
20024400332001111200001020000030010192482001020020000205000011000010
20024400332001111200001020000030010192482001020020000205000011000010
20024400332001111200001020000030010195802004420020048205000011000010
20024400332001111200001020000030010192482001020020000205000011000010
20024400332001111200001020000030010192482001020020000205000011000010
20024400332001111200001020000030010192482001020020000205000011000010
20024400332001111200001020000030010192482001020020000205000011000010

Test 3: Latency 3->2

Chain cycles: 2

Code:

  fcmpe s0, s1
  fcsel d1, d2, d3, eq
  mov x0, 1
  mov x1, 2
  mov x2, 3
  mov x3, 4

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code, minus 2 chain cycles): 2.0033

retire uop (01)cycle (02)schedule 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)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
20204400332010110120000100200003001019248201002002000620050010110000100
20204400332010110120000100200003001019248201002002000620050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100
20204400332010110120000100200003001019248201002002000420050010110000100

1000 unrolls and 10 iterations

Result (median cycles for code, minus 2 chain cycles): 2.0033

retire uop (01)cycle (02)schedule 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)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
20024400332001111200001020000301019248200102020000205000011000010
20024400852002311200121020036301019248200102020000205000011000010
20024400332001111200001020000301019248200102020000205000011000010
20024400332001111200001020000301019248200102020000205000011000010
20024400332001111200001020000301019248200102020000205000011000010
20024400332001111200001020000301019248200102020000205000011000010
20024400332001111200001020000301019248200102020000205000011000010
20024400332001111200001020000301019248200102020000205000011000010
20024400842002311200121020036301019248200102020000205000011000010
20024400332001111200001020000301019248200102020000205000011000010

Test 4: throughput

Count: 8

Code:

  fcmpe s0, s1
  fcmpe s0, s1
  fcmpe s0, s1
  fcmpe s0, s1
  fcmpe s0, s1
  fcmpe s0, s1
  fcmpe s0, s1
  fcmpe s0, s1
  movi v0.16b, 1
  movi v1.16b, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 1.0004

retire uop (01)cycle (02)schedule 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)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? int retires (ef)
802048003480101101800001008000230032001480103200800102001600161100
802048004180102101800011008000330032000580101200800082001600161100
802048003480101101800001008000130032008380122200800362001600161100
802048003480101101800001008000130032000580101200800082001600161100
802048004180102101800011008000330032000580101200800082001600201100
802048003480101101800001008000130032000580101200800082001600161100
802048003480101101800001008000130032000580101200800082001600161100
802048003480101101800001008000130032000580101200800082001600161100
802048003480101101800001008000130032000580101200800082001600721100
802048003480101101800001008000130032000580101200800082001600161100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 1.0004

retire uop (01)cycle (02)schedule 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)dispatch uop (78)map int uop (7c)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? int retires (ef)
8002480049800212180000208000270320000800202080000201600001110
8002580068800402180019208002570320000800202080000201600001110
8002480034800212180000208000070320000800202080000201600001110
8002480034800212180000208000070320000800202080000201600001110
8002480034800212180000208000070320000800202080000201600001110
8002480034800212180000208000070320000800202080000201600001110
8002480034800212180000208000070320000800202080000201600001110
8002480034800212180000208000070320010800222080008201600001110
8002480034800212180000208000070320000800202080000201600001110
8002480034800212180000208000070320000800202080000201600001110