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

SMAXV (vector, 4S)

Test 1: uops

Code:

  smaxv s0, v0.4s

Initialization

  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: 0.001

Load/store unit issues: 0.000

SIMD/FP unit issues: 1.000

Recorded non-zero counters (first 10 of 64 runs)

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)	? simd retires (ee)
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000
1004	3033	1001	1	1000	1000	75905	1000	1000	2000	1	1000

Test 2: Latency 1->2

Code:

  smaxv s0, v0.4s

Initialization

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

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 3.0033

Recorded non-zero counters (first 10 of 64 runs)

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)
10204	30033	10101	101	10000	100	10000	300	768905	10100	200	10006	200	20084	1	10000	100
10204	30033	10101	101	10000	100	10000	300	768905	10100	200	10004	200	20008	1	10000	100
10204	30033	10101	101	10000	100	10000	300	768905	10100	200	10004	200	20008	1	10000	100
10204	30033	10101	101	10000	100	10000	300	768905	10100	200	10004	200	20008	1	10000	100
10204	30033	10101	101	10000	100	10000	300	768905	10100	200	10004	200	20008	1	10000	100
10204	30033	10101	101	10000	100	10000	300	768905	10100	200	10004	200	20008	1	10000	100
10205	30066	10107	101	10006	100	10031	300	768905	10100	200	10004	200	20008	1	10000	100
10204	30033	10101	101	10000	100	10000	300	768905	10100	200	10004	200	20008	1	10000	100
10205	30066	10107	101	10006	100	10031	300	768905	10100	200	10004	200	20008	1	10000	100
10204	30033	10101	101	10000	100	10000	300	768905	10100	200	10004	200	20008	1	10000	100

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0033

Recorded non-zero counters (first 10 of 64 runs)

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 ldst uop inputs (80)	map simd uop inputs (81)	? int output thing (e9)	? ldst retires (ed)	? simd retires (ee)	? int retires (ef)
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10006	20	0	20000	11	0	10000	10
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10000	20	0	20000	11	0	10000	10
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10000	20	0	20086	11	0	10000	10
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10000	298	197	11458	123	71	5643	190
10024	30133	10037	21	10016	20	10066	70	768905	10020	20	10000	20	0	20000	11	0	10000	10
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10000	20	0	20000	11	0	10000	10
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10000	20	0	20000	11	0	10000	10
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10000	20	0	20000	11	0	10000	10
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10000	20	0	20000	11	0	10000	10
10024	30033	10021	21	10000	20	10000	70	768905	10020	20	10000	20	0	20000	11	0	10000	10

Test 3: throughput

Count: 8

Code:

  smaxv s0, v8.4s
  smaxv s1, v8.4s
  smaxv s2, v8.4s
  smaxv s3, v8.4s
  smaxv s4, v8.4s
  smaxv s5, v8.4s
  smaxv s6, v8.4s
  smaxv s7, v8.4s

Initialization

  movi v8.16b, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.5004

Recorded non-zero counters (first 10 of 64 runs)

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)
80204	40036	80107	101	80006	100	80010	300	320036	80108	200	80012	200	160028	1	80000	100
80204	40045	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160024	1	80000	100
80204	40035	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160024	1	80000	100
80204	40035	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160024	1	80000	100
80204	40035	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160024	1	80000	100
80204	40035	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160024	1	80000	100
80204	40035	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160024	1	80000	100
80204	40035	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160126	1	80000	100
80204	40035	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160024	1	80000	100
80204	40035	80105	101	80004	100	80008	300	320036	80108	200	80012	200	160024	1	80000	100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.5004

Recorded non-zero counters (first 10 of 64 runs)

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 ldst uop inputs (80)	map simd uop inputs (81)	? int output thing (e9)	? ldst retires (ed)	? simd retires (ee)	? int retires (ef)
80024	40108	80029	21	80008	20	80012	70	320044	80030	20	80016	20	0	160000	11	0	80000	10
80024	40035	80021	21	80000	20	80000	70	320000	80020	20	80000	20	0	160000	11	0	80000	10
80024	40035	80021	21	80000	20	80000	70	320216	80076	20	80065	22936	15647	160508	10789	7071	80152	12828
80024	40035	80021	21	80000	20	80000	70	320216	80076	20	80068	20	0	160000	11	0	80000	10
80024	40035	80021	21	80000	20	80000	70	320000	80020	20	80000	20	0	160000	11	0	80000	10
80024	40035	80021	21	80000	20	80000	70	320000	80020	20	80000	20	0	160000	11	0	80000	10
80024	40035	80021	21	80000	20	80000	70	320000	80020	20	80000	20	0	160000	11	0	80000	10
80024	40035	80021	21	80000	20	80000	70	320000	80020	20	80000	20	0	160130	11	0	80000	10
80024	40035	80021	21	80000	20	80000	70	320000	80020	20	80000	20	0	160000	11	0	80000	10
80024	40035	80021	21	80000	20	80000	70	320000	80020	20	80000	20	0	160000	11	0	80000	10