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

DSB (NSH)

Test 1: uops

Code:

  dsb nsh

(no loop instructions)

1000 unrolls and 1 iteration

Retires: 1.000

Issues: 1.000

Integer unit issues: 0.001

Load/store unit issues: 1.000

SIMD/FP unit issues: 0.000

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

retire uop (01)	cycle (02)	schedule uop (52)	schedule int uop (53)	schedule ldst uop (55)	dispatch ldst uop (58)	simd uops in schedulers (5a)	dispatch uop (78)	map ldst uop (7d)	? int output thing (e9)	? ldst retires (ed)
1004	16033	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16033	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16028	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16028	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16028	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16028	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16028	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16028	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16028	1001	1	1000	1000	4000	1000	1000	1	1000
1004	16028	1001	1	1000	1000	4000	1000	1000	1	1000

Test 2: throughput

Code:

  dsb nsh

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 16.0028

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)	schedule ldst uop (55)	dispatch int uop (56)	dispatch simd uop (57)	dispatch ldst uop (58)	int uops in schedulers (59)	simd uops in schedulers (5a)	dispatch uop (78)	map int uop (7c)	map ldst uop (7d)	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)
10204	160033	10105	101	0	10004	100	0	10006	300	40024	10106	200	10006	200	0	0	1	10000	0	100
10204	160033	10105	101	0	10004	100	0	10004	300	40016	10104	200	10004	200	0	0	1	9999	0	100
10204	160028	10105	101	0	10004	100	0	10004	300	40016	10104	200	10004	200	0	0	1	10000	0	100
10204	160028	10105	101	0	10004	100	0	10004	300	40016	10104	200	10004	200	0	0	1	10000	0	100
10204	160028	10105	101	0	10004	100	0	10004	300	40016	10104	200	10004	200	0	0	1	10000	0	100
10204	160053	10116	101	0	10015	100	0	10004	300	40016	10104	200	10004	200	0	0	1	10000	0	100
10204	160028	10105	101	0	10004	100	0	10016	300	40058	10116	200	10016	200	0	0	1	10000	0	100
10204	160051	10113	101	0	10012	100	0	10006	300	40024	10106	200	10006	200	0	0	1	9999	0	100
10204	160045	10113	101	0	10012	100	0	10004	300	40016	10104	200	10004	200	0	0	1	10000	0	100
10204	160028	10105	101	0	10004	100	0	10004	300	40016	10104	200	10004	200	0	0	1	10000	0	100

1000 unrolls and 10 iterations

Result (median cycles for code): 16.0028

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

retire uop (01)	cycle (02)	schedule uop (52)	schedule int uop (53)	schedule ldst uop (55)	dispatch int uop (56)	dispatch ldst uop (58)	int uops in schedulers (59)	simd uops in schedulers (5a)	dispatch uop (78)	map int uop (7c)	map ldst uop (7d)	map int uop inputs (7f)	map ldst uop inputs (80)	? int output thing (e9)	? ldst retires (ed)	? simd retires (ee)	? int retires (ef)
10024	160060	10023	11	10012	10	10004	30	40016	10014	20	10004	20	0	1	10000	0	10
10024	160033	10011	11	10000	10	10000	30	40000	10010	20	10000	20	0	1	10000	0	10
10024	160028	10011	11	10000	10	10000	30	40000	10010	20	10000	20	0	1	10000	0	10
10024	160046	10023	11	10012	10	10000	30	40000	10010	20	10000	20	0	1	10000	0	10
10024	160028	10011	11	10000	10	10012	30	40048	10022	20	10012	20	0	1	10000	0	10
10024	160028	10011	11	10000	10	10000	30	40000	10010	20	10000	20	0	1	10000	0	10
10024	160028	10011	11	10000	10	10000	30	40000	10010	20	10000	20	0	1	9999	0	10
10024	160028	10011	11	10000	10	10000	30	40000	10010	20	10000	20	0	1	10000	0	10
10024	160028	10011	11	10000	10	10000	30	40000	10010	20	10000	20	0	1	10000	0	10
10024	160028	10011	11	10000	10	10000	30	40000	10010	20	10000	20	0	1	10000	0	10