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

ASR (immediate, 64-bit)

Test 1: uops

Code:

  asr x0, x0, #17

Initialization

  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

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

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)
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000
1005	1060	1015	1015	1040	25603	1000	1000	1000	1001	1000
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000
1004	1030	1001	1001	1000	25603	1000	1000	1000	1001	1000

Test 2: Latency 1->2

Code:

  asr x0, x0, #17

Initialization

  mov x0, 1
  mov x1, 2

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 1.0030

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

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)
10204	10030	10101	10101	10108	259539	10107	10212	10214	10001	10100
10204	10030	10101	10101	10107	259539	10107	10212	10212	10001	10100
10204	10030	10101	10101	10107	259839	10149	10262	10212	10001	10100
10204	10030	10101	10101	10107	259539	10107	10212	10212	10001	10100
10204	10030	10101	10101	10107	259539	10107	10212	10212	10001	10100
10204	10030	10101	10101	10107	259435	10107	10214	10212	10001	10100
10204	10030	10101	10101	10107	259539	10107	10212	10212	10001	10100
10204	10030	10101	10101	10107	259539	10107	10212	10212	10001	10100
10204	10030	10101	10101	10107	259539	10107	10212	10212	10001	10100
10204	10030	10101	10101	10107	259539	10107	10212	10212	10001	10100

1000 unrolls and 10 iterations

Result (median cycles for code): 1.0030

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)	int uops in schedulers (59)	dispatch uop (78)	map int uop (7c)	map int uop inputs (7f)	? int output thing (e9)	? int retires (ef)
10024	10030	10021	10021	0	10030	259474	10020	10020	10020	10011	10010
10024	10030	10021	10021	0	10020	259944	10070	10085	10020	10011	10010
12103	25397	11912	11187	725	11245	259954	10070	10080	10036	10011	10010
10024	10030	10021	10021	0	10020	259591	10020	10020	10020	10011	10010
10024	10030	10021	10021	0	10020	259591	10020	10020	10020	10011	10010
10024	10030	10021	10021	0	10020	259591	10020	10020	10020	10011	10010
10024	10030	10021	10021	0	10020	259591	10020	10020	10020	10011	10010
10024	10030	10021	10021	0	10020	259591	10020	10020	10020	10011	10010
10024	10030	10021	10021	0	10020	259591	10020	10020	10020	10011	10010
10024	10030	10021	10021	0	10020	259591	10020	10020	10020	10011	10010

Test 3: throughput

Count: 8

Code:

  asr x0, x8, #17
  asr x1, x8, #17
  asr x2, x8, #17
  asr x3, x8, #17
  asr x4, x8, #17
  asr x5, x8, #17
  asr x6, x8, #17
  asr x7, x8, #17

Initialization

  mov x8, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

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

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

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)
80204	26890	80115	80115	80120	240360	80120	80224	80222	80015	80100
80204	26749	80115	80115	80120	240360	80120	80224	80224	80015	80100
80204	26737	80115	80115	80120	240360	80120	80224	80224	80015	80100
80204	26737	80115	80115	80120	240360	80120	80224	80224	80015	80100
80204	26737	80115	80115	80120	240360	80120	80224	80220	80014	80100
80205	26880	80158	80158	80172	240360	80120	80224	80224	80015	80100
80204	26737	80115	80115	80120	240360	80120	80224	80224	80015	80100
80204	26737	80115	80115	80120	240360	80120	80224	80224	80015	80100
80204	26737	80115	80115	80120	240360	80120	80224	80276	80059	80100
80204	26737	80115	80115	80120	240360	80120	80224	80224	80015	80100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.3339

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

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)
80024	27944	80038	80038	80043	256143	80042	80046	80020	80011	80010
80024	26784	80021	80021	80020	277404	80020	80020	80020	80011	80010
80024	26713	80021	80021	80020	277404	80020	80020	80020	80011	80010
80024	26713	80021	80021	80020	277404	80020	80020	80020	80011	80010
80024	26713	80021	80021	80020	277404	80020	80020	80020	80011	80010
80024	26713	80021	80021	80020	277404	80020	80020	80020	80011	80010
80024	26713	80021	80021	80020	277404	80020	80020	80020	80011	80010
80024	26713	80021	80021	80020	277404	80020	80020	80020	80011	80010
80024	26742	80021	80021	80020	277404	80020	80020	80020	80011	80010
80024	26714	80021	80021	80020	277404	80020	80020	80020	80011	80010