Icestorm: LDRSB (register, 64-bit) measurements

Code:

  ldrsb x0, [x6, x7]

Initialization

  mov x7, #4
  mov x8, 0

(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)	map ldst uop inputs (80)	? int output thing (e9)	? ldst retires (ed)
1005	676	1027	1	1026	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8238	1000	1000	2000	1	1000

Test 2: Latency 1->2 (with chain penalty)

Chain cycles: 3

Code:

  ldrsb x0, [x6, x7]
  eor x8, x8, x0
  eor x8, x8, x0
  add x6, x6, x8

Initialization

  mov x7, #4
  mov x8, 0

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code, minus 3 chain cycles): 4.0047

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)	? int retires (ef)
40205	70149	40108	30107	10001	30130	10003	1859539	693896	40106	30210	10004	60224	20008	30003	10000	30100
40204	70049	40103	30103	10000	30103	10003	1859635	694083	40106	30212	10004	60224	20008	30003	10000	30100
40204	70049	40103	30103	10000	30103	10003	1859689	694105	40106	30212	10004	60224	20008	30003	10000	30100
40204	70049	40103	30103	10000	30103	10003	1859635	694083	40106	30212	10004	60224	20008	30003	10000	30100
40204	70049	40103	30103	10000	30103	10003	1859635	694083	40106	30212	10004	60224	20008	30003	10000	30100
40204	70049	40103	30103	10000	30103	10003	1859635	694083	40106	30212	10004	60224	20008	30003	10000	30100
40205	70079	40111	30109	10002	30135	10003	1859635	694083	40106	30212	10004	60224	20008	30003	10000	30100
40204	70049	40103	30103	10000	30103	10003	1859635	694083	40106	30212	10004	60224	20008	30003	10000	30100
40204	70049	40103	30103	10000	30103	10003	1859635	694083	40106	30212	10004	60224	20008	30003	10000	30100
40204	70049	40103	30103	10000	30103	10003	1859635	694083	40106	30212	10004	60224	20008	30003	10000	30100

1000 unrolls and 10 iterations

Result (median cycles for code, minus 3 chain cycles): 4.0047

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)	? int retires (ef)
40025	70166	40018	30017	10001	30040	10000	1859760	694754	40010	30020	10000	60020	20000	30003	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859706	694734	40010	30020	10000	60020	20000	30003	10000	30010
40024	70108	40013	30013	10000	30010	10015	1860853	695194	40060	30071	10017	60020	20000	30002	10000	30010
40024	70049	40013	30013	10000	30010	10000	1859841	694789	40010	30020	10000	60020	20000	30003	10000	30010
40024	70049	40013	30013	10000	30010	10000	1859706	694734	40010	30020	10000	60020	20000	30003	10000	30010
40024	70049	40013	30013	10000	30010	10000	1859706	694734	40010	30020	10000	60020	20000	30003	10000	30010
40024	70049	40013	30013	10000	30010	10000	1859706	694734	40010	30020	10000	60020	20000	30003	10000	30010
40024	70049	40013	30013	10000	30010	10000	1859706	694734	40010	30020	10000	60020	20000	30003	10000	30010
40024	70049	40013	30013	10000	30010	10000	1859706	694734	40010	30020	10000	60020	20000	30003	10000	30010
40024	70049	40013	30013	10000	30010	10000	1859706	694734	40010	30020	10000	60020	20000	30003	10000	30010

Test 3: Latency 1->3 (with chain penalty)

Chain cycles: 3

Code:

  ldrsb x0, [x6, x7]
  eor x8, x8, x0
  eor x8, x8, x0
  add x7, x7, x8

Initialization

  mov x7, #4
  mov x8, 0

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code, minus 3 chain cycles): 4.0049

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)	? int retires (ef)
40205	70147	40108	30107	10001	30130	10003	1859485	693876	40106	30210	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100
40205	70077	40111	30109	10002	30135	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859581	694063	40106	30212	10004	60224	20008	30003	10000	30100

1000 unrolls and 10 iterations

Result (median cycles for code, minus 3 chain cycles): 4.0042

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)	? int retires (ef)
40025	70153	40018	30017	10001	30040	10000	1859517	694664	40010	30020	10000	60020	20000	30003	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859517	694664	40010	30020	10000	60020	20000	30002	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859517	694664	40010	30020	10000	60020	20000	30002	10000	30010
40024	70105	40012	30012	10000	30010	10000	1859841	694796	40010	30020	10000	60020	20000	30002	10000	30010
40024	70047	40012	30012	10000	30010	10000	1859517	694664	40010	30020	10000	60020	20000	30002	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859517	694664	40010	30020	10000	60020	20000	30002	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859517	694664	40010	30020	10000	60020	20000	30002	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859517	694664	40010	30020	10000	60020	20000	30002	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859517	694664	40010	30020	10000	60020	20000	30002	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859517	694664	40010	30020	10000	60020	20000	30002	10000	30010

Test 4: throughput

Count: 8

Code:

  ldrsb x0, [x6, x7]
  ldrsb x0, [x6, x7]
  ldrsb x0, [x6, x7]
  ldrsb x0, [x6, x7]
  ldrsb x0, [x6, x7]
  ldrsb x0, [x6, x7]
  ldrsb x0, [x6, x7]
  ldrsb x0, [x6, x7]

Initialization

  mov x7, 8

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.5007

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)	? int retires (ef)
80205	40176	80135	101	80034	100	80008	300	248190	80108	200	80012	200	160024	1	80000	100
80204	40063	80101	101	80000	100	80008	300	640430	80108	200	80012	200	160024	1	80000	100
80204	40052	80101	101	80000	100	80008	300	640196	80108	200	80012	200	160024	1	80000	100
80204	40052	80101	101	80000	100	80008	300	640196	80108	200	80012	200	160024	1	80000	100
80204	40052	80101	101	80000	100	80008	300	640196	80108	200	80012	200	160024	1	80000	100
80204	40052	80101	101	80000	100	80008	300	640196	80108	200	80012	200	160024	1	80000	100
80204	40052	80101	101	80000	100	80059	300	329359	80159	200	80072	200	160024	1	80000	100
80204	40052	80101	101	80000	100	80010	300	640208	80110	200	80014	200	160024	1	80000	100
80204	40052	80101	101	80000	100	80008	300	640196	80108	200	80012	200	160024	1	80000	100
80204	40052	80101	101	80000	100	80008	300	640196	80108	200	80012	200	160024	1	80000	100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.5007

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)	? int retires (ef)
80025	40219	80045	11	80034	10	80008	30	400262	80018	20	80012	20	160000	1	80000	10
80024	40054	80011	11	80000	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10
80024	40054	80011	11	80000	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10
80024	40054	80011	11	80000	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10
80025	40110	80048	11	80037	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10
80024	40054	80011	11	80000	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10
80024	40054	80011	11	80000	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10
80024	40054	80011	11	80000	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10
80024	40054	80011	11	80000	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10
80024	40054	80011	11	80000	10	80000	30	640238	80010	20	80000	20	160000	1	80000	10

LDRSB (register, 64-bit)

Test 1: uops

1000 unrolls and 1 iteration

Test 2: Latency 1->2 (with chain penalty)

100 unrolls and 100 iterations

1000 unrolls and 10 iterations

Test 3: Latency 1->3 (with chain penalty)

100 unrolls and 100 iterations

1000 unrolls and 10 iterations

Test 4: throughput

100 unrolls and 100 iterations

1000 unrolls and 10 iterations