Icestorm: LDRH (register, uxtw) measurements

Code:

  ldrh w0, [x6, w7, uxtw]

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	665	1027	1	1026	1000	8238	1000	1000	2000	1	1000
1004	554	1001	1	1000	1000	8292	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:

  ldrh w0, [x6, w7, uxtw]
  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	70153	40108	30107	10001	30130	10003	1859485	693876	40106	30210	10004	60224	20008	30003	10000	30100
40204	70047	40103	30103	10000	30103	10003	1859533	693921	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	1860175	694305	40106	30212	10004	60224	20008	30003	10000	30100
40205	70087	40112	30110	10002	30135	10003	1859608	694073	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): 4.0040

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	70173	40018	30017	10001	30040	10003	1859623	693696	40016	30030	10004	60020	20000	30003	10000	30010
40024	70047	40013	30013	10000	30010	10000	1860786	695176	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60114	20034	30008	10000	30010
40024	70042	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010

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

Chain cycles: 3

Code:

  ldrh w0, [x6, w7, uxtw]
  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): 4.0042

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)
40205	70156	40108	30107	10001	30130	10003	1859539	693896	40106	30210	10004	60220	20008	30003	10000	30100
40204	70042	40102	30102	10000	30103	10003	1859446	694013	40106	30212	10004	60528	20114	30038	10000	30100
40204	70042	40102	30102	10000	30103	10003	1859446	694013	40106	30212	10004	60224	20008	30002	10000	30100
40204	70042	40102	30102	10000	30103	10003	1859446	694013	40106	30212	10004	60224	20008	30002	10000	30100
40204	70047	40102	30102	10000	30103	10055	1865908	697597	40292	30361	10056	60224	20008	30002	10000	30100
40204	70042	40102	30102	10000	30103	10003	1859446	694013	40106	30212	10004	60302	20034	30008	10000	30100
40204	70042	40102	30102	10000	30103	10003	1859446	694013	40106	30212	10004	60224	20008	30002	10000	30100
40204	70046	40102	30102	10000	30103	10003	1859716	694123	40106	30212	10004	60224	20008	30002	10000	30100
40204	70042	40102	30102	10000	30103	10003	1859446	694013	40106	30212	10004	60224	20008	30002	10000	30100
40204	70042	40102	30102	10000	30103	10003	1859446	694013	40106	30212	10004	60224	20008	30002	10000	30100

1000 unrolls and 10 iterations

Result (median cycles for code, minus 3 chain cycles): 4.0040

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	70159	40018	30017	10001	30040	10000	1859415	693584	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10015	1861958	727549	40060	30068	10017	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70051	40012	30012	10000	30010	10000	1859706	694743	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60114	20034	30009	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40024	70040	40012	30012	10000	30010	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010
40025	70070	40020	30018	10002	30045	10000	1859463	694644	40010	30020	10000	60020	20000	30002	10000	30010

Test 4: throughput

Count: 8

Code:

  ldrh w0, [x6, w7, uxtw]
  ldrh w0, [x6, w7, uxtw]
  ldrh w0, [x6, w7, uxtw]
  ldrh w0, [x6, w7, uxtw]
  ldrh w0, [x6, w7, uxtw]
  ldrh w0, [x6, w7, uxtw]
  ldrh w0, [x6, w7, uxtw]
  ldrh w0, [x6, w7, uxtw]

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	40154	80125	101	80024	100	80008	300	256262	80108	200	80012	200	160028	1	80000	100
80204	40063	80105	101	80004	100	80008	300	640268	80108	200	80012	200	160024	1	80000	100
80204	40056	80101	101	80000	100	80008	300	640268	80108	200	80012	200	160024	1	80000	100
80204	40056	80101	101	80000	100	80008	300	640268	80108	200	80012	200	160024	1	80000	100
80204	40056	80101	101	80000	100	80008	300	640268	80108	200	80012	200	160024	1	80000	100
80204	40056	80101	101	80000	100	80008	300	640268	80108	200	80012	200	160024	1	80000	100
80204	40056	80101	101	80000	100	80008	300	640268	80108	200	80012	200	160024	1	80000	100
80204	40056	80101	101	80000	100	80008	300	640268	80108	200	80012	200	160024	1	80000	100
80204	40096	80101	101	80000	100	80010	300	642548	80110	200	80014	200	160024	1	80000	100
80204	40079	80101	101	80000	100	80008	300	328262	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	40292	80045	11	80034	10	80010	30	328522	80020	20	80014	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
80024	40063	80011	11	80000	10	80057	30	556299	80067	20	80069	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

LDRH (register, uxtw)

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