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

SHRN2 (2D)

Test 1: uops

Code:

  shrn2 v0.4s, v1.2d, #3
  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

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)
1004303310011100010007590510001000200011000
1004303310011100010007590510001000200011000
1004303310011100010007590510001000200011000
1004303310011100010007590510001000200011000
1004303310011100010007590510001000200011000
1004303310011100010007590510001000200011000
1004303310011100010007488510001000200011000
1004303310011100010007590510001000200011000
1004303310011100010007590510001000200011000
1004303310011100010007590510001000200011000

Test 2: Latency 1->1

Code:

  shrn2 v0.4s, v1.2d, #3
  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

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)
1020430033101011011000010010000300768905101002001000620020008110000100
1020430033101011011000010010000300768905101002001000420020012110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0033

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)
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000687692471005120100442020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10025300661002721100062010031707689051002020100002020000111000010

Test 3: Latency 1->2

Code:

  shrn2 v0.4s, v0.2d, #3
  movi v0.16b, 1

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code): 3.0033

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)
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100
1020430033101011011000010010000300768905101002001000420020008110000100

1000 unrolls and 10 iterations

Result (median cycles for code): 3.0033

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)
10024300331002121100002010000707689051002020100042020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010
10024300331002121100002010000707689051002020100002020000111000010

Test 4: throughput

Count: 8

Code:

  movi v0.16b, 0
  shrn2 v0.4s, v8.2d, #3
  movi v1.16b, 0
  shrn2 v1.4s, v8.2d, #3
  movi v2.16b, 0
  shrn2 v2.4s, v8.2d, #3
  movi v3.16b, 0
  shrn2 v3.4s, v8.2d, #3
  movi v4.16b, 0
  shrn2 v4.4s, v8.2d, #3
  movi v5.16b, 0
  shrn2 v5.4s, v8.2d, #3
  movi v6.16b, 0
  shrn2 v6.4s, v8.2d, #3
  movi v7.16b, 0
  shrn2 v7.4s, v8.2d, #3
  movi v8.16b, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.5011

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)
1602044044980109101800081008001230032005280112200800122001600981160000100
1602044010580110101800091008001330032005280112200800122001600961160000100
1602054012180145101800441008004830032005680113200800132001600241160000100
1602054012180145101800441008004830032005280112200800122001600241160000100
1602044008680109101800081008001230032005280112200800122001600241160000100
1602044008680109101800081008001230032020080149200800492001600241160000100
1602044008680109101800081008001230032019680148200800482001600241160000100
1602044008680109101800081008001230032005280112200800122001600241160000100
1602044008680109101800081008001230032005280112200800122001600241160000100
1602044008680109101800081008001230032005280112200800122001600241160000100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.5053

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)
1600244380080019118000810800123032005280022208001220160000116000010
1600244131280011118000010800003032019280057208004720160000116000010
1600244042480011118000010800003032019280057208004720160000116000010
1600244051780011118000010800003032000080010208000020160000116000010
1600244048580011118000010800003032000080010208000020160000116000010
1600244046380011118000010800003032000080010208000020160000116000010
1600244039880011118000010800003032000080010208000020160000116000010
1600244039880011118000010800003032000080010208000020160000116000010
1600244038780011118000010800003032000080010208000020160000116000010
1600244040580011118000010800003032000080010208000020160000116000010

Test 5: throughput

Count: 16

Code:

  shrn2 v0.4s, v16.2d, #3
  shrn2 v1.4s, v16.2d, #3
  shrn2 v2.4s, v16.2d, #3
  shrn2 v3.4s, v16.2d, #3
  shrn2 v4.4s, v16.2d, #3
  shrn2 v5.4s, v16.2d, #3
  shrn2 v6.4s, v16.2d, #3
  shrn2 v7.4s, v16.2d, #3
  shrn2 v8.4s, v16.2d, #3
  shrn2 v9.4s, v16.2d, #3
  shrn2 v10.4s, v16.2d, #3
  shrn2 v11.4s, v16.2d, #3
  shrn2 v12.4s, v16.2d, #3
  shrn2 v13.4s, v16.2d, #3
  shrn2 v14.4s, v16.2d, #3
  shrn2 v15.4s, v16.2d, #3
  movi v16.16b, 17

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.5002

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)
160204800521601071011600061001600103006400361601082001600122003200281160000100
160205800701601411011600401001600523006400361601082001600122003200241160000100
160204800351601051011600041001600083006400441601102001600142003200241160000100
160204800351601051011600041001600083006400361601082001600122003200241160000100
160204800351601051011600041001600083006400361601082001600122003200241160000100
160204800351601051011600041001600083006400361601082001600122003200241160000100
160204800351601051011600041001600083006400361601082001600122003200241160000100
160204800351601051011600041001600083006400361601082001600122003200241160000100
160205800711601451011600441001600563006400361601082001600122003200241160000100
160204800351601051011600041001600083006400361601082001600122003200241160000100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.5002

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)
160024801191600151116000410160008306400361600182016001220320000116000010
160024800471600111116000010160000306400001600102016000020320000116000010
160024800351600111116000010160000306400001600102016000020320000116000010
160024800351600111116000010160000306400001600102016000020320000116000010
160024800351600111116000010160000306400001600102016000020320000116000010
160024800351600111116000010160000306400001600102016000020320000116000010
160024800351600111116000010160000306402081600642016006120320000116000010
160024800351600111116000010160000306400001600102016000020320000116000010
160024800351600111116000010160000306400001600102016000020320000116000010
160024800351600111116000010160000306400001600102016000020320000116000010