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

SQSHRN (8H)

Test 1: uops

Code:

  sqshrn v0.8b, v0.8h, #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)
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000
1004303310011100010007590510001000100011000

Test 2: Latency 1->2

Code:

  sqshrn v0.8b, v0.8h, #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)
1020430033101011011000010010000300768905101002001000620010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100
1020430033101011011000010010000300768905101002001000420010004110000100

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)
10024300331002121100002010000707689051002020100062010000111000010
10024300331002121100002010000707689051002020100002010000111000010
10024300331002121100002010000707689051002020100002010000111000010
10024300331002121100002010000707689051002020100002010000111000010
10024300331002121100002010000707689051002020100002010000111000010
10024300331002121100002010000707689051002020100002010000111000010
10024300331002121100002010000707689051002020100002010000111000010
10024300331002121100002010000707689051002020100002010000111000010
10024300331002121100002010000707689051002020100002010000111000010
10024300331002121100002010000707689051002020100002010000111000010

Test 3: throughput

Count: 8

Code:

  sqshrn v0.8b, v8.8h, #3
  sqshrn v1.8b, v8.8h, #3
  sqshrn v2.8b, v8.8h, #3
  sqshrn v3.8b, v8.8h, #3
  sqshrn v4.8b, v8.8h, #3
  sqshrn v5.8b, v8.8h, #3
  sqshrn v6.8b, v8.8h, #3
  sqshrn v7.8b, v8.8h, #3
  movi v8.16b, 9

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 0.5004

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)
8020440077801051018000410080008300320036801082008001220080014180000100
8020440045801051018000410080008300320036801082008001220080012180000100
8020440035801051018000410080008300320036801082008001220080012180000100
8020440035801051018000410080008300320036801082008001220080012180000100
8020440035801051018000410080008300320036801082008001220080012180000100
8020440035801051018000410080008300320036801082008001220080012180000100
8020440035801051018000410080008300320036801082008001220080012180000100
8020440035801051018000410080008300320036801082008001220080012180000100
8020440035801051018000410080008300320036801082008001220080012180000100
8020440035801051018000410080008300320036801082008001220080012180000100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 0.5161

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)ldst uops in schedulers (5b)dispatch uop (78)map int uop (7c)map ldst uop (7d)map simd uop (7e)map int uop inputs (7f)map simd uop inputs (81)? int output thing (e9)? simd retires (ee)? int retires (ef)
800244012580027218000602080010070032004480030200800162080000118000010
800244003580021218000002080000070032000080020200800002080000118000010
800244003580021218000002080000070032000080020200800002080000118000010
800244003580021218000002080000070032000080020200800002080000118000010
800244003580021218000002080000070032000080020200800002080000118000010
800244003580021218000002080000070032000080020200800002080000118000010
800244003580021218000002080000070032000080020200800002080000118000010
800244003580021218000002080000070032000080020200800002080000118000010
800244141880917218089602080900075032455681161220811392080840118000010
826414815783735178681023926165381039069032358080917200809072080791118000010