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

LD1 (multiple, 4 regs, 4H)

Test 1: uops

Code:

  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop ; nop
  mov x0, 1
  mov x1, 2
  mov x8, 0

(no loop instructions)

1000 unrolls and 1 iteration

Retires (minus 60 nops): 4.000

Issues: 4.000

Integer unit issues: 0.001

Load/store unit issues: 4.000

SIMD/FP unit issues: 0.000

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)
640052988140091400840001200040004000400014000
640042949940011400040001200040004000400014000
640042949940011400040001200040004000400014000
640042949540011400040001204740004000400014000
640042949640011400040001200040004000400014000
640042950040011400040001200040004000400014000
640042949840011400040001200040004000400014000
640042949540011400040001200040004000400014000
640042962140011400040001200040004000400014000
640042994240011400040001200240004000400014000

Test 2: throughput

Count: 8

Code:

  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  ld1 { v0.4h, v1.4h, v2.4h, v3.4h }, [x6]
  mov x7, x6
  mov x8, x6
  mov x9, x6
  mov x10, x6
  mov x11, x6
  mov x12, x6
  mov x13, x6

(fused SUBS/B.cc loop)

100 unrolls and 100 iterations

Result (median cycles for code divided by count): 2.0007

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)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 ldst uop inputs (80)? int output thing (e9)? ldst retires (ed)? int retires (ef)
320205160172320137101320036100320010300992194032011020032001602003200161320000100
3202041600573201011013200001003200103002560260032011020032001602003200161320000100
3202041600483201011013200001003200103002560040032011020032001602003200161320000100
3202041600483201011013200001003200103002560040032011020032001602003200161320000100
3202051601013201371013200361003200103002560296032011020032001602003200161320000100
3202041600483201011013200001003200103002560040032011020032001602003200161320000100
3202041600483201011013200001003200103002560040032011020032001602003200161320000100
3202041600483201011013200001003200103002560040032011020032001602003200721320000100
3202041600573201011013200001003200103002560346032011020032001602003200161320000100
3202051601063201371013200361003200103002560040032011020032001602003200161320000100

1000 unrolls and 10 iterations

Result (median cycles for code divided by count): 2.0006

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)
32002616025232007311320062103200103025604223200202032001620320000132000010
32002416005432001111320000103200003025666623200102032000020320000132000010
32002416004532001111320000103200003025599983200102032000020320000132000010
32002416004532001111320000103200003025599983200102032000020320072132000010
32002416004532001111320000103200003025599983200102032000020320000132000010
32002416004532001111320000103200003025599983200102032000020320000132000010
32002416004532001111320000103200003025599983200102032000020320000132000010
32002416004532001111320000103200003025599983200102032000020320072132000010
32002416004832001111320000103200003025599983200102032000020320000132000010
32002416004532001111320000103200003025599983200102032000020320072132000010