MOV (M64, R64) - Latency

Experiment 1 (with R8=0)

• Instruction: MOV qword ptr [R14], R8
• Chain instructions: MOV R12, [R14];MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;XOR R14, R12; XOR R14, R12
• Chain latency: ≥6
• Code:

     0:	4d 89 06             	mov    QWORD PTR [r14],r8
     3:	4d 8b 26             	mov    r12,QWORD PTR [r14]
     6:	4d 63 e4             	movsxd r12,r12d
     9:	4d 63 e4             	movsxd r12,r12d
     c:	4d 63 e4             	movsxd r12,r12d
     f:	4d 63 e4             	movsxd r12,r12d
    12:	4d 31 e6             	xor    r14,r12
    15:	4d 31 e6             	xor    r14,r12
  

• Init:

  MOV R8, 0

• Show nanoBench command
• Results:
  • Instructions retired: 8.0
  • Core cycles: 2.33
  • Reference cycles: 1.76
  • UOPS_EXECUTED.THREAD: 9.02

Experiment 2 (with R8=1)

• Instruction: MOV qword ptr [R14], R8
• Chain instructions: MOV R12, [R14];MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;XOR R14, R12; XOR R14, R12
• Chain latency: ≥6
• Code:

     0:	4d 89 06             	mov    QWORD PTR [r14],r8
     3:	4d 8b 26             	mov    r12,QWORD PTR [r14]
     6:	4d 63 e4             	movsxd r12,r12d
     9:	4d 63 e4             	movsxd r12,r12d
     c:	4d 63 e4             	movsxd r12,r12d
     f:	4d 63 e4             	movsxd r12,r12d
    12:	4d 31 e6             	xor    r14,r12
    15:	4d 31 e6             	xor    r14,r12
  

• Init:

  MOV R8, 1

• Show nanoBench command
• Results:
  • Instructions retired: 8.0
  • Core cycles: 2.32
  • Reference cycles: 1.76
  • UOPS_EXECUTED.THREAD: 9.02

Experiment 3 (with R8=2)

• Instruction: MOV qword ptr [R14], R8
• Chain instructions: MOV R12, [R14];MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;XOR R14, R12; XOR R14, R12
• Chain latency: ≥6
• Code:

     0:	4d 89 06             	mov    QWORD PTR [r14],r8
     3:	4d 8b 26             	mov    r12,QWORD PTR [r14]
     6:	4d 63 e4             	movsxd r12,r12d
     9:	4d 63 e4             	movsxd r12,r12d
     c:	4d 63 e4             	movsxd r12,r12d
     f:	4d 63 e4             	movsxd r12,r12d
    12:	4d 31 e6             	xor    r14,r12
    15:	4d 31 e6             	xor    r14,r12
  

• Init:

  MOV R8, 2

• Show nanoBench command
• Results:
  • Instructions retired: 8.0
  • Core cycles: 2.32
  • Reference cycles: 1.6
  • UOPS_EXECUTED.THREAD: 9.02

Experiment 4 (with additional nop, with R8=0)

• Instruction: MOV qword ptr [R14], R8
• Chain instructions: MOV R12, [R14];MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;XOR R14, R12; XOR R14, R12;nop
• Chain latency: ≥6
• Code:

     0:	4d 89 06             	mov    QWORD PTR [r14],r8
     3:	4d 8b 26             	mov    r12,QWORD PTR [r14]
     6:	4d 63 e4             	movsxd r12,r12d
     9:	4d 63 e4             	movsxd r12,r12d
     c:	4d 63 e4             	movsxd r12,r12d
     f:	4d 63 e4             	movsxd r12,r12d
    12:	4d 31 e6             	xor    r14,r12
    15:	4d 31 e6             	xor    r14,r12
    18:	90                   	nop
  

• Init:

  MOV R8, 0

• Show nanoBench command
• Results:
  • Instructions retired: 9.0
  • Core cycles: 2.21
  • Reference cycles: 1.76
  • UOPS_EXECUTED.THREAD: 8.99

Experiment 5 (with additional nop, with R8=1)

• Instruction: MOV qword ptr [R14], R8
• Chain instructions: MOV R12, [R14];MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;XOR R14, R12; XOR R14, R12;nop
• Chain latency: ≥6
• Code:

     0:	4d 89 06             	mov    QWORD PTR [r14],r8
     3:	4d 8b 26             	mov    r12,QWORD PTR [r14]
     6:	4d 63 e4             	movsxd r12,r12d
     9:	4d 63 e4             	movsxd r12,r12d
     c:	4d 63 e4             	movsxd r12,r12d
     f:	4d 63 e4             	movsxd r12,r12d
    12:	4d 31 e6             	xor    r14,r12
    15:	4d 31 e6             	xor    r14,r12
    18:	90                   	nop
  

• Init:

  MOV R8, 1

• Show nanoBench command
• Results:
  • Instructions retired: 9.0
  • Core cycles: 2.22
  • Reference cycles: 1.44
  • UOPS_EXECUTED.THREAD: 9.01

Experiment 6 (with additional nop, with R8=2)

• Instruction: MOV qword ptr [R14], R8
• Chain instructions: MOV R12, [R14];MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;XOR R14, R12; XOR R14, R12;nop
• Chain latency: ≥6
• Code:

     0:	4d 89 06             	mov    QWORD PTR [r14],r8
     3:	4d 8b 26             	mov    r12,QWORD PTR [r14]
     6:	4d 63 e4             	movsxd r12,r12d
     9:	4d 63 e4             	movsxd r12,r12d
     c:	4d 63 e4             	movsxd r12,r12d
     f:	4d 63 e4             	movsxd r12,r12d
    12:	4d 31 e6             	xor    r14,r12
    15:	4d 31 e6             	xor    r14,r12
    18:	90                   	nop
  

• Init:

  MOV R8, 2

• Show nanoBench command
• Results:
  • Instructions retired: 9.0
  • Core cycles: 2.21
  • Reference cycles: 1.6
  • UOPS_EXECUTED.THREAD: 9.01

Experiment 1

• Instruction: MOV qword ptr [R14+R13], R8
• Chain instructions: MOV R12, [R14+R13];MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;XOR R13, R12; XOR R13, R12
• Chain latency: ≥6
• Code:

     0:	4f 89 04 2e          	mov    QWORD PTR [r14+r13*1],r8
     4:	4f 8b 24 2e          	mov    r12,QWORD PTR [r14+r13*1]
     8:	4d 63 e4             	movsxd r12,r12d
     b:	4d 63 e4             	movsxd r12,r12d
     e:	4d 63 e4             	movsxd r12,r12d
    11:	4d 63 e4             	movsxd r12,r12d
    14:	4d 31 e5             	xor    r13,r12
    17:	4d 31 e5             	xor    r13,r12
  

• Init:

  XOR R13, R13

• Show nanoBench command
• Results:
  • Instructions retired: 8.0
  • Core cycles: 18.0
  • Reference cycles: 13.44
  • UOPS_EXECUTED.THREAD: 8.98

Experiment 2 (with additional nop)

• Instruction: MOV qword ptr [R14+R13], R8
• Chain instructions: MOV R12, [R14+R13];MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;MOVSX R12, R12D;XOR R13, R12; XOR R13, R12;nop
• Chain latency: ≥6
• Code:

     0:	4f 89 04 2e          	mov    QWORD PTR [r14+r13*1],r8
     4:	4f 8b 24 2e          	mov    r12,QWORD PTR [r14+r13*1]
     8:	4d 63 e4             	movsxd r12,r12d
     b:	4d 63 e4             	movsxd r12,r12d
     e:	4d 63 e4             	movsxd r12,r12d
    11:	4d 63 e4             	movsxd r12,r12d
    14:	4d 31 e5             	xor    r13,r12
    17:	4d 31 e5             	xor    r13,r12
    1a:	90                   	nop
  

• Init:

  XOR R13, R13

• Show nanoBench command
• Results:
  • Instructions retired: 9.0
  • Core cycles: 18.01
  • Reference cycles: 13.6
  • UOPS_EXECUTED.THREAD: 8.97

Experiment 1

• Instruction: MOV qword ptr [R14], R8
• Chain instructions: MOV R8, [R14];MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D
• Chain latency: ≥4
• Code:

     0:	4d 89 06             	mov    QWORD PTR [r14],r8
     3:	4d 8b 06             	mov    r8,QWORD PTR [r14]
     6:	4d 63 c0             	movsxd r8,r8d
     9:	4d 63 c0             	movsxd r8,r8d
     c:	4d 63 c0             	movsxd r8,r8d
     f:	4d 63 c0             	movsxd r8,r8d
  

• Show nanoBench command
• Results:
  • Instructions retired: 6.0
  • Core cycles: 3.99
  • Reference cycles: 2.72
  • UOPS_EXECUTED.THREAD: 7.0