XCHG (R64, R64)

Experiment 1

Instruction: XCHG R8, R9
Chain instructions: MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D
Chain latency: 9

Code:

   0:	4d 87 c8             	xchg   r8,r9
   3:	4d 63 c0             	movsxd r8,r8d
   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
  12:	4d 63 c0             	movsxd r8,r8d
  15:	4d 63 c0             	movsxd r8,r8d
  18:	4d 63 c0             	movsxd r8,r8d
  1b:	4d 63 c0             	movsxd r8,r8d

Show nanoBench command
Results:
- Instructions retired: 10.0
- Core cycles: 12.0
- Reference cycles: 6.09
- UOPS_RETIRED.ALL: 12.0

Experiment 2

Instruction: XCHG R8, R9

Code:

   0:	4d 87 c8             	xchg   r8,r9

Show nanoBench command
Results:
- Instructions retired: 1.0
- Core cycles: 5.0
- Reference cycles: 2.47
- UOPS_RETIRED.ALL: 3.0

Experiment 3 (with dependency-breaking instructions)

Instruction: XCHG R8, R9
Chain instruction: MOV R9, 0

Code:

   0:	4d 87 c8             	xchg   r8,r9
   3:	49 c7 c1 00 00 00 00 	mov    r9,0x0

Show nanoBench command
Results:
- Instructions retired: 2.0
- Core cycles: 8.0
- Reference cycles: 3.99
- UOPS_RETIRED.ALL: 4.0

Latency operand 1 → 2: 3

Experiment 1

Instruction: XCHG R8, R9
Chain instructions: MOVSX R8, R9D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D
Chain latency: 9

Code:

   0:	4d 87 c8             	xchg   r8,r9
   3:	4d 63 c1             	movsxd r8,r9d
   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
  12:	4d 63 c0             	movsxd r8,r8d
  15:	4d 63 c0             	movsxd r8,r8d
  18:	4d 63 c0             	movsxd r8,r8d
  1b:	4d 63 c0             	movsxd r8,r8d

Show nanoBench command
Results:
- Instructions retired: 10.0
- Core cycles: 12.0
- Reference cycles: 6.02
- UOPS_RETIRED.ALL: 12.0

Latency operand 2 → 1: 3

Experiment 1

Instruction: XCHG R9, R8
Chain instructions: MOVSX R8, R9D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D
Chain latency: 9

Code:

   0:	4d 87 c1             	xchg   r9,r8
   3:	4d 63 c1             	movsxd r8,r9d
   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
  12:	4d 63 c0             	movsxd r8,r8d
  15:	4d 63 c0             	movsxd r8,r8d
  18:	4d 63 c0             	movsxd r8,r8d
  1b:	4d 63 c0             	movsxd r8,r8d

Show nanoBench command
Results:
- Instructions retired: 10.0
- Core cycles: 12.0
- Reference cycles: 6.0
- UOPS_RETIRED.ALL: 12.0

Latency operand 2 → 2: 3

Experiment 1

Instruction: XCHG R9, R8
Chain instructions: MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D;MOVSX R8, R8D
Chain latency: 9

Code:

   0:	4d 87 c1             	xchg   r9,r8
   3:	4d 63 c0             	movsxd r8,r8d
   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
  12:	4d 63 c0             	movsxd r8,r8d
  15:	4d 63 c0             	movsxd r8,r8d
  18:	4d 63 c0             	movsxd r8,r8d
  1b:	4d 63 c0             	movsxd r8,r8d

Show nanoBench command
Results:
- Instructions retired: 10.0
- Core cycles: 12.0
- Reference cycles: 5.92
- UOPS_RETIRED.ALL: 12.0

Experiment 2

Instruction: XCHG R9, R8

Code:

   0:	4d 87 c1             	xchg   r9,r8

Show nanoBench command
Results:
- Instructions retired: 1.0
- Core cycles: 5.0
- Reference cycles: 2.51
- UOPS_RETIRED.ALL: 3.0

Experiment 3 (with dependency-breaking instructions)

Instruction: XCHG R9, R8
Chain instruction: MOV R9, 0

Code:

   0:	4d 87 c1             	xchg   r9,r8
   3:	49 c7 c1 00 00 00 00 	mov    r9,0x0

Show nanoBench command
Results:
- Instructions retired: 2.0
- Core cycles: 8.0
- Reference cycles: 4.01
- UOPS_RETIRED.ALL: 4.0

XCHG (R64, R64) - Latency

Operands

Latency operand 1 → 1: 3

Latency operand 1 → 2: 3

Latency operand 2 → 1: 3

Latency operand 2 → 2: 3

Latency operand 1 → 1: 3

Experiment 1

Experiment 2

Experiment 3 (with dependency-breaking instructions)

Latency operand 1 → 2: 3

Experiment 1

Latency operand 2 → 1: 3

Experiment 1

Latency operand 2 → 2: 3

Experiment 1

Experiment 2

Experiment 3 (with dependency-breaking instructions)