| Opcode | Instruction | Op/En | 64-Bit Mode | Compat/Leg Mode | Description |
|---|---|---|---|---|---|
| 34 ib | XOR AL, imm8 | I | Valid | Valid | AL XOR imm8. |
| 35 iw | XOR AX, imm16 | I | Valid | Valid | AX XOR imm16. |
| 35 id | XOR EAX, imm32 | I | Valid | Valid | EAX XOR imm32. |
| REX.W + 35 id | XOR RAX, imm32 | I | Valid | N.E. | RAX XOR imm32 (sign-extended). |
| 80 /6 ib | XOR r/m8, imm8 | MI | Valid | Valid | r/m8 XOR imm8. |
| REX + 80 /6 ib | XOR r/m8*, imm8 | MI | Valid | N.E. | r/m8 XOR imm8. |
| 81 /6 iw | XOR r/m16, imm16 | MI | Valid | Valid | r/m16 XOR imm16. |
| 81 /6 id | XOR r/m32, imm32 | MI | Valid | Valid | r/m32 XOR imm32. |
| REX.W + 81 /6 id | XOR r/m64, imm32 | MI | Valid | N.E. | r/m64 XOR imm32 (sign-extended). |
| 83 /6 ib | XOR r/m16, imm8 | MI | Valid | Valid | r/m16 XOR imm8 (sign-extended). |
| 83 /6 ib | XOR r/m32, imm8 | MI | Valid | Valid | r/m32 XOR imm8 (sign-extended). |
| REX.W + 83 /6 ib | XOR r/m64, imm8 | MI | Valid | N.E. | r/m64 XOR imm8 (sign-extended). |
| 30 /r | XOR r/m8, r8 | MR | Valid | Valid | r/m8 XOR r8. |
| REX + 30 /r | XOR r/m8*, r8* | MR | Valid | N.E. | r/m8 XOR r8. |
| 31 /r | XOR r/m16, r16 | MR | Valid | Valid | r/m16 XOR r16. |
| 31 /r | XOR r/m32, r32 | MR | Valid | Valid | r/m32 XOR r32. |
| REX.W + 31 /r | XOR r/m64, r64 | MR | Valid | N.E. | r/m64 XOR r64. |
| 32 /r | XOR r8, r/m8 | RM | Valid | Valid | r8 XOR r/m8. |
| REX + 32 /r | XOR r8*, r/m8* | RM | Valid | N.E. | r8 XOR r/m8. |
| 33 /r | XOR r16, r/m16 | RM | Valid | Valid | r16 XOR r/m16. |
| 33 /r | XOR r32, r/m32 | RM | Valid | Valid | r32 XOR r/m32. |
| REX.W + 33 /r | XOR r64, r/m64 | RM | Valid | N.E. | r64 XOR r/m64. |
NOTES:
*
In 64-bit mode, r/m8 can not be encoded to access the following byte registers if a REX prefix is used: AH, BH, CH, DH.
| Op/En | Operand 1 | Operand 2 | Operand 3 | Operand 4 |
| I | AL/AX/EAX/RAX | imm8/16/32 | NA | NA |
| MI | ModRM:r/m (r, w) | imm8/16/32 | NA | NA |
| MR | ModRM:r/m (r, w) | ModRM:reg (r) | NA | NA |
| RM | ModRM:reg (r, w) | ModRM:r/m (r) | NA | NA |
Performs a bitwise exclusive OR (XOR) operation on the destination (first) and source (second) operands and stores the result in the destination operand location. The source operand can be an immediate, a register, or a memory location; the destination operand can be a register or a memory location. (However, two memory oper-ands cannot be used in one instruction.) Each bit of the result is 1 if the corresponding bits of the operands are different; each bit is 0 if the corresponding bits are the same.
This instruction can be used with a LOCK prefix to allow the instruction to be executed atomically.
In 64-bit mode, using a REX prefix in the form of REX.R permits access to additional registers (R8-R15). Using a REX prefix in the form of REX.W promotes operation to 64 bits. See the summary chart at the beginning of this section for encoding data and limits.
DEST ← DEST XOR SRC;
The OF and CF flags are cleared; the SF, ZF, and PF flags are set according to the result. The state of the AF flag is undefined.
| #GP(0) |
If the destination operand points to a non-writable segment. If a memory operand effective address is outside the CS, DS, ES, FS, or GS segment limit. If the DS, ES, FS, or GS register contains a NULL segment selector. |
| #SS(0) | If a memory operand effective address is outside the SS segment limit. |
| #PF(fault-code) | If a page fault occurs. |
| #AC(0) | If alignment checking is enabled and an unaligned memory reference is made while the current privilege level is 3. |
| #UD | If the LOCK prefix is used but the destination is not a memory operand. |
| #GP | If a memory operand effective address is outside the CS, DS, ES, FS, or GS segment limit. |
| #SS | If a memory operand effective address is outside the SS segment limit. |
| #UD | If the LOCK prefix is used but the destination is not a memory operand. |
| #GP(0) | If a memory operand effective address is outside the CS, DS, ES, FS, or GS segment limit. |
| #SS(0) | If a memory operand effective address is outside the SS segment limit. |
| #PF(fault-code) | If a page fault occurs. |
| #AC(0) | If alignment checking is enabled and an unaligned memory reference is made. |
| #UD | If the LOCK prefix is used but the destination is not a memory operand. |
Same exceptions as in protected mode.
| #SS(0) | If a memory address referencing the SS segment is in a non-canonical form. |
| #GP(0) | If the memory address is in a non-canonical form. |
| #PF(fault-code) | If a page fault occurs. |
| #AC(0) | If alignment checking is enabled and an unaligned memory reference is made while the current privilege level is 3. |
| #UD | If the LOCK prefix is used but the destination is not a memory operand. |