| Opcode*/Instruction | Op/En | 64/32 bit Mode Support | CPUID Feature Flag | Description |
| 0F EF /r1 PXOR mm, mm/m64 | RM | V/V | MMX | Bitwise XOR of mm/m64 and mm. |
| 66 0F EF /r PXOR xmm1, xmm2/m128 | RM | V/V | SSE2 | Bitwise XOR of xmm2/m128 and xmm1. |
| VEX.NDS.128.66.0F.WIG EF /r VPXOR xmm1, xmm2, xmm3/m128 | RVM | V/V | AVX | Bitwise XOR of xmm3/m128 and xmm2. |
| VEX.NDS.256.66.0F.WIG EF /r VPXOR ymm1, ymm2, ymm3/m256 | RVM | V/V | AVX2 | Bitwise XOR of ymm3/m256 and ymm2. |
Notes: 1. See note in Section 2.4, “Instruction Exception Specification” in the Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 2A and Section 22.25.3, “Exception Conditions of Legacy SIMD Instructions Operating on MMX Registers” in the Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 3A.
| Op/En | Operand 1 | Operand 2 | Operand 3 | Operand 4 |
| RM | ModRM:reg (r, w) | ModRM:r/m (r) | NA | NA |
| RVM | ModRM:reg (w) | VEX.vvvv (r) | ModRM:r/m (r) | NA |
Performs a bitwise logical exclusive-OR (XOR) operation on the source operand (second operand) and the destination operand (first operand) and stores the result in the destination operand. Each bit of the result is 1 if the corresponding bits of the two operands are different; each bit is 0 if the corresponding bits of the operands are the same.
In 64-bit mode, using a REX prefix in the form of REX.R permits this instruction to access additional registers (XMM8-XMM15).
Legacy SSE instructions: The source operand can be an MMX technology register or a 64-bit memory location. The destination operand is an MMX technology register. 128-bit Legacy SSE version: The second source operand is an XMM register or a 128-bit memory location. The first source operand and destination operands are XMM registers. Bits (VLMAX-1:128) of the corresponding YMM destination register remain unchanged. VEX.128 encoded version: The second source operand is an XMM register or a 128-bit memory location. The first source operand and destination operands are XMM registers. Bits (VLMAX-1:128) of the destination YMM register are zeroed. VEX.256 encoded version: The second source operand is an YMM register or a 256-bit memory location. The first source operand and destination operands are YMM registers.
Note: VEX.L must be 0, otherwise instructions will #UD.
PXOR (128-bit Legacy SSE version) DEST ← DEST XOR SRC DEST[VLMAX-1:128] (Unmodified) VPXOR (VEX.128 encoded version) DEST ← SRC1 XOR SRC2 DEST[VLMAX-1:128] ← 0 VPXOR (VEX.256 encoded version) DEST ← SRC1 XOR SRC2
| PXOR: | __m64 _mm_xor_si64 (__m64 m1, __m64 m2) |
| (V)PXOR: | __m128i _mm_xor_si128 ( __m128i a, __m128i b) |
| VPXOR: | __m256i _mm256_xor_si256 ( __m256i a, __m256i b) |
None.
None.
See Exceptions Type 4; additionally
| #UD | If VEX.L = 1. |