x86-64.net

Instruction

VPCMPEQQ

Compares packed quadwords for equality; the VEX form writes all-ones or zero elements, the EVEX form a mask register.

Extensions
Forms
10 (4 VEX, 6 EVEX)
Data
Intel XED v2026.08.23

Forms

Every encoding of VPCMPEQQ that Intel XED knows, one row per XED instruction form (iform). How to read the notation.
InstructionEncodingRequires
VPCMPEQQ xmm, xmm, m128 VPCMPEQQ_XMMdq_XMMdq_MEMdqVEX.128.66.0F38.WIG 29 /rAVX
VPCMPEQQ xmm, xmm, xmm VPCMPEQQ_XMMdq_XMMdq_XMMdqVEX.128.66.0F38.WIG 29 /rAVX
VPCMPEQQ ymm, ymm, m256 VPCMPEQQ_YMMqq_YMMqq_MEMqqVEX.256.66.0F38.WIG 29 /rAVX2
VPCMPEQQ ymm, ymm, ymm VPCMPEQQ_YMMqq_YMMqq_YMMqqVEX.256.66.0F38.WIG 29 /rAVX2
VPCMPEQQ k {k}, zmm, zmm VPCMPEQQ_MASKmskw_MASKmskw_ZMMu64_ZMMu64_AVX512EVEX.512.66.0F38.W1 29 /rAVX10.1 or AVX512F
VPCMPEQQ k {k}, zmm, m512/m64bcst VPCMPEQQ_MASKmskw_MASKmskw_ZMMu64_MEMu64_AVX512EVEX.512.66.0F38.W1 29 /rAVX10.1 or AVX512F
VPCMPEQQ k {k}, xmm, xmm VPCMPEQQ_MASKmskw_MASKmskw_XMMu64_XMMu64_AVX512EVEX.128.66.0F38.W1 29 /rAVX10.1 or AVX512F + AVX512VL
VPCMPEQQ k {k}, xmm, m128/m64bcst VPCMPEQQ_MASKmskw_MASKmskw_XMMu64_MEMu64_AVX512EVEX.128.66.0F38.W1 29 /rAVX10.1 or AVX512F + AVX512VL
VPCMPEQQ k {k}, ymm, ymm VPCMPEQQ_MASKmskw_MASKmskw_YMMu64_YMMu64_AVX512EVEX.256.66.0F38.W1 29 /rAVX10.1 or AVX512F + AVX512VL
VPCMPEQQ k {k}, ymm, m256/m64bcst VPCMPEQQ_MASKmskw_MASKmskw_YMMu64_MEMu64_AVX512EVEX.256.66.0F38.W1 29 /rAVX10.1 or AVX512F + AVX512VL

Intrinsics

The C intrinsics of Clang 23.1.2 that compile to VPCMPEQQ, each with the form it compiles to and the Clang options it needs. The forms come from compiling every intrinsic and decoding the result with Intel XED; all intrinsics A–Z explains the method.

IntrinsicCompiles to
_mm_cmpeq_epi64 __m128i _mm_cmpeq_epi64(__m128i __V1, __m128i __V2)

VPCMPEQQ xmm, xmm, xmm VEX.128 -mavxwith AVX enabled

_mm_cmpeq_epi64_mask __mmask8 _mm_cmpeq_epi64_mask(__m128i A, __m128i B)

VPCMPEQQ k, xmm, xmm EVEX.128 -mavx512vl

_mm_cmpeq_epu64_mask __mmask8 _mm_cmpeq_epu64_mask(__m128i A, __m128i B)

VPCMPEQQ k, xmm, xmm EVEX.128 -mavx512vl

_mm_mask_cmpeq_epi64_mask __mmask8 _mm_mask_cmpeq_epi64_mask(__mmask8 k, __m128i A, __m128i B)

VPCMPEQQ k {k}, xmm, xmm EVEX.128 -mavx512vl

_mm_mask_cmpeq_epu64_mask __mmask8 _mm_mask_cmpeq_epu64_mask(__mmask8 k, __m128i A, __m128i B)

VPCMPEQQ k {k}, xmm, xmm EVEX.128 -mavx512vl

_mm256_cmpeq_epi64 __m256i _mm256_cmpeq_epi64(__m256i __a, __m256i __b)

VPCMPEQQ ymm, ymm, ymm VEX.256 -mavx2

_mm256_cmpeq_epi64_mask __mmask8 _mm256_cmpeq_epi64_mask(__m256i A, __m256i B)

VPCMPEQQ k, ymm, ymm EVEX.256 -mavx512vl

_mm256_cmpeq_epu64_mask __mmask8 _mm256_cmpeq_epu64_mask(__m256i A, __m256i B)

VPCMPEQQ k, ymm, ymm EVEX.256 -mavx512vl

_mm256_mask_cmpeq_epi64_mask __mmask8 _mm256_mask_cmpeq_epi64_mask(__mmask8 k, __m256i A, __m256i B)

VPCMPEQQ k {k}, ymm, ymm EVEX.256 -mavx512vl

_mm256_mask_cmpeq_epu64_mask __mmask8 _mm256_mask_cmpeq_epu64_mask(__mmask8 k, __m256i A, __m256i B)

VPCMPEQQ k {k}, ymm, ymm EVEX.256 -mavx512vl

_mm512_cmpeq_epi64_mask __mmask8 _mm512_cmpeq_epi64_mask(__m512i A, __m512i B)

VPCMPEQQ k, zmm, zmm EVEX.512 -mavx512f

_mm512_mask_cmpeq_epi64_mask __mmask8 _mm512_mask_cmpeq_epi64_mask(__mmask8 k, __m512i A, __m512i B)

VPCMPEQQ k, zmm, zmm EVEX.512 -mavx512f

_mm512_cmpeq_epu64_mask __mmask8 _mm512_cmpeq_epu64_mask(__m512i A, __m512i B)

VPCMPEQQ k, zmm, zmm EVEX.512 -mavx512f

_mm512_mask_cmpeq_epu64_mask __mmask8 _mm512_mask_cmpeq_epu64_mask(__mmask8 k, __m512i A, __m512i B)

VPCMPEQQ k, zmm, zmm EVEX.512 -mavx512f

CPUID and processors

Each form belongs to an XED ISA set. A form can be used when the processor reports every CPUID bit of one of its ISA set's alternatives.

CPUID requirements and processors of the XED ISA sets above. Alternatives are separated by “or”; processors follow XED’s chip model, which covers AMD processors up to Zen 2.
ISA setCPUIDProcessors in XED
AVX

AVX
CPUID.01H:ECX[28] AVX

Sandy Bridge, Ivy Bridge, Haswell, Broadwell, Skylake, Comet Lake, Cannon Lake, Ice Lake (client), Tiger Lake, Alder Lake, Arrow Lake, Panther Lake, Nova Lake, Skylake-SP, Cascade Lake, Cooper Lake, Ice Lake (server), Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids, Sierra Forest, Clearwater Forest, Knights Landing, Knights Mill, Bulldozer, Piledriver, Zen, Zen+, Zen 2
AVX2

AVX2
CPUID.(EAX=07H,ECX=0):EBX[5] AVX2

Haswell, Broadwell, Skylake, Comet Lake, Cannon Lake, Ice Lake (client), Tiger Lake, Alder Lake, Arrow Lake, Panther Lake, Nova Lake, Skylake-SP, Cascade Lake, Cooper Lake, Ice Lake (server), Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids, Sierra Forest, Clearwater Forest, Knights Landing, Knights Mill, Zen, Zen+, Zen 2
AVX512F_512

AVX10.1
CPUID.(EAX=07H,ECX=1):EDX[19] AVX10
CPUID.(EAX=24H,ECX=0):EBX[7:0] ≥ 1 AVX10 version

or

AVX512F
CPUID.(EAX=07H,ECX=0):EBX[16] AVX512F

Cannon Lake, Ice Lake (client), Tiger Lake, Nova Lake, Skylake-SP, Cascade Lake, Cooper Lake, Ice Lake (server), Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids, Knights Landing, Knights Mill
AVX512F_128

AVX10.1
CPUID.(EAX=07H,ECX=1):EDX[19] AVX10
CPUID.(EAX=24H,ECX=0):EBX[7:0] ≥ 1 AVX10 version

or

AVX512F + AVX512VL
CPUID.(EAX=07H,ECX=0):EBX[16] AVX512F
CPUID.(EAX=07H,ECX=0):EBX[31] AVX512VL

Cannon Lake, Ice Lake (client), Tiger Lake, Nova Lake, Skylake-SP, Cascade Lake, Cooper Lake, Ice Lake (server), Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids
AVX512F_256

AVX10.1
CPUID.(EAX=07H,ECX=1):EDX[19] AVX10
CPUID.(EAX=24H,ECX=0):EBX[7:0] ≥ 1 AVX10 version

or

AVX512F + AVX512VL
CPUID.(EAX=07H,ECX=0):EBX[16] AVX512F
CPUID.(EAX=07H,ECX=0):EBX[31] AVX512VL

Cannon Lake, Ice Lake (client), Tiger Lake, Nova Lake, Skylake-SP, Cascade Lake, Cooper Lake, Ice Lake (server), Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids

More AVX10.1 instructions

All 686 AVX10.1 instructions

Sources

  1. Intel XED v2026.08.23 (commit 0bcb6237345c): forms, encodings, ISA sets, CPUID bits and chip model.
  2. Clang's x86 intrinsic headers, LLVM 23.1.2 (commit 85ac56026243): the intrinsics, their signatures and doc comments, and the Clang of that release, which compiled each of them.
  3. Intel Advanced Vector Extensions 10.2 Architecture Specification, revision 6.0 (361050-006, January 2026)

The tables are derived from Intel XED, Copyright Intel Corporation, licensed under the Apache License 2.0; x86-64.net converted and reformatted them. The intrinsics and their signatures come from Clang, part of the LLVM Project, licensed under the Apache License 2.0 with LLVM Exceptions. The text is our own.