Extensions
Forms
4 (2 VEX, 2 EVEX)
Data
Intel XED v2026.08.23

Forms

Every encoding of VCOMISS that Intel XED knows, one row per XED instruction form (iform). How to read the notation.
InstructionEncodingRequires
VCOMISS xmm, m32 VCOMISS_XMMd_MEMdVEX.LIG.NP.0F.WIG 2F /rAVX
VCOMISS xmm, xmm VCOMISS_XMMd_XMMdVEX.LIG.NP.0F.WIG 2F /rAVX
VCOMISS xmm, xmm, {sae} VCOMISS_XMMf32_XMMf32_AVX512EVEX.LIG.NP.0F.W0 2F /rAVX10.1 or AVX512F
VCOMISS xmm, m32 VCOMISS_XMMf32_MEMf32_AVX512EVEX.LIG.NP.0F.W0 2F /rAVX10.1 or AVX512F

Intrinsics

The C intrinsics of Clang 23.1.2 that compile to VCOMISS, 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_comieq_ss int _mm_comieq_ss(__m128 __a, __m128 __b)

VCOMISS xmm, xmm VEX.LIG -mavxwith AVX enabled

_mm_comige_ss int _mm_comige_ss(__m128 __a, __m128 __b)

VCOMISS xmm, xmm VEX.LIG -mavxwith AVX enabled

_mm_comigt_ss int _mm_comigt_ss(__m128 __a, __m128 __b)

VCOMISS xmm, xmm VEX.LIG -mavxwith AVX enabled

_mm_comile_ss int _mm_comile_ss(__m128 __a, __m128 __b)

VCOMISS xmm, xmm VEX.LIG -mavxwith AVX enabled

_mm_comilt_ss int _mm_comilt_ss(__m128 __a, __m128 __b)

VCOMISS xmm, xmm VEX.LIG -mavxwith AVX enabled

_mm_comineq_ss int _mm_comineq_ss(__m128 __a, __m128 __b)

VCOMISS xmm, xmm VEX.LIG -mavxwith AVX enabled

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.

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.