AVX512DQ

AVX512DQ, short for Advanced Vector Extensions 512 Doubleword and Quadword, is an extension of Intel’s AVX‑512 instruction set architecture. It was introduced as part of the Xeon Scalable "Broadwell‑EP" processors and later integrated into subsequent Intel server and workstation microarchitectures such as Skylake‑Server, Cascade Lake, and Rocket Lake. The extension adds new instructions that permit 512‑bit operations on double‑precision floating‑point (64‑bit) and integer (32‑bit) data types, as well as support for quadword integer accumulation.

The core contribution of AVX512DQ is the expansion of arithmetic and logical operations that can be performed on 64‑bit and 32‑bit operands within a single instruction. This includes double‑precision vector multiplication and addition that operate on multiple elements simultaneously, enhancing performance for scientific computing, machine learning, and data‑intensive workloads. Furthermore, AVX512DQ introduces new support for the AVX512VBMI instructions to improve inner‑loop execution latency, especially in cryptographic and compression tasks.

Hardware support for AVX512DQ is limited to Intel’s high‑end Xeon and some Core models, while AMD’s Zen microarchitecture does not implement the AVX512DQ set. Software that relies on AVX512DQ must enable appropriate compiler flags such as -mavx512dq for GCC and Clang, or /arch:AVX512DQ for MSVC. When executing non‑supported instructions, a fatal exception is thrown in the operating system, which typically results in an illegal instruction crash unless the code is designed to detect and fallback to lower‑level instruction sets.

The introduction of AVX512DQ has driven optimizations in many numerical libraries, including Intel MKL, OpenBLAS, and others, by allowing these libraries to generate vector‑intensive kernels that reduce instruction count and improve throughput on compatible CPUs.