Zen4's AVX512 Teardown
Excellent Teardown by "Mysticial" from mersenneforum.org.<p>Cliffnotes:<p>* Zen4 AVX512 is mostly double-pumped: a 256-bit native hardware that processes two halves of the 512-bit register.<p>* No throttling observed<p>* 512-bit shuffle pipeline (!!). A powerful exception to the "double-pumping" found in most other AVX512 instructions.<p>* AMD seemingly handles the AVX512 mask registers better than Intel.<p>* Gather/Scatter slow on AMD's Zen4 implementation.<p>* Intel's 512-bit native load/store unit has clear advantages over AMD's 256-bit load-store unit when reading/writing to L1 cache and beyond.