From a8a12f465758accea6a9dd37d6979c014a42a7c6 Mon Sep 17 00:00:00 2001
From: Nathan Moinvaziri <nathan@nathanm.com>
Date: Wed, 17 Dec 2025 16:12:30 -0800
Subject: Add comment to adler32_copy_avx512_vnni about lower vector width
 usage

---
 arch/x86/adler32_avx512_vnni.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/adler32_avx512_vnni.c b/arch/x86/adler32_avx512_vnni.c
index 68b72ca15c..9fbb3bf381 100644
--- a/arch/x86/adler32_avx512_vnni.c
+++ b/arch/x86/adler32_avx512_vnni.c
@@ -109,6 +109,7 @@ rem_peel:
     return adler;
 }
 
+/* Use 256-bit vectors when copying because 512-bit variant is slower. */
 Z_INTERNAL uint32_t adler32_copy_avx512_vnni(uint32_t adler, uint8_t *dst, const uint8_t *src, size_t len) {
     if (UNLIKELY(src == NULL)) return 1L;
     if (UNLIKELY(len == 0)) return adler;
-- 
cgit 0.0.5-2-1-g0f52