From: Nathan Moinvaziri <nathan@nathanm.com>
Date: Thu, 18 Dec 2025 00:12:30 +0000 (-0800)
Subject: Add comment to adler32_copy_avx512_vnni about lower vector width usage
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a8a12f465758accea6a9dd37d6979c014a42a7c6;p=thirdparty%2Fzlib-ng.git

Add comment to adler32_copy_avx512_vnni about lower vector width usage
---

diff --git a/arch/x86/adler32_avx512_vnni.c b/arch/x86/adler32_avx512_vnni.c
index 68b72ca15..9fbb3bf38 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;