From 29dda5066f27d08ee50152689dd339acc6e453a8 Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Sun, 10 Aug 2025 14:40:15 +0300
Subject: [PATCH] Stop doing cpuid repeatedly in runtime

---
 src/util/crc32c.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/util/crc32c.c b/src/util/crc32c.c
index 4afdfd3e..6b658c3b 100644
--- a/src/util/crc32c.c
+++ b/src/util/crc32c.c
@@ -367,9 +367,13 @@ uint32_t crc32c(uint32_t crc, const void *buf, size_t len)
 #ifndef __x86_64__
     return crc32c_sw(crc, buf, len);
 #else
-    int sse42;
-    SSE42(sse42);
-    return sse42 ? crc32c_hw(crc, buf, len) : crc32c_sw(crc, buf, len);
+    static int sse42 = 0;
+    if (!sse42)
+    {
+        SSE42(sse42);
+        sse42 = sse42 ? 2 : 1;
+    }
+    return sse42 == 2 ? crc32c_hw(crc, buf, len) : crc32c_sw(crc, buf, len);
 #endif
 }