simplify shard option

options.go

@@ -21,32 +21,25 @@ type shardsOption[K comparable, V any] struct {
 	count uint32
 }
 
-func (o *shardsOption[K, V]) ApplyToLRUCache(c *LRUCache[K, V]) {
+func (o *shardsOption[K, V]) getcount(maxcount uint32) uint32 {
 	var shardcount uint32
 	if o.count == 0 {
 		shardcount = nextPowOf2(uint32(runtime.GOMAXPROCS(0) * 16))
 	} else {
 		shardcount = nextPowOf2(o.count)
 	}
-	if maxcount := uint32(len(c.shards)); shardcount > maxcount {
+	if shardcount > maxcount {
 		shardcount = maxcount
 	}
+	return shardcount
+}
 
-	c.mask = uint32(shardcount) - 1
+func (o *shardsOption[K, V]) ApplyToLRUCache(c *LRUCache[K, V]) {
+	c.mask = o.getcount(uint32(len(c.shards))) - 1
 }
 
 func (o *shardsOption[K, V]) ApplyToTTLCache(c *TTLCache[K, V]) {
-	var shardcount uint32
-	if o.count == 0 {
-		shardcount = nextPowOf2(uint32(runtime.GOMAXPROCS(0) * 16))
-	} else {
-		shardcount = nextPowOf2(o.count)
-	}
-	if maxcount := uint32(len(c.shards)); shardcount > maxcount {
-		shardcount = maxcount
-	}
-
-	c.mask = uint32(shardcount) - 1
+	c.mask = o.getcount(uint32(len(c.shards))) - 1
 }
 
 // WithHasher specifies the hasher function of cache.