diff --git a/headers/private/kernel/util/BitUtils.h b/headers/private/kernel/util/BitUtils.h
index e4169dffe8..ed092caab7 100644
--- a/headers/private/kernel/util/BitUtils.h
+++ b/headers/private/kernel/util/BitUtils.h
@@ -40,6 +40,31 @@ count_set_bits(uint32 v)
 }
 
 
+static inline uint32
+fls(uint32 value)
+{
+	if (value == 0)
+		return 0;
+
+#if __has_builtin(__builtin_clz)
+	return ((sizeof(value) * 8) - __builtin_clz(value));
+#else
+	// https://graphics.stanford.edu/~seander/bithacks.html#IntegerLog
+	static const uint32 masks[] = {
+		0xaaaaaaaa,
+		0xcccccccc,
+		0xf0f0f0f0,
+		0xff00ff00,
+		0xffff0000
+	};
+	uint32 result = (value & masks[0]) != 0;
+	for (int i = 4; i > 0; i--)
+		result |= ((value & masks[i]) != 0) << i;
+	return result + 1;
+#endif
+}
+
+
 static inline uint32
 log2(uint32 v)
 {
diff --git a/src/add-ons/kernel/file_systems/ramfs/Misc.h b/src/add-ons/kernel/file_systems/ramfs/Misc.h
index d869777e7f..e609287bf7 100644
--- a/src/add-ons/kernel/file_systems/ramfs/Misc.h
+++ b/src/add-ons/kernel/file_systems/ramfs/Misc.h
@@ -17,62 +17,6 @@ static inline C min(const C &a, const C &b) { return (a < b ? a : b); }
 template<typename C>
 static inline C max(const C &a, const C &b) { return (a > b ? a : b); }
 
-// find last (most significant) set bit
-static inline
-int
-fls(uint32 value)
-{
-	if (!value)
-		return -1;
-	int index = 0;
-#define HAND_OPTIMIZED_FLS	1
-#if !HAND_OPTIMIZED_FLS
-// This is the algorithm in its pure form.
-	const uint32 masks[] = {
-		0xffff0000,
-		0xff00ff00,
-		0xf0f0f0f0,
-		0xcccccccc,
-		0xaaaaaaaa,
-	};
-	int range = 16;
-	for (int i = 0; i < 5; i++) {
-		if (value & masks[i]) {
-			index += range;
-			value &= masks[i];
-		}
-		range /= 2;
-	}
-#else	// HAND_OPTIMIZED_FLS
-// This is how the compiler should optimize it for us: Unroll the loop and
-// inline the masks.
-	// 0: 0xffff0000
-	if (value & 0xffff0000) {
-		index += 16;
-		value &= 0xffff0000;
-	}
-	// 1: 0xff00ff00
-	if (value & 0xff00ff00) {
-		index += 8;
-		value &= 0xff00ff00;
-	}
-	// 2: 0xf0f0f0f0
-	if (value & 0xf0f0f0f0) {
-		index += 4;
-		value &= 0xf0f0f0f0;
-	}
-	// 3: 0xcccccccc
-	if (value & 0xcccccccc) {
-		index += 2;
-		value &= 0xcccccccc;
-	}
-	// 4: 0xaaaaaaaa
-	if (value & 0xaaaaaaaa)
-		index++;
-#endif	// HAND_OPTIMIZED_FLS
-	return index;
-}
-
 // node_child_hash
 static inline
 uint32