1 files changed, 14 insertions, 13 deletions
diff --git a/util.c b/util.c
index 73d35f72..1bab7daf 100644
--- a/util.c
+++ b/util.c
@@ -1,4 +1,5 @@
 #include <alloca.h>
+#include <assert.h>
 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -21,23 +22,13 @@
 
 /* Integer stuff: */
 
-u64 rounddown_pow_of_two(u64 n)
-{
-	u64 ret;
-
-	do {
-		ret = n;
-		n &= n - 1;
-	} while (n);
-
-	return ret;
-}
-
 unsigned ilog2(u64 n)
 {
 	unsigned ret = 0;
 
-	while (n) {
+	assert(n > 0);
+
+	while (n > 1) {
 		ret++;
 		n >>= 1;
 	}
@@ -45,6 +36,16 @@ unsigned ilog2(u64 n)
 	return ret;
 }
 
+u64 rounddown_pow_of_two(u64 n)
+{
+	return 1ULL << ilog2(n);
+}
+
+u64 roundup_pow_of_two(u64 n)
+{
+	return 1ULL << (ilog2(n - 1) + 1);
+}
+
 char *skip_spaces(const char *str)
 {
 	while (isspace(*str))