Add fls() for non-constant values.

src/core/bitops.c

+#include <strings.h>
+
+int __flsl ( long x ) {
+	int r = 0;
+
+	for ( r = 0 ; x ; r++ ) {
+		x >>= 1;
+	}
+	return r;
+}

src/include/strings.h

 	return r;
 }
 
-#define __constant_fls(x) __constant_flsl(x)
-
 /* We don't actually have these functions yet */
-extern int __fls ( int x );
 extern int __flsl ( long x );
 
 #define flsl( x ) \
 	( __builtin_constant_p ( x ) ? __constant_flsl ( x ) : __flsl ( x ) )
 
-#define fls( x ) \
-	( __builtin_constant_p ( x ) ? __constant_fls ( x ) : __fls ( x ) )
+#define fls( x ) flsl ( x )
 
 extern int strcasecmp ( const char *s1, const char *s2 );