string: fls fixes

- need to check for 0 also for optimized case
- wrong ifdef for flsll
- no need for temp var in inline function

diff --git a/usual/string.h b/usual/string.h
index 72c80d4a68accdd072036d5dcc699351da0e185b..e59964b48eb3d0d8dd97734eb4461cf6e32b4f45 100644 (file)
--- a/usual/string.h
+++ b/usual/string.h
@@ -60,14 +60,13 @@ bool parse_word_list(const char *s, str_cb cb_func, void *cb_arg);
 
 #if defined(__GNUC__) && (__GNUC__ >= 4)
 #define _FLS(sfx, type) \
-       return (8*sizeof(type)) - __builtin_clz ## sfx(x)
+       return (x == 0) ? 0 : ((8*sizeof(type)) - __builtin_clz ## sfx(x))
 #else
 #define _FLS(sfx, type) \
-       unsigned type z = x; \
        unsigned int bit; \
-       if (!z) return 0; \
+       if (x == 0) return 0; \
        /* count from smallest bit, assuming small values */ \
-       for (bit = 1; z > 1; bit++) z >>= 1; \
+       for (bit = 1; x > 1; bit++) x >>= 1; \
        return bit
 #endif
 
@@ -77,8 +76,8 @@ static inline int fls(int x) { _FLS(, int); }
 #ifndef HAVE_FLSL
 static inline int flsl(long x) { _FLS(l, long); }
 #endif
-#ifndef HAVE_FLS
-static inline long long flsll(long long x) { _FLS(ll, long long); }
+#ifndef HAVE_FLSLL
+static inline int flsll(long long x) { _FLS(ll, long long); }
 #endif
 #undef _FLS