string: Use builtins for ffs and ffsll

[thirdparty/glibc.git] / string / ffsll.c

diff --git a/string/ffsll.c b/string/ffsll.c
index 7d16250026524a83156eb59ba3503bdb2769ddbd..0ec39a0c5661652ad326e934f4d0d3b20e94ba42 100644 (file)
--- a/string/ffsll.c
+++ b/string/ffsll.c
@@ -18,20 +18,26 @@
 #include <limits.h>
 #define ffsl __something_else
 #include <string.h>
-
 #undef ffsll
+#include <math-use-builtins.h>
+#include <libc-diag.h>
 
 /* Find the first bit set in I.  */
 int
-ffsll (long long int i)
+__ffsll (long long int i)
 {
+#if USE_FFSLL_BUILTIN
+  return __builtin_ffsll (i);
+#else
   unsigned long long int x = i & -i;
 
   if (x <= 0xffffffff)
     return ffs (i);
   else
     return 32 + ffs (i >> 32);
+#endif
 }
+weak_alias (__ffsll, ffsll)
 
 #if ULONG_MAX != UINT_MAX
 #undef ffsl