X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvppinfra%2Fclib.h;h=4629a7defb8e8b7e5af85bb57aefbcd334b4b819;hb=b14c49d2275f6348640572b7b481dad43f3a00d0;hp=9474350c6da198b6c20265958d8483e857ec7507;hpb=dae1c7ed38e9f7a86e66f3674de62778cc981331;p=vpp.git

diff --git a/src/vppinfra/clib.h b/src/vppinfra/clib.h
index 9474350c6da..4629a7defb8 100644
--- a/src/vppinfra/clib.h
+++ b/src/vppinfra/clib.h
@@ -120,6 +120,7 @@
 /* Hints to compiler about hot/cold code. */
 #define PREDICT_FALSE(x) __builtin_expect((x),0)
 #define PREDICT_TRUE(x) __builtin_expect((x),1)
+#define COMPILE_TIME_CONST(x) __builtin_constant_p (x)
 
 /*
  * Compiler barrier
@@ -158,6 +159,16 @@
 #endif
 
 #if defined (count_leading_zeros)
+always_inline uword
+clear_lowest_set_bit (uword x)
+{
+#ifdef __BMI2__
+  return _blsr_u64 (x);
+#else
+  return x ^ (1ULL << count_trailing_zeros (x));
+#endif
+}
+
 always_inline uword
 min_log2 (uword x)
 {
@@ -332,6 +343,14 @@ extract_bits (uword x, int start, int count)
   _x < _y ? _x : _y;				\
 })
 
+#define clib_clamp(x,lo,hi)			\
+({						\
+  __typeof__ (x) _x = (x);			\
+  __typeof__ (lo) _lo = (lo);			\
+  __typeof__ (hi) _hi = (hi);			\
+  _x < _lo ? _lo : (_x > _hi ? _hi : _x);	\
+})
+
 #define clib_abs(x)				\
 ({						\
   __typeof__ (x) _x = (x);			\