core: Get doublings in trickle-timer the elegant way

src/core/model/trickle-timer.cc

@@ -21,6 +21,7 @@
 
 #include "log.h"
 
+#include <bit>
 #include <limits>
 
 namespace ns3
@@ -116,20 +117,7 @@ TrickleTimer::GetDoublings() const
         return 0;
     }
 
-    // Here we assume that m_ticks is a power of 2.
-    // This could have been way more elegant by using
-    // std::countl_zero() defined in the <bit> header
-    // which is c++20 - so not yet widely available.
-
-    uint64_t ticks = m_ticks;
-    uint8_t doublings = 0;
-    while (ticks != 1)
-    {
-        ticks >>= 1;
-        doublings++;
-    }
-
-    return doublings;
+    return std::countr_zero(m_ticks);
 }
 
 uint16_t

utils/codespell-ignored-lines

@@ -85,6 +85,9 @@ Network Animator nam.  It is not possible to run a simulation
 ./src/core/examples/hash-example.cc
 6ed21de2  brand-newness       peripherial
 
+./src/core/model/trickle-timer.cc:120
+    return std::countr_zero(m_ticks);
+
 ./src/dsr/model/dsr-routing.cc:243, 246, 3360, 3363
             .AddAttribute("GratReplyHoldoff",
                           MakeTimeAccessor(&DsrRouting::m_gratReplyHoldoff),