cts: enable half-NDR for clock nets by default. Fix clock tree level list check.

Signed-off-by: Jonas Gava <[email protected]>

Author: jfgava

src/cts/src/CtsOptions.h

@@ -350,7 +350,7 @@ class CtsOptions : public odb::dbBlockCallBackObj
   std::string dummyload_prefix_ = "clkload";
   MasterCount dummy_count_;
   bool repairClockNets_ = false;
-  NdrStrategy ndrStrategy_ = NdrStrategy::NONE;
+  NdrStrategy ndrStrategy_ = NdrStrategy::HALF;
 };
 
 }  // namespace cts

src/cts/src/TritonCTS.cpp

@@ -1582,7 +1582,7 @@ std::vector<int> TritonCTS::getAllClockTreeLevels(Clock& clockNet)
   std::set<int> uniqueLevels;
 
   clockNet.forEachSubNet([&](ClockSubNet& subNet) {
-    if (!subNet.isLeafLevel()) {
+    if (!subNet.isLeafLevel() && subNet.getTreeLevel() != -1) {
       uniqueLevels.insert(subNet.getTreeLevel());
     }
   });