Mark the other constructor explicit

Author: s-barannikov

llvm/include/llvm/CodeGen/MachineTraceMetrics.h

@@ -162,7 +162,7 @@ class MachineTraceMetrics {
     /// For regunits: Height of the highest user in the trace.
     unsigned Height;
 
-    LiveInReg(VirtRegOrUnit VRegOrUnit, unsigned Height = 0)
+    explicit LiveInReg(VirtRegOrUnit VRegOrUnit, unsigned Height = 0)
         : VRegOrUnit(VRegOrUnit), Height(Height) {}
   };
 

llvm/lib/CodeGen/MachineTraceMetrics.cpp

@@ -1021,7 +1021,7 @@ addLiveIns(const MachineInstr *DefMI, unsigned DefOp,
       return;
     TraceBlockInfo &TBI = BlockInfo[MBB->getNumber()];
     // Just add the register. The height will be updated later.
-    TBI.LiveIns.push_back(VirtRegOrUnit(Reg));
+    TBI.LiveIns.emplace_back(VirtRegOrUnit(Reg));
   }
 }