Remove reversal of loop processing order

src/coreclr/jit/gentree.cpp

@@ -4520,7 +4520,7 @@ unsigned Compiler::gtSetEvalOrder(GenTree* tree)
                     // We generate `xorp* tgtReg, tgtReg` which is 3-5 bytes
                     // but which can be elided by the instruction decoder.
 
-                    costEx = 1;
+                    costEx = 1; //2;
                     costSz = 2;
                 }
                 else

src/coreclr/jit/optimizer.cpp

@@ -6287,18 +6287,9 @@ void Compiler::optHoistLoopNest(unsigned lnum, LoopHoistContext* hoistCtxt)
         BitVecTraits m_visitedTraits(fgBBNumMax * 2, this);
         BitVec       m_visited(BitVecOps::MakeEmpty(&m_visitedTraits));
 
-        // Since loops in optLoopTable are arranged in reverse execution order, arrange
-        // them back in execution order before processing.
-        ArrayStack<unsigned> childLoops(getAllocatorLoopHoist());
         for (unsigned child = optLoopTable[lnum].lpChild; child != BasicBlock::NOT_IN_LOOP;
              child          = optLoopTable[child].lpSibling)
         {
-            childLoops.Push(child);
-        }
-
-        while (!childLoops.Empty())
-        {
-            unsigned child = childLoops.Pop();
             optHoistLoopNest(child, hoistCtxt);
 
             if (optLoopTable[child].lpFlags & LPFLG_HAS_PREHEAD)