New fix in IsTreeVNInvariant(GenTree* tree)

// Don't allow the hoisting of GT_CLS_VAR an GT_LCL_VAR that were assigned a constant value.

src/jit/optimizer.cpp

@@ -6789,22 +6789,24 @@ void Compiler::optHoistLoopBlocks(unsigned loopNum, ArrayStack<BasicBlock*>* blo
                 return false;
             }
 
-            // Don't hoist constants or nodes that have been assigned a constant value.
-            // Performing such an operation is incorrect as the node being hoisted could be
-            // moved before the assignment that makes it a constant.
-            if (m_compiler->vnStore->IsVNConstant(node->gtVNPair.GetLiberal()))
-            {
-                return false;
-            }
-
             // Tree must be a suitable CSE candidate for us to be able to hoist it.
             return m_compiler->optIsCSEcandidate(node);
         }
 
         bool IsTreeVNInvariant(GenTree* tree)
         {
-            return m_compiler->optVNIsLoopInvariant(tree->gtVNPair.GetLiberal(), m_loopNum,
-                                                    &m_hoistContext->m_curLoopVnInvariantCache);
+            ValueNum vn = tree->gtVNPair.GetLiberal();
+
+            if (m_compiler->vnStore->IsVNConstant(vn))
+            {
+                // Don't allow the hoisting of GT_CLS_VAR an GT_LCL_VAR that were assigned a constant value.
+                // But allow constant GT_ARGPLACE nodes which occur when we have constant args.
+                if (!tree->OperIsConst() && tree->OperGet() != GT_ARGPLACE)
+                {
+                    return false;
+                }
+            }
+            return m_compiler->optVNIsLoopInvariant(vn, m_loopNum, &m_hoistContext->m_curLoopVnInvariantCache);
         }
 
     public: