diff --git a/src/arith/iter_affine_map.cc b/src/arith/iter_affine_map.cc
index a012b6e80c08..587de531f28f 100644
--- a/src/arith/iter_affine_map.cc
+++ b/src/arith/iter_affine_map.cc
@@ -308,7 +308,7 @@ class IterMapRewriter : public ExprMutator {
     if (expr->IsInstance<IterMapExprNode>()) {
       ErrorLogger(this) << "IterMapExpr or subclasses should only result from calls in "
                         << "IterMapRewriter using DirectMutate.  "
-                        << "Indirect return occurred in " << tvm::PrettyPrint(input_expr);
+                        << "Indirect return occurred in " << input_expr;
     }
     return expr;
   }
@@ -324,8 +324,11 @@ class IterMapRewriter : public ExprMutator {
   PrimExpr VisitExpr_(const FloorModNode* op) final;
 
  private:
-  // Preprocessing common to both FloorDiv and FloorMod
-  IterSumExpr PreprocessDividend(IterMapExpr dividend);
+  /* \brief Preprocessing common to both FloorDiv and FloorMod
+   *
+   * \param dividend The dividend to be manipulated.
+   */
+  IterSumExpr PreprocessDividend(IterMapExpr dividend, PrimExpr original_dividend);
 
   // Create an iterator that represents the expression (split+base), with
   // padding such that the iterator's extents are evenly divisible by
@@ -1238,14 +1241,14 @@ PrimExpr IterMapRewriter::VisitExpr_(const MulNode* op) {
   }
 }
 
-IterSumExpr IterMapRewriter::PreprocessDividend(IterMapExpr dividend) {
+IterSumExpr IterMapRewriter::PreprocessDividend(IterMapExpr dividend, PrimExpr original_dividend) {
   if (dividend->IsInstance<IterSplitExprNode>()) {
     auto split = Downcast<IterSplitExpr>(dividend);
     return IterSumExpr({split}, make_zero(split.dtype()));
   } else if (dividend->IsInstance<IterSumExprNode>()) {
     auto opt_fused = TryFuseIters(Downcast<IterSumExpr>(dividend));
     if (!opt_fused) {
-      ErrorLogger(this) << "Dividend  " << tvm::PrettyPrint(dividend)
+      ErrorLogger(this) << "Dividend  " << tvm::PrettyPrint(original_dividend)
                         << ", can't be written as a single fused IterSum";
       return IterSumExpr();
     }
@@ -1495,7 +1498,7 @@ PrimExpr IterMapRewriter::VisitExpr_(const FloorDivNode* op) {
     return GetRef<PrimExpr>(op);
   }
 
-  IterSumExpr preprocessed = PreprocessDividend(Downcast<IterMapExpr>(a));
+  IterSumExpr preprocessed = PreprocessDividend(Downcast<IterMapExpr>(a), op->a);
   if (!preprocessed.defined()) {
     return GetRef<PrimExpr>(op);
   }
@@ -1580,7 +1583,7 @@ PrimExpr IterMapRewriter::VisitExpr_(const FloorModNode* op) {
     return GetRef<PrimExpr>(op);
   }
 
-  IterSumExpr preprocessed = PreprocessDividend(Downcast<IterMapExpr>(a));
+  IterSumExpr preprocessed = PreprocessDividend(Downcast<IterMapExpr>(a), op->a);
   if (!preprocessed.defined()) {
     return GetRef<PrimExpr>(op);
   }