diff --git a/mlir/lib/Analysis/DataFlow/ConstantPropagationAnalysis.cpp b/mlir/lib/Analysis/DataFlow/ConstantPropagationAnalysis.cpp
--- a/mlir/lib/Analysis/DataFlow/ConstantPropagationAnalysis.cpp
+++ b/mlir/lib/Analysis/DataFlow/ConstantPropagationAnalysis.cpp
@@ -38,8 +38,10 @@
   // guarantee that folding will be out-of-place. We don't allow in-place
   // folds as the desire here is for simulated execution, and not general
   // folding.
-  if (op->getNumRegions())
+  if (op->getNumRegions()) {
+    markAllPessimisticFixpoint(results);
     return;
+  }
 
   SmallVector<Attribute, 8> constantOperands;
   constantOperands.reserve(op->getNumOperands());
diff --git a/mlir/test/Transforms/sccp.mlir b/mlir/test/Transforms/sccp.mlir
--- a/mlir/test/Transforms/sccp.mlir
+++ b/mlir/test/Transforms/sccp.mlir
@@ -218,7 +218,7 @@
 }
 
 // CHECK-LABEL: inplace_fold
-func.func @inplace_fold(%arg: i1) -> (i32) {
+func.func @inplace_fold() -> (i32) {
   %0 = "test.op_in_place_fold_success"() : () -> i1
   %1 = arith.constant 5 : i32
   cf.cond_br %0, ^a, ^b
@@ -231,3 +231,18 @@
 ^b:
   return %1 : i32
 }
+
+// CHECK-LABEL: op_with_region
+func.func @op_with_region() -> (i32) {
+  %0 = "test.op_with_region"() ({}) : () -> i1
+  %1 = arith.constant 5 : i32
+  cf.cond_br %0, ^a, ^b
+
+^a:
+  // CHECK-NOT: addi
+  %3 = arith.addi %1, %1 : i32
+  return %3 : i32
+
+^b:
+  return %1 : i32
+}