diff --git a/flang/lib/Lower/CMakeLists.txt b/flang/lib/Lower/CMakeLists.txt
--- a/flang/lib/Lower/CMakeLists.txt
+++ b/flang/lib/Lower/CMakeLists.txt
@@ -7,6 +7,7 @@
   Coarray.cpp
   ComplexExpr.cpp
   ConvertType.cpp
+  ConvertExpr.cpp
   DoLoopHelper.cpp
   FIRBuilder.cpp
   IntrinsicCall.cpp
diff --git a/flang/lib/Lower/ConvertExpr.cpp b/flang/lib/Lower/ConvertExpr.cpp
new file mode 100644
--- /dev/null
+++ b/flang/lib/Lower/ConvertExpr.cpp
@@ -0,0 +1,95 @@
+//===-- ConvertExpr.cpp ---------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "flang/Common/idioms.h"
+#include "flang/Lower/IntrinsicCall.h"
+#include "flang/Lower/Support/BoxValue.h"
+
+mlir::Value fir::getBase(const fir::ExtendedValue &ex) {
+  return std::visit(Fortran::common::visitors{
+                        [](const fir::UnboxedValue &x) { return x; },
+                        [](const auto &x) { return x.getAddr(); },
+                    },
+                    ex.box);
+}
+
+llvm::raw_ostream &fir::operator<<(llvm::raw_ostream &os,
+                                   const fir::CharBoxValue &box) {
+  os << "boxchar { addr: " << box.getAddr() << ", len: " << box.getLen()
+     << " }";
+  return os;
+}
+
+llvm::raw_ostream &fir::operator<<(llvm::raw_ostream &os,
+                                   const fir::ArrayBoxValue &box) {
+  os << "boxarray { addr: " << box.getAddr();
+  if (box.getLBounds().size()) {
+    os << ", lbounds: [";
+    llvm::interleaveComma(box.getLBounds(), os);
+    os << "]";
+  } else {
+    os << ", lbounds: all-ones";
+  }
+  os << ", shape: [";
+  llvm::interleaveComma(box.getExtents(), os);
+  os << "]}";
+  return os;
+}
+
+llvm::raw_ostream &fir::operator<<(llvm::raw_ostream &os,
+                                   const fir::CharArrayBoxValue &box) {
+  os << "boxchararray { addr: " << box.getAddr() << ", len : " << box.getLen();
+  if (box.getLBounds().size()) {
+    os << ", lbounds: [";
+    llvm::interleaveComma(box.getLBounds(), os);
+    os << "]";
+  } else {
+    os << " lbounds: all-ones";
+  }
+  os << ", shape: [";
+  llvm::interleaveComma(box.getExtents(), os);
+  os << "]}";
+  return os;
+}
+
+llvm::raw_ostream &fir::operator<<(llvm::raw_ostream &os,
+                                   const fir::BoxValue &box) {
+  os << "box { addr: " << box.getAddr();
+  if (box.getLen())
+    os << ", size: " << box.getLen();
+  if (box.params.size()) {
+    os << ", type params: [";
+    llvm::interleaveComma(box.params, os);
+    os << "]";
+  }
+  if (box.getLBounds().size()) {
+    os << ", lbounds: [";
+    llvm::interleaveComma(box.getLBounds(), os);
+    os << "]";
+  }
+  if (box.getExtents().size()) {
+    os << ", shape: [";
+    llvm::interleaveComma(box.getExtents(), os);
+    os << "]";
+  }
+  os << "}";
+  return os;
+}
+
+llvm::raw_ostream &fir::operator<<(llvm::raw_ostream &os,
+                                   const fir::ProcBoxValue &box) {
+  os << "boxproc: { addr: " << box.getAddr() << ", context: " << box.hostContext
+     << "}";
+  return os;
+}
+
+llvm::raw_ostream &fir::operator<<(llvm::raw_ostream &os,
+                                   const fir::ExtendedValue &ex) {
+  std::visit([&](const auto &value) { os << value; }, ex.box);
+  return os;
+}
diff --git a/flang/lib/Optimizer/Dialect/FIROps.cpp b/flang/lib/Optimizer/Dialect/FIROps.cpp
--- a/flang/lib/Optimizer/Dialect/FIROps.cpp
+++ b/flang/lib/Optimizer/Dialect/FIROps.cpp
@@ -1395,15 +1395,28 @@
 //===----------------------------------------------------------------------===//
 // WhereOp
 //===----------------------------------------------------------------------===//
-
 void fir::WhereOp::build(mlir::OpBuilder &builder, OperationState &result,
                          mlir::Value cond, bool withElseRegion) {
+  build(builder, result, llvm::None, cond, withElseRegion);
+}
+
+void fir::WhereOp::build(mlir::OpBuilder &builder, OperationState &result,
+                         mlir::TypeRange resultTypes, mlir::Value cond,
+                         bool withElseRegion) {
   result.addOperands(cond);
+  result.addTypes(resultTypes);
+
   mlir::Region *thenRegion = result.addRegion();
+  thenRegion->push_back(new mlir::Block());
+  if (resultTypes.empty())
+    WhereOp::ensureTerminator(*thenRegion, builder, result.location);
+
   mlir::Region *elseRegion = result.addRegion();
-  WhereOp::ensureTerminator(*thenRegion, builder, result.location);
-  if (withElseRegion)
-    WhereOp::ensureTerminator(*elseRegion, builder, result.location);
+  if (withElseRegion) {
+    elseRegion->push_back(new mlir::Block());
+    if (resultTypes.empty())
+      WhereOp::ensureTerminator(*elseRegion, builder, result.location);
+  }
 }
 
 static mlir::ParseResult parseWhereOp(OpAsmParser &parser,