diff --git a/mlir/include/mlir/Transforms/VerifyFullyConverted.h b/mlir/include/mlir/Transforms/VerifyFullyConverted.h
new file mode 100644
--- /dev/null
+++ b/mlir/include/mlir/Transforms/VerifyFullyConverted.h
@@ -0,0 +1,67 @@
+//===- VerifyFullyConverted.h - Conversion verification pass ----*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This header file defines a base class for a generic pass that verifies all
+// operations conform to the specification of a ConversionTarget.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_TRANSFORMS_VERIFY_FULLY_CONVERTED_H
+#define MLIR_TRANSFORMS_VERIFY_FULLY_CONVERTED_H
+
+#include "mlir/Pass/Pass.h"
+#include "mlir/Support/LLVM.h"
+#include "mlir/Transforms/DialectConversion.h"
+#include "mlir/Transforms/Passes.h"
+#include "llvm/Support/FormatVariadic.h"
+
+using namespace mlir;
+
+template <typename ConcretePass>
+class VerifyFullyConvertedPass
+    : public PassWrapper<ConcretePass, OperationPass<>> {
+public:
+  void runOnOperation() override {
+    DenseSet<Operation *> illegalOps;
+    this->getOperation()->walk([&](Operation *op) {
+      if (!this->getConversionTarget().isLegal(op)) {
+        illegalOps.insert(op);
+      }
+    });
+    if (!illegalOps.empty()) {
+      emitLegalizationErrors(illegalOps);
+      return this->signalPassFailure();
+    }
+  }
+
+protected:
+  virtual ConversionTarget getConversionTarget() = 0;
+
+private:
+  void emitLegalizationErrors(const DenseSet<Operation *> &illegalOps) {
+    // Print op errors for each of the illegal ops that still remain.
+    llvm::MapVector<StringRef, int> opNameCounts;
+    for (Operation *illegalOp : illegalOps) {
+      StringRef opName = illegalOp->getName().getStringRef();
+      opNameCounts[opName]++;
+      illegalOp->emitOpError() << ": illegal op still exists";
+    }
+
+    std::vector<std::string> errorMessages;
+    errorMessages.reserve(opNameCounts.size());
+    for (const auto &opInfo : opNameCounts) {
+      errorMessages.push_back(
+          llvm::formatv("\t{0} (count: {1})", opInfo.first, opInfo.second));
+    }
+    emitError(this->getOperation()->getLoc())
+        << "The following illegal operations still remain: \n"
+        << llvm::join(errorMessages, "\n") << "\n";
+  }
+};
+
+#endif // MLIR_TRANSFORMS_VERIFY_FULLY_CONVERTED_H
diff --git a/mlir/test/Transforms/test-verify-fully-converted.mlir b/mlir/test/Transforms/test-verify-fully-converted.mlir
new file mode 100644
--- /dev/null
+++ b/mlir/test/Transforms/test-verify-fully-converted.mlir
@@ -0,0 +1,16 @@
+// RUN: mlir-opt %s -split-input-file -test-verify-fully-converted -verify-diagnostics -allow-unregistered-dialect
+
+// -----
+
+// expected-error@+1 {{The following illegal operations still remain}}
+module {
+  func @f() -> () {
+    // expected-error@+1 {{'test.some_op' op : illegal op still exists}}
+    %0 = "test.some_op"() : () -> tensor<i32>
+    // expected-error@+1 {{'test.other_op' op : illegal op still exists}}
+    %1 = "test.other_op"() : () -> tensor<i32>
+    return
+  }
+}
+
+
diff --git a/mlir/test/lib/Transforms/CMakeLists.txt b/mlir/test/lib/Transforms/CMakeLists.txt
--- a/mlir/test/lib/Transforms/CMakeLists.txt
+++ b/mlir/test/lib/Transforms/CMakeLists.txt
@@ -32,6 +32,7 @@
   TestSCFUtils.cpp
   TestSparsification.cpp
   TestVectorTransforms.cpp
+  TestVerifyFullyConverted.cpp
 
   EXCLUDE_FROM_LIBMLIR
 
diff --git a/mlir/test/lib/Transforms/TestVerifyFullyConverted.cpp b/mlir/test/lib/Transforms/TestVerifyFullyConverted.cpp
new file mode 100644
--- /dev/null
+++ b/mlir/test/lib/Transforms/TestVerifyFullyConverted.cpp
@@ -0,0 +1,29 @@
+#include "TestDialect.h"
+#include "mlir/Pass/Pass.h"
+#include "mlir/Transforms/DialectConversion.h"
+#include "mlir/Transforms/VerifyFullyConverted.h"
+
+using namespace mlir;
+
+namespace {
+class TestVerifyFullyConvertedPass
+    : public VerifyFullyConvertedPass<TestVerifyFullyConvertedPass> {
+protected:
+  ConversionTarget getConversionTarget() override {
+    ConversionTarget target(getContext());
+    target.markUnknownOpDynamicallyLegal([](Operation *) { return true; });
+    target.addIllegalDialect<test::TestDialect>();
+    return target;
+  }
+};
+} // namespace
+
+namespace mlir {
+namespace test {
+void registerVerifyFullyConverted() {
+  PassRegistration<TestVerifyFullyConvertedPass>(
+      "test-verify-fully-converted",
+      "Test verification that no illegal ops remain");
+}
+} // namespace test
+} // namespace mlir
diff --git a/mlir/tools/mlir-opt/mlir-opt.cpp b/mlir/tools/mlir-opt/mlir-opt.cpp
--- a/mlir/tools/mlir-opt/mlir-opt.cpp
+++ b/mlir/tools/mlir-opt/mlir-opt.cpp
@@ -56,6 +56,7 @@
 namespace test {
 void registerConvertCallOpPass();
 void registerInliner();
+void registerVerifyFullyConverted();
 void registerMemRefBoundCheck();
 void registerPatternsTestPass();
 void registerSimpleParametricTilingPass();
@@ -125,6 +126,7 @@
 
   test::registerConvertCallOpPass();
   test::registerInliner();
+  test::registerVerifyFullyConverted();
   test::registerMemRefBoundCheck();
   test::registerPatternsTestPass();
   test::registerSimpleParametricTilingPass();