diff --git a/mlir/include/mlir/Pass/PassRegistry.h b/mlir/include/mlir/Pass/PassRegistry.h
--- a/mlir/include/mlir/Pass/PassRegistry.h
+++ b/mlir/include/mlir/Pass/PassRegistry.h
@@ -197,13 +197,21 @@
   }
 };
 
-/// This function parses the textual representation of a pass pipeline, and adds
-/// the result to 'pm' on success. This function returns failure if the given
-/// pipeline was invalid. 'errorStream' is the output stream used to emit errors
-/// found during parsing.
+/// Parse the textual representation of a pass pipeline, adding the result to
+/// 'pm' on success. Returns failure if the given pipeline was invalid.
+/// 'errorStream' is the output stream used to emit errors found during parsing.
 LogicalResult parsePassPipeline(StringRef pipeline, OpPassManager &pm,
                                 raw_ostream &errorStream = llvm::errs());
 
+/// Parse the given textual representation of a pass pipeline, and return the
+/// parsed pipeline on success. The given pipeline string should be wrapped with
+/// the desired type of operation to root the created operation, i.e.
+/// `builtin.module(cse)` over `cse`. Returns failure if the given pipeline was
+/// invalid. 'errorStream' is the output stream used to emit errors found during
+/// parsing.
+FailureOr<OpPassManager>
+parsePassPipeline(StringRef pipeline, raw_ostream &errorStream = llvm::errs());
+
 //===----------------------------------------------------------------------===//
 // PassPipelineCLParser
 //===----------------------------------------------------------------------===//
diff --git a/mlir/lib/Pass/PassRegistry.cpp b/mlir/lib/Pass/PassRegistry.cpp
--- a/mlir/lib/Pass/PassRegistry.cpp
+++ b/mlir/lib/Pass/PassRegistry.cpp
@@ -482,10 +482,6 @@
   return success();
 }
 
-/// This function parses the textual representation of a pass pipeline, and adds
-/// the result to 'pm' on success. This function returns failure if the given
-/// pipeline was invalid. 'errorStream' is an optional parameter that, if
-/// non-null, will be used to emit errors found during parsing.
 LogicalResult mlir::parsePassPipeline(StringRef pipeline, OpPassManager &pm,
                                       raw_ostream &errorStream) {
   TextualPipeline pipelineParser;
@@ -500,6 +496,24 @@
   return success();
 }
 
+FailureOr<OpPassManager> mlir::parsePassPipeline(StringRef pipeline,
+                                                 raw_ostream &errorStream) {
+  // Pipelines are expected to be of the form `<op-name>(<pipeline>)`.
+  size_t pipelineStart = pipeline.find_first_of('(');
+  if (pipelineStart == 0 || pipelineStart == StringRef::npos ||
+      !pipeline.consume_back(")")) {
+    errorStream << "expected pass pipeline to be wrapped with the anchor "
+                   "operation type, e.g. `builtin.module(...)";
+    return failure();
+  }
+
+  StringRef opName = pipeline.take_front(pipelineStart);
+  OpPassManager pm(opName);
+  if (failed(parsePassPipeline(pipeline.drop_front(1 + pipelineStart), pm)))
+    return failure();
+  return pm;
+}
+
 //===----------------------------------------------------------------------===//
 // PassNameParser
 //===----------------------------------------------------------------------===//
diff --git a/mlir/lib/Transforms/Inliner.cpp b/mlir/lib/Transforms/Inliner.cpp
--- a/mlir/lib/Transforms/Inliner.cpp
+++ b/mlir/lib/Transforms/Inliner.cpp
@@ -754,16 +754,10 @@
     // Skip empty pipelines.
     if (pipeline.empty())
       continue;
-
-    // Pipelines are expected to be of the form `<op-name>(<pipeline>)`.
-    size_t pipelineStart = pipeline.find_first_of('(');
-    if (pipelineStart == StringRef::npos || !pipeline.consume_back(")"))
-      return failure();
-    StringRef opName = pipeline.take_front(pipelineStart);
-    OpPassManager pm(opName);
-    if (failed(parsePassPipeline(pipeline.drop_front(1 + pipelineStart), pm)))
+    FailureOr<OpPassManager> pm = parsePassPipeline(pipeline);
+    if (failed(pm))
       return failure();
-    pipelines.try_emplace(opName, std::move(pm));
+    pipelines.try_emplace(pm->getOpName(), std::move(*pm));
   }
   opPipelines.assign({std::move(pipelines)});
 
diff --git a/mlir/unittests/Pass/CMakeLists.txt b/mlir/unittests/Pass/CMakeLists.txt
--- a/mlir/unittests/Pass/CMakeLists.txt
+++ b/mlir/unittests/Pass/CMakeLists.txt
@@ -1,6 +1,7 @@
 add_mlir_unittest(MLIRPassTests
   AnalysisManagerTest.cpp
   PassManagerTest.cpp
+  PassPipelineParserTest.cpp
 )
 target_link_libraries(MLIRPassTests
   PRIVATE
diff --git a/mlir/unittests/Pass/PassPipelineParserTest.cpp b/mlir/unittests/Pass/PassPipelineParserTest.cpp
new file mode 100644
--- /dev/null
+++ b/mlir/unittests/Pass/PassPipelineParserTest.cpp
@@ -0,0 +1,45 @@
+//===- PassPipelineParserTest.cpp - Pass Parser unit tests ----------------===//
+//
+// 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 "mlir/IR/Builders.h"
+#include "mlir/IR/BuiltinOps.h"
+#include "mlir/Pass/Pass.h"
+#include "mlir/Pass/PassManager.h"
+#include "mlir/Pass/PassRegistry.h"
+#include "llvm/Support/raw_ostream.h"
+#include "gtest/gtest.h"
+
+#include <memory>
+
+using namespace mlir;
+using namespace mlir::detail;
+
+namespace {
+TEST(PassPipelineParserTest, InvalidOpAnchor) {
+  // Helper functor used to parse a pipeline and check that it results in the
+  // provided error message.
+  auto checkParseFailure = [](StringRef pipeline, StringRef expectedErrorMsg) {
+    std::string errorMsg;
+    {
+      llvm::raw_string_ostream os(errorMsg);
+      FailureOr<OpPassManager> result = parsePassPipeline(pipeline, os);
+      EXPECT_TRUE(failed(result));
+    }
+    EXPECT_TRUE(StringRef(errorMsg).contains(expectedErrorMsg));
+  };
+
+  // Handle parse errors when the anchor is incorrectly structured.
+  StringRef anchorErrorMsg =
+      "expected pass pipeline to be wrapped with the anchor operation type";
+  checkParseFailure("module", anchorErrorMsg);
+  checkParseFailure("()", anchorErrorMsg);
+  checkParseFailure("module(", anchorErrorMsg);
+  checkParseFailure("module)", anchorErrorMsg);
+}
+
+} // namespace