[mlir][Python] Context managers for Context, InsertionPoint, Location.

[stellaraccident]

Summary

• Finishes support for Context, InsertionPoint and Location to be carried by the thread using context managers.
• Introduces type casters and utilities so that DefaultPyMlirContext and DefaultPyLocation in method signatures does the right thing (allows explicit or gets from the thread context).
• Extend the rules for the thread context stack to handle nesting, appropriately inheriting and clearing depending on whether the context is the same.
• Refactors all method signatures to follow the new convention on trailing parameters for defaulting parameters (loc, ip, context). When the objects are carried in the thread context, this allows most explicit uses of these values to be elided.
• Removes the style guide section on putting accessors to construct global objects on the PyMlirContext: this style fails to make good use of the new facility since it is often the only thing remaining needing an MlirContext.
• Moves Module parse/creation from mlir.ir.Context to static methods on mlir.ir.Module.
• Moves Context.create_operation to a static Operation.create method.
• Moves Type parsing from mlir.ir.Context to static methods on mlir.ir.Type.
• Moves Attribute parsing from mlir.ir.Context to static methods on mlir.ir.Attribute.
• Move Location factory methods from mlir.ir.Context to static methods on mlir.ir.Location.
• Refactors the std dialect fake "ODS" generated code to take advantage of the new scheme.

[stellaraccident]

Add error description to types.

[stellaraccident]

Update desc.

[mehdi_amini]

Looks great! The DefaultingPyLocation (and similar for Context) with the "caster" is fitting pretty neatly here!

I only left very minor inline comments.

mlir/docs/Bindings/Python.md

143

I don't quite get the C++ analogy here?

154

Nit: as a follow up (or a pre-commit if you prefer), can you run this file through mdformat or something like this to wraps these really long paragraph?

mlir/lib/Bindings/Python/IRModules.cpp

564

Great message! I really like when we're providing user with hints to the solution instead of just shouting "missing context".

592

Can you add a comment in what is the logic you're applying here?

737

Nit: spurious empty line?

2325

Seems like this new line break shouldn't be needed?

2460

This is a nicer place for these methods compared to being on the context!

2653

mlir/lib/Bindings/Python/IRModules.h

122

Can you rename this getTopOfStack? It'll be more clear for the callers. (feel free to do it in a NFC commit separately)

[zhanghb97]

mlir/lib/Bindings/Python/IRModules.h

96

I don't get what 'k' here means (also the 'k' in the previous Docstring name), is it a special naming convention?

[stellaraccident]

Comments and rebase.

[stellaraccident]

In D90547#2367420, @mehdi_amini wrote:

Looks great! The DefaultingPyLocation (and similar for Context) with the "caster" is fitting pretty neatly here!

I only left very minor inline comments.

Thanks - I was really pleased with how it turned out (once I actually got through to the end - it was a lot of untangling).

mlir/docs/Bindings/Python.md

143

I just removed that part.

Fwiw, I was referring to how when doing recursive template meta-programming in C++, you typically match and consume arguments from the left, so if setting yourself up for that, you want to prefix common arguments. Not particularly relevant to this doc, though.

154

I'll format and land a followon NFC so that the diff stays clean on this one.

mlir/lib/Bindings/Python/IRModules.cpp

564

:)

2460

Agreed - I was really happy when that worked out like this.

mlir/lib/Bindings/Python/IRModules.h

96

The 'k' prefix is a common feature of many C++ style guides, and I believe, does show up in LLVM code. However, the official recommendation is to not use it, so removed.

[stellaraccident]

Alex, I'll be off-site away from my workstation tomorrow, so went ahead and pushed with Mehdi's review. If you have comments, feel free and I'll address in a followup.

[mehdi_amini]

mlir/lib/Bindings/Python/IRModules.h

96

It is the google style guide creeping up in upstream patches, since there is no convention in LLVM for constant I believe we never settled on any given style

mlir/docs/Bindings/Python.md

 
 To start with the `mlir/__init__.py` loader shim can be very simple and scale to
 future need:
 
 ```python
 from _mlir import *
 ```
 
-### Limited use of globals
-
-For normal operations, parent-child constructor relationships are realized with
-constructor methods on a parent class as opposed to requiring
-invocation/creation from a global symbol.
-
-For example, consider two code fragments:
-
-```python
-
-op = build_my_op()
-
-region = mlir.Region(op)
-
-```
-
-vs
-
-```python
-
-op = build_my_op()
-
-region = op.new_region()
-
-```
-
-For tightly coupled data structures like `Operation`, the latter is generally
-preferred because:
-
-* It is syntactically less possible to create something that is going to access
-  illegal memory (less error handling in the bindings, less testing, etc).
-
-* It reduces the global-API surface area for creating related entities. This
-  makes it more likely that if constructing IR based on an Operation instance of
-  unknown providence, receiving code can just call methods on it to do what they
-  want versus needing to reach back into the global namespace and find the right
-  `Region` class.
-
-* It leaks fewer things that are in place for C++ convenience (i.e. default
-  constructors to invalid instances).
-
 ### Use the C-API
 
 The Python APIs should seek to layer on top of the C-API to the degree possible.
 Especially for the core, dialect-independent parts, such a binding enables
 packaging decisions that would be difficult or impossible if spanning a C++ ABI
 boundary. In addition, factoring in this way side-steps some very difficult
 issues that arise when combining RTTI-based modules (which pybind derived things
 are) with non-RTTI polymorphic C++ code (the default compilation mode of LLVM).
 
 
 ### Ownership in the Core IR
 
 There are several top-level types in the core IR that are strongly owned by their python-side reference:
 
 * `PyContext` (`mlir.ir.Context`)
 * `PyModule` (`mlir.ir.Module`)
 * `PyOperation` (`mlir.ir.Operation`) - but with caveats
 
 All other objects are dependent. All objects maintain a back-reference (keep-alive) to their closest containing top-level object. Further, dependent objects fall into two categories: a) uniqued (which live for the life-time of the context) and b) mutable. Mutable objects need additional machinery for keeping track of when the C++ instance that backs their Python object is no longer valid (typically due to some specific mutation of the IR, deletion, or bulk operation).
 
+### Optionality and argument ordering in the Core IR
+
+The following types support being bound to the current thread as a context manager:
+
+* `PyLocation` (`loc: mlir.ir.Location = None`)
+* `PyInsertionPoint` (`ip: mlir.ir.InsertionPoint = None`)
+* `PyMlirContext` (`context: mlir.ir.Context = None`)
+
+In order to support composability of function arguments, when these types appear as arguments, they should always be the last and appear in the above order and with the given names (which is generally the order in which they are expected to need to be expressed explicitly in special cases) as necessary. Each should carry a default value of `py::none()` and use either a manual or automatic conversion for resolving either with the explicit value or a value from the thread context manager (i.e. `DefaultingPyMlirContext` or `DefaultingPyLocation`).
+
+The rationale for this is that unlike C++, where arguments to the *left* are the most composable via templating, in Python, trailing keyword arguments to the *right* are the most composable, enabling a variety of strategies such as kwarg passthrough, default values, etc. Keeping function signatures composable increases the chances that interesting DSLs and higher level APIs can be constructed without a lot of exotic boilerplate.
+
+Used consistently, this enables a style of IR construction that rarely needs to use explicit contexts, locations, or insertion points but is free to do so when extra control is needed.
+
 #### Operation hierarchy
 
 As mentioned above, `PyOperation` is special because it can exist in either a top-level or dependent state. The life-cycle is unidirectional: operations can be created detached (top-level) and once added to another operation, they are then dependent for the remainder of their lifetime. The situation is more complicated when considering construction scenarios where an operation is added to a transitive parent that is still detached, necessitating further accounting at such transition points (i.e. all such added children are initially added to the IR with a parent of their outer-most detached operation, but then once it is added to an attached operation, they need to be re-parented to the containing module).
 
 Due to the validity and parenting accounting needs, `PyOperation` is the owner for regions and blocks and needs to be a top-level type that we can count on not aliasing. This let's us do things like selectively invalidating instances when mutations occur without worrying that there is some alias to the same operation in the hierarchy. Operations are also the only entity that are allowed to be in a detached state, and they are interned at the context level so that there is never more than one Python `mlir.ir.Operation` object for a unique `MlirOperation`, regardless of how it is obtained.
 
 The C/C++ API allows for Region/Block to also be detached, but it simplifies the ownership model a lot to eliminate that possibility in this API, allowing the Region/Block to be completely dependent on its owning operation for accounting. The aliasing of Python `Region`/`Block` instances to underlying `MlirRegion`/`MlirBlock` is considered benign and these objects are not interned in the context (unlike operations).
 
 If we ever want to re-introduce detached regions/blocks, we could do so with new "DetachedRegion" class or similar and also avoid the complexity of accounting. With the way it is now, we can avoid having a global live list for regions and blocks. We may end up needing an op-local one at some point TBD, depending on how hard it is to guarantee how mutations interact with their Python peer objects. We can cross that bridge easily when we get there.
 
 Module, when used purely from the Python API, can't alias anyway, so we can use it as a top-level ref type without a live-list for interning. If the API ever changes such that this cannot be guaranteed (i.e. by letting you marshal a native-defined Module in), then there would need to be a live table for it too.
 
 ## Style
 
 In general, for the core parts of MLIR, the Python bindings should be largely
 isomorphic with the underlying C++ structures. However, concessions are made

mlir/lib/Bindings/Python/IRModules.h

 //===- IRModules.h - IR Submodules of pybind module -----------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef MLIR_BINDINGS_PYTHON_IRMODULES_H
 #define MLIR_BINDINGS_PYTHON_IRMODULES_H
 
 #include <vector>
 
-#include <pybind11/pybind11.h>
+#include "PybindUtils.h"
 
 #include "mlir-c/IR.h"
 #include "llvm/ADT/DenseMap.h"
 
 namespace mlir {
 namespace python {
 
 class PyBlock;
 class PyInsertionPoint;
 class PyLocation;
+class DefaultingPyLocation;
 class PyMlirContext;
+class DefaultingPyMlirContext;
 class PyModule;
 class PyOperation;
 class PyType;
 class PyValue;
 
 /// Template for a reference to a concrete type which captures a python
 /// reference to its underlying python object.
 template <typename T>
public:
   operator bool() const { return referrent && object; }
 
 private:
   T *referrent;
   pybind11::object object;
 };
 
 /// Tracks an entry in the thread context stack. New entries are pushed onto
-/// here for each with block that activates a new InsertionPoint or Context.
-/// Pushing either a context or an insertion point resets the other:
-///   - a new context activates a new entry with a null insertion point.
-///   - a new insertion point activates a new entry with the context that the
-///     insertion point is bound to.
+/// here for each with block that activates a new InsertionPoint, Context or
+/// Location.
+///
+/// Pushing either a Location or InsertionPoint also pushes its associated
+/// Context. Pushing a Context will not modify the Location or InsertionPoint
+/// unless if they are from a different context, in which case, they are
+/// cleared.
 class PyThreadContextEntry {
 public:
-  PyThreadContextEntry(pybind11::object context,
-                       pybind11::object insertionPoint)
-      : context(std::move(context)), insertionPoint(std::move(insertionPoint)) {
-  }
+  enum class FrameKind {
+    kContext,
+    kInsertionPoint,
+    kLocation,
+  };
+
+  PyThreadContextEntry(FrameKind frameKind, pybind11::object context,
+                       pybind11::object insertionPoint,
+                       pybind11::object location)
+      : context(std::move(context)), insertionPoint(std::move(insertionPoint)),
+        location(std::move(location)), frameKind(frameKind) {}
 
   /// Gets the top of stack context and return nullptr if not defined.
-  /// If required is true and there is no default, a nice user-facing exception
-  /// is raised.
-  static PyMlirContext *getDefaultContext(bool required);
+  static PyMlirContext *getDefaultContext();
 
   /// Gets the top of stack insertion point and return nullptr if not defined.
-  /// If required is true and there is no default, a nice user-facing exception
-  /// is raised.
-  static PyInsertionPoint *getDefaultInsertionPoint(bool required);
+  static PyInsertionPoint *getDefaultInsertionPoint();
+
+  /// Gets the top of stack location and returns nullptr if not defined.
+  static PyLocation *getDefaultLocation();
 
   PyMlirContext *getContext();
   PyInsertionPoint *getInsertionPoint();
+  PyLocation *getLocation();
+  FrameKind getFrameKind() { return frameKind; }
 
   /// Stack management.
   static PyThreadContextEntry *getTos();
-  static void push(pybind11::object context, pybind11::object insertionPoint);
+  static pybind11::object pushContext(PyMlirContext &context);
+  static void popContext(PyMlirContext &context);
+  static pybind11::object pushInsertionPoint(PyInsertionPoint &insertionPoint);
+  static void popInsertionPoint(PyInsertionPoint &insertionPoint);
+  static pybind11::object pushLocation(PyLocation &location);
+  static void popLocation(PyLocation &location);
 
   /// Gets the thread local stack.
   static std::vector<PyThreadContextEntry> &getStack();
 
 private:
+  static void push(FrameKind frameKind, pybind11::object context,
+                   pybind11::object insertionPoint, pybind11::object location);
+
   /// An object reference to the PyContext.
   pybind11::object context;
   /// An object reference to the current insertion point.
   pybind11::object insertionPoint;
+  /// An object reference to the current location.
+  pybind11::object location;
+  // The kind of push that was performed.
+  FrameKind frameKind;
 };
 
 /// Wrapper around MlirContext.
 using PyMlirContextRef = PyObjectRef<PyMlirContext>;
 class PyMlirContext {
 public:
   PyMlirContext() = delete;
   PyMlirContext(const PyMlirContext &) = delete;
public:
   /// Gets the count of live operations associated with this context.
   /// Used for testing.
   size_t getLiveOperationCount();
 
   /// Gets the count of live modules associated with this context.
   /// Used for testing.
   size_t getLiveModuleCount();
 
-  /// Creates an operation. See corresponding python docstring.
-  pybind11::object
-  createOperation(std::string name, PyLocation location,
-                  llvm::Optional<std::vector<PyValue *>> operands,
-                  llvm::Optional<std::vector<PyType *>> results,
-                  llvm::Optional<pybind11::dict> attributes,
-                  llvm::Optional<std::vector<PyBlock *>> successors,
-                  int regions);
+  /// Enter and exit the context manager.
+  pybind11::object contextEnter();
+  void contextExit(pybind11::object excType, pybind11::object excVal,
+                   pybind11::object excTb);
 
 private:
   PyMlirContext(MlirContext context);
   // Interns the mapping of live MlirContext::ptr to PyMlirContext instances,
   // preserving the relationship that an MlirContext maps to a single
   // PyMlirContext wrapper. This could be replaced in the future with an
   // extension mechanism on the MlirContext for stashing user pointers.
   // Note that this holds a handle, which does not imply ownership.
using LiveOperationMap =
       llvm::DenseMap<void *, std::pair<pybind11::handle, PyOperation *>>;
   LiveOperationMap liveOperations;
 
   MlirContext context;
   friend class PyModule;
   friend class PyOperation;
 };
 
+/// Used in function arguments when None should resolve to the current context
+/// manager set instance.
+class DefaultingPyMlirContext
+    : public Defaulting<DefaultingPyMlirContext, PyMlirContext> {
+public:
+  using Defaulting::Defaulting;
+  static constexpr const char kTypeDescription[] =
+      "[ThreadContextAware] mlir.ir.Context";
+  static PyMlirContext &resolve();
+};
+
 /// Base class for all objects that directly or indirectly depend on an
 /// MlirContext. The lifetime of the context will extend at least to the
 /// lifetime of these instances.
 /// Immutable objects that depend on a context extend this directly.
 class BaseContextObject {
 public:
   BaseContextObject(PyMlirContextRef ref) : contextRef(std::move(ref)) {
     assert(this->contextRef &&
private:
   pybind11::object descriptor;
 };
 
 /// Wrapper around an MlirLocation.
 class PyLocation : public BaseContextObject {
 public:
   PyLocation(PyMlirContextRef contextRef, MlirLocation loc)
       : BaseContextObject(std::move(contextRef)), loc(loc) {}
+
+  /// Enter and exit the context manager.
+  pybind11::object contextEnter();
+  void contextExit(pybind11::object excType, pybind11::object excVal,
+                   pybind11::object excTb);
+
   MlirLocation loc;
 };
 
+/// Used in function arguments when None should resolve to the current context
+/// manager set instance.
+class DefaultingPyLocation
+    : public Defaulting<DefaultingPyLocation, PyLocation> {
+public:
+  using Defaulting::Defaulting;
+  static constexpr const char kTypeDescription[] =
+      "[ThreadContextAware] mlir.ir.Location";
+  static PyLocation &resolve();
+};
+
 /// Wrapper around MlirModule.
 /// This is the top-level, user-owned object that contains regions/ops/blocks.
 class PyModule;
 using PyModuleRef = PyObjectRef<PyModule>;
 class PyModule : public BaseContextObject {
 public:
   /// Returns a PyModule reference for the given MlirModule. This may return
   /// a pre-existing or new object.
public:
   /// Gets the owning block or raises an exception if the operation has no
   /// owning block.
   PyBlock getBlock();
 
   /// Gets the parent operation or raises an exception if the operation has
   /// no parent.
   PyOperationRef getParentOperation();
 
+  /// Creates an operation. See corresponding python docstring.
+  static pybind11::object
+  create(std::string name, llvm::Optional<std::vector<PyValue *>> operands,
+         llvm::Optional<std::vector<PyType *>> results,
+         llvm::Optional<pybind11::dict> attributes,
+         llvm::Optional<std::vector<PyBlock *>> successors, int regions,
+         DefaultingPyLocation location, pybind11::object ip);
+
 private:
   PyOperation(PyMlirContextRef contextRef, MlirOperation operation);
   static PyOperationRef createInstance(PyMlirContextRef contextRef,
                                        MlirOperation operation,
                                        pybind11::object parentKeepAlive);
 
   MlirOperation operation;
   pybind11::handle handle;
public:
   /// Inserts an operation.
   void insert(PyOperation &operation);
 
   /// Enter and exit the context manager.
   pybind11::object contextEnter();
   void contextExit(pybind11::object excType, pybind11::object excVal,
                    pybind11::object excTb);
 
+  PyBlock &getBlock() { return block; }
+
 private:
   // Trampoline constructor that avoids null initializing members while
   // looking up parents.
   PyInsertionPoint(PyBlock block, llvm::Optional<PyOperationRef> refOperation)
       : block(std::move(block)), refOperation(std::move(refOperation)) {}
 
   PyBlock block;
   llvm::Optional<PyOperationRef> refOperation;
private:
   MlirValue value;
 };
 
 void populateIRSubmodule(pybind11::module &m);
 
 } // namespace python
 } // namespace mlir
 
+namespace pybind11 {
+namespace detail {
+
+template <>
+struct type_caster<mlir::python::DefaultingPyMlirContext>
+    : MlirDefaultingCaster<mlir::python::DefaultingPyMlirContext> {};
+template <>
+struct type_caster<mlir::python::DefaultingPyLocation>
+    : MlirDefaultingCaster<mlir::python::DefaultingPyLocation> {};
+
+} // namespace detail
+} // namespace pybind11
+
 #endif // MLIR_BINDINGS_PYTHON_IRMODULES_H

mlir/lib/Bindings/Python/IRModules.cpp

 using namespace mlir::python;
 
 using llvm::SmallVector;
 
 //------------------------------------------------------------------------------
 // Docstrings (trivial, non-duplicated docstrings are included inline).
 //------------------------------------------------------------------------------
 
-static const char kContextCreateOperationDocstring[] =
-    R"(Creates a new operation.
+static const char kContextParseTypeDocstring[] =
+    R"(Parses the assembly form of a type.
 
-Args:
-  name: Operation name (e.g. "dialect.operation").
-  location: A Location object.
-  results: Sequence of Type representing op result types.
-  attributes: Dict of str:Attribute.
-  successors: List of Block for the operation's successors.
-  regions: Number of regions to create.
+Returns a Type object or raises a ValueError if the type cannot be parsed.
 
-Returns:
-  A new "detached" Operation object. Detached operations can be added
-  to blocks, which causes them to become "attached."
+See also: https://mlir.llvm.org/docs/LangRef/#type-system
 )";
 
-static const char kContextParseDocstring[] =
+static const char kContextGetFileLocationDocstring[] =
+    R"(Gets a Location representing a file, line and column)";
+
+static const char kModuleParseDocstring[] =
     R"(Parses a module's assembly format from a string.
 
 Returns a new MlirModule or raises a ValueError if the parsing fails.
 
 See also: https://mlir.llvm.org/docs/LangRef/
 )";
 
-static const char kContextParseTypeDocstring[] =
-    R"(Parses the assembly form of a type.
-
-Returns a Type object or raises a ValueError if the type cannot be parsed.
+static const char kOperationCreateDocstring[] =
+    R"(Creates a new operation.
 
-See also: https://mlir.llvm.org/docs/LangRef/#type-system
+Args:
+  name: Operation name (e.g. "dialect.operation").
+  results: Sequence of Type representing op result types.
+  attributes: Dict of str:Attribute.
+  successors: List of Block for the operation's successors.
+  regions: Number of regions to create.
+  location: A Location object (defaults to resolve from context manager).
+  ip: An InsertionPoint (defaults to resolve from context manager or set to
+    False to disable insertion, even with an insertion point set in the
+    context manager).
+Returns:
+  A new "detached" Operation object. Detached operations can be added
+  to blocks, which causes them to become "attached."
 )";
 
-static const char kContextGetUnknownLocationDocstring[] =
-    R"(Gets a Location representing an unknown location)";
-
-static const char kContextGetFileLocationDocstring[] =
-    R"(Gets a Location representing a file, line and column)";
-
 static const char kOperationPrintDocstring[] =
     R"(Prints the assembly form of the operation to a file like object.
 
 Args:
   file: The file like object to write to. Defaults to sys.stdout.
   binary: Whether to write bytes (True) or str (False). Defaults to False.
   large_elements_limit: Whether to elide elements attributes above this
     number of elements. Defaults to None (no limit).

 }
 
 size_t PyMlirContext::getLiveCount() { return getLiveContexts().size(); }
 
 size_t PyMlirContext::getLiveOperationCount() { return liveOperations.size(); }
 
 size_t PyMlirContext::getLiveModuleCount() { return liveModules.size(); }
 
-py::object PyMlirContext::createOperation(
-    std::string name, PyLocation location,
-    llvm::Optional<std::vector<PyValue *>> operands,
-    llvm::Optional<std::vector<PyType *>> results,
-    llvm::Optional<py::dict> attributes,
-    llvm::Optional<std::vector<PyBlock *>> successors, int regions) {
-  llvm::SmallVector<MlirValue, 4> mlirOperands;
-  llvm::SmallVector<MlirType, 4> mlirResults;
-  llvm::SmallVector<MlirBlock, 4> mlirSuccessors;
-  llvm::SmallVector<std::pair<std::string, MlirAttribute>, 4> mlirAttributes;
-
-  // General parameter validation.
-  if (regions < 0)
-    throw SetPyError(PyExc_ValueError, "number of regions must be >= 0");
-
-  // Unpack/validate operands.
-  if (operands) {
-    mlirOperands.reserve(operands->size());
-    for (PyValue *operand : *operands) {
-      if (!operand)
-        throw SetPyError(PyExc_ValueError, "operand value cannot be None");
-      mlirOperands.push_back(operand->get());
-    }
-  }
+pybind11::object PyMlirContext::contextEnter() {
+  return PyThreadContextEntry::pushContext(*this);
 
-  // Unpack/validate results.
-  if (results) {
-    mlirResults.reserve(results->size());
-    for (PyType *result : *results) {
-      // TODO: Verify result type originate from the same context.
-      if (!result)
-        throw SetPyError(PyExc_ValueError, "result type cannot be None");
-      mlirResults.push_back(result->type);
-    }
-  }
-  // Unpack/validate attributes.
-  if (attributes) {
-    mlirAttributes.reserve(attributes->size());
-    for (auto &it : *attributes) {
-
-      auto name = it.first.cast<std::string>();
-      auto &attribute = it.second.cast<PyAttribute &>();
-      // TODO: Verify attribute originates from the same context.
-      mlirAttributes.emplace_back(std::move(name), attribute.attr);
-    }
-  }
-  // Unpack/validate successors.
-  if (successors) {
-    llvm::SmallVector<MlirBlock, 4> mlirSuccessors;
-    mlirSuccessors.reserve(successors->size());
-    for (auto *successor : *successors) {
-      // TODO: Verify successor originate from the same context.
-      if (!successor)
-        throw SetPyError(PyExc_ValueError, "successor block cannot be None");
-      mlirSuccessors.push_back(successor->get());
-    }
-  }
+void PyMlirContext::contextExit(pybind11::object excType,
+                                pybind11::object excVal,
+                                pybind11::object excTb) {
+  PyThreadContextEntry::popContext(*this);
 
-  // Apply unpacked/validated to the operation state. Beyond this
-  // point, exceptions cannot be thrown or else the state will leak.
-  MlirOperationState state = mlirOperationStateGet(name.c_str(), location.loc);
-  if (!mlirOperands.empty())
-    mlirOperationStateAddOperands(&state, mlirOperands.size(),
-                                  mlirOperands.data());
-  if (!mlirResults.empty())
-    mlirOperationStateAddResults(&state, mlirResults.size(),
-                                 mlirResults.data());
-  if (!mlirAttributes.empty()) {
-    // Note that the attribute names directly reference bytes in
-    // mlirAttributes, so that vector must not be changed from here
-    // on.
-    llvm::SmallVector<MlirNamedAttribute, 4> mlirNamedAttributes;
-    mlirNamedAttributes.reserve(mlirAttributes.size());
-    for (auto &it : mlirAttributes)
-      mlirNamedAttributes.push_back(
-          mlirNamedAttributeGet(it.first.c_str(), it.second));
-    mlirOperationStateAddAttributes(&state, mlirNamedAttributes.size(),
-                                    mlirNamedAttributes.data());
-  }
-  if (!mlirSuccessors.empty())
-    mlirOperationStateAddSuccessors(&state, mlirSuccessors.size(),
-                                    mlirSuccessors.data());
-  if (regions) {
-    llvm::SmallVector<MlirRegion, 4> mlirRegions;
-    mlirRegions.resize(regions);
-    for (int i = 0; i < regions; ++i)
-      mlirRegions[i] = mlirRegionCreate();
-    mlirOperationStateAddOwnedRegions(&state, mlirRegions.size(),
-                                      mlirRegions.data());
+PyMlirContext &DefaultingPyMlirContext::resolve() {
+  PyMlirContext *context = PyThreadContextEntry::getDefaultContext();
+  if (!context) {
+    throw SetPyError(
+        PyExc_RuntimeError,
+        "An MLIR function requires a Context but none was provided in the call "
+        "or from the surrounding environment. Either pass to the function with "
+        "a 'context=' argument or establish a default using 'with Context():'");
   }
-
-  // Construct the operation.
-  MlirOperation operation = mlirOperationCreate(&state);
-  PyOperationRef created = PyOperation::createDetached(getRef(), operation);
-
-  // InsertPoint active?
-  PyInsertionPoint *ip =
-      PyThreadContextEntry::getDefaultInsertionPoint(/*required=*/false);
-  if (ip)
-    ip->insert(*created.get());
-
-  return created.releaseObject();
+  return *context;
 }
 
 //------------------------------------------------------------------------------
 // PyThreadContextEntry management
 //------------------------------------------------------------------------------
 
 std::vector<PyThreadContextEntry> &PyThreadContextEntry::getStack() {
   static thread_local std::vector<PyThreadContextEntry> stack;
   return stack;
 }
 
 PyThreadContextEntry *PyThreadContextEntry::getTos() {
   auto &stack = getStack();
   if (stack.empty())
     return nullptr;
   return &stack.back();
 }
 
-void PyThreadContextEntry::push(pybind11::object context,
-                                pybind11::object insertionPoint) {
+void PyThreadContextEntry::push(FrameKind frameKind, py::object context,
+                                py::object insertionPoint,
+                                py::object location) {
   auto &stack = getStack();
-  stack.emplace_back(std::move(context), std::move(insertionPoint));
+  stack.emplace_back(frameKind, std::move(context), std::move(insertionPoint),
+                     std::move(location));
+
+  if (stack.size() > 1) {
+    auto &prev = *(stack.rbegin() + 1);
+    auto &current = stack.back();
+    if (current.context.is(prev.context)) {
+      // Default non-context objects from the previous entry.
+      if (!current.insertionPoint)
+        current.insertionPoint = prev.insertionPoint;
+      if (!current.location)
+        current.location = prev.location;
+    }
+  }
 }
 
 PyMlirContext *PyThreadContextEntry::getContext() {
   if (!context)
     return nullptr;
   return py::cast<PyMlirContext *>(context);
 }
 
 PyInsertionPoint *PyThreadContextEntry::getInsertionPoint() {
   if (!insertionPoint)
     return nullptr;
   return py::cast<PyInsertionPoint *>(insertionPoint);
 }
 
-PyMlirContext *PyThreadContextEntry::getDefaultContext(bool required) {
+PyLocation *PyThreadContextEntry::getLocation() {
+  if (!location)
+    return nullptr;
+  return py::cast<PyLocation *>(location);
+}
+
+PyMlirContext *PyThreadContextEntry::getDefaultContext() {
   auto *tos = getTos();
-  PyMlirContext *context = tos ? tos->getContext() : nullptr;
-  if (required && !context) {
-    throw SetPyError(
-        PyExc_RuntimeError,
-        "A default context is required for this call but is not provided. "
-        "Establish a default by surrounding the code with "
-        "'with context:'");
-  }
-  return context;
+  return tos ? tos->getContext() : nullptr;
+
+PyInsertionPoint *PyThreadContextEntry::getDefaultInsertionPoint() {
+  auto *tos = getTos();
+  return tos ? tos->getInsertionPoint() : nullptr;
 }
 
-PyInsertionPoint *
-PyThreadContextEntry::getDefaultInsertionPoint(bool required) {
+PyLocation *PyThreadContextEntry::getDefaultLocation() {
   auto *tos = getTos();
-  PyInsertionPoint *ip = tos ? tos->getInsertionPoint() : nullptr;
-  if (required && !ip)
+  return tos ? tos->getLocation() : nullptr;
+}
+
+py::object PyThreadContextEntry::pushContext(PyMlirContext &context) {
+  py::object contextObj = py::cast(context);
+  push(FrameKind::kContext, /*context=*/contextObj,
+       /*insertionPoint=*/py::object(),
+       /*location=*/py::object());
+  return contextObj;
+}
+
+void PyThreadContextEntry::popContext(PyMlirContext &context) {
+  auto &stack = getStack();
+  if (stack.empty())
+    throw SetPyError(PyExc_RuntimeError, "Unbalanced Context enter/exit");
+  auto &tos = stack.back();
+  if (tos.frameKind != FrameKind::kContext && tos.getContext() != &context)
+    throw SetPyError(PyExc_RuntimeError, "Unbalanced Context enter/exit");
+  stack.pop_back();
+}
+
+py::object
+PyThreadContextEntry::pushInsertionPoint(PyInsertionPoint &insertionPoint) {
+  py::object contextObj =
+      insertionPoint.getBlock().getParentOperation()->getContext().getObject();
+  py::object insertionPointObj = py::cast(insertionPoint);
+  push(FrameKind::kInsertionPoint,
+       /*context=*/contextObj,
+       /*insertionPoint=*/insertionPointObj,
+       /*location=*/py::object());
+  return insertionPointObj;
+}
+
+void PyThreadContextEntry::popInsertionPoint(PyInsertionPoint &insertionPoint) {
+  auto &stack = getStack();
+  if (stack.empty())
     throw SetPyError(PyExc_RuntimeError,
-                     "A default insertion point is required for this call but "
-                     "is not provided. "
-                     "Establish a default by surrounding the code with "
-                     "'with InsertionPoint(...):'");
-  return ip;
+                     "Unbalanced InsertionPoint enter/exit");
+  auto &tos = stack.back();
+  if (tos.frameKind != FrameKind::kInsertionPoint &&
+      tos.getInsertionPoint() != &insertionPoint)
+    throw SetPyError(PyExc_RuntimeError,
+                     "Unbalanced InsertionPoint enter/exit");
+  stack.pop_back();
+}
+
+py::object PyThreadContextEntry::pushLocation(PyLocation &location) {
+  py::object contextObj = location.getContext().getObject();
+  py::object locationObj = py::cast(location);
+  push(FrameKind::kLocation, /*context=*/contextObj,
+       /*insertionPoint=*/py::object(),
+       /*location=*/locationObj);
+  return locationObj;
+}
+
+void PyThreadContextEntry::popLocation(PyLocation &location) {
+  auto &stack = getStack();
+  if (stack.empty())
+    throw SetPyError(PyExc_RuntimeError, "Unbalanced Location enter/exit");
+  auto &tos = stack.back();
+  if (tos.frameKind != FrameKind::kLocation && tos.getLocation() != &location)
+    throw SetPyError(PyExc_RuntimeError, "Unbalanced Location enter/exit");
+  stack.pop_back();
 }
 
 //------------------------------------------------------------------------------
 // PyDialect, PyDialectDescriptor, PyDialects
 //------------------------------------------------------------------------------
 
 MlirDialect PyDialects::getDialectForKey(const std::string &key,
                                          bool attrError) {
   // If the "std" dialect was asked for, substitute the empty namespace :(
   static const std::string emptyKey;
   const std::string *canonKey = key == "std" ? &emptyKey : &key;
   MlirDialect dialect = mlirContextGetOrLoadDialect(
       getContext()->get(), {canonKey->data(), canonKey->size()});
   if (mlirDialectIsNull(dialect)) {
     throw SetPyError(attrError ? PyExc_AttributeError : PyExc_IndexError,
                      llvm::Twine("Dialect '") + key + "' not found");
   }
   return dialect;
 }
 
 //------------------------------------------------------------------------------
+// PyLocation
+//------------------------------------------------------------------------------
+
+py::object PyLocation::contextEnter() {
+  return PyThreadContextEntry::pushLocation(*this);
+}
+
+void PyLocation::contextExit(py::object excType, py::object excVal,
+                             py::object excTb) {
+  PyThreadContextEntry::popLocation(*this);
+}
+
+PyLocation &DefaultingPyLocation::resolve() {
+  auto *location = PyThreadContextEntry::getDefaultLocation();
+  if (!location) {
+    throw SetPyError(
+        PyExc_RuntimeError,
+        "An MLIR function requires a Location but none was provided in the "
+
+        "call or from the surrounding environment. Either pass to the function "
+        "with a 'loc=' argument or establish a default using 'with loc:'");
+  }
+  return *location;
+}
+
+//------------------------------------------------------------------------------
 // PyModule
 //------------------------------------------------------------------------------
 
 PyModule::PyModule(PyMlirContextRef contextRef, MlirModule module)
     : BaseContextObject(std::move(contextRef)), module(module) {}
 
 PyModule::~PyModule() {
   py::gil_scoped_acquire acquire;

 
 PyBlock PyOperation::getBlock() {
   PyOperationRef parentOperation = getParentOperation();
   MlirBlock block = mlirOperationGetBlock(get());
   assert(!mlirBlockIsNull(block) && "Attached operation has null parent");
   return PyBlock{std::move(parentOperation), block};
 }
 
+py::object PyOperation::create(
+    std::string name, llvm::Optional<std::vector<PyValue *>> operands,
+    llvm::Optional<std::vector<PyType *>> results,
+    llvm::Optional<py::dict> attributes,
+    llvm::Optional<std::vector<PyBlock *>> successors, int regions,
+    DefaultingPyLocation location, py::object maybeIp) {
+  llvm::SmallVector<MlirValue, 4> mlirOperands;
+  llvm::SmallVector<MlirType, 4> mlirResults;
+  llvm::SmallVector<MlirBlock, 4> mlirSuccessors;
+  llvm::SmallVector<std::pair<std::string, MlirAttribute>, 4> mlirAttributes;
+
+  // General parameter validation.
+  if (regions < 0)
+    throw SetPyError(PyExc_ValueError, "number of regions must be >= 0");
+
+  // Unpack/validate operands.
+  if (operands) {
+    mlirOperands.reserve(operands->size());
+    for (PyValue *operand : *operands) {
+      if (!operand)
+        throw SetPyError(PyExc_ValueError, "operand value cannot be None");
+      mlirOperands.push_back(operand->get());
+    }
+  }
+
+  // Unpack/validate results.
+  if (results) {
+    mlirResults.reserve(results->size());
+    for (PyType *result : *results) {
+      // TODO: Verify result type originate from the same context.
+      if (!result)
+        throw SetPyError(PyExc_ValueError, "result type cannot be None");
+      mlirResults.push_back(result->type);
+    }
+  }
+  // Unpack/validate attributes.
+  if (attributes) {
+    mlirAttributes.reserve(attributes->size());
+    for (auto &it : *attributes) {
+
+      auto name = it.first.cast<std::string>();
+      auto &attribute = it.second.cast<PyAttribute &>();
+      // TODO: Verify attribute originates from the same context.
+      mlirAttributes.emplace_back(std::move(name), attribute.attr);
+    }
+  }
+  // Unpack/validate successors.
+  if (successors) {
+    llvm::SmallVector<MlirBlock, 4> mlirSuccessors;
+    mlirSuccessors.reserve(successors->size());
+    for (auto *successor : *successors) {
+      // TODO: Verify successor originate from the same context.
+      if (!successor)
+        throw SetPyError(PyExc_ValueError, "successor block cannot be None");
+      mlirSuccessors.push_back(successor->get());
+    }
+  }
+
+  // Apply unpacked/validated to the operation state. Beyond this
+  // point, exceptions cannot be thrown or else the state will leak.
+  MlirOperationState state = mlirOperationStateGet(name.c_str(), location->loc);
+  if (!mlirOperands.empty())
+    mlirOperationStateAddOperands(&state, mlirOperands.size(),
+                                  mlirOperands.data());
+  if (!mlirResults.empty())
+    mlirOperationStateAddResults(&state, mlirResults.size(),
+                                 mlirResults.data());
+  if (!mlirAttributes.empty()) {
+    // Note that the attribute names directly reference bytes in
+    // mlirAttributes, so that vector must not be changed from here
+    // on.
+    llvm::SmallVector<MlirNamedAttribute, 4> mlirNamedAttributes;
+    mlirNamedAttributes.reserve(mlirAttributes.size());
+    for (auto &it : mlirAttributes)
+      mlirNamedAttributes.push_back(
+          mlirNamedAttributeGet(it.first.c_str(), it.second));
+    mlirOperationStateAddAttributes(&state, mlirNamedAttributes.size(),
+                                    mlirNamedAttributes.data());
+  }
+  if (!mlirSuccessors.empty())
+    mlirOperationStateAddSuccessors(&state, mlirSuccessors.size(),
+                                    mlirSuccessors.data());
+  if (regions) {
+    llvm::SmallVector<MlirRegion, 4> mlirRegions;
+    mlirRegions.resize(regions);
+    for (int i = 0; i < regions; ++i)
+      mlirRegions[i] = mlirRegionCreate();
+    mlirOperationStateAddOwnedRegions(&state, mlirRegions.size(),
+                                      mlirRegions.data());
+  }
+
+  // Construct the operation.
+  MlirOperation operation = mlirOperationCreate(&state);
+  PyOperationRef created =
+      PyOperation::createDetached(location->getContext(), operation);
+
+  // InsertPoint active?
+  if (!maybeIp.is(py::cast(false))) {
+    PyInsertionPoint *ip;
+    if (maybeIp.is_none()) {
+      ip = PyThreadContextEntry::getDefaultInsertionPoint();
+    } else {
+      ip = py::cast<PyInsertionPoint *>(maybeIp);
+    }
+    if (ip)
+      ip->insert(*created.get());
+  }
+
+  return created.releaseObject();
+}
+
 PyOpView::PyOpView(py::object operation)
     : operationObject(std::move(operation)),
       operation(py::cast<PyOperation *>(this->operationObject)) {}
 
 py::object PyOpView::createRawSubclass(py::object userClass) {
   // This is... a little gross. The typical pattern is to have a pure python
   // class that extends OpView like:
   //   class AddFOp(_cext.ir.OpView):
PyInsertionPoint PyInsertionPoint::atBlockTerminator(PyBlock &block) {
   if (mlirOperationIsNull(terminator))
     throw SetPyError(PyExc_ValueError, "Block has no terminator");
   PyOperationRef terminatorOpRef = PyOperation::forOperation(
       block.getParentOperation()->getContext(), terminator);
   return PyInsertionPoint{block, std::move(terminatorOpRef)};
 }
 
 py::object PyInsertionPoint::contextEnter() {
-  auto context = block.getParentOperation()->getContext().getObject();
-  py::object self = py::cast(this);
-  PyThreadContextEntry::push(/*context=*/std::move(context),
-                             /*insertionPoint=*/self);
-  return self;
+  return PyThreadContextEntry::pushInsertionPoint(*this);
 }
 
 void PyInsertionPoint::contextExit(pybind11::object excType,
                                    pybind11::object excVal,
                                    pybind11::object excTb) {
-  auto &stack = PyThreadContextEntry::getStack();
-  if (stack.empty())
-    throw SetPyError(PyExc_RuntimeError,
-                     "Unbalanced insertion point enter/exit");
-  auto &tos = stack.back();
-  PyInsertionPoint *current = tos.getInsertionPoint();
-  if (current != this)
-    throw SetPyError(PyExc_RuntimeError,
-                     "Unbalanced insertion point enter/exit");
-  stack.pop_back();
+  PyThreadContextEntry::popInsertionPoint(*this);
 }
 
 //------------------------------------------------------------------------------
 // PyAttribute.
 //------------------------------------------------------------------------------
 
 bool PyAttribute::operator==(const PyAttribute &other) {
   return mlirAttributeEqual(attr, other.attr);

 public:
   static constexpr IsAFunctionTy isaFunction = mlirAttributeIsAFloat;
   static constexpr const char *pyClassName = "FloatAttr";
   using PyConcreteAttribute::PyConcreteAttribute;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        // TODO: Make the location optional and create a default location.
-        [](PyType &type, double value, PyLocation &loc) {
+        [](PyType &type, double value, DefaultingPyLocation loc) {
           MlirAttribute attr =
-              mlirFloatAttrDoubleGetChecked(type.type, value, loc.loc);
+              mlirFloatAttrDoubleGetChecked(type.type, value, loc->loc);
           // TODO: Rework error reporting once diagnostic engine is exposed
           // in C API.
           if (mlirAttributeIsNull(attr)) {
             throw SetPyError(PyExc_ValueError,
                              llvm::Twine("invalid '") +
                                  py::repr(py::cast(type)).cast<std::string>() +
                                  "' and expected floating point type.");
           }
           return PyFloatAttribute(type.getContext(), attr);
         },
-        py::arg("type"), py::arg("value"), py::arg("loc"),
+        py::arg("type"), py::arg("value"), py::arg("loc") = py::none(),
         "Gets an uniqued float point attribute associated to a type");
     c.def_static(
         "get_f32",
-        [](PyMlirContext &context, double value) {
+        [](double value, DefaultingPyMlirContext context) {
           MlirAttribute attr = mlirFloatAttrDoubleGet(
-              context.get(), mlirF32TypeGet(context.get()), value);
-          return PyFloatAttribute(context.getRef(), attr);
+              context->get(), mlirF32TypeGet(context->get()), value);
+          return PyFloatAttribute(context->getRef(), attr);
         },
-        py::arg("context"), py::arg("value"),
+        py::arg("value"), py::arg("context") = py::none(),
         "Gets an uniqued float point attribute associated to a f32 type");
     c.def_static(
         "get_f64",
-        [](PyMlirContext &context, double value) {
+        [](double value, DefaultingPyMlirContext context) {
           MlirAttribute attr = mlirFloatAttrDoubleGet(
-              context.get(), mlirF64TypeGet(context.get()), value);
-          return PyFloatAttribute(context.getRef(), attr);
+              context->get(), mlirF64TypeGet(context->get()), value);
+          return PyFloatAttribute(context->getRef(), attr);
         },
-        py::arg("context"), py::arg("value"),
+        py::arg("value"), py::arg("context") = py::none(),
         "Gets an uniqued float point attribute associated to a f64 type");
     c.def_property_readonly(
         "value",
         [](PyFloatAttribute &self) {
           return mlirFloatAttrGetValueDouble(self.attr);
         },
         "Returns the value of the float point attribute");
   }

 public:
   static constexpr IsAFunctionTy isaFunction = mlirAttributeIsABool;
   static constexpr const char *pyClassName = "BoolAttr";
   using PyConcreteAttribute::PyConcreteAttribute;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context, bool value) {
-          MlirAttribute attr = mlirBoolAttrGet(context.get(), value);
-          return PyBoolAttribute(context.getRef(), attr);
+        [](bool value, DefaultingPyMlirContext context) {
+          MlirAttribute attr = mlirBoolAttrGet(context->get(), value);
+          return PyBoolAttribute(context->getRef(), attr);
         },
-        py::arg("context"), py::arg("value"), "Gets an uniqued bool attribute");
+        py::arg("value"), py::arg("context") = py::none(),
+        "Gets an uniqued bool attribute");
     c.def_property_readonly(
         "value",
         [](PyBoolAttribute &self) { return mlirBoolAttrGetValue(self.attr); },
         "Returns the value of the bool attribute");
   }
 };
 
 class PyStringAttribute : public PyConcreteAttribute<PyStringAttribute> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirAttributeIsAString;
   static constexpr const char *pyClassName = "StringAttr";
   using PyConcreteAttribute::PyConcreteAttribute;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context, std::string value) {
+        [](std::string value, DefaultingPyMlirContext context) {
           MlirAttribute attr =
-              mlirStringAttrGet(context.get(), value.size(), &value[0]);
-          return PyStringAttribute(context.getRef(), attr);
+              mlirStringAttrGet(context->get(), value.size(), &value[0]);
+          return PyStringAttribute(context->getRef(), attr);
         },
+        py::arg("value"), py::arg("context") = py::none(),
         "Gets a uniqued string attribute");
     c.def_static(
         "get_typed",
         [](PyType &type, std::string value) {
           MlirAttribute attr =
               mlirStringAttrTypedGet(type.type, value.size(), &value[0]);
           return PyStringAttribute(type.getContext(), attr);
         },

 // TODO: Support construction of string elements.
 class PyDenseElementsAttribute
     : public PyConcreteAttribute<PyDenseElementsAttribute> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirAttributeIsADenseElements;
   static constexpr const char *pyClassName = "DenseElementsAttr";
   using PyConcreteAttribute::PyConcreteAttribute;
 
-  static PyDenseElementsAttribute getFromBuffer(PyMlirContext &contextWrapper,
-                                                py::buffer array,
-                                                bool signless) {
+  static PyDenseElementsAttribute
+  getFromBuffer(py::buffer array, bool signless,
+                DefaultingPyMlirContext contextWrapper) {
     // Request a contiguous view. In exotic cases, this will cause a copy.
     int flags = PyBUF_C_CONTIGUOUS | PyBUF_FORMAT;
     Py_buffer *view = new Py_buffer();
     if (PyObject_GetBuffer(array.ptr(), view, flags) != 0) {
       delete view;
       throw py::error_already_set();
     }
     py::buffer_info arrayInfo(view);
 
-    MlirContext context = contextWrapper.get();
+    MlirContext context = contextWrapper->get();
     // Switch on the types that can be bulk loaded between the Python and
     // MLIR-C APIs.
     if (arrayInfo.format == "f") {
       // f32
       assert(arrayInfo.itemsize == 4 && "mismatched array itemsize");
       return PyDenseElementsAttribute(
-          contextWrapper.getRef(),
+          contextWrapper->getRef(),
           bulkLoad(context, mlirDenseElementsAttrFloatGet,
                    mlirF32TypeGet(context), arrayInfo));
     } else if (arrayInfo.format == "d") {
       // f64
       assert(arrayInfo.itemsize == 8 && "mismatched array itemsize");
       return PyDenseElementsAttribute(
-          contextWrapper.getRef(),
+          contextWrapper->getRef(),
           bulkLoad(context, mlirDenseElementsAttrDoubleGet,
                    mlirF64TypeGet(context), arrayInfo));
     } else if (arrayInfo.format == "i") {
       // i32
       assert(arrayInfo.itemsize == 4 && "mismatched array itemsize");
       MlirType elementType = signless ? mlirIntegerTypeGet(context, 32)
                                       : mlirIntegerTypeSignedGet(context, 32);
-      return PyDenseElementsAttribute(contextWrapper.getRef(),
+      return PyDenseElementsAttribute(contextWrapper->getRef(),
                                       bulkLoad(context,
                                                mlirDenseElementsAttrInt32Get,
                                                elementType, arrayInfo));
     } else if (arrayInfo.format == "I") {
       // unsigned i32
       assert(arrayInfo.itemsize == 4 && "mismatched array itemsize");
       MlirType elementType = signless ? mlirIntegerTypeGet(context, 32)
                                       : mlirIntegerTypeUnsignedGet(context, 32);
-      return PyDenseElementsAttribute(contextWrapper.getRef(),
+      return PyDenseElementsAttribute(contextWrapper->getRef(),
                                       bulkLoad(context,
                                                mlirDenseElementsAttrUInt32Get,
                                                elementType, arrayInfo));
     } else if (arrayInfo.format == "l") {
       // i64
       assert(arrayInfo.itemsize == 8 && "mismatched array itemsize");
       MlirType elementType = signless ? mlirIntegerTypeGet(context, 64)
                                       : mlirIntegerTypeSignedGet(context, 64);
-      return PyDenseElementsAttribute(contextWrapper.getRef(),
+      return PyDenseElementsAttribute(contextWrapper->getRef(),
                                       bulkLoad(context,
                                                mlirDenseElementsAttrInt64Get,
                                                elementType, arrayInfo));
     } else if (arrayInfo.format == "L") {
       // unsigned i64
       assert(arrayInfo.itemsize == 8 && "mismatched array itemsize");
       MlirType elementType = signless ? mlirIntegerTypeGet(context, 64)
                                       : mlirIntegerTypeUnsignedGet(context, 64);
-      return PyDenseElementsAttribute(contextWrapper.getRef(),
+      return PyDenseElementsAttribute(contextWrapper->getRef(),
                                       bulkLoad(context,
                                                mlirDenseElementsAttrUInt64Get,
                                                elementType, arrayInfo));
     }
 
     // TODO: Fall back to string-based get.
     std::string message = "unimplemented array format conversion from format: ";
     message.append(arrayInfo.format);
static PyDenseElementsAttribute getSplat(PyType shapedType,
 
     MlirAttribute elements =
         mlirDenseElementsAttrSplatGet(shapedType.type, elementAttr.attr);
     return PyDenseElementsAttribute(contextWrapper->getRef(), elements);
   }
 
   static void bindDerived(ClassTy &c) {
     c.def_static("get", PyDenseElementsAttribute::getFromBuffer,
-                 py::arg("context"), py::arg("array"),
-                 py::arg("signless") = true, "Gets from a buffer or ndarray")
+                 py::arg("array"), py::arg("signless") = true,
+                 py::arg("context") = py::none(),
+                 "Gets from a buffer or ndarray")
         .def_static("get_splat", PyDenseElementsAttribute::getSplat,
                     py::arg("shaped_type"), py::arg("element_attr"),
                     "Gets a DenseElementsAttr where all values are the same")
         .def_property_readonly("is_splat",
                                [](PyDenseElementsAttribute &self) -> bool {
                                  return mlirDenseElementsAttrIsSplat(self.attr);
                                });
   }

 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAInteger;
   static constexpr const char *pyClassName = "IntegerType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get_signless",
-        [](PyMlirContext &context, unsigned width) {
-          MlirType t = mlirIntegerTypeGet(context.get(), width);
-          return PyIntegerType(context.getRef(), t);
+        [](unsigned width, DefaultingPyMlirContext context) {
+          MlirType t = mlirIntegerTypeGet(context->get(), width);
+          return PyIntegerType(context->getRef(), t);
         },
+        py::arg("width"), py::arg("context") = py::none(),
         "Create a signless integer type");
     c.def_static(
         "get_signed",
-        [](PyMlirContext &context, unsigned width) {
-          MlirType t = mlirIntegerTypeSignedGet(context.get(), width);
-          return PyIntegerType(context.getRef(), t);
+        [](unsigned width, DefaultingPyMlirContext context) {
+          MlirType t = mlirIntegerTypeSignedGet(context->get(), width);
+          return PyIntegerType(context->getRef(), t);
         },
+        py::arg("width"), py::arg("context") = py::none(),
         "Create a signed integer type");
     c.def_static(
         "get_unsigned",
-        [](PyMlirContext &context, unsigned width) {
-          MlirType t = mlirIntegerTypeUnsignedGet(context.get(), width);
-          return PyIntegerType(context.getRef(), t);
+        [](unsigned width, DefaultingPyMlirContext context) {
+          MlirType t = mlirIntegerTypeUnsignedGet(context->get(), width);
+          return PyIntegerType(context->getRef(), t);
         },
+        py::arg("width"), py::arg("context") = py::none(),
         "Create an unsigned integer type");
     c.def_property_readonly(
         "width",
         [](PyIntegerType &self) { return mlirIntegerTypeGetWidth(self.type); },
         "Returns the width of the integer type");
     c.def_property_readonly(
         "is_signless",
         [](PyIntegerType &self) -> bool {

 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAIndex;
   static constexpr const char *pyClassName = "IndexType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context) {
-          MlirType t = mlirIndexTypeGet(context.get());
-          return PyIndexType(context.getRef(), t);
+        [](DefaultingPyMlirContext context) {
+          MlirType t = mlirIndexTypeGet(context->get());
+          return PyIndexType(context->getRef(), t);
         },
-        "Create a index type.");
+        py::arg("context") = py::none(), "Create a index type.");
   }
 };
 
 /// Floating Point Type subclass - BF16Type.
 class PyBF16Type : public PyConcreteType<PyBF16Type> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsABF16;
   static constexpr const char *pyClassName = "BF16Type";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context) {
-          MlirType t = mlirBF16TypeGet(context.get());
-          return PyBF16Type(context.getRef(), t);
+        [](DefaultingPyMlirContext context) {
+          MlirType t = mlirBF16TypeGet(context->get());
+          return PyBF16Type(context->getRef(), t);
         },
-        "Create a bf16 type.");
+        py::arg("context") = py::none(), "Create a bf16 type.");
   }
 };
 
 /// Floating Point Type subclass - F16Type.
 class PyF16Type : public PyConcreteType<PyF16Type> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAF16;
   static constexpr const char *pyClassName = "F16Type";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context) {
-          MlirType t = mlirF16TypeGet(context.get());
-          return PyF16Type(context.getRef(), t);
+        [](DefaultingPyMlirContext context) {
+          MlirType t = mlirF16TypeGet(context->get());
+          return PyF16Type(context->getRef(), t);
         },
-        "Create a f16 type.");
+        py::arg("context") = py::none(), "Create a f16 type.");
   }
 };
 
 /// Floating Point Type subclass - F32Type.
 class PyF32Type : public PyConcreteType<PyF32Type> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAF32;
   static constexpr const char *pyClassName = "F32Type";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context) {
-          MlirType t = mlirF32TypeGet(context.get());
-          return PyF32Type(context.getRef(), t);
+        [](DefaultingPyMlirContext context) {
+          MlirType t = mlirF32TypeGet(context->get());
+          return PyF32Type(context->getRef(), t);
         },
-        "Create a f32 type.");
+        py::arg("context") = py::none(), "Create a f32 type.");
   }
 };
 
 /// Floating Point Type subclass - F64Type.
 class PyF64Type : public PyConcreteType<PyF64Type> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAF64;
   static constexpr const char *pyClassName = "F64Type";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context) {
-          MlirType t = mlirF64TypeGet(context.get());
-          return PyF64Type(context.getRef(), t);
+        [](DefaultingPyMlirContext context) {
+          MlirType t = mlirF64TypeGet(context->get());
+          return PyF64Type(context->getRef(), t);
         },
-        "Create a f64 type.");
+        py::arg("context") = py::none(), "Create a f64 type.");
   }
 };
 
 /// None Type subclass - NoneType.
 class PyNoneType : public PyConcreteType<PyNoneType> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsANone;
   static constexpr const char *pyClassName = "NoneType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context) {
-          MlirType t = mlirNoneTypeGet(context.get());
-          return PyNoneType(context.getRef(), t);
+        [](DefaultingPyMlirContext context) {
+          MlirType t = mlirNoneTypeGet(context->get());
+          return PyNoneType(context->getRef(), t);
         },
-        "Create a none type.");
+        py::arg("context") = py::none(), "Create a none type.");
   }
 };
 
 /// Complex Type subclass - ComplexType.
 class PyComplexType : public PyConcreteType<PyComplexType> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAComplex;
   static constexpr const char *pyClassName = "ComplexType";

 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAVector;
   static constexpr const char *pyClassName = "VectorType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        // TODO: Make the location optional and create a default location.
-        [](std::vector<int64_t> shape, PyType &elementType, PyLocation &loc) {
+        [](std::vector<int64_t> shape, PyType &elementType,
+           DefaultingPyLocation loc) {
           MlirType t = mlirVectorTypeGetChecked(shape.size(), shape.data(),
-                                                elementType.type, loc.loc);
+                                                elementType.type, loc->loc);
           // TODO: Rework error reporting once diagnostic engine is exposed
           // in C API.
           if (mlirTypeIsNull(t)) {
             throw SetPyError(
                 PyExc_ValueError,
                 llvm::Twine("invalid '") +
                     py::repr(py::cast(elementType)).cast<std::string>() +
                     "' and expected floating point or integer type.");
           }
           return PyVectorType(elementType.getContext(), t);
         },
+        py::arg("shape"), py::arg("elementType"), py::arg("loc") = py::none(),
         "Create a vector type");
   }
 };
 
 /// Ranked Tensor Type subclass - RankedTensorType.
 class PyRankedTensorType
     : public PyConcreteType<PyRankedTensorType, PyShapedType> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsARankedTensor;
   static constexpr const char *pyClassName = "RankedTensorType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        // TODO: Make the location optional and create a default location.
-        [](std::vector<int64_t> shape, PyType &elementType, PyLocation &loc) {
+        [](std::vector<int64_t> shape, PyType &elementType,
+           DefaultingPyLocation loc) {
           MlirType t = mlirRankedTensorTypeGetChecked(
-              shape.size(), shape.data(), elementType.type, loc.loc);
+              shape.size(), shape.data(), elementType.type, loc->loc);
           // TODO: Rework error reporting once diagnostic engine is exposed
           // in C API.
           if (mlirTypeIsNull(t)) {
             throw SetPyError(
                 PyExc_ValueError,
                 llvm::Twine("invalid '") +
                     py::repr(py::cast(elementType)).cast<std::string>() +
                     "' and expected floating point, integer, vector or "
                     "complex "
                     "type.");
           }
           return PyRankedTensorType(elementType.getContext(), t);
         },
+        py::arg("shape"), py::arg("element_type"), py::arg("loc") = py::none(),
         "Create a ranked tensor type");
   }
 };
 
 /// Unranked Tensor Type subclass - UnrankedTensorType.
 class PyUnrankedTensorType
     : public PyConcreteType<PyUnrankedTensorType, PyShapedType> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAUnrankedTensor;
   static constexpr const char *pyClassName = "UnrankedTensorType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        // TODO: Make the location optional and create a default location.
-        [](PyType &elementType, PyLocation &loc) {
+        [](PyType &elementType, DefaultingPyLocation loc) {
           MlirType t =
-              mlirUnrankedTensorTypeGetChecked(elementType.type, loc.loc);
+              mlirUnrankedTensorTypeGetChecked(elementType.type, loc->loc);
           // TODO: Rework error reporting once diagnostic engine is exposed
           // in C API.
           if (mlirTypeIsNull(t)) {
             throw SetPyError(
                 PyExc_ValueError,
                 llvm::Twine("invalid '") +
                     py::repr(py::cast(elementType)).cast<std::string>() +
                     "' and expected floating point, integer, vector or "
                     "complex "
                     "type.");
           }
           return PyUnrankedTensorType(elementType.getContext(), t);
         },
+        py::arg("element_type"), py::arg("loc") = py::none(),
         "Create a unranked tensor type");
   }
 };
 
 /// Ranked MemRef Type subclass - MemRefType.
 class PyMemRefType : public PyConcreteType<PyMemRefType, PyShapedType> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsARankedTensor;
   static constexpr const char *pyClassName = "MemRefType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     // TODO: Add mlirMemRefTypeGet and mlirMemRefTypeGetAffineMap binding
     // once the affine map binding is completed.
     c.def_static(
          "get_contiguous_memref",
          // TODO: Make the location optional and create a default location.
          [](PyType &elementType, std::vector<int64_t> shape,
-            unsigned memorySpace, PyLocation &loc) {
+            unsigned memorySpace, DefaultingPyLocation loc) {
            MlirType t = mlirMemRefTypeContiguousGetChecked(
                elementType.type, shape.size(), shape.data(), memorySpace,
-               loc.loc);
+               loc->loc);
            // TODO: Rework error reporting once diagnostic engine is exposed
            // in C API.
            if (mlirTypeIsNull(t)) {
              throw SetPyError(
                  PyExc_ValueError,
                  llvm::Twine("invalid '") +
                      py::repr(py::cast(elementType)).cast<std::string>() +
                      "' and expected floating point, integer, vector or "
                      "complex "
                      "type.");
            }
            return PyMemRefType(elementType.getContext(), t);
          },
-         "Create a memref type")
+         py::arg("element_type"), py::arg("shape"), py::arg("memory_space"),
+         py::arg("loc") = py::none(), "Create a memref type")
         .def_property_readonly(
             "num_affine_maps",
             [](PyMemRefType &self) -> intptr_t {
               return mlirMemRefTypeGetNumAffineMaps(self.type);
             },
             "Returns the number of affine layout maps in the given MemRef "
             "type.")
         .def_property_readonly(

 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAUnrankedMemRef;
   static constexpr const char *pyClassName = "UnrankedMemRefType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
          "get",
-         // TODO: Make the location optional and create a default location.
-         [](PyType &elementType, unsigned memorySpace, PyLocation &loc) {
+         [](PyType &elementType, unsigned memorySpace,
+            DefaultingPyLocation loc) {
            MlirType t = mlirUnrankedMemRefTypeGetChecked(elementType.type,
-                                                         memorySpace, loc.loc);
+                                                         memorySpace, loc->loc);
            // TODO: Rework error reporting once diagnostic engine is exposed
            // in C API.
            if (mlirTypeIsNull(t)) {
              throw SetPyError(
                  PyExc_ValueError,
                  llvm::Twine("invalid '") +
                      py::repr(py::cast(elementType)).cast<std::string>() +
                      "' and expected floating point, integer, vector or "
                      "complex "
                      "type.");
            }
            return PyUnrankedMemRefType(elementType.getContext(), t);
          },
-         "Create a unranked memref type")
+         py::arg("element_type"), py::arg("memory_space"),
+         py::arg("loc") = py::none(), "Create a unranked memref type")
         .def_property_readonly(
             "memory_space",
             [](PyUnrankedMemRefType &self) -> unsigned {
               return mlirUnrankedMemrefGetMemorySpace(self.type);
             },
             "Returns the memory space of the given Unranked MemRef type.");
   }
 };
 
 /// Tuple Type subclass - TupleType.
 class PyTupleType : public PyConcreteType<PyTupleType> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsATuple;
   static constexpr const char *pyClassName = "TupleType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get_tuple",
-        [](PyMlirContext &context, py::list elementList) {
+        [](py::list elementList, DefaultingPyMlirContext context) {
           intptr_t num = py::len(elementList);
           // Mapping py::list to SmallVector.
           SmallVector<MlirType, 4> elements;
           for (auto element : elementList)
             elements.push_back(element.cast<PyType>().type);
-          MlirType t = mlirTupleTypeGet(context.get(), num, elements.data());
-          return PyTupleType(context.getRef(), t);
+          MlirType t = mlirTupleTypeGet(context->get(), num, elements.data());
+          return PyTupleType(context->getRef(), t);
         },
+        py::arg("elements"), py::arg("context") = py::none(),
         "Create a tuple type");
     c.def(
         "get_type",
         [](PyTupleType &self, intptr_t pos) -> PyType {
           MlirType t = mlirTupleTypeGetType(self.type, pos);
           return PyType(self.getContext(), t);
         },
         "Returns the pos-th type in the tuple type.");

 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAFunction;
   static constexpr const char *pyClassName = "FunctionType";
   using PyConcreteType::PyConcreteType;
 
   static void bindDerived(ClassTy &c) {
     c.def_static(
         "get",
-        [](PyMlirContext &context, std::vector<PyType> inputs,
-           std::vector<PyType> results) {
+        [](std::vector<PyType> inputs, std::vector<PyType> results,
+           DefaultingPyMlirContext context) {
           SmallVector<MlirType, 4> inputsRaw(inputs.begin(), inputs.end());
           SmallVector<MlirType, 4> resultsRaw(results.begin(), results.end());
-          MlirType t = mlirFunctionTypeGet(context.get(), inputsRaw.size(),
+          MlirType t = mlirFunctionTypeGet(context->get(), inputsRaw.size(),
                                            inputsRaw.data(), resultsRaw.size(),
                                            resultsRaw.data());
-          return PyFunctionType(context.getRef(), t);
+          return PyFunctionType(context->getRef(), t);
         },
-        py::arg("context"), py::arg("inputs"), py::arg("results"),
+        py::arg("inputs"), py::arg("results"), py::arg("context") = py::none(),
         "Gets a FunctionType from a list of input and result types");
     c.def_property_readonly(
         "inputs",
         [](PyFunctionType &self) {
           MlirType t = self.type;
           auto contextRef = self.getContext();
           py::list types;
           for (intptr_t i = 0, e = mlirFunctionTypeGetNumInputs(self.type);
py::class_<PyMlirContext>(m, "Context")
              PyMlirContextRef ref = PyMlirContext::forContext(self.get());
              return ref.releaseObject();
            })
       .def("_get_live_operation_count", &PyMlirContext::getLiveOperationCount)
       .def("_get_live_module_count", &PyMlirContext::getLiveModuleCount)
       .def_property_readonly(MLIR_PYTHON_CAPI_PTR_ATTR,
                              &PyMlirContext::getCapsule)
       .def(MLIR_PYTHON_CAPI_FACTORY_ATTR, &PyMlirContext::createFromCapsule)
+      .def("__enter__", &PyMlirContext::contextEnter)
+      .def("__exit__", &PyMlirContext::contextExit)
+      .def_property_readonly_static(
+          "current",
+          [](py::object & /*class*/) {
+            auto *context = PyThreadContextEntry::getDefaultContext();
+            if (!context)
+              throw SetPyError(PyExc_ValueError, "No current Context");
+            return context;
+          },
+          "Gets the Context bound to the current thread or raises ValueError")
       .def_property_readonly(
           "dialects",
           [](PyMlirContext &self) { return PyDialects(self.getRef()); },
           "Gets a container for accessing dialects by name")
       .def_property_readonly(
           "d", [](PyMlirContext &self) { return PyDialects(self.getRef()); },
           "Alias for 'dialect'")
       .def(
           "get_dialect_descriptor",
           [=](PyMlirContext &self, std::string &name) {
             MlirDialect dialect = mlirContextGetOrLoadDialect(
                 self.get(), {name.data(), name.size()});
             if (mlirDialectIsNull(dialect)) {
               throw SetPyError(PyExc_ValueError,
                                llvm::Twine("Dialect '") + name + "' not found");
             }
             return PyDialectDescriptor(self.getRef(), dialect);
           },
-          "Gets or loads a dialect by name, returning its descriptor object")
+          "Gets or loads a dialect by name, returning its descriptor "
+          "object")
       .def_property(
           "allow_unregistered_dialects",
           [](PyMlirContext &self) -> bool {
             return mlirContextGetAllowUnregisteredDialects(self.get());
           },
           [](PyMlirContext &self, bool value) {
             mlirContextSetAllowUnregisteredDialects(self.get(), value);
-          })
-      .def("create_operation", &PyMlirContext::createOperation, py::arg("name"),
-           py::arg("location"), py::arg("operands") = py::none(),
-           py::arg("results") = py::none(), py::arg("attributes") = py::none(),
-           py::arg("successors") = py::none(), py::arg("regions") = 0,
-           kContextCreateOperationDocstring)
-      .def(
-          "parse_module",
-          [](PyMlirContext &self, const std::string moduleAsm) {
-            MlirModule module =
-                mlirModuleCreateParse(self.get(), moduleAsm.c_str());
-            // TODO: Rework error reporting once diagnostic engine is exposed
-            // in C API.
-            if (mlirModuleIsNull(module)) {
-              throw SetPyError(
-                  PyExc_ValueError,
-                  "Unable to parse module assembly (see diagnostics)");
-            }
-            return PyModule::forModule(module).releaseObject();
-          },
-          kContextParseDocstring)
-      .def(
-          "create_module",
-          [](PyMlirContext &self, PyLocation &loc) {
-            MlirModule module = mlirModuleCreateEmpty(loc.loc);
-            return PyModule::forModule(module).releaseObject();
-          },
-          py::arg("loc"), "Creates an empty module")
-      .def(
-          "parse_attr",
-          [](PyMlirContext &self, std::string attrSpec) {
-            MlirAttribute type =
-                mlirAttributeParseGet(self.get(), attrSpec.c_str());
-            // TODO: Rework error reporting once diagnostic engine is exposed
-            // in C API.
-            if (mlirAttributeIsNull(type)) {
-              throw SetPyError(PyExc_ValueError,
-                               llvm::Twine("Unable to parse attribute: '") +
-                                   attrSpec + "'");
-            }
-            return PyAttribute(self.getRef(), type);
-          },
-          py::keep_alive<0, 1>())
-      .def(
-          "parse_type",
-          [](PyMlirContext &self, std::string typeSpec) {
-            MlirType type = mlirTypeParseGet(self.get(), typeSpec.c_str());
-            // TODO: Rework error reporting once diagnostic engine is exposed
-            // in C API.
-            if (mlirTypeIsNull(type)) {
-              throw SetPyError(PyExc_ValueError,
-                               llvm::Twine("Unable to parse type: '") +
-                                   typeSpec + "'");
-            }
-            return PyType(self.getRef(), type);
-          },
-          kContextParseTypeDocstring)
-      .def(
-          "get_unknown_location",
-          [](PyMlirContext &self) {
-            return PyLocation(self.getRef(),
-                              mlirLocationUnknownGet(self.get()));
-          },
-          kContextGetUnknownLocationDocstring)
-      .def(
-          "get_file_location",
-          [](PyMlirContext &self, std::string filename, int line, int col) {
-            return PyLocation(self.getRef(),
-                              mlirLocationFileLineColGet(
-                                  self.get(), filename.c_str(), line, col));
-          },
-          kContextGetFileLocationDocstring, py::arg("filename"),
-          py::arg("line"), py::arg("col"));
+          });
 
   //----------------------------------------------------------------------------
   // Mapping of PyDialectDescriptor
   //----------------------------------------------------------------------------
   py::class_<PyDialectDescriptor>(m, "DialectDescriptor")
       .def_property_readonly("namespace",
                              [](PyDialectDescriptor &self) {
                                MlirStringRef ns =
py::class_<PyDialect>(m, "Dialect")
                clazz.attr("__module__") + py::str(".") +
                clazz.attr("__name__") + py::str(")>");
       });
 
   //----------------------------------------------------------------------------
   // Mapping of Location
   //----------------------------------------------------------------------------
   py::class_<PyLocation>(m, "Location")
+      .def("__enter__", &PyLocation::contextEnter)
+      .def("__exit__", &PyLocation::contextExit)
+      .def_property_readonly_static(
+          "current",
+          [](py::object & /*class*/) {
+            auto *loc = PyThreadContextEntry::getDefaultLocation();
+            if (!loc)
+              throw SetPyError(PyExc_ValueError, "No current Location");
+            return loc;
+          },
+          "Gets the Location bound to the current thread or raises ValueError")
+      .def_static(
+          "unknown",
+          [](DefaultingPyMlirContext context) {
+            return PyLocation(context->getRef(),
+                              mlirLocationUnknownGet(context->get()));
+          },
+          py::arg("context") = py::none(),
+          "Gets a Location representing an unknown location")
+      .def_static(
+          "file",
+          [](std::string filename, int line, int col,
+             DefaultingPyMlirContext context) {
+            return PyLocation(context->getRef(),
+                              mlirLocationFileLineColGet(
+                                  context->get(), filename.c_str(), line, col));
+          },
+          py::arg("filename"), py::arg("line"), py::arg("col"),
+          py::arg("context") = py::none(), kContextGetFileLocationDocstring)
       .def_property_readonly(
           "context",
           [](PyLocation &self) { return self.getContext().getObject(); },
           "Context that owns the Location")
       .def("__repr__", [](PyLocation &self) {
         PyPrintAccumulator printAccum;
         mlirLocationPrint(self.loc, printAccum.getCallback(),
                           printAccum.getUserData());
         return printAccum.join();
       });
 
   //----------------------------------------------------------------------------
   // Mapping of Module
   //----------------------------------------------------------------------------
   py::class_<PyModule>(m, "Module")
       .def_property_readonly(MLIR_PYTHON_CAPI_PTR_ATTR, &PyModule::getCapsule)
       .def(MLIR_PYTHON_CAPI_FACTORY_ATTR, &PyModule::createFromCapsule)
+      .def_static(
+          "parse",
+          [](const std::string moduleAsm, DefaultingPyMlirContext context) {
+            MlirModule module =
+                mlirModuleCreateParse(context->get(), moduleAsm.c_str());
+            // TODO: Rework error reporting once diagnostic engine is exposed
+            // in C API.
+            if (mlirModuleIsNull(module)) {
+              throw SetPyError(
+                  PyExc_ValueError,
+                  "Unable to parse module assembly (see diagnostics)");
+            }
+            return PyModule::forModule(module).releaseObject();
+          },
+          py::arg("asm"), py::arg("context") = py::none(),
+          kModuleParseDocstring)
+      .def_static(
+          "create",
+          [](DefaultingPyLocation loc) {
+            MlirModule module = mlirModuleCreateEmpty(loc->loc);
+            return PyModule::forModule(module).releaseObject();
+          },
+          py::arg("loc") = py::none(), "Creates an empty module")
       .def_property_readonly(
           "context",
           [](PyModule &self) { return self.getContext().getObject(); },
           "Context that created the Module")
       .def_property_readonly(
           "operation",
           [](PyModule &self) {
             return PyOperation::forOperation(self.getContext(),
py::class_<PyModule>(m, "Module")
             return printAccum.join();
           },
           kOperationStrDunderDocstring);
 
   //----------------------------------------------------------------------------
   // Mapping of Operation.
   //----------------------------------------------------------------------------
   py::class_<PyOperation>(m, "Operation")
+      .def_static("create", &PyOperation::create, py::arg("name"),
+                  py::arg("operands") = py::none(),
+                  py::arg("results") = py::none(),
+                  py::arg("attributes") = py::none(),
+                  py::arg("successors") = py::none(), py::arg("regions") = 0,
+                  py::arg("loc") = py::none(), py::arg("ip") = py::none(),
+                  kOperationCreateDocstring)
       .def_property_readonly(
           "context",
           [](PyOperation &self) { return self.getContext().getObject(); },
           "Context that owns the Operation")
       .def_property_readonly(
           "operands",
           [](PyOperation &self) { return PyOpOperandList(self.getRef()); })
       .def_property_readonly(
void mlir::python::populateIRSubmodule(py::module &m) {
   // Mapping of PyInsertionPoint.
   //----------------------------------------------------------------------------
 
   py::class_<PyInsertionPoint>(m, "InsertionPoint")
       .def(py::init<PyBlock &>(), py::arg("block"),
            "Inserts after the last operation but still inside the block.")
       .def("__enter__", &PyInsertionPoint::contextEnter)
       .def("__exit__", &PyInsertionPoint::contextExit)
+      .def_property_readonly_static(
+          "current",
+          [](py::object & /*class*/) {
+            auto *ip = PyThreadContextEntry::getDefaultInsertionPoint();
+            if (!ip)
+              throw SetPyError(PyExc_ValueError, "No current InsertionPoint");
+            return ip;
+          },
+          "Gets the InsertionPoint bound to the current thread or raises "
+          "ValueError")
       .def(py::init<PyOperation &>(), py::arg("beforeOperation"),
            "Inserts before a referenced operation.")
       .def_static("at_block_begin", &PyInsertionPoint::atBlockBegin,
                   py::arg("block"), "Inserts at the beginning of the block.")
       .def_static("at_block_terminator", &PyInsertionPoint::atBlockTerminator,
                   py::arg("block"), "Inserts before the block terminator.")
       .def("insert", &PyInsertionPoint::insert, py::arg("operation"),
            "Inserts an operation.");
 
   //----------------------------------------------------------------------------
   // Mapping of PyAttribute.
   //----------------------------------------------------------------------------
   py::class_<PyAttribute>(m, "Attribute")
+      .def_static(
+          "parse",
+          [](std::string attrSpec, DefaultingPyMlirContext context) {
+            MlirAttribute type =
+                mlirAttributeParseGet(context->get(), attrSpec.c_str());
+            // TODO: Rework error reporting once diagnostic engine is exposed
+            // in C API.
+            if (mlirAttributeIsNull(type)) {
+              throw SetPyError(PyExc_ValueError,
+                               llvm::Twine("Unable to parse attribute: '") +
+                                   attrSpec + "'");
+            }
+            return PyAttribute(context->getRef(), type);
+          },
+          py::arg("asm"), py::arg("context") = py::none(),
+          "Parses an attribute from an assembly form")
       .def_property_readonly(
           "context",
           [](PyAttribute &self) { return self.getContext().getObject(); },
           "Context that owns the Attribute")
       .def_property_readonly("type",
                              [](PyAttribute &self) {
                                return PyType(self.getContext()->getRef(),
                                              mlirAttributeGetType(self.attr));
void mlir::python::populateIRSubmodule(py::module &m) {
   PyBoolAttribute::bind(m);
   PyStringAttribute::bind(m);
   PyDenseElementsAttribute::bind(m);
 
   //----------------------------------------------------------------------------
   // Mapping of PyType.
   //----------------------------------------------------------------------------
   py::class_<PyType>(m, "Type")
+      .def_static(
+          "parse",
+          [](std::string typeSpec, DefaultingPyMlirContext context) {
+            MlirType type = mlirTypeParseGet(context->get(), typeSpec.c_str());
+            // TODO: Rework error reporting once diagnostic engine is exposed
+            // in C API.
+            if (mlirTypeIsNull(type)) {
+              throw SetPyError(PyExc_ValueError,
+                               llvm::Twine("Unable to parse type: '") +
+                                   typeSpec + "'");
+            }
+            return PyType(context->getRef(), type);
+          },
+          py::arg("asm"), py::arg("context") = py::none(),
+          kContextParseTypeDocstring)
       .def_property_readonly(
           "context", [](PyType &self) { return self.getContext().getObject(); },
           "Context that owns the Type")
       .def("__eq__",
            [](PyType &self, py::object &other) {
              try {
                PyType otherType = other.cast<PyType>();
                return self == otherType;

mlir/lib/Bindings/Python/PybindUtils.h

 //===- PybindUtils.h - Utilities for interop with pybind11 ------*- 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
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef MLIR_BINDINGS_PYTHON_PYBINDUTILS_H
 #define MLIR_BINDINGS_PYTHON_PYBINDUTILS_H
 
 #include <pybind11/pybind11.h>
 #include <pybind11/stl.h>
 
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/Twine.h"
 
-namespace pybind11 {
-namespace detail {
-template <typename T>
-struct type_caster<llvm::Optional<T>> : optional_caster<llvm::Optional<T>> {};
-} // namespace detail
-} // namespace pybind11
-
 namespace mlir {
 namespace python {
 
 // Sets a python error, ready to be thrown to return control back to the
 // python runtime.
 // Correct usage:
 //   throw SetPyError(PyExc_ValueError, "Foobar'd");
 pybind11::error_already_set SetPyError(PyObject *excClass,
                                        const llvm::Twine &message);
 
+/// CRTP template for special wrapper types that are allowed to be passed in as
+/// 'None' function arguments and can be resolved by some global mechanic if
+/// so. Such types will raise an error if this global resolution fails, and
+/// it is actually illegal for them to ever be unresolved. From a user
+/// perspective, they behave like a smart ptr to the underlying type (i.e.
+/// 'get' method and operator-> overloaded).
+///
+/// Derived types must provide a method, which is called when an environmental
+/// resolution is required. It must raise an exception if resolution fails:
+///   static ReferrentTy &resolve()
+///
+/// They must also provide a parameter description that will be used in
+/// error messages about mismatched types:
+///   static constexpr const char kTypeDescription[] = "<Description>";
+
+template <typename DerivedTy, typename T>
+class Defaulting {
+public:
+  using ReferrentTy = T;
+  /// Type casters require the type to be default constructible, but using
+  /// such an instance is illegal.
+  Defaulting() = default;
+  Defaulting(ReferrentTy &referrent) : referrent(&referrent) {}
+
+  ReferrentTy *get() { return referrent; }
+  ReferrentTy *operator->() { return referrent; }
+
+private:
+  ReferrentTy *referrent = nullptr;
+};
+
 } // namespace python
 } // namespace mlir
 
+namespace pybind11 {
+namespace detail {
+
+template <typename DefaultingTy>
+struct MlirDefaultingCaster {
+  PYBIND11_TYPE_CASTER(DefaultingTy, _(DefaultingTy::kTypeDescription));
+
+  bool load(pybind11::handle src, bool) {
+    if (src.is_none()) {
+      // Note that we do want an exception to propagate from here as it will be
+      // the most informative.
+      value = DefaultingTy{DefaultingTy::resolve()};
+      return true;
+    }
+
+    // Unlike many casters that chain, these casters are expected to always
+    // succeed, so instead of doing an isinstance check followed by a cast,
+    // just cast in one step and handle the exception. Returning false (vs
+    // letting the exception propagate) causes higher level signature parsing
+    // code to produce nice error messages (other than "Cannot cast...").
+    try {
+      value = DefaultingTy{
+          pybind11::cast<typename DefaultingTy::ReferrentTy &>(src)};
+      return true;
+    } catch (std::exception &e) {
+      return false;
+    }
+  }
+
+  static handle cast(DefaultingTy src, return_value_policy policy,
+                     handle parent) {
+    return pybind11::cast(src, policy);
+  }
+};
+
+template <typename T>
+struct type_caster<llvm::Optional<T>> : optional_caster<llvm::Optional<T>> {};
+} // namespace detail
+} // namespace pybind11
+
 #endif // MLIR_BINDINGS_PYTHON_PYBINDUTILS_H

mlir/lib/Bindings/Python/mlir/dialects/std.py

 #  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
 
 # TODO: This file should be auto-generated.
 
 from . import _cext
+_ir = _cext.ir
 
 @_cext.register_dialect
-class _Dialect(_cext.ir.Dialect):
+class _Dialect(_ir.Dialect):
   # Special case: 'std' namespace aliases to the empty namespace.
   DIALECT_NAMESPACE = "std"
   pass
 
 @_cext.register_operation(_Dialect)
-class AddFOp(_cext.ir.OpView):
+class AddFOp(_ir.OpView):
   OPERATION_NAME = "std.addf"
 
-  def __init__(self, loc, lhs, rhs):
-    super().__init__(loc.context.create_operation(
-      "std.addf", loc, operands=[lhs, rhs], results=[lhs.type]))
+  def __init__(self, lhs, rhs, loc=None, ip=None):
+    super().__init__(_ir.Operation.create(
+      "std.addf", operands=[lhs, rhs], results=[lhs.type],
+      loc=loc, ip=ip))
 
   @property
   def lhs(self):
     return self.operation.operands[0]
 
   @property
   def rhs(self):
     return self.operation.operands[1]
 
   @property
   def result(self):
     return self.operation.results[0]

mlir/test/Bindings/Python/context_managers.py

+# RUN: %PYTHON %s | FileCheck %s
+
+import gc
+from mlir.ir import *
+
+def run(f):
+  print("\nTEST:", f.__name__)
+  f()
+  gc.collect()
+  assert Context._get_live_count() == 0
+
+
+# CHECK-LABEL: TEST: testContextEnterExit
+def testContextEnterExit():
+  with Context() as ctx:
+    assert Context.current is ctx
+  try:
+    _ = Context.current
+  except ValueError as e:
+    # CHECK: No current Context
+    print(e)
+  else: assert False, "Expected exception"
+
+run(testContextEnterExit)
+
+
+# CHECK-LABEL: TEST: testLocationEnterExit
+def testLocationEnterExit():
+  ctx1 = Context()
+  with Location.unknown(ctx1) as loc1:
+    assert Context.current is ctx1
+    assert Location.current is loc1
+
+    # Re-asserting the same context should not change the location.
+    with ctx1:
+      assert Context.current is ctx1
+      assert Location.current is loc1
+      # Asserting a different context should clear it.
+      with Context() as ctx2:
+        assert Context.current is ctx2
+        try:
+          _ = Location.current
+        except ValueError: pass
+        else: assert False, "Expected exception"
+
+      # And should restore.
+      assert Context.current is ctx1
+      assert Location.current is loc1
+
+  # All should clear.
+  try:
+    _ = Location.current
+  except ValueError as e:
+    # CHECK: No current Location
+    print(e)
+  else: assert False, "Expected exception"
+
+run(testLocationEnterExit)
+
+
+# CHECK-LABEL: TEST: testInsertionPointEnterExit
+def testInsertionPointEnterExit():
+  ctx1 = Context()
+  m = Module.create(Location.unknown(ctx1))
+  ip = InsertionPoint.at_block_terminator(m.body)
+
+  with ip:
+    assert InsertionPoint.current is ip
+    # Asserting a location from the same context should preserve.
+    with Location.unknown(ctx1) as loc1:
+      assert InsertionPoint.current is ip
+      assert Location.current is loc1
+    # Location should clear.
+    try:
+      _ = Location.current
+    except ValueError: pass
+    else: assert False, "Expected exception"
+
+    # Asserting the same Context should preserve.
+    with ctx1:
+      assert InsertionPoint.current is ip
+
+    # Asserting a different context should clear it.
+    with Context() as ctx2:
+      assert Context.current is ctx2
+      try:
+        _ = InsertionPoint.current
+      except ValueError: pass
+      else: assert False, "Expected exception"
+
+  # All should clear.
+  try:
+    _ = InsertionPoint.current
+  except ValueError as e:
+    # CHECK: No current InsertionPoint
+    print(e)
+  else: assert False, "Expected exception"
+
+run(testInsertionPointEnterExit)

mlir/test/Bindings/Python/dialects.py

 # RUN: %PYTHON %s | FileCheck %s
 
 import gc
-import mlir
+from mlir.ir import *
 
 def run(f):
   print("\nTEST:", f.__name__)
   f()
   gc.collect()
-  assert mlir.ir.Context._get_live_count() == 0
+  assert Context._get_live_count() == 0
 
 
 # CHECK-LABEL: TEST: testDialectDescriptor
 def testDialectDescriptor():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   d = ctx.get_dialect_descriptor("std")
   # CHECK: <DialectDescriptor std>
   print(d)
   # CHECK: std
   print(d.namespace)
   try:
     _ = ctx.get_dialect_descriptor("not_existing")
   except ValueError:
     pass
   else:
     assert False, "Expected exception"
 
 run(testDialectDescriptor)
 
 
 # CHECK-LABEL: TEST: testUserDialectClass
 def testUserDialectClass():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   # Access using attribute.
   d = ctx.dialects.std
   # Note that the standard dialect namespace prints as ''. Others will print
   # as "<Dialect %namespace (..."
   # CHECK: <Dialect (class mlir.dialects.std._Dialect)>
   print(d)
   try:
     _ = ctx.dialects.not_existing

 run(testUserDialectClass)
 
 
 # CHECK-LABEL: TEST: testCustomOpView
 # This test uses the standard dialect AddFOp as an example of a user op.
 # TODO: Op creation and access is still quite verbose: simplify this test as
 # additional capabilities come online.
 def testCustomOpView():
-  ctx = mlir.ir.Context()
-  ctx.allow_unregistered_dialects = True
-  f32 = mlir.ir.F32Type.get(ctx)
-  loc = ctx.get_unknown_location()
-  m = ctx.create_module(loc)
-
   def createInput():
-    op = ctx.create_operation("pytest_dummy.intinput", loc, results=[f32])
+    op = Operation.create("pytest_dummy.intinput", results=[f32])
     # TODO: Auto result cast from operation
     return op.results[0]
 
-  with mlir.ir.InsertionPoint.at_block_terminator(m.body):
+  with Context() as ctx, Location.unknown():
+    ctx.allow_unregistered_dialects = True
+    m = Module.create()
+
+    with InsertionPoint.at_block_terminator(m.body):
+      f32 = F32Type.get()
       # Create via dialects context collection.
       input1 = createInput()
       input2 = createInput()
-    op1 = ctx.dialects.std.AddFOp(loc, input1, input2)
+      op1 = ctx.dialects.std.AddFOp(input1, input2)
 
       # Create via an import
       from mlir.dialects.std import AddFOp
-    AddFOp(loc, input1, op1.result)
+      AddFOp(input1, op1.result)
 
   # CHECK: %[[INPUT0:.*]] = "pytest_dummy.intinput"
   # CHECK: %[[INPUT1:.*]] = "pytest_dummy.intinput"
   # CHECK: %[[R0:.*]] = addf %[[INPUT0]], %[[INPUT1]] : f32
   # CHECK: %[[R1:.*]] = addf %[[INPUT0]], %[[R0]] : f32
   m.operation.print()
 
 run(testCustomOpView)

mlir/test/Bindings/Python/insertion_point.py

def run(f):
   gc.collect()
   assert Context._get_live_count() == 0
 
 
 # CHECK-LABEL: TEST: test_insert_at_block_end
 def test_insert_at_block_end():
   ctx = Context()
   ctx.allow_unregistered_dialects = True
-  loc = ctx.get_unknown_location()
-  module = ctx.parse_module(r"""
+  with Location.unknown(ctx):
+    module = Module.parse(r"""
       func @foo() -> () {
         "custom.op1"() : () -> ()
       }
     """)
     entry_block = module.body.operations[0].regions[0].blocks[0]
     ip = InsertionPoint(entry_block)
-  ip.insert(ctx.create_operation("custom.op2", loc))
+    ip.insert(Operation.create("custom.op2"))
     # CHECK: "custom.op1"
     # CHECK: "custom.op2"
     module.operation.print()
 
 run(test_insert_at_block_end)
 
 
 # CHECK-LABEL: TEST: test_insert_before_operation
 def test_insert_before_operation():
   ctx = Context()
   ctx.allow_unregistered_dialects = True
-  loc = ctx.get_unknown_location()
-  module = ctx.parse_module(r"""
+  with Location.unknown(ctx):
+    module = Module.parse(r"""
       func @foo() -> () {
         "custom.op1"() : () -> ()
         "custom.op2"() : () -> ()
       }
     """)
     entry_block = module.body.operations[0].regions[0].blocks[0]
     ip = InsertionPoint(entry_block.operations[1])
-  ip.insert(ctx.create_operation("custom.op3", loc))
+    ip.insert(Operation.create("custom.op3"))
     # CHECK: "custom.op1"
     # CHECK: "custom.op3"
     # CHECK: "custom.op2"
     module.operation.print()
 
 run(test_insert_before_operation)
 
 
 # CHECK-LABEL: TEST: test_insert_at_block_begin
 def test_insert_at_block_begin():
   ctx = Context()
   ctx.allow_unregistered_dialects = True
-  loc = ctx.get_unknown_location()
-  module = ctx.parse_module(r"""
+  with Location.unknown(ctx):
+    module = Module.parse(r"""
       func @foo() -> () {
         "custom.op2"() : () -> ()
       }
     """)
     entry_block = module.body.operations[0].regions[0].blocks[0]
     ip = InsertionPoint.at_block_begin(entry_block)
-  ip.insert(ctx.create_operation("custom.op1", loc))
+    ip.insert(Operation.create("custom.op1"))
     # CHECK: "custom.op1"
     # CHECK: "custom.op2"
     module.operation.print()
 
 run(test_insert_at_block_begin)
 
 
 # CHECK-LABEL: TEST: test_insert_at_block_begin_empty
 def test_insert_at_block_begin_empty():
   # TODO: Write this test case when we can create such a situation.
   pass
 
 run(test_insert_at_block_begin_empty)
 
 
 # CHECK-LABEL: TEST: test_insert_at_terminator
 def test_insert_at_terminator():
   ctx = Context()
   ctx.allow_unregistered_dialects = True
-  loc = ctx.get_unknown_location()
-  module = ctx.parse_module(r"""
+  with Location.unknown(ctx):
+    module = Module.parse(r"""
       func @foo() -> () {
         "custom.op1"() : () -> ()
         return
       }
     """)
     entry_block = module.body.operations[0].regions[0].blocks[0]
     ip = InsertionPoint.at_block_terminator(entry_block)
-  ip.insert(ctx.create_operation("custom.op2", loc))
+    ip.insert(Operation.create("custom.op2"))
     # CHECK: "custom.op1"
     # CHECK: "custom.op2"
     module.operation.print()
 
 run(test_insert_at_terminator)
 
 
 # CHECK-LABEL: TEST: test_insert_at_block_terminator_missing
 def test_insert_at_block_terminator_missing():
   ctx = Context()
   ctx.allow_unregistered_dialects = True
-  loc = ctx.get_unknown_location()
-  module = ctx.parse_module(r"""
+  with ctx:
+    module = Module.parse(r"""
       func @foo() -> () {
         "custom.op1"() : () -> ()
       }
     """)
     entry_block = module.body.operations[0].regions[0].blocks[0]
     try:
       ip = InsertionPoint.at_block_terminator(entry_block)
     except ValueError as e:
       # CHECK: Block has no terminator
       print(e)
     else:
       assert False, "Expected exception"
 
 run(test_insert_at_block_terminator_missing)
 
 
 # CHECK-LABEL: TEST: test_insertion_point_context
 def test_insertion_point_context():
   ctx = Context()
   ctx.allow_unregistered_dialects = True
-  loc = ctx.get_unknown_location()
-  module = ctx.parse_module(r"""
+  with Location.unknown(ctx):
+    module = Module.parse(r"""
       func @foo() -> () {
         "custom.op1"() : () -> ()
       }
     """)
     entry_block = module.body.operations[0].regions[0].blocks[0]
     with InsertionPoint(entry_block):
-    ctx.create_operation("custom.op2", loc)
+      Operation.create("custom.op2")
       with InsertionPoint.at_block_begin(entry_block):
-      ctx.create_operation("custom.opa", loc)
-      ctx.create_operation("custom.opb", loc)
-    ctx.create_operation("custom.op3", loc)
+        Operation.create("custom.opa")
+        Operation.create("custom.opb")
+      Operation.create("custom.op3")
     # CHECK: "custom.opa"
     # CHECK: "custom.opb"
     # CHECK: "custom.op1"
     # CHECK: "custom.op2"
     # CHECK: "custom.op3"
     module.operation.print()
 
 run(test_insertion_point_context)

mlir/test/Bindings/Python/ir_array_attributes.py

 # RUN: %PYTHON %s | FileCheck %s
 # Note that this is separate from ir_attributes.py since it depends on numpy,
 # and we may want to disable if not available.
 
 import gc
-import mlir
+from mlir.ir import *
 import numpy as np
 
 def run(f):
   print("\nTEST:", f.__name__)
   f()
   gc.collect()
-  assert mlir.ir.Context._get_live_count() == 0
+  assert Context._get_live_count() == 0
 
 ################################################################################
 # Tests of the array/buffer .get() factory method on unsupported dtype.
 ################################################################################
 
 def testGetDenseElementsUnsupported():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([["hello", "goodbye"]])
     try:
-    attr = mlir.ir.DenseElementsAttr.get(ctx, array)
+      attr = DenseElementsAttr.get(array)
     except ValueError as e:
       # CHECK: unimplemented array format conversion from format:
       print(e)
 
 run(testGetDenseElementsUnsupported)
 
 ################################################################################
 # Splats.
 ################################################################################
 
 # CHECK-LABEL: TEST: testGetDenseElementsSplatInt
 def testGetDenseElementsSplatInt():
-  ctx = mlir.ir.Context()
-  loc = ctx.get_unknown_location()
-  t = mlir.ir.IntegerType.get_signless(ctx, 32)
-  element = mlir.ir.IntegerAttr.get(t, 555)
-  shaped_type = mlir.ir.RankedTensorType.get((2, 3, 4), t, loc)
-  attr = mlir.ir.DenseElementsAttr.get_splat(shaped_type, element)
+  with Context(), Location.unknown():
+    t = IntegerType.get_signless(32)
+    element = IntegerAttr.get(t, 555)
+    shaped_type = RankedTensorType.get((2, 3, 4), t)
+    attr = DenseElementsAttr.get_splat(shaped_type, element)
     # CHECK: dense<555> : tensor<2x3x4xi32>
     print(attr)
     # CHECK: is_splat: True
     print("is_splat:", attr.is_splat)
 
 run(testGetDenseElementsSplatInt)
 
 
 # CHECK-LABEL: TEST: testGetDenseElementsSplatFloat
 def testGetDenseElementsSplatFloat():
-  ctx = mlir.ir.Context()
-  loc = ctx.get_unknown_location()
-  t = mlir.ir.F32Type.get(ctx)
-  element = mlir.ir.FloatAttr.get(t, 1.2, loc)
-  shaped_type = mlir.ir.RankedTensorType.get((2, 3, 4), t, loc)
-  attr = mlir.ir.DenseElementsAttr.get_splat(shaped_type, element)
+  with Context(), Location.unknown():
+    t = F32Type.get()
+    element = FloatAttr.get(t, 1.2)
+    shaped_type = RankedTensorType.get((2, 3, 4), t)
+    attr = DenseElementsAttr.get_splat(shaped_type, element)
     # CHECK: dense<1.200000e+00> : tensor<2x3x4xf32>
     print(attr)
 
 run(testGetDenseElementsSplatFloat)
 
 
 # CHECK-LABEL: TEST: testGetDenseElementsSplatErrors
 def testGetDenseElementsSplatErrors():
-  ctx = mlir.ir.Context()
-  loc = ctx.get_unknown_location()
-  t = mlir.ir.F32Type.get(ctx)
-  other_t = mlir.ir.F64Type.get(ctx)
-  element = mlir.ir.FloatAttr.get(t, 1.2, loc)
-  other_element = mlir.ir.FloatAttr.get(other_t, 1.2, loc)
-  shaped_type = mlir.ir.RankedTensorType.get((2, 3, 4), t, loc)
-  dynamic_shaped_type = mlir.ir.UnrankedTensorType.get(t, loc)
+  with Context(), Location.unknown():
+    t = F32Type.get()
+    other_t = F64Type.get()
+    element = FloatAttr.get(t, 1.2)
+    other_element = FloatAttr.get(other_t, 1.2)
+    shaped_type = RankedTensorType.get((2, 3, 4), t)
+    dynamic_shaped_type = UnrankedTensorType.get(t)
     non_shaped_type = t
 
     try:
-    attr = mlir.ir.DenseElementsAttr.get_splat(non_shaped_type, element)
+      attr = DenseElementsAttr.get_splat(non_shaped_type, element)
     except ValueError as e:
       # CHECK: Expected a static ShapedType for the shaped_type parameter: Type(f32)
       print(e)
 
     try:
-    attr = mlir.ir.DenseElementsAttr.get_splat(dynamic_shaped_type, element)
+      attr = DenseElementsAttr.get_splat(dynamic_shaped_type, element)
     except ValueError as e:
       # CHECK: Expected a static ShapedType for the shaped_type parameter: Type(tensor<*xf32>)
       print(e)
 
     try:
-    attr = mlir.ir.DenseElementsAttr.get_splat(shaped_type, other_element)
+      attr = DenseElementsAttr.get_splat(shaped_type, other_element)
     except ValueError as e:
       # CHECK: Shaped element type and attribute type must be equal: shaped=Type(tensor<2x3x4xf32>), element=Attribute(1.200000e+00 : f64)
       print(e)
 
 run(testGetDenseElementsSplatErrors)
 
 
 ################################################################################
 # Tests of the array/buffer .get() factory method, in all of its permutations.
 ################################################################################
 
 ### float and double arrays.
 
 # CHECK-LABEL: TEST: testGetDenseElementsF32
 def testGetDenseElementsF32():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1.1, 2.2, 3.3], [4.4, 5.5, 6.6]], dtype=np.float32)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array)
+    attr = DenseElementsAttr.get(array)
     # CHECK: dense<{{\[}}[1.100000e+00, 2.200000e+00, 3.300000e+00], [4.400000e+00, 5.500000e+00, 6.600000e+00]]> : tensor<2x3xf32>
     print(attr)
     # CHECK: is_splat: False
     print("is_splat:", attr.is_splat)
 
 run(testGetDenseElementsF32)
 
 
 # CHECK-LABEL: TEST: testGetDenseElementsF64
 def testGetDenseElementsF64():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1.1, 2.2, 3.3], [4.4, 5.5, 6.6]], dtype=np.float64)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array)
+    attr = DenseElementsAttr.get(array)
     # CHECK: dense<{{\[}}[1.100000e+00, 2.200000e+00, 3.300000e+00], [4.400000e+00, 5.500000e+00, 6.600000e+00]]> : tensor<2x3xf64>
     print(attr)
 
 run(testGetDenseElementsF64)
 
 
 ### 32 bit integer arrays
 # CHECK-LABEL: TEST: testGetDenseElementsI32Signless
 def testGetDenseElementsI32Signless():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1, 2, 3], [4, 5, 6]], dtype=np.int32)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array)
+    attr = DenseElementsAttr.get(array)
     # CHECK: dense<{{\[}}[1, 2, 3], [4, 5, 6]]> : tensor<2x3xi32>
     print(attr)
 
 run(testGetDenseElementsI32Signless)
 
 
 # CHECK-LABEL: TEST: testGetDenseElementsUI32Signless
 def testGetDenseElementsUI32Signless():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1, 2, 3], [4, 5, 6]], dtype=np.uint32)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array)
+    attr = DenseElementsAttr.get(array)
     # CHECK: dense<{{\[}}[1, 2, 3], [4, 5, 6]]> : tensor<2x3xi32>
     print(attr)
 
 run(testGetDenseElementsUI32Signless)
 
 # CHECK-LABEL: TEST: testGetDenseElementsI32
 def testGetDenseElementsI32():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1, 2, 3], [4, 5, 6]], dtype=np.int32)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array, signless=False)
+    attr = DenseElementsAttr.get(array, signless=False)
     # CHECK: dense<{{\[}}[1, 2, 3], [4, 5, 6]]> : tensor<2x3xsi32>
     print(attr)
 
 run(testGetDenseElementsI32)
 
 
 # CHECK-LABEL: TEST: testGetDenseElementsUI32
 def testGetDenseElementsUI32():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1, 2, 3], [4, 5, 6]], dtype=np.uint32)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array, signless=False)
+    attr = DenseElementsAttr.get(array, signless=False)
     # CHECK: dense<{{\[}}[1, 2, 3], [4, 5, 6]]> : tensor<2x3xui32>
     print(attr)
 
 run(testGetDenseElementsUI32)
 
 
 ## 64bit integer arrays
 # CHECK-LABEL: TEST: testGetDenseElementsI64Signless
 def testGetDenseElementsI64Signless():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1, 2, 3], [4, 5, 6]], dtype=np.int64)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array)
+    attr = DenseElementsAttr.get(array)
     # CHECK: dense<{{\[}}[1, 2, 3], [4, 5, 6]]> : tensor<2x3xi64>
     print(attr)
 
 run(testGetDenseElementsI64Signless)
 
 
 # CHECK-LABEL: TEST: testGetDenseElementsUI64Signless
 def testGetDenseElementsUI64Signless():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1, 2, 3], [4, 5, 6]], dtype=np.uint64)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array)
+    attr = DenseElementsAttr.get(array)
     # CHECK: dense<{{\[}}[1, 2, 3], [4, 5, 6]]> : tensor<2x3xi64>
     print(attr)
 
 run(testGetDenseElementsUI64Signless)
 
 # CHECK-LABEL: TEST: testGetDenseElementsI64
 def testGetDenseElementsI64():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1, 2, 3], [4, 5, 6]], dtype=np.int64)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array, signless=False)
+    attr = DenseElementsAttr.get(array, signless=False)
     # CHECK: dense<{{\[}}[1, 2, 3], [4, 5, 6]]> : tensor<2x3xsi64>
     print(attr)
 
 run(testGetDenseElementsI64)
 
 
 # CHECK-LABEL: TEST: testGetDenseElementsUI64
 def testGetDenseElementsUI64():
-  ctx = mlir.ir.Context()
+  with Context():
     array = np.array([[1, 2, 3], [4, 5, 6]], dtype=np.uint64)
-  attr = mlir.ir.DenseElementsAttr.get(ctx, array, signless=False)
+    attr = DenseElementsAttr.get(array, signless=False)
     # CHECK: dense<{{\[}}[1, 2, 3], [4, 5, 6]]> : tensor<2x3xui64>
     print(attr)
 
 run(testGetDenseElementsUI64)
 

mlir/test/Bindings/Python/ir_attributes.py

 # RUN: %PYTHON %s | FileCheck %s
 
 import gc
-import mlir
+from mlir.ir import *
 
 def run(f):
   print("\nTEST:", f.__name__)
   f()
   gc.collect()
-  assert mlir.ir.Context._get_live_count() == 0
+  assert Context._get_live_count() == 0
 
 
 # CHECK-LABEL: TEST: testParsePrint
 def testParsePrint():
-  ctx = mlir.ir.Context()
-  t = ctx.parse_attr('"hello"')
+  with Context() as ctx:
+    t = Attribute.parse('"hello"')
   assert t.context is ctx
   ctx = None
   gc.collect()
   # CHECK: "hello"
   print(str(t))
   # CHECK: Attribute("hello")
   print(repr(t))
 
 run(testParsePrint)
 
 
 # CHECK-LABEL: TEST: testParseError
 # TODO: Hook the diagnostic manager to capture a more meaningful error
 # message.
 def testParseError():
-  ctx = mlir.ir.Context()
+  with Context():
     try:
-    t = ctx.parse_attr("BAD_ATTR_DOES_NOT_EXIST")
+      t = Attribute.parse("BAD_ATTR_DOES_NOT_EXIST")
     except ValueError as e:
       # CHECK: Unable to parse attribute: 'BAD_ATTR_DOES_NOT_EXIST'
       print("testParseError:", e)
     else:
       print("Exception not produced")
 
 run(testParseError)
 
 
 # CHECK-LABEL: TEST: testAttrEq
 def testAttrEq():
-  ctx = mlir.ir.Context()
-  a1 = ctx.parse_attr('"attr1"')
-  a2 = ctx.parse_attr('"attr2"')
-  a3 = ctx.parse_attr('"attr1"')
+  with Context():
+    a1 = Attribute.parse('"attr1"')
+    a2 = Attribute.parse('"attr2"')
+    a3 = Attribute.parse('"attr1"')
     # CHECK: a1 == a1: True
     print("a1 == a1:", a1 == a1)
     # CHECK: a1 == a2: False
     print("a1 == a2:", a1 == a2)
     # CHECK: a1 == a3: True
     print("a1 == a3:", a1 == a3)
     # CHECK: a1 == None: False
     print("a1 == None:", a1 == None)
 
 run(testAttrEq)
 
 
 # CHECK-LABEL: TEST: testAttrEqDoesNotRaise
 def testAttrEqDoesNotRaise():
-  ctx = mlir.ir.Context()
-  a1 = ctx.parse_attr('"attr1"')
+  with Context():
+    a1 = Attribute.parse('"attr1"')
     not_an_attr = "foo"
     # CHECK: False
     print(a1 == not_an_attr)
     # CHECK: False
     print(a1 == None)
     # CHECK: True
     print(a1 != None)
 
 run(testAttrEqDoesNotRaise)
 
 
 # CHECK-LABEL: TEST: testStandardAttrCasts
 def testStandardAttrCasts():
-  ctx = mlir.ir.Context()
-  a1 = ctx.parse_attr('"attr1"')
-  astr = mlir.ir.StringAttr(a1)
-  aself = mlir.ir.StringAttr(astr)
+  with Context():
+    a1 = Attribute.parse('"attr1"')
+    astr = StringAttr(a1)
+    aself = StringAttr(astr)
     # CHECK: Attribute("attr1")
     print(repr(astr))
     try:
-    tillegal = mlir.ir.StringAttr(ctx.parse_attr("1.0"))
+      tillegal = StringAttr(Attribute.parse("1.0"))
     except ValueError as e:
       # CHECK: ValueError: Cannot cast attribute to StringAttr (from Attribute(1.000000e+00 : f64))
       print("ValueError:", e)
     else:
       print("Exception not produced")
 
 run(testStandardAttrCasts)
 
 
 # CHECK-LABEL: TEST: testFloatAttr
 def testFloatAttr():
-  ctx = mlir.ir.Context()
-  fattr = mlir.ir.FloatAttr(ctx.parse_attr("42.0 : f32"))
+  with Context(), Location.unknown():
+    fattr = FloatAttr(Attribute.parse("42.0 : f32"))
     # CHECK: fattr value: 42.0
     print("fattr value:", fattr.value)
 
     # Test factory methods.
-  loc = ctx.get_unknown_location()
     # CHECK: default_get: 4.200000e+01 : f32
-  print("default_get:", mlir.ir.FloatAttr.get(
-      mlir.ir.F32Type.get(ctx), 42.0, loc))
+    print("default_get:", FloatAttr.get(
+        F32Type.get(), 42.0))
     # CHECK: f32_get: 4.200000e+01 : f32
-  print("f32_get:", mlir.ir.FloatAttr.get_f32(ctx, 42.0))
+    print("f32_get:", FloatAttr.get_f32(42.0))
     # CHECK: f64_get: 4.200000e+01 : f64
-  print("f64_get:", mlir.ir.FloatAttr.get_f64(ctx, 42.0))
+    print("f64_get:", FloatAttr.get_f64(42.0))
     try:
-    fattr_invalid = mlir.ir.FloatAttr.get(
-        mlir.ir.IntegerType.get_signless(ctx, 32), 42, loc)
+      fattr_invalid = FloatAttr.get(
+          IntegerType.get_signless(32), 42)
     except ValueError as e:
       # CHECK: invalid 'Type(i32)' and expected floating point type.
       print(e)
     else:
       print("Exception not produced")
 
 run(testFloatAttr)
 
 
 # CHECK-LABEL: TEST: testIntegerAttr
 def testIntegerAttr():
-  ctx = mlir.ir.Context()
-  iattr = mlir.ir.IntegerAttr(ctx.parse_attr("42"))
+  with Context() as ctx:
+    iattr = IntegerAttr(Attribute.parse("42"))
     # CHECK: iattr value: 42
     print("iattr value:", iattr.value)
     # CHECK: iattr type: i64
     print("iattr type:", iattr.type)
 
     # Test factory methods.
     # CHECK: default_get: 42 : i32
-  print("default_get:", mlir.ir.IntegerAttr.get(
-      mlir.ir.IntegerType.get_signless(ctx, 32), 42))
+    print("default_get:", IntegerAttr.get(
+        IntegerType.get_signless(32), 42))
 
 run(testIntegerAttr)
 
 
 # CHECK-LABEL: TEST: testBoolAttr
 def testBoolAttr():
-  ctx = mlir.ir.Context()
-  battr = mlir.ir.BoolAttr(ctx.parse_attr("true"))
+  with Context() as ctx:
+    battr = BoolAttr(Attribute.parse("true"))
     # CHECK: iattr value: 1
     print("iattr value:", battr.value)
 
     # Test factory methods.
     # CHECK: default_get: true
-  print("default_get:", mlir.ir.BoolAttr.get(ctx, True))
+    print("default_get:", BoolAttr.get(True))
 
 run(testBoolAttr)
 
 
 # CHECK-LABEL: TEST: testStringAttr
 def testStringAttr():
-  ctx = mlir.ir.Context()
-  sattr = mlir.ir.StringAttr(ctx.parse_attr('"stringattr"'))
+  with Context() as ctx:
+    sattr = StringAttr(Attribute.parse('"stringattr"'))
     # CHECK: sattr value: stringattr
     print("sattr value:", sattr.value)
 
     # Test factory methods.
     # CHECK: default_get: "foobar"
-  print("default_get:", mlir.ir.StringAttr.get(ctx, "foobar"))
+    print("default_get:", StringAttr.get("foobar"))
     # CHECK: typed_get: "12345" : i32
-  print("typed_get:", mlir.ir.StringAttr.get_typed(
-      mlir.ir.IntegerType.get_signless(ctx, 32), "12345"))
+    print("typed_get:", StringAttr.get_typed(
+        IntegerType.get_signless(32), "12345"))
 
 run(testStringAttr)
 
 
 # CHECK-LABEL: TEST: testNamedAttr
 def testNamedAttr():
-  ctx = mlir.ir.Context()
-  a = ctx.parse_attr('"stringattr"')
+  with Context():
+    a = Attribute.parse('"stringattr"')
     named = a.get_named("foobar")  # Note: under the small object threshold
     # CHECK: attr: "stringattr"
     print("attr:", named.attr)
     # CHECK: name: foobar
     print("name:", named.name)
     # CHECK: named: NamedAttribute(foobar="stringattr")
     print("named:", named)
 
 run(testNamedAttr)

mlir/test/Bindings/Python/ir_location.py

 # RUN: %PYTHON %s | FileCheck %s
 
 import gc
-import mlir
+from mlir.ir import *
 
 def run(f):
   print("\nTEST:", f.__name__)
   f()
   gc.collect()
-  assert mlir.ir.Context._get_live_count() == 0
+  assert Context._get_live_count() == 0
 
 
 # CHECK-LABEL: TEST: testUnknown
 def testUnknown():
-  ctx = mlir.ir.Context()
-  loc = ctx.get_unknown_location()
+  with Context() as ctx:
+    loc = Location.unknown()
   assert loc.context is ctx
   ctx = None
   gc.collect()
   # CHECK: unknown str: loc(unknown)
   print("unknown str:", str(loc))
   # CHECK: unknown repr: loc(unknown)
   print("unknown repr:", repr(loc))
 
 run(testUnknown)
 
 
 # CHECK-LABEL: TEST: testFileLineCol
 def testFileLineCol():
-  ctx = mlir.ir.Context()
-  loc = ctx.get_file_location("foo.txt", 123, 56)
+  with Context() as ctx:
+    loc = Location.file("foo.txt", 123, 56)
   ctx = None
   gc.collect()
   # CHECK: file str: loc("foo.txt":123:56)
   print("file str:", str(loc))
   # CHECK: file repr: loc("foo.txt":123:56)
   print("file repr:", repr(loc))
 
 run(testFileLineCol)
 

mlir/test/Bindings/Python/ir_module.py

 # RUN: %PYTHON %s | FileCheck %s
 
 import gc
-import mlir
+from mlir.ir import *
 
 def run(f):
   print("\nTEST:", f.__name__)
   f()
   gc.collect()
-  assert mlir.ir.Context._get_live_count() == 0
+  assert Context._get_live_count() == 0
 
 
 # Verify successful parse.
 # CHECK-LABEL: TEST: testParseSuccess
 # CHECK: module @successfulParse
 def testParseSuccess():
-  ctx = mlir.ir.Context()
-  module = ctx.parse_module(r"""module @successfulParse {}""")
+  ctx = Context()
+  module = Module.parse(r"""module @successfulParse {}""", ctx)
   assert module.context is ctx
   print("CLEAR CONTEXT")
   ctx = None  # Ensure that module captures the context.
   gc.collect()
   module.dump()  # Just outputs to stderr. Verifies that it functions.
   print(str(module))
 
 run(testParseSuccess)
 
 
 # Verify parse error.
 # CHECK-LABEL: TEST: testParseError
 # CHECK: testParseError: Unable to parse module assembly (see diagnostics)
 def testParseError():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   try:
-    module = ctx.parse_module(r"""}SYNTAX ERROR{""")
+    module = Module.parse(r"""}SYNTAX ERROR{""", ctx)
   except ValueError as e:
     print("testParseError:", e)
   else:
     print("Exception not produced")
 
 run(testParseError)
 
 
 # Verify successful parse.
 # CHECK-LABEL: TEST: testCreateEmpty
 # CHECK: module {
 def testCreateEmpty():
-  ctx = mlir.ir.Context()
-  loc = ctx.get_unknown_location()
-  module = ctx.create_module(loc)
+  ctx = Context()
+  loc = Location.unknown(ctx)
+  module = Module.create(loc)
   print("CLEAR CONTEXT")
   ctx = None  # Ensure that module captures the context.
   gc.collect()
   print(str(module))
 
 run(testCreateEmpty)
 
 
 # Verify round-trip of ASM that contains unicode.
 # Note that this does not test that the print path converts unicode properly
 # because MLIR asm always normalizes it to the hex encoding.
 # CHECK-LABEL: TEST: testRoundtripUnicode
 # CHECK: func @roundtripUnicode()
 # CHECK: foo = "\F0\9F\98\8A"
 def testRoundtripUnicode():
-  ctx = mlir.ir.Context()
-  module = ctx.parse_module(r"""
+  ctx = Context()
+  module = Module.parse(r"""
     func @roundtripUnicode() attributes { foo = "😊" }
-  """)
+  """, ctx)
   print(str(module))
 
 run(testRoundtripUnicode)
 
 
 # Tests that module.operation works and correctly interns instances.
 # CHECK-LABEL: TEST: testModuleOperation
 def testModuleOperation():
-  ctx = mlir.ir.Context()
-  module = ctx.parse_module(r"""module @successfulParse {}""")
+  ctx = Context()
+  module = Module.parse(r"""module @successfulParse {}""", ctx)
   assert ctx._get_live_module_count() == 1
   op1 = module.operation
   assert ctx._get_live_operation_count() == 1
   # CHECK: module @successfulParse
   print(op1)
 
   # Ensure that operations are the same on multiple calls.
   op2 = module.operation
def testModuleOperation():
   assert ctx._get_live_operation_count() == 0
   assert ctx._get_live_module_count() == 0
 
 run(testModuleOperation)
 
 
 # CHECK-LABEL: TEST: testModuleCapsule
 def testModuleCapsule():
-  ctx = mlir.ir.Context()
-  module = ctx.parse_module(r"""module @successfulParse {}""")
+  ctx = Context()
+  module = Module.parse(r"""module @successfulParse {}""", ctx)
   assert ctx._get_live_module_count() == 1
   # CHECK: "mlir.ir.Module._CAPIPtr"
   module_capsule = module._CAPIPtr
   print(module_capsule)
-  module_dup = mlir.ir.Module._CAPICreate(module_capsule)
+  module_dup = Module._CAPICreate(module_capsule)
   assert module is module_dup
   assert module_dup.context is ctx
   # Gc and verify destructed.
   module = None
   module_capsule = None
   module_dup = None
   gc.collect()
   assert ctx._get_live_module_count() == 0
 
 
 run(testModuleCapsule)

mlir/test/Bindings/Python/ir_operation.py

 # RUN: %PYTHON %s | FileCheck %s
 
 import gc
 import io
 import itertools
-import mlir
+from mlir.ir import *
 
 def run(f):
   print("\nTEST:", f.__name__)
   f()
   gc.collect()
-  assert mlir.ir.Context._get_live_count() == 0
+  assert Context._get_live_count() == 0
 
 
 # Verify iterator based traversal of the op/region/block hierarchy.
 # CHECK-LABEL: TEST: testTraverseOpRegionBlockIterators
 def testTraverseOpRegionBlockIterators():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   ctx.allow_unregistered_dialects = True
-  module = ctx.parse_module(r"""
+  module = Module.parse(r"""
     func @f1(%arg0: i32) -> i32 {
       %1 = "custom.addi"(%arg0, %arg0) : (i32, i32) -> i32
       return %1 : i32
     }
-  """)
+  """, ctx)
   op = module.operation
   assert op.context is ctx
   # Get the block using iterators off of the named collections.
   regions = list(op.regions)
   blocks = list(regions[0].blocks)
   # CHECK: MODULE REGIONS=1 BLOCKS=1
   print(f"MODULE REGIONS={len(regions)} BLOCKS={len(blocks)}")
 
def testTraverseOpRegionBlockIterators():
   walk_operations("", op)
 
 run(testTraverseOpRegionBlockIterators)
 
 
 # Verify index based traversal of the op/region/block hierarchy.
 # CHECK-LABEL: TEST: testTraverseOpRegionBlockIndices
 def testTraverseOpRegionBlockIndices():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   ctx.allow_unregistered_dialects = True
-  module = ctx.parse_module(r"""
+  module = Module.parse(r"""
     func @f1(%arg0: i32) -> i32 {
       %1 = "custom.addi"(%arg0, %arg0) : (i32, i32) -> i32
       return %1 : i32
     }
-  """)
+  """, ctx)
 
   def walk_operations(indent, op):
     for i in range(len(op.regions)):
       region = op.regions[i]
       print(f"{indent}REGION {i}:")
       for j in range(len(region.blocks)):
         block = region.blocks[j]
         print(f"{indent}  BLOCK {j}:")
def testTraverseOpRegionBlockIndices():
   # CHECK:    OP 1: "module_terminator"
   walk_operations("", module.operation)
 
 run(testTraverseOpRegionBlockIndices)
 
 
 # CHECK-LABEL: TEST: testBlockArgumentList
 def testBlockArgumentList():
-  ctx = mlir.ir.Context()
-  module = ctx.parse_module(r"""
+  with Context() as ctx:
+    module = Module.parse(r"""
       func @f1(%arg0: i32, %arg1: f64, %arg2: index) {
         return
       }
-  """)
+    """, ctx)
     func = module.body.operations[0]
     entry_block = func.regions[0].blocks[0]
     assert len(entry_block.arguments) == 3
     # CHECK: Argument 0, type i32
     # CHECK: Argument 1, type f64
     # CHECK: Argument 2, type index
     for arg in entry_block.arguments:
       print(f"Argument {arg.arg_number}, type {arg.type}")
-    new_type = mlir.ir.IntegerType.get_signless(ctx, 8 * (arg.arg_number + 1))
+      new_type = IntegerType.get_signless(8 * (arg.arg_number + 1))
       arg.set_type(new_type)
 
     # CHECK: Argument 0, type i8
     # CHECK: Argument 1, type i16
     # CHECK: Argument 2, type i24
     for arg in entry_block.arguments:
       print(f"Argument {arg.arg_number}, type {arg.type}")
 
 
 run(testBlockArgumentList)
 
 
 # CHECK-LABEL: TEST: testDetachedOperation
 def testDetachedOperation():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   ctx.allow_unregistered_dialects = True
-  loc = ctx.get_unknown_location()
-  i32 = mlir.ir.IntegerType.get_signed(ctx, 32)
-  op1 = ctx.create_operation(
-      "custom.op1", loc, results=[i32, i32], regions=1, attributes={
-          "foo": mlir.ir.StringAttr.get(ctx, "foo_value"),
-          "bar": mlir.ir.StringAttr.get(ctx, "bar_value"),
+  with Location.unknown(ctx):
+    i32 = IntegerType.get_signed(32)
+    op1 = Operation.create(
+        "custom.op1", results=[i32, i32], regions=1, attributes={
+            "foo": StringAttr.get("foo_value"),
+            "bar": StringAttr.get("bar_value"),
         })
     # CHECK: %0:2 = "custom.op1"() ( {
     # CHECK: }) {bar = "bar_value", foo = "foo_value"} : () -> (si32, si32)
     print(op1)
 
   # TODO: Check successors once enough infra exists to do it properly.
 
 run(testDetachedOperation)
 
 
 # CHECK-LABEL: TEST: testOperationInsertionPoint
 def testOperationInsertionPoint():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   ctx.allow_unregistered_dialects = True
-  module = ctx.parse_module(r"""
+  module = Module.parse(r"""
     func @f1(%arg0: i32) -> i32 {
       %1 = "custom.addi"(%arg0, %arg0) : (i32, i32) -> i32
       return %1 : i32
     }
-  """)
+  """, ctx)
 
   # Create test op.
-  loc = ctx.get_unknown_location()
-  op1 = ctx.create_operation("custom.op1", loc)
-  op2 = ctx.create_operation("custom.op2", loc)
+  with Location.unknown(ctx):
+    op1 = Operation.create("custom.op1")
+    op2 = Operation.create("custom.op2")
 
     func = module.body.operations[0]
     entry_block = func.regions[0].blocks[0]
-  ip = mlir.ir.InsertionPoint.at_block_begin(entry_block)
+    ip = InsertionPoint.at_block_begin(entry_block)
     ip.insert(op1)
     ip.insert(op2)
     # CHECK: func @f1
     # CHECK: "custom.op1"()
     # CHECK: "custom.op2"()
     # CHECK: %0 = "custom.addi"
     print(module)
 
   # Trying to add a previously added op should raise.
   try:
     ip.insert(op1)
   except ValueError:
     pass
   else:
     assert False, "expected insert of attached op to raise"
 
 run(testOperationInsertionPoint)
 
 
 # CHECK-LABEL: TEST: testOperationWithRegion
 def testOperationWithRegion():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   ctx.allow_unregistered_dialects = True
-  loc = ctx.get_unknown_location()
-  i32 = mlir.ir.IntegerType.get_signed(ctx, 32)
-  op1 = ctx.create_operation("custom.op1", loc, regions=1)
+  with Location.unknown(ctx):
+    i32 = IntegerType.get_signed(32)
+    op1 = Operation.create("custom.op1", regions=1)
     block = op1.regions[0].blocks.append(i32, i32)
     # CHECK: "custom.op1"() ( {
     # CHECK: ^bb0(%arg0: si32, %arg1: si32):  // no predecessors
     # CHECK:   "custom.terminator"() : () -> ()
     # CHECK: }) : () -> ()
-  terminator = ctx.create_operation("custom.terminator", loc)
-  ip = mlir.ir.InsertionPoint(block)
+    terminator = Operation.create("custom.terminator")
+    ip = InsertionPoint(block)
     ip.insert(terminator)
     print(op1)
 
     # Now add the whole operation to another op.
     # TODO: Verify lifetime hazard by nulling out the new owning module and
     # accessing op1.
     # TODO: Also verify accessing the terminator once both parents are nulled
     # out.
-  module = ctx.parse_module(r"""
+    module = Module.parse(r"""
       func @f1(%arg0: i32) -> i32 {
         %1 = "custom.addi"(%arg0, %arg0) : (i32, i32) -> i32
         return %1 : i32
       }
     """)
     func = module.body.operations[0]
     entry_block = func.regions[0].blocks[0]
-  ip = mlir.ir.InsertionPoint.at_block_begin(entry_block)
+    ip = InsertionPoint.at_block_begin(entry_block)
     ip.insert(op1)
     # CHECK: func @f1
     # CHECK: "custom.op1"()
     # CHECK:   "custom.terminator"
     # CHECK: %0 = "custom.addi"
     print(module)
 
 run(testOperationWithRegion)
 
 
 # CHECK-LABEL: TEST: testOperationResultList
 def testOperationResultList():
-  ctx = mlir.ir.Context()
-  module = ctx.parse_module(r"""
+  ctx = Context()
+  module = Module.parse(r"""
     func @f1() {
       %0:3 = call @f2() : () -> (i32, f64, index)
       return
     }
     func @f2() -> (i32, f64, index)
-  """)
+  """, ctx)
   caller = module.body.operations[0]
   call = caller.regions[0].blocks[0].operations[0]
   assert len(call.results) == 3
   # CHECK: Result 0, type i32
   # CHECK: Result 1, type f64
   # CHECK: Result 2, type index
   for res in call.results:
     print(f"Result {res.result_number}, type {res.type}")
 
 
 run(testOperationResultList)
 
 
 # CHECK-LABEL: TEST: testOperationPrint
 def testOperationPrint():
-  ctx = mlir.ir.Context()
-  module = ctx.parse_module(r"""
+  ctx = Context()
+  module = Module.parse(r"""
     func @f1(%arg0: i32) -> i32 {
       %0 = constant dense<[1, 2, 3, 4]> : tensor<4xi32>
       return %arg0 : i32
     }
-  """)
+  """, ctx)
 
   # Test print to stdout.
   # CHECK: return %arg0 : i32
   module.operation.print()
 
   # Test print to text file.
   f = io.StringIO()
   # CHECK: <class 'str'>

mlir/test/Bindings/Python/ir_types.py

 # RUN: %PYTHON %s | FileCheck %s
 
 import gc
-import mlir
+from mlir.ir import *
 
 def run(f):
   print("\nTEST:", f.__name__)
   f()
   gc.collect()
-  assert mlir.ir.Context._get_live_count() == 0
+  assert Context._get_live_count() == 0
 
 
 # CHECK-LABEL: TEST: testParsePrint
 def testParsePrint():
-  ctx = mlir.ir.Context()
-  t = ctx.parse_type("i32")
+  ctx = Context()
+  t = Type.parse("i32", ctx)
   assert t.context is ctx
   ctx = None
   gc.collect()
   # CHECK: i32
   print(str(t))
   # CHECK: Type(i32)
   print(repr(t))
 
 run(testParsePrint)
 
 
 # CHECK-LABEL: TEST: testParseError
 # TODO: Hook the diagnostic manager to capture a more meaningful error
 # message.
 def testParseError():
-  ctx = mlir.ir.Context()
+  ctx = Context()
   try:
-    t = ctx.parse_type("BAD_TYPE_DOES_NOT_EXIST")
+    t = Type.parse("BAD_TYPE_DOES_NOT_EXIST", ctx)
   except ValueError as e:
     # CHECK: Unable to parse type: 'BAD_TYPE_DOES_NOT_EXIST'
     print("testParseError:", e)
   else:
     print("Exception not produced")
 
 run(testParseError)
 
 
 # CHECK-LABEL: TEST: testTypeEq
 def testTypeEq():
-  ctx = mlir.ir.Context()
-  t1 = ctx.parse_type("i32")
-  t2 = ctx.parse_type("f32")
-  t3 = ctx.parse_type("i32")
+  ctx = Context()
+  t1 = Type.parse("i32", ctx)
+  t2 = Type.parse("f32", ctx)
+  t3 = Type.parse("i32", ctx)
   # CHECK: t1 == t1: True
   print("t1 == t1:", t1 == t1)
   # CHECK: t1 == t2: False
   print("t1 == t2:", t1 == t2)
   # CHECK: t1 == t3: True
   print("t1 == t3:", t1 == t3)
   # CHECK: t1 == None: False
   print("t1 == None:", t1 == None)
 
 run(testTypeEq)
 
 
 # CHECK-LABEL: TEST: testTypeEqDoesNotRaise
 def testTypeEqDoesNotRaise():
-  ctx = mlir.ir.Context()
-  t1 = ctx.parse_type("i32")
+  ctx = Context()
+  t1 = Type.parse("i32", ctx)
   not_a_type = "foo"
   # CHECK: False
   print(t1 == not_a_type)
   # CHECK: False
   print(t1 == None)
   # CHECK: True
   print(t1 != None)
 
 run(testTypeEqDoesNotRaise)
 
 
 # CHECK-LABEL: TEST: testStandardTypeCasts
 def testStandardTypeCasts():
-  ctx = mlir.ir.Context()
-  t1 = ctx.parse_type("i32")
-  tint = mlir.ir.IntegerType(t1)
-  tself = mlir.ir.IntegerType(tint)
+  ctx = Context()
+  t1 = Type.parse("i32", ctx)
+  tint = IntegerType(t1)
+  tself = IntegerType(tint)
   # CHECK: Type(i32)
   print(repr(tint))
   try:
-    tillegal = mlir.ir.IntegerType(ctx.parse_type("f32"))
+    tillegal = IntegerType(Type.parse("f32", ctx))
   except ValueError as e:
     # CHECK: ValueError: Cannot cast type to IntegerType (from Type(f32))
     print("ValueError:", e)
   else:
     print("Exception not produced")
 
 run(testStandardTypeCasts)
 
 
 # CHECK-LABEL: TEST: testIntegerType
 def testIntegerType():
-  ctx = mlir.ir.Context()
-  i32 = mlir.ir.IntegerType(ctx.parse_type("i32"))
+  with Context() as ctx:
+    i32 = IntegerType(Type.parse("i32"))
     # CHECK: i32 width: 32
     print("i32 width:", i32.width)
     # CHECK: i32 signless: True
     print("i32 signless:", i32.is_signless)
     # CHECK: i32 signed: False
     print("i32 signed:", i32.is_signed)
     # CHECK: i32 unsigned: False
     print("i32 unsigned:", i32.is_unsigned)
 
-  s32 = mlir.ir.IntegerType(ctx.parse_type("si32"))
+    s32 = IntegerType(Type.parse("si32"))
     # CHECK: s32 signless: False
     print("s32 signless:", s32.is_signless)
     # CHECK: s32 signed: True
     print("s32 signed:", s32.is_signed)
     # CHECK: s32 unsigned: False
     print("s32 unsigned:", s32.is_unsigned)
 
-  u32 = mlir.ir.IntegerType(ctx.parse_type("ui32"))
+    u32 = IntegerType(Type.parse("ui32"))
     # CHECK: u32 signless: False
     print("u32 signless:", u32.is_signless)
     # CHECK: u32 signed: False
     print("u32 signed:", u32.is_signed)
     # CHECK: u32 unsigned: True
     print("u32 unsigned:", u32.is_unsigned)
 
     # CHECK: signless: i16
-  print("signless:", mlir.ir.IntegerType.get_signless(ctx, 16))
+    print("signless:", IntegerType.get_signless(16))
     # CHECK: signed: si8
-  print("signed:", mlir.ir.IntegerType.get_signed(ctx, 8))
+    print("signed:", IntegerType.get_signed(8))
     # CHECK: unsigned: ui64
-  print("unsigned:", mlir.ir.IntegerType.get_unsigned(ctx, 64))
+    print("unsigned:", IntegerType.get_unsigned(64))
 
 run(testIntegerType)
 
 # CHECK-LABEL: TEST: testIndexType
 def testIndexType():
-  ctx = mlir.ir.Context()
+  with Context() as ctx:
     # CHECK: index type: index
-  print("index type:", mlir.ir.IndexType.get(ctx))
+    print("index type:", IndexType.get())
 
 run(testIndexType)
 
 # CHECK-LABEL: TEST: testFloatType
 def testFloatType():
-  ctx = mlir.ir.Context()
+  with Context():
     # CHECK: float: bf16
-  print("float:", mlir.ir.BF16Type.get(ctx))
+    print("float:", BF16Type.get())
     # CHECK: float: f16
-  print("float:", mlir.ir.F16Type.get(ctx))
+    print("float:", F16Type.get())
     # CHECK: float: f32
-  print("float:", mlir.ir.F32Type.get(ctx))
+    print("float:", F32Type.get())
     # CHECK: float: f64
-  print("float:", mlir.ir.F64Type.get(ctx))
+    print("float:", F64Type.get())
 
 run(testFloatType)
 
 # CHECK-LABEL: TEST: testNoneType
 def testNoneType():
-  ctx = mlir.ir.Context()
+  with Context():
     # CHECK: none type: none
-  print("none type:", mlir.ir.NoneType.get(ctx))
+    print("none type:", NoneType.get())
 
 run(testNoneType)
 
 # CHECK-LABEL: TEST: testComplexType
 def testComplexType():
-  ctx = mlir.ir.Context()
-  complex_i32 = mlir.ir.ComplexType(ctx.parse_type("complex<i32>"))
+  with Context() as ctx:
+    complex_i32 = ComplexType(Type.parse("complex<i32>"))
     # CHECK: complex type element: i32
     print("complex type element:", complex_i32.element_type)
 
-  f32 = mlir.ir.F32Type.get(ctx)
+    f32 = F32Type.get()
     # CHECK: complex type: complex<f32>
-  print("complex type:", mlir.ir.ComplexType.get(f32))
+    print("complex type:", ComplexType.get(f32))
 
-  index = mlir.ir.IndexType.get(ctx)
+    index = IndexType.get()
     try:
-    complex_invalid = mlir.ir.ComplexType.get(index)
+      complex_invalid = ComplexType.get(index)
     except ValueError as e:
       # CHECK: invalid 'Type(index)' and expected floating point or integer type.
       print(e)
     else:
       print("Exception not produced")
 
 run(testComplexType)
 
 # CHECK-LABEL: TEST: testConcreteShapedType
 # Shaped type is not a kind of standard types, it is the base class for
 # vectors, memrefs and tensors, so this test case uses an instance of vector
 # to test the shaped type. The class hierarchy is preserved on the python side.
 def testConcreteShapedType():
-  ctx = mlir.ir.Context()
-  vector = mlir.ir.VectorType(ctx.parse_type("vector<2x3xf32>"))
+  with Context() as ctx:
+    vector = VectorType(Type.parse("vector<2x3xf32>"))
     # CHECK: element type: f32
     print("element type:", vector.element_type)
     # CHECK: whether the given shaped type is ranked: True
     print("whether the given shaped type is ranked:", vector.has_rank)
     # CHECK: rank: 2
     print("rank:", vector.rank)
     # CHECK: whether the shaped type has a static shape: True
     print("whether the shaped type has a static shape:", vector.has_static_shape)
     # CHECK: whether the dim-th dimension is dynamic: False
     print("whether the dim-th dimension is dynamic:", vector.is_dynamic_dim(0))
     # CHECK: dim size: 3
     print("dim size:", vector.get_dim_size(1))
     # CHECK: is_dynamic_size: False
     print("is_dynamic_size:", vector.is_dynamic_size(3))
     # CHECK: is_dynamic_stride_or_offset: False
     print("is_dynamic_stride_or_offset:", vector.is_dynamic_stride_or_offset(1))
     # CHECK: isinstance(ShapedType): True
-  print("isinstance(ShapedType):", isinstance(vector, mlir.ir.ShapedType))
+    print("isinstance(ShapedType):", isinstance(vector, ShapedType))
 
 run(testConcreteShapedType)
 
 # CHECK-LABEL: TEST: testAbstractShapedType
 # Tests that ShapedType operates as an abstract base class of a concrete
 # shaped type (using vector as an example).
 def testAbstractShapedType():
-  ctx = mlir.ir.Context()
-  vector = mlir.ir.ShapedType(ctx.parse_type("vector<2x3xf32>"))
+  ctx = Context()
+  vector = ShapedType(Type.parse("vector<2x3xf32>", ctx))
   # CHECK: element type: f32
   print("element type:", vector.element_type)
 
 run(testAbstractShapedType)
 
 # CHECK-LABEL: TEST: testVectorType
 def testVectorType():
-  ctx = mlir.ir.Context()
-  f32 = mlir.ir.F32Type.get(ctx)
+  with Context(), Location.unknown():
+    f32 = F32Type.get()
     shape = [2, 3]
-  loc = ctx.get_unknown_location()
     # CHECK: vector type: vector<2x3xf32>
-  print("vector type:", mlir.ir.VectorType.get(shape, f32, loc))
+    print("vector type:", VectorType.get(shape, f32))
 
-  none = mlir.ir.NoneType.get(ctx)
+    none = NoneType.get()
     try:
-    vector_invalid = mlir.ir.VectorType.get(shape, none, loc)
+      vector_invalid = VectorType.get(shape, none)
     except ValueError as e:
       # CHECK: invalid 'Type(none)' and expected floating point or integer type.
       print(e)
     else:
       print("Exception not produced")
 
 run(testVectorType)
 
 # CHECK-LABEL: TEST: testRankedTensorType
 def testRankedTensorType():
-  ctx = mlir.ir.Context()
-  f32 = mlir.ir.F32Type.get(ctx)
+  with Context(), Location.unknown():
+    f32 = F32Type.get()
     shape = [2, 3]
-  loc = ctx.get_unknown_location()
+    loc = Location.unknown()
     # CHECK: ranked tensor type: tensor<2x3xf32>
     print("ranked tensor type:",
-        mlir.ir.RankedTensorType.get(shape, f32, loc))
+          RankedTensorType.get(shape, f32))
 
-  none = mlir.ir.NoneType.get(ctx)
+    none = NoneType.get()
     try:
-    tensor_invalid = mlir.ir.RankedTensorType.get(shape, none, loc)
+      tensor_invalid = RankedTensorType.get(shape, none)
     except ValueError as e:
       # CHECK: invalid 'Type(none)' and expected floating point, integer, vector
       # CHECK: or complex type.
       print(e)
     else:
       print("Exception not produced")
 
 run(testRankedTensorType)
 
 # CHECK-LABEL: TEST: testUnrankedTensorType
 def testUnrankedTensorType():
-  ctx = mlir.ir.Context()
-  f32 = mlir.ir.F32Type.get(ctx)
-  loc = ctx.get_unknown_location()
-  unranked_tensor = mlir.ir.UnrankedTensorType.get(f32, loc)
+  with Context(), Location.unknown():
+    f32 = F32Type.get()
+    loc = Location.unknown()
+    unranked_tensor = UnrankedTensorType.get(f32)
     # CHECK: unranked tensor type: tensor<*xf32>
     print("unranked tensor type:", unranked_tensor)
     try:
       invalid_rank = unranked_tensor.rank
     except ValueError as e:
       # CHECK: calling this method requires that the type has a rank.
       print(e)
     else:
       print("Exception not produced")
     try:
       invalid_is_dynamic_dim = unranked_tensor.is_dynamic_dim(0)
     except ValueError as e:
       # CHECK: calling this method requires that the type has a rank.
       print(e)
     else:
       print("Exception not produced")
     try:
       invalid_get_dim_size = unranked_tensor.get_dim_size(1)
     except ValueError as e:
       # CHECK: calling this method requires that the type has a rank.
       print(e)
     else:
       print("Exception not produced")
 
-  none = mlir.ir.NoneType.get(ctx)
+    none = NoneType.get()
     try:
-    tensor_invalid = mlir.ir.UnrankedTensorType.get(none, loc)
+      tensor_invalid = UnrankedTensorType.get(none)
     except ValueError as e:
       # CHECK: invalid 'Type(none)' and expected floating point, integer, vector
       # CHECK: or complex type.
       print(e)
     else:
       print("Exception not produced")
 
 run(testUnrankedTensorType)
 
 # CHECK-LABEL: TEST: testMemRefType
 def testMemRefType():
-  ctx = mlir.ir.Context()
-  f32 = mlir.ir.F32Type.get(ctx)
+  with Context(), Location.unknown():
+    f32 = F32Type.get()
     shape = [2, 3]
-  loc = ctx.get_unknown_location()
-  memref = mlir.ir.MemRefType.get_contiguous_memref(f32, shape, 2, loc)
+    loc = Location.unknown()
+    memref = MemRefType.get_contiguous_memref(f32, shape, 2)
     # CHECK: memref type: memref<2x3xf32, 2>
     print("memref type:", memref)
     # CHECK: number of affine layout maps: 0
     print("number of affine layout maps:", memref.num_affine_maps)
     # CHECK: memory space: 2
     print("memory space:", memref.memory_space)
 
-  none = mlir.ir.NoneType.get(ctx)
+    none = NoneType.get()
     try:
-    memref_invalid = mlir.ir.MemRefType.get_contiguous_memref(none, shape, 2,
-                                                              loc)
+      memref_invalid = MemRefType.get_contiguous_memref(none, shape, 2)
     except ValueError as e:
       # CHECK: invalid 'Type(none)' and expected floating point, integer, vector
       # CHECK: or complex type.
       print(e)
     else:
       print("Exception not produced")
 
 run(testMemRefType)
 
 # CHECK-LABEL: TEST: testUnrankedMemRefType
 def testUnrankedMemRefType():
-  ctx = mlir.ir.Context()
-  f32 = mlir.ir.F32Type.get(ctx)
-  loc = ctx.get_unknown_location()
-  unranked_memref = mlir.ir.UnrankedMemRefType.get(f32, 2, loc)
+  with Context(), Location.unknown():
+    f32 = F32Type.get()
+    loc = Location.unknown()
+    unranked_memref = UnrankedMemRefType.get(f32, 2)
     # CHECK: unranked memref type: memref<*xf32, 2>
     print("unranked memref type:", unranked_memref)
     try:
       invalid_rank = unranked_memref.rank
     except ValueError as e:
       # CHECK: calling this method requires that the type has a rank.
       print(e)
     else:
       print("Exception not produced")
     try:
       invalid_is_dynamic_dim = unranked_memref.is_dynamic_dim(0)
     except ValueError as e:
       # CHECK: calling this method requires that the type has a rank.
       print(e)
     else:
       print("Exception not produced")
     try:
       invalid_get_dim_size = unranked_memref.get_dim_size(1)
     except ValueError as e:
       # CHECK: calling this method requires that the type has a rank.
       print(e)
     else:
       print("Exception not produced")
 
-  none = mlir.ir.NoneType.get(ctx)
+    none = NoneType.get()
     try:
-    memref_invalid = mlir.ir.UnrankedMemRefType.get(none, 2, loc)
+      memref_invalid = UnrankedMemRefType.get(none, 2)
     except ValueError as e:
       # CHECK: invalid 'Type(none)' and expected floating point, integer, vector
       # CHECK: or complex type.
       print(e)
     else:
       print("Exception not produced")
 
 run(testUnrankedMemRefType)
 
 # CHECK-LABEL: TEST: testTupleType
 def testTupleType():
-  ctx = mlir.ir.Context()
-  i32 = mlir.ir.IntegerType(ctx.parse_type("i32"))
-  f32 = mlir.ir.F32Type.get(ctx)
-  vector = mlir.ir.VectorType(ctx.parse_type("vector<2x3xf32>"))
+  with Context() as ctx:
+    i32 = IntegerType(Type.parse("i32"))
+    f32 = F32Type.get()
+    vector = VectorType(Type.parse("vector<2x3xf32>"))
     l = [i32, f32, vector]
-  tuple_type = mlir.ir.TupleType.get_tuple(ctx, l)
+    tuple_type = TupleType.get_tuple(l)
     # CHECK: tuple type: tuple<i32, f32, vector<2x3xf32>>
     print("tuple type:", tuple_type)
     # CHECK: number of types: 3
     print("number of types:", tuple_type.num_types)
     # CHECK: pos-th type in the tuple type: f32
     print("pos-th type in the tuple type:", tuple_type.get_type(1))
 
 run(testTupleType)
 
 
 # CHECK-LABEL: TEST: testFunctionType
 def testFunctionType():
-  ctx = mlir.ir.Context()
-  input_types = [mlir.ir.IntegerType.get_signless(ctx, 32),
-                 mlir.ir.IntegerType.get_signless(ctx, 16)]
-  result_types = [mlir.ir.IndexType.get(ctx)]
-  func = mlir.ir.FunctionType.get(ctx, input_types, result_types)
+  with Context() as ctx:
+    input_types = [IntegerType.get_signless(32),
+                  IntegerType.get_signless(16)]
+    result_types = [IndexType.get()]
+    func = FunctionType.get(input_types, result_types)
     # CHECK: INPUTS: [Type(i32), Type(i16)]
     print("INPUTS:", func.inputs)
     # CHECK: RESULTS: [Type(index)]
     print("RESULTS:", func.results)
 
 
 run(testFunctionType)