* 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.
Differential Revision: https://reviews.llvm.org/D90547
* Extends Context/Operation interning to cover Module as well.
* Implements Module.context, Attribute.context, Type.context, and Location.context back-references (facilitated testing and also on the TODO list).
* Adds method to create an empty Module.
* Discovered missing in npcomp.
Differential Revision: https://reviews.llvm.org/D89294
* Providing stable, C-accessible definitions for bridging MLIR Python<->C APIs, we eliminate inter-extension dependencies (i.e. they can all share a diamond dependency on the MLIR C-API).
* Just provides accessors for context and module right now.
* Needed in NPComp in ~a week or so for high level Torch APIs.
Differential Revision: https://reviews.llvm.org/D88426
* Fixes a rather egregious bug with respect to the inability to return arbitrary objects from py::init (was causing aliasing of multiple py::object -> native instance).
* Makes Modules and Operations referencable types so that they can be reliably depended on.
* Uniques python operation instances within a context. Opens the door for further accounting.
* Next I will retrofit region and block to be dependent on the operation, and I will attempt to model the API to avoid detached regions/blocks, which will simplify things a lot (in that world, only operations can be detached).
* Added quite a bit of test coverage to check for leaks and reference issues.
* Supercedes: https://reviews.llvm.org/D87213
Differential Revision: https://reviews.llvm.org/D87958
* The binding for Type is trivial and should be non-controversial.
* The way that I define the IntegerType should serve as a pattern for what I want to do next.
* I propose defining the rest of the standard types in this fashion and then generalizing for dialect types as necessary.
* Essentially, creating/accessing a concrete Type (vs interacting with the string form) is done by "casting" to the concrete type (i.e. IntegerType can be constructed with a Type and will throw if the cast is illegal).
* This deviates from some of our previous discussions about global objects but I think produces a usable API and we should go this way.
Differential Revision: https://reviews.llvm.org/D86179
