Since the very first commits, the Python and C MLIR APIs have had mis-placed registration/load functionality for dialects, extensions, etc. This was done pragmatically in order to get bootstrapped and then just grew in. Downstreams largely bypass and do their own thing by providing various APIs to register things they need. Meanwhile, the C++ APIs have stabilized around this and it would make sense to follow suit.
The thing we have observed in canonical usage by downstreams is that each downstream tends to have native entry points that configure its installation to its preferences with one-stop APIs. This patch leans in to this approach with `RegisterEverything.h` and `mlir._mlir_libs._mlirRegisterEverything` being the one-stop entry points for the "upstream packages". The `_mlir_libs.__init__.py` now allows customization of the environment and Context by adding "initialization modules" to the `_mlir_libs` package. If present, `_mlirRegisterEverything` is treated as such a module. Others can be added by downstreams by adding a `_site_initialize_{i}.py` module, where '{i}' is a number starting with zero. The number will be incremented and corresponding module loaded until one is not found. Initialization modules can:
* Perform load time customization to the global environment (i.e. registering passes, hooks, etc).
* Define a `register_dialects(registry: DialectRegistry)` function that can extend the `DialectRegistry` that will be used to bootstrap the `Context`.
* Define a `context_init_hook(context: Context)` function that will be added to a list of callbacks which will be invoked after dialect registration during `Context` initialization.
Note that the `MLIRPythonExtension.RegisterEverything` is not included by default when building a downstream (its corresponding behavior was prior). For downstreams which need the default MLIR initialization to take place, they must add this back in to their Python CMake build just like they add their own components (i.e. to `add_mlir_python_common_capi_library` and `add_mlir_python_modules`). It is perfectly valid to not do this, in which case, only the things explicitly depended on and initialized by downstreams will be built/packaged. If the downstream has not been set up for this, it is recommended to simply add this back for the time being and pay the build time/package size cost.
CMake changes:
* `MLIRCAPIRegistration` -> `MLIRCAPIRegisterEverything` (renamed to signify what it does and force an evaluation: a number of places were incidentally linking this very expensive target)
* `MLIRPythonSoure.Passes` removed (without replacement: just drop)
* `MLIRPythonExtension.AllPassesRegistration` removed (without replacement: just drop)
* `MLIRPythonExtension.Conversions` removed (without replacement: just drop)
* `MLIRPythonExtension.Transforms` removed (without replacement: just drop)
Header changes:
* `mlir-c/Registration.h` is deleted. Dialect registration functionality is now in `IR.h`. Registration of upstream features are in `mlir-c/RegisterEverything.h`. When updating MLIR and a couple of downstreams, I found that proper usage was commingled so required making a choice vs just blind S&R.
Python APIs removed:
* mlir.transforms and mlir.conversions (previously only had an __init__.py which indirectly triggered `mlirRegisterTransformsPasses()` and `mlirRegisterConversionPasses()` respectively). Downstream impact: Remove these imports if present (they now happen as part of default initialization).
* mlir._mlir_libs._all_passes_registration, mlir._mlir_libs._mlirTransforms, mlir._mlir_libs._mlirConversions. Downstream impact: None expected (these were internally used).
C-APIs changed:
* mlirRegisterAllDialects(MlirContext) now takes an MlirDialectRegistry instead. It also used to trigger loading of all dialects, which was already marked with a TODO to remove -- it no longer does, and for direct use, dialects must be explicitly loaded. Downstream impact: Direct C-API users must ensure that needed dialects are loaded or call `mlirContextLoadAllAvailableDialects(MlirContext)` to emulate the prior behavior. Also see the `ir.c` test case (e.g. ` mlirContextGetOrLoadDialect(ctx, mlirStringRefCreateFromCString("func"));`).
* mlirDialectHandle* APIs were moved from Registration.h (which now is restricted to just global/upstream registration) to IR.h, arguably where it should have been. Downstream impact: include correct header (likely already doing so).
C-APIs added:
* mlirContextLoadAllAvailableDialects(MlirContext): Corresponds to C++ API with the same purpose.
Python APIs added:
* mlir.ir.DialectRegistry: Mapping for an MlirDialectRegistry.
* mlir.ir.Context.append_dialect_registry(MlirDialectRegistry)
* mlir.ir.Context.load_all_available_dialects()
* mlir._mlir_libs._mlirAllRegistration: New native extension that exposes a `register_dialects(MlirDialectRegistry)` entry point and performs all upstream pass/conversion/transforms registration on init. In this first step, we eagerly load this as part of the __init__.py and use it to monkey patch the Context to emulate prior behavior.
* Type caster and capsule support for MlirDialectRegistry
This should make it possible to build downstream Python dialects that only depend on a subset of MLIR. See: https://github.com/llvm/llvm-project/issues/56037
Here is an example PR, minimally adapting IREE to these changes: https://github.com/iree-org/iree/pull/9638/files In this situation, IREE is opting to not link everything, since it is already configuring the Context to its liking. For projects that would just like to not think about it and pull in everything, add `MLIRPythonExtension.RegisterEverything` to the list of Python sources getting built, and the old behavior will continue.
Reviewed By: mehdi_amini, ftynse
Differential Revision: https://reviews.llvm.org/D128593
Adds `mlirBlockDetach` to the CAPI to remove a block from its parent
region. Use it in the Python bindings to implement
`Block.append_to(region)`.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D123165
Adds the ability to create external passes using the C-API. This allows passes
to be written in C or languages that use the C-bindings.
Differential Revision: https://reviews.llvm.org/D121866
There is no reason for this file to be at the top-level, and
its current placement predates the Parser/ folder's existence.
Differential Revision: https://reviews.llvm.org/D121024
Exposes mlir::DialectRegistry to the C API as MlirDialectRegistry along with
helper functions. A hook has been added to MlirDialectHandle that inserts
the dialect into a registry.
A future possible change is removing mlirDialectHandleRegisterDialect in
favor of using mlirDialectHandleInsertDialect, which it is now implemented with.
Differential Revision: https://reviews.llvm.org/D118293
BlockArguments gained the ability to have locations attached a while ago, but they
have always been optional. This goes against the core tenant of MLIR where location
information is a requirement, so this commit updates the API to require locations.
Fixes#53279
Differential Revision: https://reviews.llvm.org/D117633
There have been a few API pieces remaining to allow for a smooth transition for
downstream users, but these have been up for a few months now. After this only
the C API will have reference to "Identifier", but those will be reworked in a followup.
The main updates are:
* Identifier -> StringAttr
* StringAttr::get requires the context as the first parameter
- i.e. `Identifier::get("...", ctx)` -> `StringAttr::get(ctx, "...")`
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D116626
* set_symbol_name, get_symbol_name, set_visibility, get_visibility, replace_all_symbol_uses, walk_symbol_tables
* In integrations I've been doing, I've been reaching for all of these to do both general IR manipulation and module merging.
* I don't love the replace_all_symbol_uses underlying APIs since they necessitate SYMBOL_COUNT walks and have various sharp edges. I'm hoping that whatever emerges eventually for this can still retain this simple API as a one-shot.
Differential Revision: https://reviews.llvm.org/D114687
NamedAttribute is currently represented as an std::pair, but this
creates an extremely clunky .first/.second API. This commit
converts it to a class, with better accessors (getName/getValue)
and also opens the door for more convenient API in the future.
Differential Revision: https://reviews.llvm.org/D113956
The current implementation is quite clunky; OperationName stores either an Identifier
or an AbstractOperation that corresponds to an operation. This has several problems:
* OperationNames created before and after an operation are registered are different
* Accessing the identifier name/dialect/etc. from an OperationName are overly branchy
- they need to dyn_cast a PointerUnion to check the state
This commit refactors this such that we create a single information struct for every
operation name, even operations that aren't registered yet. When an OperationName is
created for an unregistered operation, we only populate the name field. When the
operation is registered, we populate the remaining fields. With this we now have two
new classes: OperationName and RegisteredOperationName. These both point to the
same underlying operation information struct, but only RegisteredOperationName can
assume that the operation is actually registered. This leads to a much cleaner API, and
we can also move some AbstractOperation functionality directly to OperationName.
Differential Revision: https://reviews.llvm.org/D114049
Identifier and StringAttr essentially serve the same purpose, i.e. to hold a string value. Keeping these seemingly identical pieces of functionality separate has caused problems in certain situations:
* Identifier has nice accessors that StringAttr doesn't
* Identifier can't be used as an Attribute, meaning strings are often duplicated between Identifier/StringAttr (e.g. in PDL)
The only thing that Identifier has that StringAttr doesn't is support for caching a dialect that is referenced by the string (e.g. dialect.foo). This functionality is added to StringAttr, as this is useful for StringAttr in generally the same ways it was useful for Identifier.
Differential Revision: https://reviews.llvm.org/D113536
Enables using the same iterator interface to these even though underlying storage is different.
Differential Revision: https://reviews.llvm.org/D113512
Symbol tables are a largely useful top-level IR construct, for example, they
make it easy to access functions in a module by name instead of traversing the
list of module's operations to find the corresponding function.
Depends On D112886
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D112821
Provide support for removing an operation from the block that contains it and
moving it back to detached state. This allows for the operation to be moved to
a different block, a common IR manipulation for, e.g., module merging.
Also fix a potential one-past-end iterator dereference in Operation::moveAfter
discovered in the process.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D112700
Exposes mlir::TypeID to the C API as MlirTypeID along with various accessors
and helper functions.
Differential Revision: https://reviews.llvm.org/D110897
Add method to get NameLoc. Treat null child location as unknown to avoid
needing to create UnknownLoc in C API where child loc is not needed.
Differential Revision: https://reviews.llvm.org/D108678
* It is pretty clear that no one has tried this yet since it was both incomplete and broken.
* Fixes a symbol hiding issues keeping even the generic builder from constructing an operation with successors.
* Adds ODS support for successors.
* Adds CAPI `mlirBlockGetParentRegion`, `mlirRegionEqual` + tests (and missing test for `mlirBlockGetParentOperation`).
* Adds Python property: `Block.region`.
* Adds Python methods: `Block.create_before` and `Block.create_after`.
* Adds Python property: `InsertionPoint.block`.
* Adds new blocks.py test to verify a plausible CFG construction case.
Differential Revision: https://reviews.llvm.org/D108898
At the moment `MlirModule`s can be converted to `MlirOperation`s, but not
the other way around (at least not without going around the C API). This
makes it impossible to e.g. run passes over a `ModuleOp` created through
`mlirOperationCreate`.
Reviewed By: nicolasvasilache, mehdi_amini
Differential Revision: https://reviews.llvm.org/D102497
This adds `mlirOperationSetOperand` to the IR C API, similar to the
function to get an operand.
In the Python API, this adds `operands[index] = value` syntax, similar
to the syntax to get an operand with `operands[index]`.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D101398
Expose the debug flag as a readable and assignable property of a
dedicated class instead of a write-only function. Actually test the fact
of setting the flag. Move test to a dedicated file, it has zero relation
to context_managers.py where it was added.
Arguably, it should be promoted from mlir.ir to mlir module, but we are
not re-exporting the latter and this functionality is purposefully
hidden so can stay in IR for now. Drop unnecessary export code.
Refactor C API and put Debug into a separate library, fix it to actually
set the flag to the given value.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D100757
These properties were useful for a few things before traits had a better integration story, but don't really carry their weight well these days. Most of these properties are already checked via traits in most of the code. It is better to align the system around traits, and improve the performance/cost of traits in general.
Differential Revision: https://reviews.llvm.org/D96088
* Adds a flag to MlirOperationState to enable result type inference using the InferTypeOpInterface.
* I chose this level of implementation for a couple of reasons:
a) In the creation flow is naturally where generated and custom builder code will be invoking such a thing
b) it is a bit more efficient to share the data structure and unpacking vs having a standalone entry-point
c) we can always decide to expose more of these interfaces with first-class APIs, but that doesn't preclude that we will always want to use this one in this way (and less API surface area for common things is better for API stability and evolution).
* I struggled to find an appropriate way to test it since we don't link the test dialect into anything CAPI accessible at present. I opted instead for one of the simplest ops I found in a regular dialect which implements the interface.
* This does not do any trait-based type selection. That will be left to generated tablegen wrappers.
Differential Revision: https://reviews.llvm.org/D95283
This class used to serve a few useful purposes:
* Allowed containing a null DictionaryAttr
* Provided some simple mutable API around a DictionaryAttr
The first of which is no longer an issue now that there is much better caching support for attributes in general, and a cache in the context for empty dictionaries. The second results in more trouble than it's worth because it mutates the internal dictionary on every action, leading to a potentially large number of dictionary copies. NamedAttrList is a much better alternative for the second use case, and should be modified as needed to better fit it's usage as a DictionaryAttrBuilder.
Differential Revision: https://reviews.llvm.org/D93442
This mirror the C++ API for NamedAttribute, and has the advantage or
internalizing earlier in the Context and not requiring the caller to
keep the StringRef alive beyong this call.
Differential Revision: https://reviews.llvm.org/D93133
This reduces the chances of segfault. While it is a good practice to ensure
robust custom printers, it is unfortunately common to have them crash on
invalid input.
Reviewed By: stellaraccident
Differential Revision: https://reviews.llvm.org/D92536
* Add capsule get/create for Attribute and Type, which already had capsule interop defined.
* Add capsule interop and get/create for Location.
* Add Location __eq__.
* Use get() and implicit cast to go from PyAttribute, PyType, PyLocation to MlirAttribute, MlirType, MlirLocation (bundled with this change because I didn't want to continue the pattern one more time).
Differential Revision: https://reviews.llvm.org/D92283
While this makes the unit tests a bit more verbose, this simplifies the creation of bindings because only the bidirectional mapping between the host language's string type and MlirStringRef need to be implemented.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D91905
These pointers do not need to be mutable. This has an affect that generated function signatures in the Swift bindings now use `UnsafePointer` instead of `UnsafeMutablePointer`.
Reviewed By: ftynse, mehdi_amini
Differential Revision: https://reviews.llvm.org/D91740
These includes have been deprecated in favor of BuiltinDialect.h, which contains the definitions of ModuleOp and FuncOp.
Differential Revision: https://reviews.llvm.org/D91572
Slicing, that is element access with `[being:end:step]` structure, is
a common Python idiom for sequence-like containers. It is also necessary
to support custom accessor for operations with variadic operands and
results (an operation an return a slice of its operands that correspond
to the given variadic group).
Add generic utility to support slicing in Python bindings and use it
for operation operands and results.
Depends On D90923
Reviewed By: stellaraccident, mehdi_amini
Differential Revision: https://reviews.llvm.org/D90936
This delegate the control of the buffering to the user of the API. This
seems like a safer option as messages are immediately propagated to the
user, which may lead to less surprising behavior during debugging for
instance.
In terms of performance, a user can add a buffered stream on the other
side of the callback.
Differential Revision: https://reviews.llvm.org/D90726