This will support two syntax in python-defined dialects.
First is that traits can now be declared in class parameters, e.g.
```python
class ParentIsIfTrait(DynamicOpTrait): #define a python-side trait
@staticmethod
def verify_invariants(op) -> bool:
if not isinstance(op.parent.opview, IfOp):
op.location.emit_error(
f"{op.name} should be put inside {IfOp.OPERATION_NAME}"
)
return False
return True
class YieldOp( # attach two traits: IsTerminatorTrait, ParentIsIfTrait
TestRegion.Operation, name="yield", traits=[IsTerminatorTrait, ParentIsIfTrait]
):
...
```
Second is that users can directly define
`verify_invariants`/`verify_region_invariants` methods in the operation
to add additional custom verification logic. And this is implemented via
traits.
```python
class YieldOp(TestRegion.Operation, name="yield", ...):
value: Operand[Any]
def verify_invariants(self) -> bool: # define a method directly
if self.parent.results[0].type != self.value.type:
self.location.emit_error(
"result type mismatch between YieldOp and its parent IfOp"
)
return False
return True
```
Previously we use `verify`/`verify_region` as method names (in
yesterday's PR #179705), but in this PR they are renamed to
`verify_invariants`/`verify_region_invariants` because there are
conflicts between the newly-added `verify` method and `ir.OpView.verify`
method:
- `verify_invariants` is just to attach **additional** verification
logic. but `OpView.verify` is to construct an OperationVerifer and do
full verification for an operation, so the semantics is not same between
these two. We should not shadow the `OpView.verify` method by defining a
new semantically-different `verify` method.
- it will make users confuse between these two `verify` methods, since
they have different meaning.
- if users didn't define the `verify` method in their python-defined
operation, `DynamicOpTraits.attach(opname, MyOpCls)` still do the
attaching (because `hasattr("verify")` returns `True`) and seg fault
(because we cannot attach `OpView.verify`).
---------
Co-authored-by: Rolf Morel <rolfmorel@gmail.com>
This is a follow-up PR of #169045 and the second part of #179086.
In #179086, we added support for defining regions in Python-defined ops,
but its usefulness was quite limited because we still couldn’t mark an
op as a `Terminator` or `NoTerminator`. In this PR, we port the
`DynamicOpTrait` (introduced on the C++ side for `DynamicDialect` in
#177735) to Python, so we can dynamically attach traits to
Python-defined ops.
This PR adds basic support for defining regions in Python-defined
dialects. Example usage:
```python
class TestRegion(Dialect, name="ext_region"):
pass
class IfOp(TestRegion.Operation, name="if"):
cond: Operand[IntegerType[1]]
then: Region
else_: Region
```
Current limitations:
* We can’t specify region constraints yet (e.g., number of blocks or
block argument types). This will be addressed as a follow-up task.
* We can’t mark an op as a `Terminator` or `NoTerminator` yet. This
depends on `DynamicOpTraits` (#177735) and Python-side trait API
support, and will be implemented in a follow-up PR.
This is the first PR after splitting off #179032.
This is a follow-up PR of #169045.
---------
Co-authored-by: Rolf Morel <rolfmorel@gmail.com>
Python bindings for the IRDL dialect were introduced in #158488. They
are currently usable—for constructing IR and dynamically loading modules
that contain `irdl.dialect` into MLIR. However, there are still several
pain points when working with them:
* The IRDL IR-building interface is not very intuitive and tends to be
quite verbose.
* We do not yet have the corresponding `OpView` classes for IRDL-defined
operations.
To address these issues, I propose creating a wrapper (effectively a
small “DSL”) on top of the existing IRDL Python bindings. This wrapper
aims to simplify IR construction and automatically generate the
corresponding `OpView` types. A simple example is shown below.
Currently, using the IRDL bindings looks like this:
```python
m = Module.create()
with InsertionPoint(m.body):
myint = irdl.dialect("myint")
with InsertionPoint(myint.body):
constant = irdl.operation_("constant")
with InsertionPoint(constant.body):
iattr = irdl.base(base_name="#builtin.integer")
i32 = irdl.is_(TypeAttr.get(IntegerType.get_signless(32)))
irdl.attributes_([iattr], ["value"])
irdl.results_([i32], ["cst"], [irdl.Variadicity.single])
add = irdl.operation_("add")
with InsertionPoint(add.body):
i32 = irdl.is_(TypeAttr.get(IntegerType.get_signless(32)))
irdl.operands_(
[i32, i32],
["lhs", "rhs"],
[irdl.Variadicity.single, irdl.Variadicity.single],
)
irdl.results_([i32], ["res"], [irdl.Variadicity.single])
irdl.load_dialects(m)
```
With the proposed DSL (module name `mlir.dialects.ext`), the equivalent
implementation becomes:
```python
class MyInt(Dialect, name="myint"):
pass
i32 = IntegerType[32]
class ConstantOp(MyInt.Operation, name="constant"):
value: IntegerAttr
cst: Result[i32]
class AddOp(MyInt.Operation, name="add"):
lhs: Operand[i32]
rhs: Operand[i32]
res: Result[i32]
MyInt.load()
```
Compared with the current IRDL Python bindings, this DSL mainly adds the
following:
* **A more intuitive interface** for constructing IRDL definitions (as
shown in the example).
* **Automatic generation of the corresponding `OpView`
classes**—including `__init__` methods and property getters for each
defined operation. Similar to TableGen’s `ins`, operands and attributes
can be interleaved in arbitrary order. Special handling is also
implemented for optional and variadic operands/results (such as
computing segment sizes) so that they feel as natural to use as native
operations.
* **Lazy insertion of ops**: all ops are created and inserted only when
`Dialect.load()` is called, which makes it unnecessary to specify an
MLIR context immediately when defining an IRDL dialect.
* **Basic type inference** in operation builders (i.e.
`OpViewCls.__init__`) for trivial result types.
The current DSL does not yet cover all IRDL operations. Several features
are not supported at the moment:
- Defining new types or attributes
- Parametric constraints
- Adding regions to operations
---------
Co-authored-by: Rolf Morel <rolfmorel@gmail.com>