Commit Graph

8 Commits

Author SHA1 Message Date
Lei Zhang 8f5fa56623 [TableGen] Consolidate constraint related concepts
Previously we have multiple mechanisms to specify op definition and match constraints:
TypeConstraint, AttributeConstraint, Type, Attr, mAttr, mAttrAnyOf, mPat. These variants
are not added because there are so many distinct cases we need to model; essentially,
they are all carrying a predicate. It's just an artifact of implementation.

It's quite confusing for users to grasp these variants and choose among them. Instead,
as the OpBase TableGen file, we need to strike to provide an unified mechanism. Each
dialect has the flexibility to define its own aliases if wanted.

This CL removes mAttr, mAttrAnyOf, mPat. A new base class, Constraint, is added. Now
TypeConstraint and AttrConstraint derive from Constraint. Type and Attr further derive
from TypeConstraint and AttrConstraint, respectively.

Comments are revised and examples are added to make it clear how to use constraints.

PiperOrigin-RevId: 240125076
2019-03-29 17:38:46 -07:00
Feng Liu c52a812700 [TableGen] Support nested dag attributes arguments in the result pattern
Add support to create a new attribute from multiple attributes. It extended the
DagNode class to represent attribute creation dag. It also changed the
RewriterGen::emitOpCreate method to support this nested dag emit.

An unit test is added.

PiperOrigin-RevId: 238090229
2019-03-29 17:15:57 -07:00
Lei Zhang 18fde7c9d8 [TableGen] Support multiple result patterns
This CL added the ability to generate multiple ops using multiple result
patterns, with each of them replacing one result of the matched source op.

Specifically, the syntax is

```
def : Pattern<(SourceOp ...),
              [(ResultOp1 ...), (ResultOp2 ...), (ResultOp3 ...)]>;
```

Assuming `SourceOp` has three results.

Currently we require that each result op must generate one result, which
can be lifted later when use cases arise.

To help with cases that certain output is unused and we don't care about it,
this CL also introduces a new directive: `verifyUnusedValue`. Checks will
be emitted in the `match()` method to make sure if the corresponding output
is not unused, `match()` returns with `matchFailure()`.

PiperOrigin-RevId: 237513904
2019-03-29 17:07:50 -07:00
Jacques Pienaar 388fb3751e Add pattern constraints.
Enable matching pattern only if constraint is met. Start with type constraints and more general C++ constraints.

PiperOrigin-RevId: 233830768
2019-03-29 16:26:53 -07:00
Lei Zhang a57b398906 [TableGen] Assign created ops to variables and rewrite with PatternRewriter::replaceOp()
Previously we were using PatternRewrite::replaceOpWithNewOp() to both create the new op
inline and rewrite the matched op. That does not work well if we want to generate multiple
ops in a sequence. To support that, this CL changed to assign each newly created op to a
separate variable.

This CL also refactors how PatternEmitter performs the directive dispatch logic.

PiperOrigin-RevId: 233206819
2019-03-29 16:22:53 -07:00
Lei Zhang e0774c008f [TableGen] Use tblgen::DagLeaf to model DAG arguments
This CL added a tblgen::DagLeaf wrapper class with several helper methods for handling
DAG arguments. It helps to refactor the rewriter generation logic to be more higher
level.

This CL also added a tblgen::ConstantAttr wrapper class for constant attributes.

PiperOrigin-RevId: 232050683
2019-03-29 16:06:31 -07:00
Jacques Pienaar 82dc6a878c Add fallback to native code op builder specification for patterns.
This allow for arbitrarily complex builder patterns which is meant to cover initial cases while the modelling is improved and long tail cases/cases for which expanding the DSL would result in worst overall system.

NFC just sorting the emit replace methods alphabetical in the class and file body.

PiperOrigin-RevId: 231890352
2019-03-29 16:04:53 -07:00
Lei Zhang eb753f4aec Add tblgen::Pattern to model Patterns defined in TableGen
Similar to other tblgen:: abstractions, tblgen::Pattern hides the native TableGen
API and provides a nicer API that is more coherent with the TableGen definitions.

PiperOrigin-RevId: 231285143
2019-03-29 15:41:38 -07:00