This patch removes the `type` field from `Attribute` along with the
`Attribute::getType` accessor.
Going forward, this means that attributes in MLIR will no longer have
types as a first-class concept. This patch lays the groundwork to
incrementally remove or refactor code that relies on generic attributes
being typed. The immediate impact will be on attributes that rely on
`Attribute` containing a type, such as `IntegerAttr`,
`DenseElementsAttr`, and `ml_program::ExternAttr`, which will now need
to define a type parameter on their storage classes. This will save
memory as all other attribute kinds will no longer contain a type.
Moreover, it will not be possible to generically query the type of an
attribute directly. This patch provides an attribute interface
`TypedAttr` that implements only one method, `getType`, which can be
used to generically query the types of attributes that implement the
interface. This interface can be used to retain the concept of a "typed
attribute". The ODS-generated accessor for a `type` parameter
automatically implements this method.
Next steps will be to refactor the assembly formats of certain operations
that rely on `parseAttribute(type)` and `printAttributeWithoutType` to
remove special handling of type elision until `type` can be removed from
the dialect parsing hook entirely; and incrementally remove uses of
`TypedAttr`.
Reviewed By: lattner, rriddle, jpienaar
Differential Revision: https://reviews.llvm.org/D130092
The current implementation uses a discrete "pdl_interp.inferred_types"
operation, which acts as a "fake" handle to a type range. This op is
used as a signal to pdl_interp.create_operation that types should be
inferred. This is terribly awkward and clunky though:
* This op doesn't have a byte code representation, and its conversion
to bytecode kind of assumes that it is only used in a certain way. The
current lowering is also broken and seemingly untested.
* Given that this is a different operation, it gives off the assumption
that it can be used multiple times, or that after the first use
the value contains the inferred types. This isn't the case though,
the resultant type range can never actually be used as a type range.
This commit refactors the representation by removing the discrete
InferredTypesOp, and instead adds a UnitAttr to
pdl_interp.CreateOperation that signals when the created operations
should infer their types. This leads to a much much cleaner abstraction,
a more optimal bytecode lowering, and also allows for better error
handling and diagnostics when a created operation doesn't actually
support type inferrence.
Differential Revision: https://reviews.llvm.org/D124587
This commit refactors the expected form of native constraint and rewrite
functions, and greatly reduces the necessary user complexity required when
defining a native function. Namely, this commit adds in automatic processing
of the necessary PDLValue glue code, and allows for users to define
constraint/rewrite functions using the C++ types that they actually want to
use.
As an example, lets see a simple example rewrite defined today:
```
static void rewriteFn(PatternRewriter &rewriter, PDLResultList &results,
ArrayRef<PDLValue> args) {
ValueRange operandValues = args[0].cast<ValueRange>();
TypeRange typeValues = args[1].cast<TypeRange>();
...
// Create an operation at some point and pass it back to PDL.
Operation *op = rewriter.create<SomeOp>(...);
results.push_back(op);
}
```
After this commit, that same rewrite could be defined as:
```
static Operation *rewriteFn(PatternRewriter &rewriter ValueRange operandValues,
TypeRange typeValues) {
...
// Create an operation at some point and pass it back to PDL.
return rewriter.create<SomeOp>(...);
}
```
Differential Revision: https://reviews.llvm.org/D122086
This provides a way to create an operation without manipulating
OperationState directly. This is useful for creating unregistered ops.
Reviewed By: rriddle, mehdi_amini
Differential Revision: https://reviews.llvm.org/D120787
This support has never really worked well, and is incredibly clunky to
use (it effectively creates two argument APIs), and clunky to generate (it isn't
clear how we should actually expose this from PDL frontends). Treating these
as just attribute arguments is much much cleaner in every aspect of the stack.
If we need to optimize lots of constant parameters, it would be better to
investigate internal representation optimizations (e.g. batch attribute creation),
that do not affect the user (we want a clean external API).
Differential Revision: https://reviews.llvm.org/D121569
Defining our own function operation allows for the PDL interpreter
to be more self contained, and also removes any dependency on FuncOp;
which is moving out of the Builtin dialect.
Differential Revision: https://reviews.llvm.org/D121253
This diff adds an integration test to multi-root PDL matching. It consists of two subtests:
1) A 1-layer perceptron with split forward / backward operations.
2) A 2-layer perceptron with fused forward / backward operations.
These tests use a collection of hand-written patterns and TensorFlow operations to be matched. The first test has a DAG / SSA dominant resulting match; the second does not and is therefore stored in a graph region.
This diff also includes two bug fixes:
1) Mark the pdl_interp dialect as a dependent in the TestPDLByteCodePass. This is needed, because we create ops from that dialect as a part of the PDL-to-PDLInterp lowering.
2) Fix of the starting index in the liveness range for the ForEach operations (bug exposed by the integration test).
Reviewed By: Mogball
Differential Revision: https://reviews.llvm.org/D116082
This is a small diff that splits out the debug output for PDL bytecode. When running bytecode with debug output on, it is useful to know the line numbers where the PDLIntepr operations are performed. Usually, these are in a single MLIR file, so it's sufficient to print out the line number rather than the entire location (which tends to be quite verbose). This debug output is gated by `LLVM_DEBUG` rather than `#ifndef NDEBUG` to make it easier to test.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D114061
This is commit 2 of 4 for the multi-root matching in PDL, discussed in https://llvm.discourse.group/t/rfc-multi-root-pdl-patterns-for-kernel-matching/4148 (topic flagged for review).
This commit implements the features needed for the execution of the new operations pdl_interp.get_accepting_ops, pdl_interp.choose_op:
1. The implementation of the generation and execution of the two ops.
2. The addition of Stack of bytecode positions within the ByteCodeExecutor. This is needed because in pdl_interp.choose_op, we iterate over the values returned by pdl_interp.get_accepting_ops until we reach finalize. When we reach finalize, we need to return back to the position marked in the stack.
3. The functionality to extend the lifetime of values that cross the nondeterministic choice. The existing bytecode generator allocates the values to memory positions by representing the liveness of values as a collection of disjoint intervals over the matcher positions. This is akin to register allocation, and substantially reduces the footprint of the bytecode executor. However, because with iterative operation pdl_interp.choose_op, execution "returns" back, so any values whose original liveness cross the nondeterminstic choice must have their lifetime executed until finalize.
Testing: pdl-bytecode.mlir test
Reviewed By: rriddle, Mogball
Differential Revision: https://reviews.llvm.org/D108547
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
SymbolRefAttr is fundamentally a base string plus a sequence
of nested references. Instead of storing the string data as
a copies StringRef, store it as an already-uniqued StringAttr.
This makes a lot of things simpler and more efficient because:
1) references to the symbol are already stored as StringAttr's:
there is no need to copy the string data into MLIRContext
multiple times.
2) This allows pointer comparisons instead of string
comparisons (or redundant uniquing) within SymbolTable.cpp.
3) This allows SymbolTable to hold a DenseMap instead of a
StringMap (which again copies the string data and slows
lookup).
This is a moderately invasive patch, so I kept a lot of
compatibility APIs around. It would be nice to explore changing
getName() to return a StringAttr for example (right now you have
to use getNameAttr()), and eliminate things like the StringRef
version of getSymbol.
Differential Revision: https://reviews.llvm.org/D108899
This revision allows for attaching "debug labels" to patterns, and provides to FrozenRewritePatternSet for filtering patterns based on these labels (in addition to the debug name of the pattern). This will greatly simplify the ability to write tests targeted towards specific patterns (in cases where many patterns may interact), will also simplify debugging pattern application by observing how application changes when enabling/disabling specific patterns.
To enable better reuse of pattern rewrite options between passes, this revision also adds a new PassUtil.td file to the Rewrite/ library that will allow for passes to easily hook into a common interface for pattern debugging. Two options are used to seed this utility, `disable-patterns` and `enable-patterns`, which are used to enable the filtering behavior indicated above.
Differential Revision: https://reviews.llvm.org/D102441
Motivation: we have passes with lot of rewrites and when one one them segfaults or asserts, it is very hard to find waht exactly pattern failed without debug info.
Differential Revision: https://reviews.llvm.org/D101443
Like `print-ir-after-all` and `-before-all`, this allows to inspect IR for
debug purposes. While the former allow to inspect only between passes, this
change allows to follow the rewrites that happen within passes.
Differential Revision: https://reviews.llvm.org/D100940
To match an interface or trait, users currently have to use the `MatchAny` tag. This tag can be quite problematic for compile time for things like the canonicalizer, as the `MatchAny` patterns may get applied to *every* operation. This revision adds better support by bucketing interface/trait patterns based on which registered operations have them registered. This means that moving forward we will only attempt to match these patterns to operations that have this interface registered. Two simplify defining patterns that match traits and interfaces, two new utility classes have been added: OpTraitRewritePattern and OpInterfaceRewritePattern.
Differential Revision: https://reviews.llvm.org/D98986
This nicely aligns the naming with RewritePatternSet. This type isn't
as widely used, but we keep a using declaration in to help with
downstream consumption of this change.
Differential Revision: https://reviews.llvm.org/D99131
This doesn't change APIs, this just cleans up the many in-tree uses of these
names to use the new preferred names. We'll keep the old names around for a
couple weeks to help transitions.
Differential Revision: https://reviews.llvm.org/D99127
Supporting ranges in the byte code requires additional complexity, given that a range can't be easily representable as an opaque void *, as is possible with the existing bytecode value types (Attribute, Type, Value, etc.). To enable representing a range with void *, an auxillary storage is used for the actual range itself, with the pointer being passed around in the normal byte code memory. For type ranges, a TypeRange is stored. For value ranges, a ValueRange is stored. The above problem represents a majority of the complexity involved in this revision, the rest is adapting/adding byte code operations to support the changes made to the PDL interpreter in the parent revision.
After this revision, PDL will have initial end-to-end support for variadic operands/results.
Differential Revision: https://reviews.llvm.org/D95723
This revision extends the PDL Interpreter dialect to add support for variadic operands and results, with ranges of these values represented via the recently added !pdl.range type. To support this extension, three new operations have been added that closely match the single variant:
* pdl_interp.check_types : Compare a range of types with a known range.
* pdl_interp.create_types : Create a constant range of types.
* pdl_interp.get_operands : Get a range of operands from an operation.
* pdl_interp.get_results : Get a range of results from an operation.
* pdl_interp.switch_types : Switch on a range of types.
This revision handles adding support in the interpreter dialect and the conversion from PDL to PDLInterp. Support for variadic operands and results in the bytecode will be added in a followup revision.
Differential Revision: https://reviews.llvm.org/D95722
This has a numerous amount of benefits, given the overly clunky nature of CreateNativeOp:
* Users can now call into arbitrary rewrite functions from inside of PDL, allowing for more natural interleaving of PDL/C++ and enabling for more of the pattern to be in PDL.
* Removes the need for an additional set of C++ functions/registry/etc. The new ApplyNativeRewriteOp will use the same PDLRewriteFunction as the existing RewriteOp. This reduces the API surface area exposed to users.
This revision also introduces a new PDLResultList class. This class is used to provide results of native rewrite functions back to PDL. We introduce a new class instead of using a SmallVector to simplify the work necessary for variadics, given that ranges will require some changes to the structure of PDLValue.
Differential Revision: https://reviews.llvm.org/D95720
This makes the implementation of each bytecode operation much easier to reason about, and lets the compiler decide which implementations are beneficial to inline into the main switch.
Differential Revision: https://reviews.llvm.org/D95716
This will allow for caching pattern lists across multiple pass instances, such as when multithreading. This is an extremely important invariant for PDL patterns, which are compiled at runtime when the FrozenRewritePatternList is built.
Differential Revision: https://reviews.llvm.org/D93146
The definitions of ModuleOp and FuncOp are now within BuiltinOps.h, making the individual files obsolete.
Differential Revision: https://reviews.llvm.org/D92622
PDL patterns are now supported via a new `PDLPatternModule` class. This class contains a ModuleOp with the pdl::PatternOp operations representing the patterns, as well as a collection of registered C++ functions for native constraints/creations/rewrites/etc. that may be invoked via the pdl patterns. Instances of this class are added to an OwningRewritePatternList in the same fashion as C++ RewritePatterns, i.e. via the `insert` method.
The PDL bytecode is an in-memory representation of the PDL interpreter dialect that can be efficiently interpreted/executed. The representation of the bytecode boils down to a code array(for opcodes/memory locations/etc) and a memory buffer(for storing attributes/operations/values/any other data necessary). The bytecode operations are effectively a 1-1 mapping to the PDLInterp dialect operations, with a few exceptions in cases where the in-memory representation of the bytecode can be more efficient than the MLIR representation. For example, a generic `AreEqual` bytecode op can be used to represent AreEqualOp, CheckAttributeOp, and CheckTypeOp.
The execution of the bytecode is split into two phases: matching and rewriting. When matching, all of the matched patterns are collected to avoid the overhead of re-running parts of the matcher. These matched patterns are then considered alongside the native C++ patterns, which rewrite immediately in-place via `RewritePattern::matchAndRewrite`, for the given root operation. When a PDL pattern is matched and has the highest benefit, it is passed back to the bytecode to execute its rewriter.
Differential Revision: https://reviews.llvm.org/D89107
This class represents a rewrite pattern list that has been frozen, and thus immutable. This replaces the uses of OwningRewritePatternList in pattern driver related API, such as dialect conversion. When PDL becomes more prevalent, this API will allow for optimizing a set of patterns once without the need to do this per run of a pass.
Differential Revision: https://reviews.llvm.org/D89104
There are several pieces of pattern rewriting infra in IR/ that really shouldn't be there. This revision moves those pieces to a better location such that they are easier to evolve in the future(e.g. with PDL). More concretely this revision does the following:
* Create a Transforms/GreedyPatternRewriteDriver.h and move the apply*andFold methods there.
The definitions for these methods are already in Transforms/ so it doesn't make sense for the declarations to be in IR.
* Create a new lib/Rewrite library and move PatternApplicator there.
This new library will be focused on applying rewrites, and will also include compiling rewrites with PDL.
Differential Revision: https://reviews.llvm.org/D89103