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 removes any potential confusion with the `getType` accessors
which correspond to SSA results of an operation, and makes it
clear what the intent is (i.e. to represent the type of the function).
Differential Revision: https://reviews.llvm.org/D121762
During dialect conversion, target materialization is triggered to create
cast-like operations when a type mismatch occurs between the value that
replaces a rewritten operation and the type that another operations expects as
operands processed by the type conversion. First, a dummy cast is inserted to
make sure the pattern application can proceed. The decision to trigger the
user-provided materialization hook is taken later based on the result of the
dummy cast having uses. However, it only has uses if other patterns constructed
new operations using the casted value as operand. If existing (legal)
operations use the replaced value, they may have not been updated to use the
casted value yet. The conversion infra would then delete the dummy cast first,
and then would replace the uses with now-invalid (null in the bast case) value.
When deciding whether to trigger cast materialization, check for liveness the
uses not only of the casted value, but also of all the values that it replaces.
This was discovered in the finalizing bufferize pass that cleans up
mutually-cancelling casts without touching other operations. It is not
impossible that there are other scenarios where the dialect converison infra
could produce invalid operand uses because of dummy casts erased too eagerly.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D119937
This has been a major TODO for a very long time, and is necessary for establishing a proper
dialect-free dependency layering for the Transforms library. Code was moved to effectively
two main locations:
* Affine/
There was quite a bit of affine dialect related code in Transforms/ do to historical reasons
(of a time way into MLIR's past). The following headers were moved to:
Transforms/LoopFusionUtils.h -> Dialect/Affine/LoopFusionUtils.h
Transforms/LoopUtils.h -> Dialect/Affine/LoopUtils.h
Transforms/Utils.h -> Dialect/Affine/Utils.h
The following transforms were also moved:
AffineLoopFusion, AffinePipelineDataTransfer, LoopCoalescing
* SCF/
Only one SCF pass was in Transforms/ (likely accidentally placed here): ParallelLoopCollapsing
The SCF specific utilities in LoopUtils have been moved to SCF/Utils.h
* Misc:
mlir::moveLoopInvariantCode was also moved to LoopLikeInterface.h given
that it is a simple utility defined in terms of LoopLikeOpInterface.
Differential Revision: https://reviews.llvm.org/D117848
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
This commit refactors the FunctionLike trait into an interface (FunctionOpInterface).
FunctionLike as it is today is already a pseudo-interface, with many users checking the
presence of the trait and then manually into functionality implemented in the
function_like_impl namespace. By transitioning to an interface, these accesses are much
cleaner (ideally with no direct calls to the impl namespace outside of the implementation
of the derived function operations, e.g. for parsing/printing utilities).
I've tried to maintain as much compatability with the current state as possible, while
also trying to clean up as much of the cruft as possible. The general migration plan for
current users of FunctionLike is as follows:
* function_like_impl -> function_interface_impl
Realistically most user calls should remove references to functions within this namespace
outside of a vary narrow set (e.g. parsing/printing utilities). Calls to the attribute name
accessors should be migrated to the `FunctionOpInterface::` equivalent, most everything
else should be updated to be driven through an instance of the interface.
* OpTrait::FunctionLike -> FunctionOpInterface
`hasTrait` checks will need to be moved to isa, along with the other various Trait vs
Interface API differences.
* populateFunctionLikeTypeConversionPattern -> populateFunctionOpInterfaceTypeConversionPattern
Fixes#52917
Differential Revision: https://reviews.llvm.org/D117272
This method simply forwards to populateFunctionLikeTypeConversionPattern,
which is more general. This also helps to remove special treatment of FuncOp from
DialectConversion.
Differential Revision: https://reviews.llvm.org/D116624
Fix confusing diagnostic during partial dialect conversion. A failure to
legalize is not the same as an operation being illegal: for eg. an
operation neither explicity marked legal nor explicitly marked illegal
could have been generated and may have failed to legalize further. The
op isn't an illegal one per
https://mlir.llvm.org/docs/DialectConversion/#conversion-target
which is an op that is explicitly marked illegal.
Differential Revision: https://reviews.llvm.org/D116152
Let the user registers their own handler to processing the matching
failure information.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D110896
MLIR supports recursive types but they could not be handled by the conversion
infrastructure directly as it would result in infinite recursion in
`convertType` for elemental types. Support this case by keeping the "call
stack" of nested type conversions in the TypeConverter class and by passing it
as an optional argument to the individual conversion callback. The callback can
then check if a specific type is present on the stack more than once to detect
and handle the recursive case.
This approach is preferred to the alternative approach of having a separate
callback dedicated to handling only the recursive case as the latter was
observed to introduce ~3% time overhead on a 50MB IR file even if it did not
contain recursive types.
This approach is also preferred to keeping a local stack in type converters
that need to handle recursive types as that would compose poorly in case of
out-of-tree or cross-project extensions.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D113579
OperationLegalizer::isIllegal returns false if operation legality wasn't
registered by user and we expect same behaviour when dynamic legality
callback return None, but instead true was returned.
Differential Revision: https://reviews.llvm.org/D113267
Previously we didn't materialize conversions for arguments in certain
cases as the implicit type propagation was being heavily relied on
by many patterns. Now that those patterns have been fixed to
properly handle type conversions, we can drop the special behavior.
Differential Revision: https://reviews.llvm.org/D113233
This patch fixes:
mlir/lib/Transforms/Utils/DialectConversion.cpp:2775:5: error:
default label in switch which covers all enumeration values
[-Werror,-Wcovered-switch-default]
by removing the default case. This way, the compiler should issue a
warning in the future when somebody adds a new enum value without a
corresponding case in the switch statement.
The current implementation invokes materializations
whenever an input operand does not have a mapping for the
desired type, i.e. it requires materialization at the earliest possible
point. This conflicts with goal of dialect conversion (and also the
current documentation) which states that a materialization is only
required if the materialization is supposed to persist after the
conversion process has finished.
This revision refactors this such that whenever a target
materialization "might" be necessary, we insert an
unrealized_conversion_cast to act as a temporary materialization.
This allows for deferring the invocation of the user
materialization hooks until the end of the conversion process,
where we actually have a better sense if it's actually
necessary. This has several benefits:
* In some cases a target materialization hook is no longer
necessary
When performing a full conversion, there are some situations
where a temporary materialization is necessary. Moving forward,
these users won't need to provide any target materializations,
as the temporary materializations do not require the user to
provide materialization hooks.
* getRemappedValue can now handle values that haven't been
converted yet
Before this commit, it wasn't well supported to get the remapped
value of a value that hadn't been converted yet (making it
difficult/impossible to convert multiple operations in many
situations). This commit updates getRemappedValue to properly
handle this case by inserting temporary materializations when
necessary.
Another code-health related benefit is that with this change we
can move a majority of the complexity related to materializations
to the end of the conversion process, instead of handling adhoc
while conversion is happening.
Differential Revision: https://reviews.llvm.org/D111620
* Change callback signature `bool(Operation *)` -> `Optional<bool>(Operation *)`
* addDynamicallyLegalOp add callback to the chain
* If callback returned empty `Optional` next callback in chain will be called
Differential Revision: https://reviews.llvm.org/D110487
This was causing a subsequent assert/crash when a type converter failed to convert a block argument.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D110985
Should reset the operation to original state when canceling the updates.
Reviewed By: rriddle, ftynse
Differential Revision: https://reviews.llvm.org/D110176
The discussion on forum:
https://llvm.discourse.group/t/bug-in-partial-dialect-conversion/4115
The `applyPartialConversion` didn't handle the operations, that were
marked as illegal inside dynamic legality callback.
Instead of reporting error, if such operation was not converted to legal set,
the method just added it to `unconvertedSet` in the same way as unknown operations.
This patch fixes that and handle dynamically illegal operations as well.
The patch includes 2 fixes for existing passes:
* `tensor-bufferize` - explicitly mark `std.return` as legal.
* `convert-parallel-loops-to-gpu` - ugly fix with marking visited operations
to avoid recursive legality checks.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D108505
This is redundant with the callback variant and untested. Also remove
the callback-less methods for adding a dynamically legal op, as they
are no longer useful.
Differential Revision: https://reviews.llvm.org/D106786
* Get rid of Optional<std::function> as std::function already have a null state
* Add private setLegalityCallback function to set legality callback for unknown ops
* Get rid of unknownOpsDynamicallyLegal flag, use unknownLegalityFn state insted. This causes behavior change when user first calls markUnknownOpDynamicallyLegal with callback and then without but I am not sure is the original behavior was really a 'feature', or just oversignt in the original implementation.
Differential Revision: https://reviews.llvm.org/D105496
Fix dialect conversion ConversionPatternRewriter::cancelRootUpdate: the
erasure of operations here from the list of root update was off by one.
Should have been:
```
rootUpdates.erase(rootUpdates.begin() + (rootUpdates.rend() - it - 1));
```
instead of
```
rootUpdates.erase(rootUpdates.begin() + (rootUpdates.rend() - it));
```
or more directly:
```
rootUpdates.erase(it.base() - 1)
```
While on this, add an assertion to improve dev experience when a cancel is
called on an op on which a root update hasn't been started.
Differential Revision: https://reviews.llvm.org/D105397
The current design uses a unique entry for each argument/result attribute, with the name of the entry being something like "arg0". This provides for a somewhat sparse design, but ends up being much more expensive (from a runtime perspective) in-practice. The design requires building a string every time we lookup the dictionary for a specific arg/result, and also requires N attribute lookups when collecting all of the arg/result attribute dictionaries.
This revision restructures the design to instead have an ArrayAttr that contains all of the attribute dictionaries for arguments and another for results. This design reduces the number of attribute name lookups to 1, and allows for O(1) lookup for individual element dictionaries. The major downside is that we can end up with larger memory usage, as the ArrayAttr contains an entry for each element even if that element has no attributes. If the memory usage becomes too problematic, we can experiment with a more sparse structure that still provides a lot of the wins in this revision.
This dropped the compilation time of a somewhat large TensorFlow model from ~650 seconds to ~400 seconds.
Differential Revision: https://reviews.llvm.org/D102035
This patch introduces the neccessary infrastructure changes to implement
cost-modelling for detensoring. In particular, it introduces the
following changes:
- An extension to the dialect conversion framework to selectively
convert sub-set of non-entry BB arguments.
- An extension to branch conversion pattern to selectively convert
sub-set of a branche's operands.
- An interface for detensoring cost-modelling.
- 2 simple implementations of 2 different cost models.
This sets the stage to explose cost-modelling for detessoring in an
easier way. We still need to come up with better cost models.
Reviewed By: silvas
Differential Revision: https://reviews.llvm.org/D99945
`ConversionPatternRewriter::applySignatureConversion` did not have a way
to apply a signature conversion that involved materializations.
Differential Revision: https://reviews.llvm.org/D99782
This allows for the conversion to match `A(B()) -> C()` with a pattern matching
`A` and marking `B` for deletion.
Also add better assertions when an operation is erased while still having uses.
Differential Revision: https://reviews.llvm.org/D99442
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
This updates the codebase to pass the context when creating an instance of
OwningRewritePatternList, and starts removing extraneous MLIRContext
parameters. There are many many more to be removed.
Differential Revision: https://reviews.llvm.org/D99028
The current implementation of Value involves a pointer int pair with several different kinds of owners, i.e. BlockArgumentImpl*, Operation *, TrailingOpResult*. This design arose from the desire to save memory overhead for operations that have a very small number of results (generally 0-2). There are, unfortunately, many problematic aspects of the current implementation that make Values difficult to work with or just inefficient.
Operation result types are stored as a separate array on the Operation. This is very inefficient for many reasons: we use TupleType for multiple results, which can lead to huge amounts of memory usage if multi-result operations change types frequently(they do). It also means that simple methods like Value::getType/Value::setType now require complex logic to get to the desired type.
Value only has one pointer bit free, severely limiting the ability to use it in things like PointerUnion/PointerIntPair. Given that we store the kind of a Value along with the "owner" pointer, we only leave one bit free for users of Value. This creates situations where we end up nesting PointerUnions to be able to use Value in one.
As noted above, most of the methods in Value need to branch on at least 3 different cases which is both inefficient, possibly error prone, and verbose. The current storage of results also creates problems for utilities like ValueRange/TypeRange, which want to efficiently store base pointers to ranges (of which Operation* isn't really useful as one).
This revision greatly simplifies the implementation of Value by the introduction of a new ValueImpl class. This class contains all of the state shared between all of the various derived value classes; i.e. the use list, the type, and the kind. This shared implementation class provides several large benefits:
* Most of the methods on value are now branchless, and often one-liners.
* The "kind" of the value is now stored in ValueImpl instead of Value
This frees up all of Value's pointer bits, allowing for users to take full advantage of PointerUnion/PointerIntPair/etc. It also allows for storing more operation results as "inline", 6 now instead of 2, freeing up 1 word per new inline result.
* Operation result types are now stored in the result, instead of a side array
This drops the size of zero-result operations by 1 word. It also removes the memory crushing use of TupleType for operations results (which could lead up to hundreds of megabytes of "dead" TupleTypes in the context). This also allowed restructured ValueRange, making it simpler and one word smaller.
This revision does come with two conceptual downsides:
* Operation::getResultTypes no longer returns an ArrayRef<Type>
This conceptually makes some usages slower, as the iterator increment is slightly more complex.
* OpResult::getOwner is slightly more expensive, as it now requires a little bit of arithmetic
From profiling, neither of the conceptual downsides have resulted in any perceivable hit to performance. Given the advantages of the new design, most compiles are slightly faster.
Differential Revision: https://reviews.llvm.org/D97804
This patch continues detensorizing implementation by detensoring
internal control flow in functions.
In order to detensorize functions, all the non-entry block's arguments
are detensored and branches between such blocks are properly updated to
reflect the detensored types as well. Function entry block (signature)
is left intact.
This continues work towards handling github/google/iree#1159.
Reviewed By: silvas
Differential Revision: https://reviews.llvm.org/D97148
This also exposed a bug in Dialect loading where it was not correctly identifying identifiers that had the dialect namespace as a prefix.
Differential Revision: https://reviews.llvm.org/D97431
In dialect conversion infrastructure, source materialization applies as part of
the finalization procedure to results of the newly produced operations that
replace previously existing values with values having a different type.
However, such operations may be created to replace operations created in other
patterns. At this point, it is possible that the results of the _original_
operation are still in use and have mismatching types, but the results of the
_intermediate_ operation that performed the type change are not in use leading
to the absence of source materialization. For example,
%0 = dialect.produce : !dialect.A
dialect.use %0 : !dialect.A
can be replaced with
%0 = dialect.other : !dialect.A
%1 = dialect.produce : !dialect.A // replaced, scheduled for removal
dialect.use %1 : !dialect.A
and then with
%0 = dialect.final : !dialect.B
%1 = dialect.other : !dialect.A // replaced, scheduled for removal
%2 = dialect.produce : !dialect.A // replaced, scheduled for removal
dialect.use %2 : !dialect.A
in the same rewriting, but only the %1->%0 replacement is currently considered.
Change the logic in dialect conversion to look up all values that were replaced
by the given value and performing source materialization if any of those values
is still in use with mismatching types. This is performed by computing the
inverse value replacement mapping. This arguably expensive manipulation is
performed only if there were some type-changing replacements. An alternative
could be to consider all replaced operations and not only those that resulted
in type changes, but it would harm pattern-level composability: the pattern
that performed the non-type-changing replacement would have to be made aware of
the type converter in order to call the materialization hook.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D95626
In dialect conversion, signature conversions essentially perform block argument
replacement and are added to the general value remapping. However, the replaced
values were not tracked, so if a signature conversion was rolled back, the
construction of operand lists for the following patterns could have obtained
block arguments from the mapping and give them to the pattern leading to
use-after-free. Keep track of signature conversions similarly to normal block
argument replacement, and erase such replacements from the general mapping when
the conversion is rolled back.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D95688
This extracts the implementation of getType, setType, and getBody from
FunctionSupport.h into the mlir::impl namespace and defines them
generically in FunctionSupport.cpp. This allows them to be used
elsewhere for any FunctionLike ops that use FunctionType for their
type signature.
Using the new helpers, FuncOpSignatureConversion is generalized to
work with all such FunctionLike ops. Convenience helpers are added to
configure the pattern for a given concrete FunctionLike op type.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D95021
This revision adds a new `replaceOpWithIf` hook that replaces uses of an operation that satisfy a given functor. If all uses are replaced, the operation gets erased in a similar manner to `replaceOp`. DialectConversion support will be added in a followup as this requires adjusting how replacements are tracked there.
Differential Revision: https://reviews.llvm.org/D94632
This corrects the last 2 issues caught by tests when causing dialect
conversion rollbacks to occur.
Differential Revision: https://reviews.llvm.org/D94623
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 better matches the rest of the infrastructure, is much simpler, and makes it easier to move these types to being declaratively specified.
Differential Revision: https://reviews.llvm.org/D93432
The current condition implies that the target materialization will be
called even if the type is the new operand type is legal, but slightly
different. For example, if there is a bufferization pattern that changes
memref layout, then target materialization for an illegal type
(TensorType) would be called.
Differential Revision: https://reviews.llvm.org/D93126
The rewrite logic has an optimization to drop a cast operation after
rewriting block arguments if the cast operation has no users. This is
unsafe as there might be a pending rewrite that replaced the cast operation
itself and hence would trigger a second free.
Instead, do not remove the casts and leave it up to a later canonicalization
to do so.
Differential Revision: https://reviews.llvm.org/D92184