Transform interfaces are implemented, direction or via extensions, in
libraries belonging to multiple other dialects. Those dialects don't
need to depend on the non-interface part of the transform dialect, which
includes the growing number of ops and transitive dependency footprint.
Split out the interfaces into a separate library. This in turn requires
flipping the dependency from the interface on the dialect that has crept
in because both co-existed in one library. The interface shouldn't
depend on the transform dialect either.
As a consequence of splitting, the capability of the interpreter to
automatically walk the payload IR to identify payload ops of a certain
kind based on the type used for the entry point symbol argument is
disabled. This is a good move by itself as it simplifies the interpreter
logic. This functionality can be trivially replaced by a
`transform.structured.match` operation.
From https://reviews.llvm.org/D153245
This adds support for native PDL (and PDLL) C++ constraints to return
results.
This is useful for situations where a pattern checks for certain
constraints of multiple interdependent attributes and computes a new
attribute value based on them. Currently, for such an example it is
required to escape to C++ during matching to perform the check and after
a successful match again escape to native C++ to perform the computation
during the rewriting part of the pattern. With this work we can do the
computation in C++ during matching and use the result in the rewriting
part of the pattern. Effectively this enables a choice in the trade-off
of memory consumption during matching vs recomputation of values.
This is an example of a situation where this is useful: We have two
operations with certain attributes that have interdependent constraints.
For instance `attr_foo: one_of [0, 2, 4, 8], attr_bar: one_of [0, 2, 4,
8]` and `attr_foo == attr_bar`. The pattern should only match if all
conditions are true. The new operation should be created with a new
attribute which is computed from the two matched attributes e.g.
`attr_baz = attr_foo * attr_bar`. For the check we already escape to
native C++ and have all values at hand so it makes sense to directly
compute the new attribute value as well:
```
Constraint checkAndCompute(attr0: Attr, attr1: Attr) -> Attr;
Pattern example with benefit(1) {
let foo = op<test.foo>() {attr = attr_foo : Attr};
let bar = op<test.bar>(foo) {attr = attr_bar : Attr};
let attr_baz = checkAndCompute(attr_foo, attr_bar);
rewrite bar with {
let baz = op<test.baz> {attr=attr_baz};
replace bar with baz;
};
}
```
To achieve this the following notable changes were necessary:
PDLL:
- Remove check in PDLL parser that prevented native constraints from
returning results
PDL:
- Change PDL definition of pdl.apply_native_constraint to allow variadic
results
PDL_interp:
- Change PDL_interp definition of pdl_interp.apply_constraint to allow
variadic results
PDLToPDLInterp Pass:
The input to the pass is an arbitrary number of PDL patterns. The pass
collects the predicates that are required to match all of the pdl
patterns and establishes an ordering that allows creation of a single
efficient matcher function to match all of them. Values that are matched
and possibly used in the rewriting part of a pattern are represented as
positions. This allows fusion and thus reusing a single position for
multiple matching patterns. Accordingly, we introduce
ConstraintPosition, which records the type and index of the result of
the constraint. The problem is for the corresponding value to be used in
the rewriting part of a pattern it has to be an input to the
pdl_interp.record_match operation, which is generated early during the
pass such that its surrounding block can be referred to by branching
operations. In consequence the value has to be materialized after the
original pdl.apply_native_constraint has been deleted but before we get
the chance to generate the corresponding pdl_interp.apply_constraint
operation. We solve this by emitting a placeholder value when a
ConstraintPosition is evaluated. These placeholder values (due to fusion
there may be multiple for one constraint result) are replaced later when
the actual pdl_interp.apply_constraint operation is created.
Changes since the phabricator review:
- Addressed all comments
- In particular, removed registerConstraintFunctionWithResults and
instead changed registerConstraintFunction so that contraint functions
always have results (empty by default)
- Thus we don't need to reuse `rewriteFunctions` to store constraint
functions with results anymore, and can instead use
`constraintFunctions`
- Perform a stable sort of ConstraintQuestion, so that
ConstraintQuestion appear before other ConstraintQuestion that use their
results.
- Don't create placeholders for pdl_interp::ApplyConstraintOp. Instead
generate the `pdl_interp::ApplyConstraintOp` before generating the
successor block.
- Fixed a test failure in the pdl python bindings
Original code by @martin-luecke
Co-authored-by: martin-luecke <martinpaul.luecke@amd.com>
Introduce a new extension for simple print-debugging of the transform
dialect scripts. The initial version of this extension consists of two
ops that are printing the payload objects associated with transform
dialect values. Similar ops were already available in the test extenion
and several downstream projects, and were extensively used for testing.
Add a new transform operation that creates a new parameter containing the number of payload objects (operations, values or attributes) associated with the argument. This is useful in matching and for debugging purposes. This replaces three ad-hoc operations previously provided by the test extension.
Same as #66369 but for payload values. (#66369 added checks only for
payload operations.)
It was necessary to change the signature of `getPayloadValues` to return
an iterator. This is now similar to payload operations.
Fixes an issue in #66369 where the `LLVM_ENABLE_ABI_BREAKING_CHECKS`
check was inverted.
This change adds a method to modify the ConversionTarget used during
`transform.apply_conversion_patterns` to the
`ConversionPatternDescriptorOpInterface`. This is needed when the TypeConverter
is used to dictate the dynamic legality of operations, as in "structural"
conversion patterns present in, for example, the SCF and func dialects.
As a first use case/test, this change also adds a
`transform.apply_patterns.scf.structural_conversions` operation to the SCF
dialect.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D158672
Fixes a crash when an op, that is mapped to handle that a
`transform.foreach` iterates over, was erased (through the
`TrackingRewriter`). Erasing an op removes it from all mappings and
invalidates iterators. This is already taken care of when an op is
iterating over payload ops in its `apply` method, but not when another
transform op is erasing a tracked payload op.
This transform op applies a dialect conversion to the targeted ops. Its design is similar to `apply_patterns`.
Patterns are specified in the first region of `apply_conversion_patterns`. They must implement the `ConversionPatternDescriptorOpInterface`. Regular rewrite patterns and dialect conversion patterns should not be mixed, so the interface is separate from the `PatternDescriptorOpInterface`.
The type converter is specified as the single op of the second region. It is optional; if no type converter is specified, it is expected that pattern descriptors provide their own type converters. If both the pattern descriptors and the `apply_conversion_patterns` op specify a type converter, the type converter of the pattern descriptor is used.
Differential Revision: https://reviews.llvm.org/D157109
This function allows users to update payload op mappings in cases where such replacements cannot be performed automatically by the rewriter/listener interface.
Differential Revision: https://reviews.llvm.org/D153764
When exiting the scope of a region attached to a transform op, clean up
the handle invalidation checks assocaited with handles defined in this
region. Otherwise, these checks may trigger on the next entry to the
region while there is no incorrect usage.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D153545
Similar to operation handles, merging handles for other types can be useful to
avoid repetition of common transformations across a set of parameters.
For example, forming a list of static values for comparison rather than
comparing the parameters one at a time.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D153240
All `apply` functions now have a `TransformRewriter &` parameter. This rewriter should be used to modify the IR. It has a `TrackingListener` attached and updates the internal handle-payload mappings based on rewrites.
Implementations no longer need to create their own `TrackingListener` and `IRRewriter`. Error checking is integrated into `applyTransform`. Tracking listener errors are reported only for ops with the `ReportTrackingListenerFailuresOpTrait` trait attached, allowing for a gradual migration. Furthermore, errors can be silenced with an op attribute.
Additional API will be added to `TransformRewriter` in subsequent revisions. This revision just adds an "empty" `TransformRewriter` class and updates all `apply` implementations.
Differential Revision: https://reviews.llvm.org/D152427
Use the default TrackingListener. No need to set up a derived listener just for the test case. This revision is in preparation of a future change that adds a TrackingRewriter infrastructure.
Differential Revision: https://reviews.llvm.org/D152446
When looking for replacement ops (`findReplacementOp`) distinguish between "no replacement could be found" and "this op should be dropped from the mapping". The latter case will be utilized in a subsequent revision when a payload op is mapped to a consumed handle.
Differential Revision: https://reviews.llvm.org/D152375
* Remove `transform::PatternRegistry`.
* Add a new op for each currently registered pattern set.
* Change names of vector dialect pattern selector ops, so that they are consistent with the remaining code base.
* Remove redundant `transform.vector.extract_address_computations` op.
Differential Revision: https://reviews.llvm.org/D152249
Patterns should be selected by adding ops that implement `PatternDescriptorOpInterface` to the region of `apply_pattern` ops. Such ops can have operands, allowing for pattern parameterization. The existing way of selecting patterns from the PatternRegistry is deprecated.
Differential Revision: https://reviews.llvm.org/D152167
Add a new transform op that applies patterns to a targeted payload op. Patterns can be registered by transform dialect extensions in a pattern registry.
Differential Revision: https://reviews.llvm.org/D151983
Transform operations may indicate that they may accept and consume
several handles pointing to the same or nested payload entities. The
initial implementation of the expensive-checks mode was simply ignoring
such cases as consuming the second handle would fail the check after the
first handle invalidated it by consuming the same payload. Additional
checks had been added since then, which could now trigger assertions in
the expensive-checks module itself (instead of or in addition to
use-after-free assertions down the road), specifically because the
payload associations for invalidated handles is removed from the state
to enable other kinds of checking.
Rework the handling of transform operations with repeated handles so
use-after-consume is still reported properly if the consumption happened
by a preceding operation, as opposed to the a preceding operand of the
same operation that is still (corretly) ignored if the op requests that.
Depends on: D151560
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D151569
The transform dialect interpreter features the expensive-checks mode
that acts as an embedded sanitizer to track use-after-consume of
transform handles. Its logic is based on the relations between payload
operations, which made it silently ignore empty handles that are
consumed. Also catch and report this case because the remaining code may
hit an assertion on attempting to access a consumed handle (that is
removed from the mapping).
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D151560
The initial bring-up of the Transform dialect relied on PDL to provide
the default handle type (`!pdl.operation`) and the matching capability.
Both are now provided natively by the Transform dialect removing the
reason to have a hard dependency on the PDL dialect and its interpreter.
Move PDL-related transform operations into a separate extension.
This requires us to introduce a dialect state extension mechanism into
the Transform dialect so it no longer needs to know about PDL constraint
functions that may be injected by extensions similarly to operations and
types. This mechanism will be reused to connect pattern application
drivers and the Transform dialect.
This completes the restructuring of the Transform dialect to remove
overrilance on PDL.
Note to downstreams: flow that are using `!pdl.operation` with Transform
dialect operations will now require `transform::PDLExtension` to be
applied to the transform dialect in order to provide the transform
handle type interface for `!pdl.operation`.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D151104
Instead of returning an `ArrayRef<Operation *>`, return at iterator that skips ops that were erased/replaced while iterating over the payload ops.
This fixes an issue in conjuction with TrackingListener, where a tracked op was erased during the iteration. Elements may not be removed from an array while iterating over it; this invalidates the iterator.
When ops are erased/removed via `replacePayloadOp`, they are not immediately removed from the mappings data structure. Instead, they are set to `nullptr`. `nullptr`s are not enumerated by `getPayloadOps`. At the end of each transformation, `nullptr`s are removed from the mapping data structure.
Differential Revision: https://reviews.llvm.org/D149847
The MLIR classes Type/Attribute/Operation/Op/Value support
cast/dyn_cast/isa/dyn_cast_or_null functionality through llvm's doCast
functionality in addition to defining methods with the same name.
This change begins the migration of uses of the method to the
corresponding function call as has been decided as more consistent.
Note that there still exist classes that only define methods directly,
such as AffineExpr, and this does not include work currently to support
a functional cast/isa call.
Context:
* https://mlir.llvm.org/deprecation/ at "Use the free function variants for dyn_cast/cast/isa/…"
* Original discussion at https://discourse.llvm.org/t/preferred-casting-style-going-forward/68443
Implementation:
This follows a previous patch that updated calls
`op.cast<T>()-> cast<T>(op)`. However some cases could not handle an
unprefixed `cast` call due to occurrences of variables named cast, or
occurring inside of class definitions which would resolve to the method.
All C++ files that did not work automatically with `cast<T>()` are
updated here to `llvm::cast` and similar with the intention that they
can be easily updated after the methods are removed through a
find-replace.
See https://github.com/llvm/llvm-project/compare/main...tpopp:llvm-project:tidy-cast-check
for the clang-tidy check that is used and then update printed
occurrences of the function to include `llvm::` before.
One can then run the following:
```
ninja -C $BUILD_DIR clang-tidy
run-clang-tidy -clang-tidy-binary=$BUILD_DIR/bin/clang-tidy -checks='-*,misc-cast-functions'\
-export-fixes /tmp/cast/casts.yaml mlir/*\
-header-filter=mlir/ -fix
rm -rf $BUILD_DIR/tools/mlir/**/*.inc
```
Differential Revision: https://reviews.llvm.org/D150348
Add a set of transform operations into the "structured" extension of the
Transform dialect that allow one to select transformation targets more
specifically than the currently available matching. In particular, add
the mechanism for identifying the producers of operands (input and init
in destination-passing style) and users of results, as well as
mechanisms for reasoning about the shape of the iteration space.
Additionally, add several transform operations to manipulate parameters
that could be useful to implement more advanced selectors. Specifically,
new operations let one produce and compare parameter values to implement
shape-driven transformations.
New operations are placed in separate files to decrease compilation
time. Some relayering of the extension is necessary to avoid repeated
generation of enums.
Depends on D148013
Depends on D148014
Depends on D148015
Reviewed By: chelini
Differential Revision: https://reviews.llvm.org/D148017
Add a new transform op combinator that implements an "if-then-else"
style of mechanism for applying transformations. Its main purpose is to
serve as a higher-level driver when applying multiple transform scripts
to potentially overlapping pieces of the payload IR. This is similar to
how the various rewrite drivers operate in C++, but at a higher level
and with more declarative expressions. This is not intended to replace
existing pattern-based rewrites, but to to drive more complex
transformations that are exposed in the transform dialect and are too
complex to be expressed as simple declarative rewrites.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D148013
This revision adds additional "expensive-checks" checks to the transform dialect that detect the most common cases of:
* Missing `consumesHandle` side effects on transform ops.
* Patterns that remove operations but do not notify the transform dialect.
In essence, these additional checks are looking for dangling pointers to erased payload ops in the transform dialect state and crash the program execution (by dereferencing free'd memory) or triggering an assertion failure. It is recommended to run these extra checks with ASAN. Otherwise, certain failures may not be detected. The ASAN error message can also be used to find the faulty transform op/pattern.
This change also fixes a few faulty transform ops.
Differential Revision: https://reviews.llvm.org/D147447
The initial implementaiton of value handle update when the payload
operation defining the values associated with value handles was being
replaced required the replacement operation to have the same number of
results. This is not strictly necessary. The replacement operation may
have more results, or less results provided that there are no handles to
the results that have no equivalent in the replacement op.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D145254
Introduce support for the third kind of values in the transform dialect:
value handles. Similarly to operation handles, value handles are
pointing to a set of values in the payload IR. This enables
transformation to be targeted at specific values, such as individual
results of a multi-result payload operation without indirecting through
the producing op or block arguments that previously could not be easily
addressed. This is expected to support a broad class of memory-oriented
transformations such as selective bufferization, buffer assignment, and
memory transfer management.
Value handles are functionally similar to operation handles and require
similar implementation logic. The most important change concerns the
handle invalidation mechanism where operation and value handles can
affect each other.
This patch includes two cleanups that make it easier to introduce value
handles:
- `RaggedArray` structure that encapsulates the SmallVector of
ArrayRef backed by flat SmallVector logic, frequently used in the
transform interfaces implementation;
- rewrite the tests that associated payload handles with an integer
value `reinterpret_cast`ed as a pointer, which were a frequent
source of confusion and crashes when adding more debugging
facilities that can inspect the payload.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D143385
Add a verifier checking that if a transform operation consumes a handle
(which is associated with a payload operation being erased or
recreated), it also indicates modification of the payload IR. This
hasn't been consistent in the past because of the "no-aliasing"
assumption where we couldn't have had more than one handle to an
operation, requiring some handle-manipulation operations, such as
`transform.merge_handles` to consume their operands. That assumption has
been liften and it is no longer necessary for these operations to
consume handles and thus make the life harder for the clients.
Additionally, remove TransformEffects.td that uses the ODS mechanism for
indicating side effects that works only for operands and results. It
was being used incorrectly to also indicate effects on the payload IR,
not assocaited with any IR value, and lacked the consume/produce
semantics available via helpers in C++.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D142361
Add a verifier to the TransformOpInterface ensuring that operations
implementing the interface define memory effects on their operands and
results.
Add the missing effects to TileToForeachThreadOp, specifically for
operands that were added at a later version of the op without modifying
`getEffects` accordingly.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D141371
When establishing the correspondence between transform values and
payload operations or parameters, check that the latter are non-null and
report errors. This was previously allowed for exotic cases of partially
successfull transformations with "apply each" trait, but was dangerous.
The "apply each" implementation was reworked to remove the need for this
functionality, so this can now be hardned to avoid null pointer
dereferences.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D141142
Adapt the implementation of TransformEachOpTrait to the existence of
parameter values recently introduced into the transform dialect. In
particular, allow `applyToOne` hooks to return a list containing a mix
of `Operation *` that will be associated with handles and `Attribute`
that will be associated with parameter values by the trait
implementation of the transform interface's `apply` method.
Disentangle the "transposition" of the list of per-payload op partial
results to decrease its overall complexity and detemplatize the code
that doesn't really need templates. This removes the poorly documented
special handling for single-result ops with TransformEachOpTrait that
could have assigned null pointer values to handles.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D140979
Introduce a new kind of values into the transform dialect -- parameter
values. These values have a type implementing the new
`TransformParamTypeInterface` and are associated with lists of
attributes rather than lists of payload operations. This mechanism
allows one to wrap numeric calculations, typically heuristics, into
transform operations separate from those at actually applying the
transformation. For example, tile size computation can be now separated
from tiling itself, and not hardcoded in the transform dialect. This
further improves the separation of concerns between transform choice and
implementation.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D140976
This class adds helper functions similar to `emitError` for the
DiagnosedSilenceableFailure class in both the silenceable and definite
failure cases. These helpers simplify the use of said class and make
tranfsorm op application code idiomatic.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D136072
Introduce a type system for the transform dialect. A transform IR type
captures the expectations of the transform IR on the payload IR
operations that are being transformed, such as being of a certain kind
or implementing an interface that enables the transformation. This
provides stricter checking and better readability of the transform IR
than using the catch-all "handle" type.
This change implements the basic support for a type system amendable to
dialect extensions and adds a drop-in replacement for the unrestricted
"handle" type. The actual switch of transform dialect ops to that type
will happen in a separate commit.
See https://discourse.llvm.org/t/rfc-type-system-for-the-transform-dialect/65702
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D135164
The transform.split_handles op is useful for ensuring a statically known number of operations are
tracked by the source `handle` and to extract them into individual handles
that can be further manipulated in isolation.
In the process of making the op robust wrt to silenceable errors and the suppress mode, issues were
uncovered and fixed.
The main issue was that silenceable errors were short-circuited too early and the payloads were not
set. This resulted in suppressed silenceable errors not propagating correctly.
Fixing the issue triggered a few test failures: silenceable error returns now must properly set the results state.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D135426
Relax the restriction in the transform dialect interpreter utilities
that expected a payload IR op to be assocaited with at most one
transform IR handle value. This was useful during the initial
bootstrapping to avoid use-after-free error equivalents when a payload
IR op could be erased through one of the handles associated with it and
then accessed through another. It was, however, possible to erase an
ancestor of the payload IR operation in question. The expensive-checks
mode of interpretation is able to detect both cases and has proven
sufficiently robust in debugging use-after-free errors.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D134964
Introduce two different failure propagation mode in the Transform
dialect's Sequence operation. These modes specify whether silenceable
errors produced by nested ops are immediately propagated, thus stopping
the sequence, or suppressed. The latter is useful in end-to-end
transform application scenarios where the user cannot correct the
transformation, but it is robust enough to silenceable failures. It
can be combined with the "alternatives" operation. There is
intentionally no default value to avoid favoring one mode over the
other.
Downstreams can update their tests using:
S='s/sequence \(%.*\) {/sequence \1 failures(propagate) {/'
T='s/sequence {/sequence failures(propagate) {/'
git grep -l transform.sequence | xargs sed -i -e "$S"
git grep -l transform.sequence | xargs sed -i -e "$T"
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D131774
In the Transform dialect extensions, provide the separate mechanism to
declare dependent dialects (the dialects the transform IR depends on)
and the generated dialects (the dialects the payload IR may be
transformed into). This allows the Transform dialect clients that are
only constructing the transform IR to avoid loading the dialects
relevant for the payload IR along with the Transform dialect itself,
thus decreasing the build/link time.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D130289
This handle manipulation operation allows one to define a new handle that is
associated with a the same payload IR operations N times, where N can be driven
by the size of payload IR operation list associated with another handle. This
can be seen as a sort of broadcast that can be used to ensure the lists
associated with two handles have equal numbers of payload IR ops as expected by
many pairwise transform operations.
Introduce an additional "expensive" check that guards against consuming a
handle that is assocaited with the same payload IR operation more than once as
this is likely to lead to double-free or other undesired effects.
Depends On D129110
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D129216
This revision revisits the implementation of applyToOne and its handling
of recoverable errors as well as propagation of null handles.
The implementation is simplified to always require passing a vector<Operation*>
in which the results are returned, resulting in less template instantiation magic.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D129185
