Functions are always callable operations and thus every operation
implementing the `FunctionOpInterface` also implements the
`CallableOpInterface`. The only exception was the FuncOp in the toy
example. To make implementation of the `FunctionOpInterface` easier,
this commit lets `FunctionOpInterface` inherit from
`CallableOpInterface` and merges some of their methods. More precisely,
the `CallableOpInterface` has methods to get the argument and result
attributes and a method to get the result types of the callable region.
These methods are always implemented the same way as their analogues in
`FunctionOpInterface` and thus this commit moves all the argument and
result attribute handling methods to the callable interface as well as
the methods to get the argument and result types. The
`FuntionOpInterface` then does not have to declare them as well, but
just inherits them from the `CallableOpInterface`.
Adding the inheritance relation also required to move the
`FunctionOpInterface` from the IR directory to the Interfaces directory
since IR should not depend on Interfaces.
Reviewed By: jpienaar, springerm
Differential Revision: https://reviews.llvm.org/D157988
The current implementation is not very ergonomic or descriptive: It uses `std::optional<unsigned>` where `std::nullopt` represents the parent op and `unsigned` is the region number.
This doesn't give us any useful methods specific to region control flow and makes the code fragile to changes due to now taking the region number into account.
This patch introduces a new type called `RegionBranchPoint`, replacing all uses of `std::optional<unsigned>` in the interface. It can be implicitly constructed from a region or a `RegionSuccessor`, can be compared with a region to check whether the branch point is branching from the parent, adds `isParent` to check whether we are coming from a parent op and adds `RegionSuccessor::parent` as a descriptive way to indicate branching from the parent.
Differential Revision: https://reviews.llvm.org/D159116
The `RegionBranchOpInterface` had a few fundamental issues caused by the API design of `getSuccessorRegions`.
It always required passing values for the `operands` parameter. This is problematic as the operands parameter actually changes meaning depending on which predecessor `index` is referring to. If coming from a region, you'd have to find a `RegionBranchTerminatorOpInterface` in that region, get its operand count, and then create a `SmallVector` of that size.
This is not only inconvenient, but also error-prone, which has lead to a bug in the implementation of a previously existing `getSuccessorRegions` overload.
Additionally, this made the method dual-use, trying to serve two different use-cases: 1) Trying to determine possible control flow edges between regions and 2) Trying to determine the region being branched to based on constant operands.
This patch fixes these issues by changing the interface methods and adding new ones:
* The `operands` argument of `getSuccessorRegions` has been removed. The method is now only responsible for returning possible control flow edges between regions.
* An optional `getEntrySuccessorRegions` method has been added. This is used to determine which regions are branched to from the parent op based on constant operands of the parent op. By default, it calls `getSuccessorRegions`. This is analogous to `getSuccessorForOperands` from `BranchOpInterface`.
* Add `getSuccessorRegions` to `RegionBranchTerminatorOpInterface`. This is used to get the possible successors of the terminator based on constant operands. By default, it calls the containing `RegionBranchOpInterface`s `getSuccessorRegions` method.
* `getSuccessorEntryOperands` was renamed to `getEntrySuccessorOperands` for consistency.
Differential Revision: https://reviews.llvm.org/D157506
This implication was already done de-facto and there were plenty of users and wrapper functions specifically used to handle the "return-like or RegionBranchTerminatorOpInterface" case. These simply existed due to up until recently missing features in ODS.
With the new capabilities of traits, we can make `ReturnLike` imply `RegionBranchTerminatorOpInterface` and auto generate proper definitions for its methods.
Various occurrences and wrapper methods used for `isa<RegionBranchTerminatorOpInterface>() || hasTrait<ReturnLike>()` have all been removed.
Differential Revision: https://reviews.llvm.org/D157402
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.
Caveats include:
- This clang-tidy script probably has more problems.
- This only touches C++ code, so nothing that is being generated.
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 first patch was created with the following steps. The intention is
to only do automated changes at first, so I waste less time if it's
reverted, and so the first mass change is more clear as an example to
other teams that will need to follow similar steps.
Steps are described per line, as comments are removed by git:
0. Retrieve the change from the following to build clang-tidy with an
additional check:
https://github.com/llvm/llvm-project/compare/main...tpopp:llvm-project:tidy-cast-check
1. Build clang-tidy
2. Run clang-tidy over your entire codebase while disabling all checks
and enabling the one relevant one. Run on all header files also.
3. Delete .inc files that were also modified, so the next build rebuilds
them to a pure state.
4. Some changes have been deleted for the following reasons:
- Some files had a variable also named cast
- Some files had not included a header file that defines the cast
functions
- Some files are definitions of the classes that have the casting
methods, so the code still refers to the method instead of the
function without adding a prefix or removing the method declaration
at the same time.
```
ninja -C $BUILD_DIR clang-tidy
run-clang-tidy -clang-tidy-binary=$BUILD_DIR/bin/clang-tidy -checks='-*,misc-cast-functions'\
-header-filter=mlir/ mlir/* -fix
rm -rf $BUILD_DIR/tools/mlir/**/*.inc
git restore mlir/lib/IR mlir/lib/Dialect/DLTI/DLTI.cpp\
mlir/lib/Dialect/Complex/IR/ComplexDialect.cpp\
mlir/lib/**/IR/\
mlir/lib/Dialect/SparseTensor/Transforms/SparseVectorization.cpp\
mlir/lib/Dialect/Vector/Transforms/LowerVectorMultiReduction.cpp\
mlir/test/lib/Dialect/Test/TestTypes.cpp\
mlir/test/lib/Dialect/Transform/TestTransformDialectExtension.cpp\
mlir/test/lib/Dialect/Test/TestAttributes.cpp\
mlir/unittests/TableGen/EnumsGenTest.cpp\
mlir/test/python/lib/PythonTestCAPI.cpp\
mlir/include/mlir/IR/
```
Differential Revision: https://reviews.llvm.org/D150123
This is part of an effort to migrate from llvm::Optional to
std::optional. This patch changes the way mlir-tblgen generates .inc
files, and modifies tests and documentation appropriately. It is a "no
compromises" patch, and doesn't leave the user with an unpleasant mix of
llvm::Optional and std::optional.
A non-trivial change has been made to ControlFlowInterfaces to split one
constructor into two, relating to a build failure on Windows.
See also: https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
Signed-off-by: Ramkumar Ramachandra <r@artagnon.com>
Differential Revision: https://reviews.llvm.org/D138934
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
This patch takes the first step towards a more principled modeling of undefined behavior in MLIR as discussed in the following discourse threads:
1. https://discourse.llvm.org/t/semantics-modeling-undefined-behavior-and-side-effects/4812
2. https://discourse.llvm.org/t/rfc-mark-tensor-dim-and-memref-dim-as-side-effecting/65729
This patch in particular does the following:
1. Introduces a ConditionallySpeculatable OpInterface that dynamically determines whether an Operation can be speculated.
2. Re-defines `NoSideEffect` to allow undefined behavior, making it necessary but not sufficient for speculation. Also renames it to `NoMemoryEffect`.
3. Makes LICM respect the above semantics.
4. Changes all ops tagged with `NoSideEffect` today to additionally implement ConditionallySpeculatable and mark themselves as always speculatable. This combined trait is named `Pure`. This makes this change NFC.
For out of tree dialects:
1. Replace `NoSideEffect` with `Pure` if the operation does not have any memory effects, undefined behavior or infinite loops.
2. Replace `NoSideEffect` with `NoSideEffect` otherwise.
The next steps in this process are (I'm proposing to do these in upcoming patches):
1. Update operations like `tensor.dim`, `memref.dim`, `scf.for`, `affine.for` to implement a correct hook for `ConditionallySpeculatable`. I'm also happy to update ops in other dialects if the respective dialect owners would like to and can give me some pointers.
2. Update other passes that speculate operations to consult `ConditionallySpeculatable` in addition to `NoMemoryEffect`. I could not find any other than LICM on a quick skim, but I could have missed some.
3. Add some documentation / FAQs detailing the differences between side effects, undefined behavior, speculatabilty.
Reviewed By: rriddle, mehdi_amini
Differential Revision: https://reviews.llvm.org/D135505
Ops that implement `RegionBranchOpInterface` are allowed to indicate that they can branch back to themselves in `getSuccessorRegions`, but there is no API that allows them to specify the forwarded operands. This patch enables that by changing `getSuccessorEntryOperands` to accept `None`.
Fixes#54928
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D127239
This patch revamps the BranchOpInterface a bit and allows a proper implementation of what was previously `getMutableSuccessorOperands` for operations, which internally produce arguments to some of the block arguments. A motivating example for this would be an invoke op with a error handling path:
```
invoke %function(%0)
label ^success ^error(%1 : i32)
^error(%e: !error, %arg0 : i32):
...
```
The advantages of this are that any users of `BranchOpInterface` can still argue over remaining block argument operands (such as `%1` in the example above), as well as make use of the modifying capabilities to add more operands, erase an operand etc.
The way this patch implements that functionality is via a new class called `SuccessorOperands`, which is now returned by `getSuccessorOperands`. It basically contains an `unsigned` denoting how many operator produced operands exist, as well as a `MutableOperandRange`, which are the usual forwarded operands we are used to. The produced operands are assumed to the first few block arguments, followed by the forwarded operands afterwards. The role of `SuccessorOperands` is to provide various utility functions to modify and query the successor arguments from a `BranchOpInterface`.
Differential Revision: https://reviews.llvm.org/D123062
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 CL adds a new RegionBranchTerminatorOpInterface to query information about operands that can be
passed to successor regions. Similar to the BranchOpInterface, it allows to freely define the
involved operands. However, in contrast to the BranchOpInterface, it expects an additional region
number to distinguish between various use cases which might require different operands passed to
different regions.
Moreover, we added new utility functions (namely getMutableRegionBranchSuccessorOperands and
getRegionBranchSuccessorOperands) to query (mutable) operand ranges for operations equiped with the
ReturnLike trait and/or implementing the newly added interface. This simplifies reasoning about
terminators in the scope of the nested regions.
We also adjusted the SCF.ConditionOp to benefit from the newly added capabilities.
Differential Revision: https://reviews.llvm.org/D105018
This allows for checking if a given operation may modify/reference/or both a given value. Right now this API is limited to Value based memory locations, but we should expand this to include attribute based values at some point. This is left for future work because the rest of the AliasAnalysis API also has this restriction.
Differential Revision: https://reviews.llvm.org/D101673
This revision adds a new `AliasAnalysis` class that represents the main alias analysis interface in MLIR. The purpose of this class is not to hold the aliasing logic itself, but to provide an interface into various different alias analysis implementations. As it evolves this should allow for users to plug in specialized alias analysis implementations for their own needs, and have them immediately usable by other analyses and transformations.
This revision also adds an initial simple generic alias, LocalAliasAnalysis, that provides support for performing stateless local alias queries between values. This class is similar in scope to LLVM's BasicAA.
Differential Revision: https://reviews.llvm.org/D92343