If a transformation should be a canonicalization is an orthogonal
question to if a transformation should be implemented as a
`RewritePattern` or a `fold` method. The later is an implementation
detail.
This patch adds a suggestion to always implement a canonicalization as a
`fold` pattern if possible, as they are a restricted subset of a
`RewritePattern`.
This has been a common source of confusion, as to when to implement a
canonicalization as a fold method or a RewritePattern.
The vast majority of rewrite / conversion patterns uses a combined
`matchAndRewrite` instead of separate `match` and `rewrite` functions.
This PR optimizes the code base for the most common case where users
implement a combined `matchAndRewrite`. There are no longer any `match`
and `rewrite` functions in `RewritePattern`, `ConversionPattern` and
their derived classes. Instead, there is a `SplitMatchAndRewriteImpl`
class that implements `matchAndRewrite` in terms of `match` and
`rewrite`.
Details:
* The `RewritePattern` and `ConversionPattern` classes are simpler
(fewer functions). Especially the `ConversionPattern` class, which now
has 5 fewer functions. (There were various `rewrite` overloads to
account for 1:1 / 1:N patterns.)
* There is a new class `SplitMatchAndRewriteImpl` that derives from
`RewritePattern` / `OpRewritePatern` / ..., along with a type alias
`RewritePattern::SplitMatchAndRewrite` for convenience.
* Fewer `llvm_unreachable` are needed throughout the code base. Instead,
we can use pure virtual functions. (In cases where users previously had
to implement `rewrite` or `matchAndRewrite`, etc.)
* This PR may also improve the number of [`-Woverload-virtual`
warnings](https://discourse.llvm.org/t/matchandrewrite-hiding-virtual-functions/84933)
that are produced by GCC. (To be confirmed...)
Note for LLVM integration: Patterns with separate `match` / `rewrite`
implementations, must derive from `X::SplitMatchAndRewrite` instead of
`X`.
---------
Co-authored-by: River Riddle <riddleriver@gmail.com>
This commit adds builders of the form
```
static void build(..., [TypeRange resultTypes],
ValueRange operands, const Properties &properties,
ArrayRef<NamedAttribute> discardableAttributes = {},
[unsigned numRegions]);
```
to go alongside the existing
result/operands/[inherent + discardable attribute list] collective
builders.
This change is intended to support a refactor to the declarative rewrite
engine to make it populate the `Properties` struct instead of creating a
`DictionaryAttr`, thus enabling rewrite rules to handle non-`Attribute`
properties.
More generally, this means that generic code that would previously call
`getAttrs()` to blend together inherent and discardable attributes can
now use `getProperties()` and `getDiscardableAttrs()` separately, thus
removing the need to serialize everything into a temporary
`DictionaryAttr`.
This PR https://github.com/llvm/llvm-project/pull/123902 broke python
bindings for `tensor.pack`/`unpack`. This PR fixes that. It also
1. adds convenience wrappers for pack/unpack
2. cleans up matmul-like ops in the linalg bindings
3. fixes linalg docs missing pack/unpack
The `-buffer-deallocation` pass is not compatible with One-Shot
Bufferize and has been replaced with the Ownership-based Buffer
Deallocation pass about 1.5 years ago. To clean up the code base, this
commit removes the deprecated `buffer-deallocation` pass. All uses of
this deprecated pass within MLIR have already been migrated.
Note for LLVM integration: If you depend on this pass, migrate to the
Ownership-based Buffer Deallocation pass or copy the pass to your
codebase. For details, see
https://discourse.llvm.org/t/psa-bufferization-new-buffer-deallocation-pipeline/73375.
Toy tutorial [chapter 4](https://mlir.llvm.org/docs/Tutorials/Toy/Ch-4/)
contains many discrepancies between snippets and code in `example`
directory.
This is a fix for the documentation.
This patch shares core interface methods dealing with argument and
result attributes from CallableOpInterface with the CallOpInterface and
makes them mandatory to gives more consistent guarantees about concrete
operations using these interfaces.
This allows adding argument attributes on call like operations, which is
sometimes required to get proper ABI, like with llvm.call (and llvm.invoke).
The patch adds optional `arg_attrs` and `res_attrs` attributes to operations using
these interfaces that did not have that already.
They can then re-use the common "rich function signature"
printing/parsing helpers if they want (for the LLVM dialect, this is
done in the next patch).
Part of RFC: https://discourse.llvm.org/t/mlir-rfc-adding-argument-and-result-attributes-to-llvm-call/84107
With the removal of mlir-vulkan-runner (as part of #73457) in
e7e3c45bc7, mlir-cpu-runner is now the
only runner for all CPU and GPU targets, and the "cpu" name has been
misleading for some time already. This commit renames it to mlir-runner.
This patch adds the `host_eval` clause to the `omp.target` operation.
Additionally, it updates its op verifier to make sure all uses of block
arguments defined by this clause fall within one of the few cases where
they are allowed.
MLIR to LLVM IR translation fails on translation of this clause with a
not-yet-implemented error.
This is part of
https://discourse.llvm.org/t/rfc-introduce-opasm-type-attr-interface-for-pretty-print-in-asmprinter/83792.
Verbose printing of commonly used type/attribute that is long could
severely reduce the readablity of the resulting assembly, and it has
been asked several times in the LLVM discourse how to generate alias.
Cc @ftynse
### Discussion
* I am not sure where to put the markdown, so I put it in `mlir/docs/`.
* Documentation on `OpAsmOpInterface` (controlling
`AsmResultName`/`BlockArgName`/etc) could also be added in this
markdown, so I used the title `Customizing AsmPrinter Behavior` and let
further PR to update the content.
OpenACC data clause operations previously required that the variable
operand implemented PointerLikeType interface. This was a reasonable
constraint because the dialects currently mixed with `acc` do use
pointers to represent variables. However, this forces the "pointer"
abstraction to be exposed too early and some cases are not cleanly
representable through this approach (more specifically FIR's `fix.box`
abstraction).
Thus, relax this by allowing a variable to be a type which implements
either `PointerLikeType` interface or `MappableType` interface.
This commit updates the internal `ConversionValueMapping` data structure
in the dialect conversion driver to support 1:N replacements. This is
the last major commit for adding 1:N support to the dialect conversion
driver.
Since #116470, the infrastructure already supports 1:N replacements. But
the `ConversionValueMapping` still stored 1:1 value mappings. To that
end, the driver inserted temporary argument materializations (converting
N SSA values into 1 value). This is no longer the case. Argument
materializations are now entirely gone. (They will be deleted from the
type converter after some time, when we delete the old 1:N dialect
conversion driver.)
Note for LLVM integration: Replace all occurrences of
`addArgumentMaterialization` (except for 1:N dialect conversion passes)
with `addSourceMaterialization`.
---------
Co-authored-by: Markus Böck <markus.boeck02@gmail.com>
`TargetLLVMIR` documentation introduced the C-compatible wrapper
function for a MLIR function and ways to generate it, but did not
demonstrate the corresponding C function signature for them.
The C function signature is not obvious, in that
* `MemrefDescriptor` should be passed as _pointer_.
+ For example, MLIR function could return a new Descriptor, so pointer
is a must.
+ Surprisingly, directly pass the struct, by C convention, is also a
pointer so some function will work, but that is implicit and
error-prone.
* for `@foo() -> memref<>`, the return type becomes the first argument
in `_mlir_ciface_foo(%arg0: !llvm.ptr)`.
+ This is described in
f70ab7d909/mlir/lib/Conversion/FuncToLLVM/FuncToLLVM.cpp (L110-L167)
Especially by code `size_t argOffset = resultStructType ? 1 : 0;` saying
the actual argument starts at 1 when result is a struct (memref)
Users using the wrong signature will get incorrect results. LLVM
discourse has some example of it
*
https://discourse.llvm.org/t/how-to-compile-and-link-with-other-c-c-programs/4835/10
*
https://discourse.llvm.org/t/segmentation-fault-on-memref-store/80286/3
* https://discourse.llvm.org/t/memref-store-storing-a-memref-load/80307
Cc @ftynse for relevent commit history. Cc @charitha22 and @Wheest from
discourse post.
Since the property system isn't currently in heavy use, it's probably
the right time to fix a choice I made when expanding ODS property
support.
Specifically, most of the property subclasses, like OptionalProperty or
IntProperty, wrote out the word "Property" in full. The corresponding
classes in the Attribute hierarchy uses the short-form "Attr" in those
cases, as in OptionalAttr or DefaultValuedAttr.
This commit changes all those uses of "Property" to "Prop" in order to
prevent excessively verbose tablegen files that needlessly repeat the
full name of a core concept that can be abbreviated.
So, this commit renames all the FooProperty classes to FooProp, and
keeps the existing names as alias with a Deprecated<> on them to warn
people.
In addition, this commit updates the documentation around properties to
mention the constraint support.
The greedy rewriter is used in many different flows and it has a lot of
convenience (work list management, debugging actions, tracing, etc). But
it combines two kinds of greedy behavior 1) how ops are matched, 2)
folding wherever it can.
These are independent forms of greedy and leads to inefficiency. E.g.,
cases where one need to create different phases in lowering and is
required to applying patterns in specific order split across different
passes. Using the driver one ends up needlessly retrying folding/having
multiple rounds of folding attempts, where one final run would have
sufficed.
Of course folks can locally avoid this behavior by just building their
own, but this is also a common requested feature that folks keep on
working around locally in suboptimal ways.
For downstream users, there should be no behavioral change. Updating
from the deprecated should just be a find and replace (e.g., `find ./
-type f -exec sed -i
's|applyPatternsAndFoldGreedily|applyPatternsGreedily|g' {} \;` variety)
as the API arguments hasn't changed between the two.
This PR fixes typos within documentation in various files.
Most changes are trivial. The one interesting change is the
documentation for `custom<X>` in `assemblyFormat` that used the wrong
return type. The return type from the `parseX` function should be
`ParseResult` rather than `LogicalResult`. The `ParseResult` type is
necessary due to tablegen generating code like the following within an
Op `parse()` function:
```
auto odsResult = parseInferredArrayType(parser, elementsTypes, elementsOperands, resultRawTypes[0]);
if (odsResult) return ::mlir::failure();
```
This will fail to compile if `parseInferredArrayType()` returns
`LogicalResult`. See also `parsePrettyLLVMType()` in LLVMTypes.h,
`parseSingleBlockRegion()` in IRDL.cpp, `parseDynamicIndexList()` in
ViewLikeInterface.cpp, etc.
This PR adds an `AsmPrinter` option `-mlir-use-nameloc-as-prefix` which
uses trailing `NameLoc`s, if the source IR provides them, as prefixes
when printing SSA IDs.
This PR allows out-of-tree dialects to write Python dialect modules
using nanobind instead of pybind11.
It may make sense to migrate in-tree dialects and some of the ODS Python
infrastructure to nanobind, but that is a topic for a future change.
This PR makes the following changes:
* adds nanobind to the CMake and Bazel build systems. We also add
robin_map to the Bazel build, which is a dependency of nanobind.
* adds a PYTHON_BINDING_LIBRARY option to various CMake functions, such
as declare_mlir_python_extension, allowing users to select a Python
binding library.
* creates a fork of mlir/include/mlir/Bindings/Python/PybindAdaptors.h
named NanobindAdaptors.h. This plays the same role, using nanobind
instead of pybind11.
* splits CollectDiagnosticsToStringScope out of PybindAdaptors.h and
into a new header mlir/include/mlir/Bindings/Python/Diagnostics.h, since
it is code that is no way related to pybind11 or for that matter,
Python.
* changed the standalone Python extension example to have both pybind11
and nanobind variants.
* changed mlir/python/mlir/dialects/python_test.py to have both pybind11
and nanobind variants.
Notes:
* A slightly unfortunate thing that I needed to do in the CMake
integration was to use FindPython in addition to FindPython3, since
nanobind's CMake integration expects the Python_ names for variables.
Perhaps there's a better way to do this.
The terms "legal type" and "illegal type" are ambiguous when talking
about materializations. E.g., for target materializations we do not
necessarily convert from illegal to legal types. We convert from the
most recently mapped value to the type that was produced by converting
the original type.
---------
Co-authored-by: Markus Böck <markus.boeck02@gmail.com>
As described in issue llvm/llvm-project#91518, a previous PR
llvm/llvm-project#78484 introduced the `defaultMemorySpaceFn` into
bufferization options, allowing one to inform OneShotBufferize that it
should use a specified function to derive the memory space attribute
from the encoding attribute attached to tensor types.
However, introducing this feature exposed unhandled edge cases,
examples of which are introduced by this change in the new test under
`test/Dialect/Bufferization/Transforms/one-shot-bufferize-encodings.mlir`.
Fixing the inconsistencies introduced by `defaultMemorySpaceFn` is
pretty simple. This change:
- Updates the `bufferization.to_memref` and `bufferization.to_tensor`
operations to explicitly include operand and destination types,
whereas previously they relied on type inference to deduce the
tensor types. Since the type inference cannot recover the correct
tensor encoding/memory space, the operand and result types must be
explicitly included. This is a small assembly format change, but it
touches a large number of test files.
- Makes minor updates to other bufferization functions to handle the
changes in building the above ops.
- Updates bufferization of `tensor.from_elements` to handle memory
space.
Integration/upgrade guide:
In downstream projects, if you have tests or MLIR files that explicitly
use
`bufferization.to_tensor` or `bufferization.to_memref`, then update
them to the new assembly format as follows:
```
%1 = bufferization.to_memref %0 : memref<10xf32>
%2 = bufferization.to_tensor %1 : memref<10xf32>
```
becomes
```
%1 = bufferization.to_memref %0 : tensor<10xf32> to memref<10xf32>
%2 = bufferization.to_tensor %0 : memref<10xf32> to tensor<10xf32>
```
The dialect conversion-based bufferization passes have been migrated to
One-Shot Bufferize about two years ago. To clean up the code base, this
commit removes the `func-bufferize` pass, one of the few remaining parts
of the old infrastructure. Most bufferization passes have already been
removed.
Note for LLVM integration: If you depend on this pass, migrate to
One-Shot Bufferize or copy the pass to your codebase.
This commit builds on and completes the work done in
9f6c632ecd to eliminate the need for a
separate mlir-spirv-cpu-runner binary. Since the MLIR processing is
already done outside this runner, the only real difference between it
and the mlir-cpu-runner is the final linking step between the nested
LLVM IR modules. By moving this step into mlir-cpu-runner behind a new
command-line flag (`--link-nested-modules`), this commit is able to
completely remove the runner component of the mlir-spirv-cpu-runner.
The runtime libraries and the tests are moved and renamed to fit into
the Execution Engine and Integration tests, following the model of the
similar migration done for the CUDA Runner in D97463.
This is intended as a fast pattern rewrite driver for the cases when a
simple walk gets the job done but we would still want to implement it in
terms of rewrite patterns (that can be used with the greedy pattern
rewrite driver downstream).
The new driver is inspired by the discussion in
https://github.com/llvm/llvm-project/pull/112454 and the LLVM Dev
presentation from @matthias-springer earlier this week.
This limitation comes with some limitations:
* It does not repeat until a fixpoint or revisit ops modified in place
or newly created ops. In general, it only walks forward (in the
post-order).
* `matchAndRewrite` can only erase the matched op or its descendants.
This is verified under expensive checks.
* It does not perform folding / DCE.
We could probably relax some of these in the future without sacrificing
too much performance.
The dialect conversion-based bufferization passes have been migrated to
One-Shot Bufferize about two years ago. To clean up the code base, this
commit removes the `scf-bufferize` pass, one of the few remaining parts
of the old infrastructure. Most bufferization passes have already been
removed.
Note for LLVM integration: If you depend on this pass, migrate to
One-Shot Bufferize or copy the pass to your codebase.
This patch simplifies the representation of OpenMP loop wrapper
operations by introducing the `NoTerminator` trait and updating
accordingly the verifier for the `LoopWrapperInterface`.
Since loop wrappers are already limited to having exactly one region
containing exactly one block, and this block can only hold a single
`omp.loop_nest` or loop wrapper and an `omp.terminator` that does not
return any values, it makes sense to simplify the representation of loop
wrappers by removing the terminator.
There is an extensive list of Lit tests that needed updating to remove
the `omp.terminator`s adding some noise to this patch, but actual
changes are limited to the definition of the `omp.wsloop`, `omp.simd`,
`omp.distribute` and `omp.taskloop` loop wrapper ops, Flang lowering for
those, `LoopWrapperInterface::verifyImpl()`, SCF to OpenMP conversion
and OpenMP dialect documentation.
Initial commit of a tool to help in textual rewrites of .mlir files.
This tool builds of of AsmParserState and is rather simple. Took some
inspiration from when I used clang's AST rewrites where I'd often treat
it as a "localizing" regex applicator in fallback cases, and started
with that as functionality. There though, one does have access to the
lower level info than here, but still a step up over sed over entire
file.
This aims to be helpful (e.g., rewrite syntax including best effort
inside comments) rather than bulletproof tool. It may even be better
suited under utils than tools. And most of the rewrites would be rather
short lived and might never make it upstream (while the helpers of those
rewrites may for future rewrites).
The layering at the moment is not ideal as it is reusing the
RewriteBuffer class from clang's rewrite engine. So only optionally
enabling where clang is also enable. There doesn't seem to be anything
clang specific there (the dep does pull in more dependencies than ideal,
but leaving both refactorings).
Additionally started it as a single file to prototype more easily,
planning to refactor later to include and libs for out of file usage.
`https://mlir.llvm.org/docs/OpDefinitions/` has already been moved (as a
broken link now).
Here it's fixed to the form of relative reference
`DefiningDialects/Operations.md` along with other links.