13 Commits

Author SHA1 Message Date
ian Bearman
067d2779fc
[MLIR] Setting MemorySpace During Bufferization (#78484)
Collection of changes with the goal of being able to convert `encoding`
to `memorySpace` during bufferization
- new API for encoder to allow implementation to select destination
memory space
- update existing bufferization implementations to support the new
interface
2024-02-08 16:59:37 +01:00
Matthias Springer
2257ebd33a [mlir][arith][bufferize] Fix crash when bufferizing elementwise arith.select
Elementwise arith.select are currently not supported. Emit an error message instead of crashing. This fixes #61707.

Differential Revision: https://reviews.llvm.org/D158617
2023-08-23 17:40:53 +02:00
Matthias Springer
878950b82c [mlir][bufferization] Simplify getBufferType
`getBufferType` computes the bufferized type of an SSA value without bufferizing any IR. This is useful for predicting the bufferized type of iter_args of a loop.

To avoid endless recursion (e.g., in the case of "scf.for", the type of the iter_arg depends on the type of init_arg and the type of the yielded value; the type of the yielded value depends on the type of the iter_arg again), `fixedTypes` was used to fall back to "fixed" type. A simpler way is to maintain an "invocation stack". `getBufferType` implementations can then inspect the invocation stack to detect repetitive computations (typically when computing the bufferized type of a block argument).

Also improve error messages in case of inconsistent memory spaces inside of a loop.

Differential Revision: https://reviews.llvm.org/D158060
2023-08-16 15:02:07 +02:00
Matthias Springer
a02ad6c177 [mlir][bufferization] Generalize getAliasingOpResults to getAliasingValues
This revision is needed to support bufferization of `cf.br`/`cf.cond_br`. It will also be useful for better analysis of loop ops.

This revision generalizes `getAliasingOpResults` to `getAliasingValues`. An OpOperand can now not only alias with OpResults but also with BlockArguments. In the case of `cf.br` (will be added in a later revision): a `cf.br` operand will alias with the corresponding argument of the destination block.

If an op does not implement the `BufferizableOpInterface`, the analysis in conservative. It previously assumed that an OpOperand may alias with each OpResult. It now assumes that an OpOperand may alias with each OpResult and each BlockArgument of the entry block.

Differential Revision: https://reviews.llvm.org/D157957
2023-08-15 15:02:47 +02:00
Matthias Springer
ba745eea40 [mlir][bufferization] Remove cleanup pipeline from bufferization pass
To keep the pass simple, users should apply cleanup passes manually when necessary. In particular, `-cse -canonicalize` are often desireable to fold away self-copies that are created by the bufferization.

This addresses a comment in D120191.

Differential Revision: https://reviews.llvm.org/D155923
2023-07-21 12:11:25 +02:00
Tres Popp
68f58812e3 [mlir] Move casting calls from methods to function calls
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 patch updates all remaining uses of the deprecated functionality in
mlir/. This was done with clang-tidy as described below and further
modifications to GPUBase.td and OpenMPOpsInterfaces.td.

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:
   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.

```
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
```

Differential Revision: https://reviews.llvm.org/D151542
2023-05-26 10:29:55 +02:00
Tres Popp
5550c82189 [mlir] Move casting calls from methods to function calls
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
2023-05-12 11:21:25 +02:00
Maya Amrami
8bb5ca5832 [mlir] Support bufferization of arith.constant to memref.global with memory space
Reviewed By: springerm

Differential Revision: https://reviews.llvm.org/D146381
2023-03-20 17:09:51 +02:00
Matthias Springer
9fa6b3504b [mlir][bufferization] Improve aliasing OpOperand/OpResult property
`getAliasingOpOperands`/`getAliasingOpResults` now encodes OpOperand/OpResult, buffer relation and a degree of certainty. E.g.:
```
// aliasingOpOperands(%r) = {(%t, EQUIV, DEFINITE)}
// aliasingOpResults(%t) = {(%r, EQUIV, DEFINITE)}
%r = tensor.insert %f into %t[%idx] : tensor<?xf32>

// aliasingOpOperands(%r) = {(%t0, EQUIV, MAYBE), (%t1, EQUIV, MAYBE)}
// aliasingOpResults(%t0) = {(%r, EQUIV, MAYBE)}
// aliasingOpResults(%t1) = {(%r, EQUIV, MAYBE)}
%r = arith.select %c, %t0, %t1 : tensor<?xf32>
```

`BufferizableOpInterface::bufferRelation` is removed, as it is now part of `getAliasingOpOperands`/`getAliasingOpResults`.

This change allows for better analysis, in particular wrt. equivalence. This allows additional optimizations and better error checking (which is sometimes overly conservative). Examples:

* EmptyTensorElimination can eliminate `tensor.empty` inside `scf.if` blocks. This requires a modeling of equivalence: It is not a per-OpResult property anymore. Instead, it can be specified for each OpOperand and OpResult. This is important because `tensor.empty` may be eliminated only if all values on the SSA use-def chain to the final consumer (`tensor.insert_slice`) are equivalent.
* The detection of "returning allocs from a block" can be improved. (Addresses a TODO in `assertNoAllocsReturned`.) This allows us to bufferize IR such as "yielding a `tensor.extract_slice` result from an `scf.if` branch", which currently fails to bufferize because the alloc detection is too conservative.
* Better bufferization of loops. Aliases of the iter_arg can be yielded (even if they are not equivalent) without having to realloc and copy the entire buffer on each iteration.

The above-mentioned examples are not yet implemented with this change. This change just improves the BufferizableOpInterface, its implementations and related helper functions, so that better aliasing information is available for each op.

Differential Revision: https://reviews.llvm.org/D142129
2023-02-09 11:35:03 +01:00
Matthias Springer
1ac248e485 [mlir][bufferization][NFC] Rename getAliasingOpOperand/getAliasingOpResult
* `getAliasingOpOperand` => `getAliasingOpOperands`
* `getAliasingOpResult` => `getAliasingOpResults`

Also a few minor code cleanups and better documentation.

Differential Revision: https://reviews.llvm.org/D142979
2023-02-01 10:07:41 +01:00
Matthias Springer
148432ea84 [mlir][bufferization][NFC] Rename BufferRelation::None to BufferRelation::Unknown
The previous name was incorrect. `None` does not mean that there is no buffer relation between two buffers (seems to imply that they do not alias for sure); instead it means that there is no further information available.

Differential Revision: https://reviews.llvm.org/D142870
2023-01-30 11:09:28 +01:00
Lei Zhang
9bb633741a [mlir][bufferization] Support general Attribute as memory space
MemRef has been accepting a general Attribute as memory space for
a long time. This commits updates bufferization side to catch up,
which allows downstream users to plugin customized symbolic memory
space. This also eliminates quite a few `getMemorySpaceAsInt`
calls, which is deprecated.

Reviewed By: springerm

Differential Revision: https://reviews.llvm.org/D138330
2022-11-21 09:40:50 -05:00
Jakub Kuderski
abc362a107 [mlir][arith] Change dialect name from Arithmetic to Arith
Suggested by @lattner in https://discourse.llvm.org/t/rfc-define-precise-arith-semantics/65507/22.

Tested with:
`ninja check-mlir check-mlir-integration check-mlir-mlir-spirv-cpu-runner check-mlir-mlir-vulkan-runner check-mlir-examples`

and `bazel build --config=generic_clang @llvm-project//mlir:all`.

Reviewed By: lattner, Mogball, rriddle, jpienaar, mehdi_amini

Differential Revision: https://reviews.llvm.org/D134762
2022-09-29 11:23:28 -04:00