As part of the work on transitioning bufferization dialect, ops, and
associated logic to operate on newly added type interfaces (see
00eaff3e9c897c263a879416d0f151d7ca7eeaff), rename the
bufferization.to_memref to highlight the generic nature of the op.
Bufferization process produces buffers while memref is a builtin type
rather than a generic term.
Preserve the current API (to_buffer still produces a memref), however,
as the new type interfaces are not used yet.
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.
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 commit marks the type converter in `populate...` functions as
`const`. This is useful for debugging.
Patterns already take a `const` type converter. However, some
`populate...` functions do not only add new patterns, but also add
additional type conversion rules. That makes it difficult to find the
place where a type conversion was added in the code base. With this
change, all `populate...` functions that only populate pattern now have
a `const` type converter. Programmers can then conclude from the
function signature that these functions do not register any new type
conversion rules.
Also some minor cleanups around the 1:N dialect conversion
infrastructure, which did not always pass the type converter as a
`const` object internally.
Move the documentation of the ownership-based buffer deallocation pass
to a separate file. Also improve the documentation a bit and insert a
figure that explains the `bufferization.dealloc` op (copied from the
tutorial at the LLVM Dev Summit 2023).
Even when `private-function-dynamic-ownership` is set, ownership should
never be passed to the callee. This can lead to double deallocs (#77096)
or use-after-free in the caller because ownership is currently passed
regardless of whether there are any further uses of the buffer in the
caller or not.
Note: This is consistent with the fact that ownership is never passed to
nested regions.
This commit fixes#77096.
I was reading through the very well written Destination-Passing Style
docs. Even though I know not much about compilers, I managed to
understand it pretty well. A few things tripped me up though, which this
PR suggests to rewrite:
1. Write `buffer(%0)` instead of buffer(`%0`). While reading, I first
interpreted the text as "the buffer (%0)", whereas it should be
interpreted as pseudocode for "a function that determines the buffer
applied to %0". Quickly introducing it and moving the backticks around
as this PR does should make this more clear. Also, I verified that MLIR
does not contain any other occurences of `"buffer(<BACKTICK>"`. It does
contain many occurences of `"buffer("` (without the backtick after the
opening bracket), so this PR makes notation a bit more consistent.
2. Quotation marks slowed me down during reading, so I removed them. I
think it's also clear without.
3. The `outs` from `linalg` was suddenly introduced. I've tried to
clarify in as few words as possible that `outs` stands for `outputs` but
suggestions are welcome.
This commit removes the deallocation capabilities of
one-shot-bufferization. One-shot-bufferization should never deallocate
any memrefs as this should be entirely handled by the
ownership-based-buffer-deallocation pass going forward. This means the
`allow-return-allocs` pass option will default to true now,
`create-deallocs` defaults to false and they, as well as the escape
attribute indicating whether a memref escapes the current region, will
be removed. A new `allow-return-allocs-from-loops` option is added as a
temporary workaround for some bufferization limitations.
Add a new Buffer Deallocation pass with the intend to replace the old
one. For now it is added as a separate pass alongside in order to allow
downstream users to migrate over gradually. This new pass has the goal
of inserting fewer clone operations and supporting additional use-cases.
Please refer to the Buffer Deallocation section in the updated
Bufferization.md file for more information on how this new pass works.
This reverts commit 6a91dfedeb956dfa092a6a3f411e8b02f0d5d289.
This caused problems in downstream projects. We are reverting to give
them more time for integration.
This reverts commit 1bebb60a7565e5197d23120528f544b886b4d905.
This caused problems in downstream projects. We are reverting to give
them more time for integration.
Add a new Buffer Deallocation pass replacing the old one with the goal of
inserting fewer clone operations and supporting additional use-cases.
Please refer to the Buffer Deallocation section in the updated
Bufferization.md file for more information on how this new pass works.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D158421
This is the first commit in a series with the goal to rework the
BufferDeallocation pass. Currently, this pass heavily relies on copies
to perform correct deallocations, which leads to very slow code and
potentially high memory usage. Additionally, there are unsupported cases
such as returning memrefs which this series of commits aims to add
support for as well.
This first commit removes the deallocation capabilities of
one-shot-bufferization.One-shot-bufferization should never deallocate any
memrefs as this should be entirely handled by the buffer-deallocation pass
going forward. This means the allow-return-allocs pass option will
default to true now, create-deallocs defaults to false and they, as well
as the escape attribute indicating whether a memref escapes the current region,
will be removed.
The documentation should w.r.t. these pass option changes should also be
updated in this commit.
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D156662
Zero ranked tensor (say tensor<i1>) when used for arith.select's condition,
crashes optimizer during bufferization. This patch puts a constraint on
condition to be either scalar or of matching shape as to its result.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D151270
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
All relevant operations have been switched to primarily use the strided
layout, but still support the affine map layout. Update the relevant
tests to use the strided format instead for compatibility with how ops
now print by default.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D134045
With the recent refactorings, this class is no longer needed. We can use BufferizationOptions in all places were BufferizationState was used.
Differential Revision: https://reviews.llvm.org/D127653
The buffer deallocation pass must now be run explicitly when `allow-return-alloc` is set.
This results in a few extra buffer copies in unoptimized test cases. The proper way to avoid such copies is to relax the OpOperand/OpResult aliasing contract on ops such as scf.for. Some of these copies can also be avoided by improving the buffer deallocation pass.
Differential Revision: https://reviews.llvm.org/D126252
This changes replaces the `fully-dynamic-layout-maps` options (which was badly named) with two new options:
* `unknown-type-conversion` controls the layout maps on buffer types for which no layout map can be inferred.
* `function-boundary-type-conversion` controls the layout maps on buffer types inside of function signatures.
Differential Revision: https://reviews.llvm.org/D125615
The last remaining operations in the standard dialect all revolve around
FuncOp/function related constructs. This patch simply handles the initial
renaming (which by itself is already huge), but there are a large number
of cleanups unlocked/necessary afterwards:
* Removing a bunch of unnecessary dependencies on Func
* Cleaning up the From/ToStandard conversion passes
* Preparing for the move of FuncOp to the Func dialect
See the discussion at https://discourse.llvm.org/t/standard-dialect-the-final-chapter/6061
Differential Revision: https://reviews.llvm.org/D120624
The bufferization of arith.constant ops is also switched over to BufferizableOpInterface-based bufferization. The old implementation is deleted. Both implementations utilize GlobalCreator, now renamed to just `getGlobalFor`.
GlobalCreator no longer maintains a set of all created allocations to avoid duplicate allocations of the same constant. Instead, `getGlobalFor` scans the module to see if there is already a global allocation with the same constant value.
For compatibility reasons, it is still possible to create a pass that bufferizes only `arith.constant`. This pass (createConstantBufferizePass) could be deleted once all users were switched over to One-Shot bufferization.
Differential Revision: https://reviews.llvm.org/D118483
The only benefit of FunctionPass is that it filters out function
declarations. This isn't enough to justify carrying it around, as we can
simplify filter out declarations when necessary within the pass. We can
also explore with better scheduling primitives to filter out declarations
at the pipeline level in the future.
The definition of FunctionPass is left intact for now to allow time for downstream
users to migrate.
Differential Revision: https://reviews.llvm.org/D117182
Precursor: https://reviews.llvm.org/D110200
Removed redundant ops from the standard dialect that were moved to the
`arith` or `math` dialects.
Renamed all instances of operations in the codebase and in tests.
Reviewed By: rriddle, jpienaar
Differential Revision: https://reviews.llvm.org/D110797
This has been a TODO for a long time, and it brings about many advantages (namely nice accessors, and less fragile code). The existing overloads that accept ArrayRef are now treated as deprecated and will be removed in a followup (after a small grace period). Most of the upstream MLIR usages have been fixed by this commit, the rest will be handled in a followup.
Differential Revision: https://reviews.llvm.org/D110293
This is the fourth and final patch in a series of patches fixing markdown links and references inside the mlir documentation. This patch combined with the other three should fix almost every broken link on mlir.llvm.org as far as I can tell.
This patch in particular addresses all Markdown files in the top level docs directory.
Differential Revision: https://reviews.llvm.org/D103032
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 spilts out BufferDeallocationInternals.md, since buffer
deallocation is not part of bufferization per se.
Differential Revision: https://reviews.llvm.org/D94351
Added documentation about the bufferization features.
Furthermore, the usage of pre- and post-processing is described.
This also includes information about optimization functionalities.
Differential Revision: https://reviews.llvm.org/D90675
