30 Commits

Author SHA1 Message Date
Mehdi Amini
acbf3f3186
[MLIR][SCF] Fix scf.index_switch lowering to preserve large case values (#189230)
`IndexSwitchLowering` stored case values as `SmallVector<int32_t>`,
which silently truncated any `int64_t` case value larger than INT32_MAX
(e.g. `4294967296` became `0`). The `cf.switch` flag was also created
via `arith.index_cast index -> i32`, losing the upper 32 bits on 64-bit
platforms.

Fix: store case values as `SmallVector<APInt>` with 64-bit width, cast
the index argument to `i64`, and use the `ArrayRef<APInt>` overload of
`cf::SwitchOp::create` so the resulting switch correctly uses `i64` case
values and flag type.

Fixes #111589

Assisted-by: Claude Code
2026-03-31 00:46:28 +02:00
Matthias Springer
5327c6b57e
[mlir][SCF] Add pass option to deactivate pattern rollback (#168481)
Add a pass option to `convert-scf-to-cf` to deactivate pattern rollback
for better performance. The lowering patterns from SCF->CF to benefit a
lot from this feature because `splitBlock` is expensive in the rollback
driver.
2025-11-18 16:08:27 +08:00
Matthias Springer
21b607adbe
[mlir][SCF] scf.for: Add support for unsigned integer comparison (#153379)
Add a new unit attribute to allow for unsigned integer comparison.

Example:
```mlir
scf.for unsigned %iv_32 = %lb_32 to %ub_32 step %step_32 : i32 {
  // body
}
```

Discussion:
https://discourse.llvm.org/t/scf-should-scf-for-support-unsigned-comparison/84655
2025-08-15 10:59:14 +02:00
Thomas Raoux
0b37de2968
[MLIR][SCF] Propagate loop annotation during while op lowering (#151746)
This is expanding on https://github.com/llvm/llvm-project/pull/102562 

This allows also propagating attributes for scf.while lowering
2025-08-01 12:14:58 -07:00
Matthias Springer
cccde9b2b1
[mlir][SCF] Do not access erased operation in scf.while lowering (#150741)
Do not access the erased `scf.while` operation in the lowering pattern.
That won't work anymore in a One-Shot Dialect Conversion and triggers a
use-after-free sanitizer error.

After the One-Shot Dialect Conversion refactoring, a
`ConversionPatternRewriter` will behave more like a normal
`PatternRewriter`.
2025-07-26 11:07:06 +02:00
Maksim Levental
38976a03cd
[mlir][NFC] update Conversion create APIs (7/n) (#149889)
See https://github.com/llvm/llvm-project/pull/147168 for more info.
2025-07-22 10:41:06 -04:00
Matthias Springer
7f7cf2743a
[mlir][SCF] Do not access erased op in scf.while lowering (#148356)
Do not access the erased `scf.condition` operation in the lowering
pattern. That won't work anymore in a One-Shot Dialect Conversion and
triggers a use-after-free sanitizer error.

After the One-Shot Dialect Conversion refactoring, a
`ConversionPatternRewriter` will behave more like a normal
`PatternRewriter`.
2025-07-12 16:14:04 +02:00
Menooker
18b409558a
[mlir] [scf-to-cf] attach the loop annotation to latch block (#147462)
As [required by LLVM](https://llvm.org/docs/LangRef.html#llvm-loop), the
loop annotation (loop metadata) should be attached on the ["latch"
block](https://llvm.org/docs/LoopTerminology.html). Otherwise, the
annotation might be ignored by LLVM. This PR fixes this issue.
2025-07-09 12:07:35 +08:00
Kazu Hirata
fa9adbfda9
[mlir] Remove unused includes (NFC) (#147101)
These are identified by misc-include-cleaner.  I've filtered out those
that break builds.  Also, I'm staying away from llvm-config.h,
config.h, and Compiler.h, which likely cause platform- or
compiler-specific build failures.
2025-07-04 13:30:21 -07:00
lorenzo chelini
c1a2292526
[MLIR][NFC] Retire let constructor for passes in Conversion directory (part1) (#127403)
`let constructor` is deprecated since the table gen backend emits most
of the glue logic to build a pass. This PR retires the td method for
most (I need another pass) passes in the Conversion directory.
2025-02-17 10:55:27 +01:00
donald chen
c02fd17c1e
[mlir] [scf] fix crash when conversion from scf to control flow (#107221)
This patch fixed a crash when scf.parallel's region donesn't terminate
with reduce op. This can happend in dialect conversion.
2024-09-06 10:02:05 +08:00
Christopher Bate
06fd808654 Revert "[mlir] NFC: fix dependence of (Tensor|Linalg|MemRef|Complex) dialects on LLVM Dialect and LLVM Core in CMake build (#104832)"
This reverts commit 43b508566799751aa180f1eaaafc5be693f2f1ae since it
caused the build to break with BUILD_SHARED_LIBS=ON.
2024-08-20 03:46:29 +00:00
Christopher Bate
43b5085667
[mlir] NFC: fix dependence of (Tensor|Linalg|MemRef|Complex) dialects on LLVM Dialect and LLVM Core in CMake build (#104832)
This change removes dependencies declared as either 'LINK_LIBS' or
'LINK_COMPONENTS' across several MLIR libraries. The removed
dependencies appear
to be incorrect and may have been required in older versions of the
project.
These dependencies cause many high level dialects to have transitive
dependence on the LLVM dialect and the LLVM 'Core' library
('llvm/lib/IR').

Note that if using the 'Ninja' CMake generator, one can inspect the
dependencies
(including all transitive libraries) of any given MLIR target but using
the command `ninja -C <build dir> -t browse` and navigating to the
library
of interest in a web browser.
2024-08-19 18:49:22 -06:00
xiaoleis-nv
fbf81e3004
Enable attaching LLVM loop annotations to scf.for (#102562)
We recently discovered that the loop with a dynamic upper bound is
unexpectedly unrolled during the NVVM to PTX process. By attaching the
`llvm.loop_annotation`, we can control the unrolling behavior precisely.

This PR enables the `cf.cond_br` to retain the loop annotation of
`scf.for` after the `convert-scf-to-cf` pass. This change allows users
to have precise control over the loop behavior during backend
transformation.

---------

Co-authored-by: Xiaolei Shi <xiaoleis@nvidia.com>
2024-08-12 18:25:13 +02:00
Spenser Bauman
0b665c3dd2
[mlir][scf] Implement conversion from scf.forall to scf.parallel (#94109)
There is currently no path to lower scf.forall to scf.parallel with the
goal of targeting the OpenMP dialect.

In the SCF->ControlFlow conversion, scf.forall is briefly converted to
scf.parallel, but the scf.parallel is lowered directly to a sequential
loop. This makes experimenting with scf.forall for CPU execution
difficult.

This change factors out the rewrite in the SCF->ControlFlow pass into a
utility function that can then be used in the SCF->ControlFlow lowering
and via a separate -scf-forall-to-parallel pass.

---------

Co-authored-by: Spenser Bauman <sabauma@fastmail>
2024-06-04 15:41:09 -04:00
Matthias Springer
10056c821a
[mlir][SCF] scf.parallel: Make reductions part of the terminator (#75314)
This commit makes reductions part of the terminator. Instead of
`scf.yield`, `scf.reduce` now terminates the body of `scf.parallel` ops.
`scf.reduce` may contain an arbitrary number of reductions, with one
region per reduction.

Example:
```mlir
%init = arith.constant 0.0 : f32
%r:2 = scf.parallel (%iv) = (%lb) to (%ub) step (%step) init (%init, %init)
    -> f32, f32 {
  %elem_to_reduce1 = load %buffer1[%iv] : memref<100xf32>
  %elem_to_reduce2 = load %buffer2[%iv] : memref<100xf32>
  scf.reduce(%elem_to_reduce1, %elem_to_reduce2 : f32, f32) {
    ^bb0(%lhs : f32, %rhs: f32):
      %res = arith.addf %lhs, %rhs : f32
      scf.reduce.return %res : f32
  }, {
    ^bb0(%lhs : f32, %rhs: f32):
      %res = arith.mulf %lhs, %rhs : f32
      scf.reduce.return %res : f32
  }
}
```

`scf.reduce` operations can no longer be interleaved with other ops in
the body of `scf.parallel`. This simplifies the op and makes it possible
to assign the `RecursiveMemoryEffects` trait to `scf.reduce`. (This was
not possible before because the op was not a terminator, causing the op
to be DCE'd.)
2023-12-20 11:06:27 +09:00
Matthias Springer
5cf714bb2f
[mlir][SCF] scf.for: Consistent API around initArgs (#66512)
* Always use the auto-generated `getInitArgs` function. Remove the
hand-written `getInitOperands` duplicate.
* Remove `hasIterOperands` and `getNumIterOperands`. The names were
inconsistent because the "arg" is called `initArgs` in TableGen. Use
`getInitArgs().size()` instead.
* Fix verification around ops with no results.
2023-09-18 09:13:43 +02:00
Matthias Springer
87568ff3ef
[mlir][SCF] convert-scf-to-cf: Lower scf.forall to scf.parallel (#65449)
scf.forall ops without shared outputs (i.e., fully bufferized ops) are
lowered to scf.parallel. scf.forall ops are typically lowered by an
earlier pass depending on the execution target. E.g., there are
optimized lowerings for GPU execution. This new lowering is for
completeness (convert-scf-to-cf can now lower all SCF loop constructs)
and provides a simple CPU lowering strategy for testing purposes.

scf.parallel is currently lowered to scf.for, which executes
sequentially. The scf.parallel lowering could be improved in the future
to run on multiple threads.
2023-09-06 13:27:59 +02:00
Eugene Zhulenev
03b43d3dfb Fix scf-to-cfg conversion for IndexSwitchOp
Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D158212
2023-08-18 16:18:43 -07:00
Matthias Springer
7c74a2507c [mlir][SCF][NFC] Add helper functions to get body of scf.while
Add two new helper functions `getBeforeBody` and `getAfterBody` to be consistent with "scf.for" (`getBody`) and to show in the API that both regions have exactly one block. Also simplify some code that assumed that there can be more than one block in a region.

Differential Revision: https://reviews.llvm.org/D157860
2023-08-14 14:57:09 +02:00
Matthias Springer
42c31d8302 [mlir][IR] Clean up mergeBlockBefore and mergeBlocks
* `RewriterBase::mergeBlocks` is simplified: it is implemented in terms of `mergeBlockBefore`.
* The signature of `mergeBlockBefore` is consistent with other API (such as `inlineRegionBefore`): an overload for a `Block::iterator` is added.
* Additional safety checks are added to `mergeBlockBefore`: detect cases where the resulting IR could be invalid (no more `dropAllUses`) or partly unreachable (likely a case of incorrect API usage).
* Rename `mergeBlockBefore` to `inlineBlockBefore`.

Differential Revision: https://reviews.llvm.org/D144969
2023-03-06 13:46:08 +01:00
Jeff Niu
4d67b27817 [mlir] Add operations to BlockAndValueMapping and rename it to IRMapping
The patch adds operations to `BlockAndValueMapping` and renames it to `IRMapping`. When operations are cloned, old operations are mapped to the cloned operations. This allows mapping from an operation to a cloned operation. Example:

```
Operation *opWithRegion = ...
Operation *opInsideRegion = &opWithRegion->front().front();

IRMapping map
Operation *newOpWithRegion = opWithRegion->clone(map);
Operation *newOpInsideRegion = map.lookupOrNull(opInsideRegion);
```

Migration instructions:
All includes to `mlir/IR/BlockAndValueMapping.h` should be replaced with `mlir/IR/IRMapping.h`. All uses of `BlockAndValueMapping` need to be renamed to `IRMapping`.

Reviewed By: rriddle, mehdi_amini

Differential Revision: https://reviews.llvm.org/D139665
2023-01-12 13:16:05 -08:00
Jeff Niu
91effec852 [mlir][scf] Add scf-to-cf lowering for scf.index_switch
This patch adds lowering from `scf.index_switch` to `cf.switch.

Reviewed By: rriddle

Differential Revision: https://reviews.llvm.org/D136883
2022-10-31 12:01:22 -07:00
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
Michele Scuttari
67d0d7ac0a
[MLIR] Update pass declarations to new autogenerated files
The patch introduces the required changes to update the pass declarations and definitions to use the new autogenerated files and allow dropping the old infrastructure.

Reviewed By: mehdi_amini, rriddle

Differential Review: https://reviews.llvm.org/D132838
2022-08-31 12:28:45 +02:00
Michele Scuttari
039b969b32
Revert "[MLIR] Update pass declarations to new autogenerated files"
This reverts commit 2be8af8f0e0780901213b6fd3013a5268ddc3359.
2022-08-30 22:21:55 +02:00
Michele Scuttari
2be8af8f0e
[MLIR] Update pass declarations to new autogenerated files
The patch introduces the required changes to update the pass declarations and definitions to use the new autogenerated files and allow dropping the old infrastructure.

Reviewed By: mehdi_amini, rriddle

Differential Review: https://reviews.llvm.org/D132838
2022-08-30 21:56:31 +02:00
Benjamin Kramer
9fa59e7643 [mlir] Use C++17 structured bindings instead of std::tie where applicable. NFCI 2022-08-09 13:34:17 +02:00
Alex Zinenko
8b68da2c7d [mlir] move SCF headers to SCF/{IR,Transforms} respectively
This aligns the SCF dialect file layout with the majority of the dialects.

Reviewed By: jpienaar

Differential Revision: https://reviews.llvm.org/D128049
2022-06-20 10:18:01 +02:00
River Riddle
ace01605e0 [mlir] Split out a new ControlFlow dialect from Standard
This dialect is intended to model lower level/branch based control-flow constructs. The initial set
of operations are: AssertOp, BranchOp, CondBranchOp, SwitchOp; all split out from the current
standard dialect.

See https://discourse.llvm.org/t/standard-dialect-the-final-chapter/6061

Differential Revision: https://reviews.llvm.org/D118966
2022-02-06 14:51:16 -08:00