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.

See https://github.com/llvm/llvm-project/pull/147168 for more info.

Since `scf::tileUsingSCF` is the core method used for tiling the root
operation within the `scf::tileConsumersAndFuseProducersUsingSCF`, the
latter can fuse into any tiled loop generated using `scf::tileUsingSCF`.
This patch adds a test for tiling a root operation using
`ReductionTilingStrategy::PartialReductionOuterParallelStrategy` and
fusing producers with it.

Since this strategy generates a rank-reducing extract slice
`tensor::replaceExtractSliceWithTiledProducer` which is the core method
used for the fusion was extended to handle the rank-reducing slices.

Also fix a small bug in the computation of the reduction induction
variable (which needs to use `floorDiv` instead of `ceilDiv`)

Signed-off-by: MaheshRavishankar <mahesh.ravishankar@gmail.com>

For consumer fusion cases of this form

```
%0:2 = scf.forall .. shared_outs(%arg0 = ..., %arg0 = ...) {

  tensor.parallel_insert_slice ... into %arg0
  tensor.parallel_insert_slice ... into %arg1
}
%1 = linalg.generic ... ins(%0#0, %0#1)
```

the current consumer fusion that handles one slice at a time cannot fuse
the consumer into the loop, since fusing along one slice will create and
SSA violation on the other use from the `scf.forall`. The solution is to
allow consumer fusion to allow considering multiple slices at once. This
PR changes the `TilingInterface` methods related to consumer fusion,
i.e.

- `getTiledImplementationFromOperandTile`
- `getIterationDomainFromOperandTile`

to allow fusion while considering multiple operands. It is upto the
`TilingInterface` implementation to return an error if a list of tiles
of the operands cannot result in a consistent implementation of the
tiled operation.

The Linalg operation implementation of `TilingInterface` has been
modified to account for these changes and allow cases where operand
tiles that can result in a consistent tiling implementation are handled.

---------

Signed-off-by: MaheshRavishankar <mahesh.ravishankar@gmail.com>

The revision adds isOneInteger helper, and simplifies the existing code
with the two methods. It removes some lambda, which makes code cleaner.

For downstream users, you can update the code with the below script.

```bash
sed -i "s/isZeroIndex/isZeroInteger/g" **/*.h
sed -i "s/isZeroIndex/isZeroInteger/g" **/*.cpp
```

---------

Signed-off-by: hanhanW <hanhan0912@gmail.com>

This commit adds an API (`tileAndFuseConsumerOfSlice`) to fuse consumer to a producer within
scf.for/scf.forall loop.

To support this two new methods are added to the `TilingInterface`
- `getIterationDomainTileFromOperandTile`
- `getTiledImplementationFromOperandTile`.

Consumer operations that implement this method can be used to be fused with tiled producer operands in a manner similar to (but essentially the inverse of) the fusion of an untiled producer with a tiled consumer.

Note that this only does one `tiled producer` -> `consumer` fusion. This could be called repeatedly for fusing multiple consumers. The current implementation also is conservative in when this kicks in (like single use of the value returned by the inter-tile loops that surround the tiled producer, etc.) These can be relaxed over time.

Signed-off-by: Abhishek Varma <abhvarma@amd.com>

---------

Signed-off-by: Abhishek Varma <abhvarma@amd.com>
Signed-off-by: Abhishek Varma <avarma094@gmail.com>
Co-authored-by: cxy <chenxunyu1993@gmail.com>

Currently the `getTiledImplementation` and `generateResultTileValue`
return just `SmallVector<Operation *>` and `FailureOr<Value>`.

- For `getTiledImplementation` returning empty implies tiling wasnt
  done. There is also an implicit assumption that the tiled operation
  results correspond to the tiled values of the result of the original
  operation. This cannot handle cases where the tiled implementation
  might use multiple operations to compute the tiled value for the
  results of the untiled operation. Sometimes, the tiled operation
  might not directly give the tiled values, and might require casts,
  etc to get a replacement.
- For `generateResultTileValue`, it is assumed that the op defining
  the returned `Value` is the operation that represents the tiled
  computation. Again presence of casts, etc violate this.

Instead make these methods return
```
struct TilingResult {
  SmallVector<Operation *> tiledOps;
  SmallVector<Value> tiledValues;
};
```

The `tiledOps` represent the operations generated that are relevant
for subsequent transformations. The `tiledValues` represent the tiled
values for the results of the original operation. This better
transmits the state of the transformed IR.

As a consequence the following methods also return `FailureOr<TilingResult>`
- `tensor::replaceExtractSliceWithTiledProducer`
- `tensor::bubbleUpPadSlice`

Differential Revision: https://reviews.llvm.org/D145133

std::optional::value() has undesired exception checking semantics and is
unavailable in older Xcode (see _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS). The
call sites block std::optional migration.

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