This commit simplifies the implementation of the
`ValueBoundsOpInterface` for `scf.for` based on the newly added
`ValueBoundsConstraintSet::compare` API and adds additional
documentation.
Previously, the interface implementation created a new constraint set
just to check if the yielded value and iter_arg are equal. This was
inefficient because constraints were added multiple times (to two
different constraint sets) for ops that are inside the loop.
Note: This is a re-upload of #86239.
This commit adds support for `scf.if` to `ValueBoundsConstraintSet`.
Example:
```
%0 = scf.if ... -> index {
scf.yield %a : index
} else {
scf.yield %b : index
}
```
The following constraints hold for %0:
* %0 >= min(%a, %b)
* %0 <= max(%a, %b)
Such constraints cannot be added to the constraint set; min/max is not
supported by `IntegerRelation`. However, if we know which one of %a and
%b is larger, we can add constraints for %0. E.g., if %a <= %b:
* %0 >= %a
* %0 <= %b
This commit required a few minor changes to the
`ValueBoundsConstraintSet` infrastructure, so that values can be
compared while we are still in the process of traversing the IR/adding
constraints.
Note: This is a re-upload of #85895, which was reverted. The bug that
caused the failure was fixed in #87859.
This commit simplifies the implementation of the
`ValueBoundsOpInterface` for `scf.for` based on the newly added
`ValueBoundsConstraintSet::compare` API and adds additional
documentation.
Previously, the interface implementation created a new constraint set
just to check if the yielded value and iter_arg are equal. This was
inefficient because constraints were added multiple times (to two
different constraint sets) for ops that are inside the loop.
This commit adds support for `scf.if` to `ValueBoundsConstraintSet`.
Example:
```
%0 = scf.if ... -> index {
scf.yield %a : index
} else {
scf.yield %b : index
}
```
The following constraints hold for %0:
* %0 >= min(%a, %b)
* %0 <= max(%a, %b)
Such constraints cannot be added to the constraint set; min/max is not
supported by `IntegerRelation`. However, if we know which one of %a and
%b is larger, we can add constraints for %0. E.g., if %a <= %b:
* %0 >= %a
* %0 <= %b
This commit required a few minor changes to the
`ValueBoundsConstraintSet` infrastructure, so that values can be
compared while we are still in the process of traversing the IR/adding
constraints.
This commit changes the API of `ValueBoundsConstraintSet`: the stop
condition is now passed to the constructor instead of `processWorklist`.
That makes it easier to add items to the worklist multiple times and
process them in a consistent manner. The current
`ValueBoundsConstraintSet` is passed as a reference to the stop
function, so that the stop function can be defined before the the
`ValueBoundsConstraintSet` is constructed.
This change is in preparation of adding support for branches.
This commit implements `LoopLikeOpInterface` on `scf.while`. This
enables LICM (and potentially other transforms) on `scf.while`.
`LoopLikeOpInterface::getLoopBody()` is renamed to `getLoopRegions` and
can now return multiple regions.
Also fix a bug in the default implementation of
`LoopLikeOpInterface::isDefinedOutsideOfLoop()`, which returned "false"
for some values that are defined outside of the loop (in a nested op, in
such a way that the value does not dominate the loop). This interface is
currently only used for LICM and there is no way to trigger this bug, so
no test is added.
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 follows a previous patch that updated calls
`op.cast<T>()-> cast<T>(op)`. However some cases could not handle an
unprefixed `cast` call due to occurrences of variables named cast, or
occurring inside of class definitions which would resolve to the method.
All C++ files that did not work automatically with `cast<T>()` are
updated here to `llvm::cast` and similar with the intention that they
can be easily updated after the methods are removed through a
find-replace.
See https://github.com/llvm/llvm-project/compare/main...tpopp:llvm-project:tidy-cast-check
for the clang-tidy check that is used and then update printed
occurrences of the function to include `llvm::` before.
One can then run the following:
```
ninja -C $BUILD_DIR clang-tidy
run-clang-tidy -clang-tidy-binary=$BUILD_DIR/bin/clang-tidy -checks='-*,misc-cast-functions'\
-export-fixes /tmp/cast/casts.yaml mlir/*\
-header-filter=mlir/ -fix
rm -rf $BUILD_DIR/tools/mlir/**/*.inc
```
Differential Revision: https://reviews.llvm.org/D150348
If an `scf.for` loop yields an equal index-typed value or a shaped value with the same dimension sizes (in comparison to the corresponding iter_arg), bounds can be computed for the iter_arg and the OpResult of the `scf.for` op.
Differential Revision: https://reviews.llvm.org/D146306
