Previously, ExecuteRegionOps with multiple return values would fail a round-trip test due to missing parenthesis around the types.
Differential Revision: https://reviews.llvm.org/D108402
This CL adds a new RegionBranchTerminatorOpInterface to query information about operands that can be
passed to successor regions. Similar to the BranchOpInterface, it allows to freely define the
involved operands. However, in contrast to the BranchOpInterface, it expects an additional region
number to distinguish between various use cases which might require different operands passed to
different regions.
Moreover, we added new utility functions (namely getMutableRegionBranchSuccessorOperands and
getRegionBranchSuccessorOperands) to query (mutable) operand ranges for operations equiped with the
ReturnLike trait and/or implementing the newly added interface. This simplifies reasoning about
terminators in the scope of the nested regions.
We also adjusted the SCF.ConditionOp to benefit from the newly added capabilities.
Differential Revision: https://reviews.llvm.org/D105018
The executeregionop is used to allow multiple blocks within SCF constructs. If the container allows multiple blocks, inline the region
Differential Revision: https://reviews.llvm.org/D104960
* Previously, we were only generating .h.inc files. We foresee the need to also generate implementations and this is a step towards that.
* Discussed in https://llvm.discourse.group/t/generating-cpp-inc-files-for-dialects/3732/2
* Deviates from the discussion above by generating a default constructor in the .cpp.inc file (and adding a tablegen bit that disables this in case if this is user provided).
* Generating the destructor started as a way to flush out the missing includes (produces a link error), but it is a strict improvement on its own that is worth doing (i.e. by emitting key methods in the .cpp file, we root vtables in one translation unit, which is a non-controversial improvement).
Differential Revision: https://reviews.llvm.org/D105070
The executeregionop is used to allow multiple blocks within SCF constructs. If the container allows multiple blocks, inline the region
Differential Revision: https://reviews.llvm.org/D104960
Introduce the execute_region op that is able to hold a region which it
executes exactly once. The op encapsulates a CFG within itself while
isolating it from the surrounding control flow. Proposal discussed here:
https://llvm.discourse.group/t/introduce-std-inlined-call-op-proposal/282
execute_region enables one to inline a function without lowering out all
other higher level control flow constructs (affine.for/if, scf.for/if)
to the flat list of blocks / CFG form. It thus allows the benefit of
transforms on higher level control flow ops available in the presence of
the inlined calls. The inlined calls continue to benefit from
propagation of SSA values across their top boundary. Functions won’t
have to remain outlined until later than desired. Abstractions like
affine execute_regions, lambdas with implicit captures could be lowered
to this without first lowering out structured loops/ifs or outlining.
But two potential early use cases are of: (1) an early inliner (which
can inline functions by introducing execute_region ops), (2) lowering of
an affine.execute_region, which cleanly maps to an scf.execute_region
when going from the affine dialect to the scf dialect.
Differential Revision: https://reviews.llvm.org/D75837
Add two canoncalizations for scf.if.
1) A canonicalization that allows users of a condition within an if to assume the condition
is true if in the true region, etc.
2) A canonicalization that removes yielded statements that are equivalent to the condition
or its negation
Differential Revision: https://reviews.llvm.org/D101012
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
* Do we need a threshold on maximum number of Yeild arguments processed (maximum number of SelectOp's to be generated)?
* Had to modify some old IfOp tests to not get optimized by this pattern
Differential Revision: https://reviews.llvm.org/D98592
'ForOpIterArgsFolder' can now remove iterator arguments (and corresponding
results) with no use.
Example:
```
%cst = constant 32 : i32
%0:2 = scf.for %arg1 = %lb to %ub step %step iter_args(%arg2 = %arg0, %arg3 = %cst)
-> (i32, i32) {
%1 = addu %arg2, %cst : i32
scf.yield %1, %1 : i32, i32
}
use(%0#0)
```
%arg3 is not used in the block, and its corresponding result `%0#1` has no use,
thus remove the iter argument.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D98711
Enhance 'ForOpIterArgsFolder' to remove unused iteration arguments in a
scf::ForOp. If the block argument corresponding to the given iterator has no
use and the yielded value equals the input, we fold it away.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D98503
Canonicalize the iter_args of an scf::ForOp that involve a tensor_load and
for which only the last loop iteration is actually visible outside of the
loop. The canonicalization looks for a pattern such as:
```
%t0 = ... : tensor_type
%0 = scf.for ... iter_args(%bb0 : %t0) -> (tensor_type) {
...
// %m is either tensor_to_memref(%bb00) or defined above the loop
%m... : memref_type
... // uses of %m with potential inplace updates
%new_tensor = tensor_load %m : memref_type
...
scf.yield %new_tensor : tensor_type
}
```
`%bb0` may have either 0 or 1 use. If it has 1 use it must be exactly a
`%m = tensor_to_memref %bb0` op that feeds into the yielded `tensor_load`
op.
If no aliasing write of `%new_tensor` occurs between tensor_load and yield
then the value %0 visible outside of the loop is the last `tensor_load`
produced in the loop.
For now, we approximate the absence of aliasing by only supporting the case
when the tensor_load is the operation immediately preceding the yield.
The canonicalization rewrites the pattern as:
```
// %m is either a tensor_to_memref or defined above
%m... : memref_type
scf.for ... { // no iter_args
... // uses of %m with potential inplace updates
}
%0 = tensor_load %m : memref_type
```
Differential revision: https://reviews.llvm.org/D97953
Previously this might happen if there was no elseRegion and the method
was asked for all successor regions.
Differential Revision: https://reviews.llvm.org/D96764
We should be check whether lb + step >= ub to determine
whether this is a single iteration. Previously we were
checking lb + lb >= ub.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D95440
We should be check whether lb + step >= ub to determine
whether this is a single iteration. Previously we were
checking lb + lb >= ub.
Differential Revision: https://reviews.llvm.org/D95440
Given that OpState already implicit converts to Operator*, this seems reasonable.
The alternative would be to add more functions to OpState which forward to Operation.
Reviewed By: rriddle, ftynse
Differential Revision: https://reviews.llvm.org/D92266
An SCF 'for' loop does not iterate if its lower bound is equal to its upper
bound. Remove loops where both bounds are the same SSA value as such bounds are
guaranteed to be equal. Similarly, remove 'parallel' loops where at least one
pair of respective lower/upper bounds is specified by the same SSA value.
Reviewed By: gysit
Differential Revision: https://reviews.llvm.org/D91880
Add canoncalization patterns to remove zero-iteration 'for' loops, replace
single-iteration 'for' loops with their bodies; remove known-false conditionals
with no 'else' branch and replace conditionals with known value by the
respective region. Although similar transformations are performed at the CFG
level, not all flows reach that level, e.g., the GPU flow may want to remove
single-iteration loops before deciding on loop mapping to thread dimensions.
Reviewed By: herhut
Differential Revision: https://reviews.llvm.org/D91865
scf.parallel is currently not a good fit for tiling on tensors.
Instead provide a path to parallelism directly through scf.for.
For now, this transformation ignores the distribution scheme and always does a block-cyclic mapping (where block is the tile size).
Differential revision: https://reviews.llvm.org/D90475
The new construct represents a generic loop with two regions: one executed
before the loop condition is verifier and another after that. This construct
can be used to express both a "while" loop and a "do-while" loop, depending on
where the main payload is located. It is intended as an intermediate
abstraction for lowering, which will be added later. This form is relatively
easy to target from higher-level abstractions and supports transformations such
as loop rotation and LICM.
Differential Revision: https://reviews.llvm.org/D90255
Often times the legality of inlining can change depending on if the callable is going to be inlined in-place, or cloned. For example, some operations are not allowed to be duplicated and can only be inlined if the original callable will cease to exist afterwards. The new `wouldBeCloned` flag allows for dialects to hook into this when determining legality.
Differential Revision: https://reviews.llvm.org/D90360
The patch adds a canonicalization pattern that removes the unused results of scf.if operation. As a result, cse may remove unused computations in the then and else regions of the scf.if operation.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D89029
Now backends spell out which namespace they want to be in, instead of relying on
clients #including them inside already-opened namespaces. This also means that
cppNamespaces should be fully qualified, and there's no implicit "::mlir::"
prepended to them anymore.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D86811
With `dynamic_tensor_from_elements` tensor values of dynamic size can be
created. The body of the operation essentially maps the index space to tensor
elements.
Declare SCF operations in the `scf` namespace to avoid name clash with the new
`std.yield` operation. Resolve ambiguities between `linalg/shape/std/scf.yield`
operations.
Differential Revision: https://reviews.llvm.org/D86276
This patch moves the registration to a method in the MLIRContext: getOrCreateDialect<ConcreteDialect>()
This method requires dialect to provide a static getDialectNamespace()
and store a TypeID on the Dialect itself, which allows to lazyily
create a dialect when not yet loaded in the context.
As a side effect, it means that duplicated registration of the same
dialect is not an issue anymore.
To limit the boilerplate, TableGen dialect generation is modified to
emit the constructor entirely and invoke separately a "init()" method
that the user implements.
Differential Revision: https://reviews.llvm.org/D85495
- Add function `verifyTypes` that Op's can call to do type checking verification
along the control flow edges described the Op's RegionBranchOpInterface.
- We cannot rely on the verify methods on the OpInterface because the interface
functions assume valid Ops, so they may crash if invoked on unverified Ops.
(For example, scf.for getSuccessorRegions() calls getRegionIterArgs(), which
dereferences getBody() block. If the scf.for is invalid with no body, this
can lead to a segfault). `verifyTypes` can be called post op-verification to
avoid this.
Differential Revision: https://reviews.llvm.org/D82829
Similarly to `scf::ForOp`, introduce additional `function_ref` arguments to
`::build` functions of SCF `ParallelOp` and `ReduceOp`. The provided functions
will be called to construct the body of the respective operations while
constructing the operation itself. Exercise them in LoopUtils.
Differential Revision: https://reviews.llvm.org/D81872
This simplifies a lot of handling of BoolAttr/IntegerAttr. For example, a lot of places currently have to handle both IntegerAttr and BoolAttr. In other places, a decision is made to pick one which can lead to surprising results for users. For example, DenseElementsAttr currently uses BoolAttr for i1 even if the user initialized it with an Array of i1 IntegerAttrs.
Differential Revision: https://reviews.llvm.org/D81047
Morten Borup Petersen