This covers more options for CSE. It also ensures that two operations
that have same operands but different regions to begin with, but same
regions after `simplifyRegions`, don't get both added to the list of
`knownValues`.
Fixes#59135
Differential Revision: https://reviews.llvm.org/D139490
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
Ops that were modifed in-place (`finalizeRootUpdate` was called) should be reprocessed by the GreedyPatternRewriter. This is currently not happening with `GreedyRewriteConfig::maxIterations = 1`.
Note: If your project goes into an infinite loop because of this change, you likely have one or multiple faulty patterns that modify the same operations in-place (`updateRootInplace`) indefinitely.
Differential Revision: https://reviews.llvm.org/D138038
Currently CSE does not support CSE of ops with regions. This patch
extends the CSE support to ops with a single region.
Differential Revision: https://reviews.llvm.org/D134306
Depends on D137857
The methods in `SideEffectUtils.h` (and their implementations in
`SideEffectUtils.cpp`) seem to have similar intent to methods already
existing in `SideEffectInterfaces.h`. Move the decleration (and
implementation) from `SideEffectUtils.h` (and `SideEffectUtils.cpp`)
into `SideEffectInterfaces.h` (and `SideEffectInterface.cpp`).
Also drop the `SideEffectInterface::hasNoEffect` method in favor of
`mlir::isMemoryEffectFree` which actually recurses into the operation
instead of just relying on the `hasRecursiveMemoryEffectTrait`
exclusively.
Differential Revision: https://reviews.llvm.org/D137857
Up until now PDL(L) has not supported dialect conversion because we had no
way of remapping values or integrating with type conversions. This commit
rectifies that by adding a new "pattern configuration" concept to PDL. This
essentially allows for attaching external configurations to patterns, which
can hook into pattern events (for now just the scope of a rewrite, but we
could also pass configs to native rewrites as well). This allows for injecting
the type converter into the conversion pattern rewriter.
Differential Revision: https://reviews.llvm.org/D133142
This code, on all platforms was a use-after-move violation that resulted
in the if-statement always returning false. As several core tests specifically
tested that this code did not execute, we assume that is the intent and
match behavior to existing behavior without relying on use-after-move
results.
Without the llvm_unreachable, Windows complains about not returning a
value from mlir::isSpeculatable on all paths.
Differential Revision: https://reviews.llvm.org/D135899
This change allows analyzing ops from different block, in particular when used in programs that have `cf` branches.
Differential Revision: https://reviews.llvm.org/D135644
This patch takes the first step towards a more principled modeling of undefined behavior in MLIR as discussed in the following discourse threads:
1. https://discourse.llvm.org/t/semantics-modeling-undefined-behavior-and-side-effects/4812
2. https://discourse.llvm.org/t/rfc-mark-tensor-dim-and-memref-dim-as-side-effecting/65729
This patch in particular does the following:
1. Introduces a ConditionallySpeculatable OpInterface that dynamically determines whether an Operation can be speculated.
2. Re-defines `NoSideEffect` to allow undefined behavior, making it necessary but not sufficient for speculation. Also renames it to `NoMemoryEffect`.
3. Makes LICM respect the above semantics.
4. Changes all ops tagged with `NoSideEffect` today to additionally implement ConditionallySpeculatable and mark themselves as always speculatable. This combined trait is named `Pure`. This makes this change NFC.
For out of tree dialects:
1. Replace `NoSideEffect` with `Pure` if the operation does not have any memory effects, undefined behavior or infinite loops.
2. Replace `NoSideEffect` with `NoSideEffect` otherwise.
The next steps in this process are (I'm proposing to do these in upcoming patches):
1. Update operations like `tensor.dim`, `memref.dim`, `scf.for`, `affine.for` to implement a correct hook for `ConditionallySpeculatable`. I'm also happy to update ops in other dialects if the respective dialect owners would like to and can give me some pointers.
2. Update other passes that speculate operations to consult `ConditionallySpeculatable` in addition to `NoMemoryEffect`. I could not find any other than LICM on a quick skim, but I could have missed some.
3. Add some documentation / FAQs detailing the differences between side effects, undefined behavior, speculatabilty.
Reviewed By: rriddle, mehdi_amini
Differential Revision: https://reviews.llvm.org/D135505
This is much more explicit, and prevents annoying conflicts with op
specific accessors (which may have a different contract). This is similar
to the past rename of getType -> getFunctionType,
Fixes#58030
Differential Revision: https://reviews.llvm.org/D135007
It is useful for PatternRewriter listeners to know the values that are
replacing the op in addition to only the fact of the op being replaced
for being able to keep track of changes or for debugging.
Reviewed By: Mogball
Differential Revision: https://reviews.llvm.org/D134748
I'm planning to deprecate and eventually remove llvm::empty.
Note that no use of llvm::empty requires the ability of llvm::empty to
determine the emptiness from begin/end only.
Currently, for sparse analyses, we always store a `Optional<ValueT>` in each lattice element. When it's `None`, we consider the lattice element as `uninitialized`.
However:
* Not all lattices have an `uninitialized` state. For example, `Executable` and `PredecessorState` have default values so they are always initialized.
* In dense analyses, we don't have the concept of an `uninitialized` state.
Given these inconsistencies, this patch removes `Lattice::isUninitialized()`. Individual analysis states are now default-constructed. If the default state of an analysis can be considered as "uninitialized" then this analysis should implement the following logic:
* Special join rule: `join(uninitialized, any) == any`.
* Special bail out logic: if any of the input states is uninitialized, exit the transfer function early.
Depends On D132086
Reviewed By: Mogball
Differential Revision: https://reviews.llvm.org/D132800
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
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
This change add a helper function for computing a topological sorting of a list of ops. E.g. this can be useful in transforms where a subset of ops should be cloned without dominance errors.
The analysis reuses the existing implementation in TopologicalSortUtils.cpp.
Differential Revision: https://reviews.llvm.org/D131669
Added a commutativity utility pattern and a function to populate it. The pattern sorts the operands of an op in ascending order of the "key" associated with each operand iff the op is commutative. This sorting is stable.
The function is intended to be used inside passes to simplify the matching of commutative operations. After the application of the above-mentioned pattern, since the commutative operands now have a deterministic order in which they occur in an op, the matching of large DAGs becomes much simpler, i.e., requires much less number of checks to be written by a user in her/his pattern matching function.
The "key" associated with an operand is the list of the "AncestorKeys" associated with the ancestors of this operand, in a breadth-first order.
The operand of any op is produced by a set of ops and block arguments. Each of these ops and block arguments is called an "ancestor" of this operand.
Now, the "AncestorKey" associated with:
1. A block argument is `{type: BLOCK_ARGUMENT, opName: ""}`.
2. A non-constant-like op, for example, `arith.addi`, is `{type: NON_CONSTANT_OP, opName: "arith.addi"}`.
3. A constant-like op, for example, `arith.constant`, is `{type: CONSTANT_OP, opName: "arith.constant"}`.
So, if an operand, say `A`, was produced as follows:
```
`<block argument>` `<block argument>`
\ /
\ /
`arith.subi` `arith.constant`
\ /
`arith.addi`
|
returns `A`
```
Then, the block arguments and operations present in the backward slice of `A`, in the breadth-first order are:
`arith.addi`, `arith.subi`, `arith.constant`, `<block argument>`, and `<block argument>`.
Thus, the "key" associated with operand `A` is:
```
{
{type: NON_CONSTANT_OP, opName: "arith.addi"},
{type: NON_CONSTANT_OP, opName: "arith.subi"},
{type: CONSTANT_OP, opName: "arith.constant"},
{type: BLOCK_ARGUMENT, opName: ""},
{type: BLOCK_ARGUMENT, opName: ""}
}
```
Now, if "keyA" is the key associated with operand `A` and "keyB" is the key associated with operand `B`, then:
"keyA" < "keyB" iff:
1. In the first unequal pair of corresponding AncestorKeys, the AncestorKey in operand `A` is smaller, or,
2. Both the AncestorKeys in every pair are the same and the size of operand `A`'s "key" is smaller.
AncestorKeys of type `BLOCK_ARGUMENT` are considered the smallest, those of type `CONSTANT_OP`, the largest, and `NON_CONSTANT_OP` types come in between. Within the types `NON_CONSTANT_OP` and `CONSTANT_OP`, the smaller ones are the ones with smaller op names (lexicographically).
---
Some examples of such a sorting:
Assume that the sorting is being applied to `foo.commutative`, which is a commutative op.
Example 1:
> %1 = foo.const 0
> %2 = foo.mul <block argument>, <block argument>
> %3 = foo.commutative %1, %2
Here,
1. The key associated with %1 is:
```
{
{CONSTANT_OP, "foo.const"}
}
```
2. The key associated with %2 is:
```
{
{NON_CONSTANT_OP, "foo.mul"},
{BLOCK_ARGUMENT, ""},
{BLOCK_ARGUMENT, ""}
}
```
The key of %2 < the key of %1
Thus, the sorted `foo.commutative` is:
> %3 = foo.commutative %2, %1
Example 2:
> %1 = foo.const 0
> %2 = foo.mul <block argument>, <block argument>
> %3 = foo.mul %2, %1
> %4 = foo.add %2, %1
> %5 = foo.commutative %1, %2, %3, %4
Here,
1. The key associated with %1 is:
```
{
{CONSTANT_OP, "foo.const"}
}
```
2. The key associated with %2 is:
```
{
{NON_CONSTANT_OP, "foo.mul"},
{BLOCK_ARGUMENT, ""}
}
```
3. The key associated with %3 is:
```
{
{NON_CONSTANT_OP, "foo.mul"},
{NON_CONSTANT_OP, "foo.mul"},
{CONSTANT_OP, "foo.const"},
{BLOCK_ARGUMENT, ""},
{BLOCK_ARGUMENT, ""}
}
```
4. The key associated with %4 is:
```
{
{NON_CONSTANT_OP, "foo.add"},
{NON_CONSTANT_OP, "foo.mul"},
{CONSTANT_OP, "foo.const"},
{BLOCK_ARGUMENT, ""},
{BLOCK_ARGUMENT, ""}
}
```
Thus, the sorted `foo.commutative` is:
> %5 = foo.commutative %4, %3, %2, %1
Signed-off-by: Srishti Srivastava <srishti.srivastava@polymagelabs.com>
Reviewed By: Mogball
Differential Revision: https://reviews.llvm.org/D124750
Integer range inference has been swapped to the new framework. The integer value range lattices automatically updates the corresponding constant value on update.
Depends on D127173
Reviewed By: krzysz00, rriddle
Differential Revision: https://reviews.llvm.org/D128866
This patch introduces a (forward) sparse data-flow analysis implemented with the data-flow analysis framework. The analysis interacts with liveness information that can be provided by dead-code analysis to be conditional. This patch re-implements SCCP using dead-code analysis and (conditional) constant propagation analyses.
Depends on D127064
Reviewed By: rriddle, phisiart
Differential Revision: https://reviews.llvm.org/D127139
Operand's defining op may not be valid for adding to the worklist under
stict mode
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D127180
The constructor already supports passing an ostream as argument,
so let's make the create function support it too.
Differential Revision: https://reviews.llvm.org/D127449
In strict mode, only the new inserted operation is allowed to add to the
worklist. Before this change, it would add the users of a replaced op
and it didn't check if the users are allowed to be pushed into the
worklist
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D126899
The previous fix from af371f9f98 only applied when using a bottom-up
traversal. The change here applies the constant preprocessing logic to the
top-down case as well. This resolves the issue with the canonicalizer pass still
reordering constants, since it uses a top-down traversal by default.
Fixes#51892
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D125623
The canonicalize command-line options currently have no effect, as the pass is
reading the pass options in its constructor, before they're actually
initialized. This results in the default values of the options always being used.
The change here moves the initialization of the `GreedyRewriteConfig` out of the
constructor, so that it runs after the pass options have been parsed.
Fixes#55466
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D125621
This patch adds a topological sort utility and pass. A topological sort reorders
the operations in a block without SSA dominance such that, as much as possible,
users of values come after their producers.
The utility function sorts topologically the operation range in a given block
with an optional user-provided callback that can be used to virtually break cycles.
The toposort pass itself recursively sorts graph regions under the target op.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D125063
This commit refactors the current pass manager support to allow for
operation agnostic pass managers. This allows for a series of passes
to be executed on any viable pass manager root operation, instead
of one specific operation type. Op-agnostic/generic pass managers
only allow for adding op-agnostic passes.
These types of pass managers are extremely useful when constructing
pass pipelines that can apply to many different types of operations,
e.g., the default inliner simplification pipeline. With the advent of
interface/trait passes, this support can be used to define FunctionOpInterface
pass managers, or other pass managers that effectively operate on
specific interfaces/traits/etc (see #52916 for an example).
Differential Revision: https://reviews.llvm.org/D123536
Previously, checking that a fix point is reached was counted as a full
iteration. As this "iteration" never changes the IR, this seems counter-
intuitive.
Differential Revision: https://reviews.llvm.org/D123641