In XeGPUPropagateLayout.cpp, the helper getDefaultSIMTLayoutInfo is
implemented via multiple overloads that differ significantly in
semantics, not just parameter types.
Reusing the same function name for these semantically different
behaviors makes call sites harder to read and reason about and increases
the maintenance burden. This PR improves readability and maintainability
of layout propagation logic.
Add visitNonControlFlowArgumentst API to SparseBackwardDataFlowAnalysis,
current SparseBackwardDataflowAnalysis cannot access all SSA values,
such as, the loop's IV. Now we can use visitNonControlFlowArgumentst to
visit it. Apply it in LivenessAnalysis/RemoveDeadValues, solved the
issue of IV liveness in the loop.
https://discourse.llvm.org/t/rfc-add-visitbranchregionargument-interface-to-sparsedataflowanalysis/89061
Add a helper function to compute a mapping of successor operands to
successor inputs. This mapping is computed in various places. Also add a
helper function to gather all region branch points.
This commit is in preparation of a bug fix / partial redesign of
`-remove-dead-values`. This commit also removes some duplicate code in
various places.
This PR builds on the anchor layout mechanism introduced in
https://github.com/llvm/llvm-project/pull/169267 and performs the
following refactoring:
1. Introduce getAnchorLayout() and setAnchorLayout() interface for
anchor ops to get and set layout attributes.
2. Add getLocalLayout() and setLocalLayout() utility functions, and
refactor workgroup/subgroup distribution patterns to use these APIs.
These utilities access the layout information directly and locally,
without relying on global propagation.
3. Introduce localPropagateLayoutsFromAnchor(), a utility used by
subgroup distribution to unify non-anchor layout setup.
This function is intended to be invoked upfront by all layout-based
passes (including workgroup/subgroup distribution and unrolling) to
propagate layouts from anchor ops to non-anchor ops.
After this step, patterns within the pass should exclusively use
getLocalLayout() / setLocalLayout().
4. Refactor getDistributeLayoutAttr() and setDistributeLayoutAttr() to
remove special-case handling. These APIs now operate in a uniform order:
anchor ops first, then non-anchor ops, and finally block arguments.
These APIs will be deprecated on long run.
5. Refactor patterns in wg/sg distribution, load optimization passes to
use get/setAnchorLayout() and get/setLocalLayout().
6. Update test cases to enforce that anchor ops must use—and only
use—anchor layouts.
Add special-case handling for ShapeCast when it expands unit dimensions
for a succeeding broadcast op. In this scenario, distribution requires
the source layout to be a slice layout, and the result layout is first
normalized by setting the expanded unit dimensions to 1 before computing
the distributed result shape. In all other cases, ShapeCast is
distributed as usual.
This PR also updates the propagation rule for vectors with expanded unit
dimensions, allowing them to share the same layout as the result of a
broadcast op. This enables correct layout propagation back to the source
of the ShapeCast op, as that layout must ultimately be restored as the
parent layout of the slice layout.
This PR extends XeGPU layout propagation and distribution for
vector.broadcast operation.
It relaxes the restriction of layout propagation to allow low-rank and
scalar source input, and adds a pattern in sg-to-wi distribution to
support the lowering.
Introduce anchor layout for XeGPU anchor ops: load_nd, store_nd,
prefetch_nd, dpas, load, store, prefetch, load_matrix, store_matrix, and
atomic_rmw. Anchor layout is permanent, and is guaranteed to be honored
by XeGPU distribution and lowerinngs once specified.
1. Add anchor_layout for XeGPU anchor OPs: load_nd, store_nd,
prefetch_nd, dpas, load, store, prefetch, load_matrix, store_matrix, and
atomic_rmw.
2. rename layout attributes to anchor_layout for these ops: load, store,
load_matrix, store_matrix
3. update layout propagation pass: Only when user doesn't specify anchor
layout, the pass computes a default layout and set to anchor op's
permant layout and use that for propagation. if user specified anchor
layout, the pass takes user-specified anchor layout. permant layout and
use that for propagation. if user specified anchor layout, the pass
takes user-specified anchor layout.
This pass rewrites certain xegpu `CreateNd` and `LoadNd` operations that
feeds into `vector.transpose` to more optimal form to improve
performance. Specifically, low precision (bitwidth < 32) `LoadNd` ops
that feeds into transpose ops are rewritten to i32 loads with a valid
transpose layout such that later passes can use the load with transpose
HW feature to accelerate such load ops.
**Update:**
Pass is renamed to `OptimizeBlockLoads ` because later we plan to add
the array length optimization into this pass as well. This will break
down a larger load (like `32x32xf16`) into more DPAS-favorable array
length loads (`32x16xf16` with array length = 2). Both these
optmizations require rewriting `CreateNd` and `LoadNd` and it makes
sense to have a common pass for both.
As [suggested
here](https://github.com/llvm/llvm-project/pull/163071#discussion_r2427229637)
the PR adds an optional layout attribute for `LoadGather` and
`StoreScatter` ops.
For the load-op the attribute describes the layout of the result (ex
`layout_result_0`), and for store-op it describes the layout for the
vector-to-store operand (ex `layout_operand_0`).
The PR also reworks `propagate-layout` pass to consider perm layout
attributes and back-propagate them accordingly.
The helper utility function `getDistributeLayoutAttr` is reworked to
return either `layout_operand/result_0` or `layout` for load/store ops
(denepding on which one is set). After an offline discussion decided
that the overall utilities layouts API is confusing since it tries to
mix permament and temporary layouts. Would need to change it in the
future.
---------
Signed-off-by: dchigarev <dmitry.chigarev@intel.com>
This PR adds the features needed for supporting the GEMM with transpose
B case.
Summary of changes.
1). Add distribution logic for `vector.bitcast`, `vector.transpose` and
`memref.extract_aligned_pointer_as_index` cases.
2). Add layout propagation support for `vector.shape_cast`,
`vector.broadcast` and `vector.bitcast`
3). Incorporate slice attribute and `DistributeLayoutAttr` interface
with the core logic in layout prop.
This PR is a reapply of
https://github.com/llvm/llvm-project/pull/154949, which failed one of
sanitizer checks.
The issue was querying the `warpOp` results in `LoadDistribution` after
calling `moveRegionToNewWarpOpAndAppendReturns()`, which resulted in use
after free. This PR solves the issue by moving the op query before the
call and is otherwise identical to the one linked above.
---------
Co-authored-by: Charitha Saumya <136391709+charithaintc@users.noreply.github.com>
This PR adds distribution patterns for scattered load and store ops,
chunk size included.
XeGPU moves toward offsets being part of the load/store ops, so the pass
only supports this case. Manipulating a vector of offsets indirectly
through create_tdesc is complex and soon to become obsolete anyway.
This PR assumes the SIMT-adapted scatter ops verification introduced in
https://github.com/llvm/llvm-project/pull/154653. The distribution
itself can be reviewed in the meantime.
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.
Changes:
* Decouple layout propagation from subgroup distribution and move it to
an independent pass.
* Refine layout assignment to handle control-flow ops correctly (scf.for, scf.while).
* Refine test cases.
