This PR relaxes the 2d reduction lowering in the peephole optimization
pass to allow source tensor to have n-d shape.
It also fixes a minor bug of accumulator lowering in the current
implementation.
Some XeGPU transforms can generate code sequences that can simplified by
folding. But full canonicalization is not required. As an alternative,
remove canonicalize from some parts of the pipeline where only folding
is needed and add folding at the end of XeGPU blocking pass
and XeGPU peephole optimize pass.
This PR refactors layout propagation into two distinct components:
result/anchor layout setup and source layout inference from the result.
For operations that require a specific result layout due to semantic or
hardware constraints, the propagation logic explicitly sets up the
result or anchor layout. Otherwise, it infers the source layout from the
backward-propagated consumer layout.
The result or anchor layout may differ from the backward-propagated
consumer layout; any such discrepancies are resolved via the existing
layout-conflict mechanism.
**This PR introduces the following utility functions:**
Source layout inference:
> inferBroadcastSourceLayout()
> inferMultiReductionSourceLayout()
> inferBitCastSourceLayout()
> inferShapeCastSourceLayout()
> inferInsertStridedSliceSourceLayout()
Result / anchor layout setup:
> setupMultiReductionResultLayout()
> setupBitCastResultLayout()
> setupInsertStridedSliceResultLayout()
> setupLoadMatrixAnchorLayout()
> setupStoreMatrixAnchorLayout()
> setupLoadGatherAnchorLayout()
> setupStoreScatterAnchorLayout()
Part of subgroup distribution related code changes are separated and
created as PR https://github.com/llvm/llvm-project/pull/179018/changes.
