This replaces the select chain for edge-padding with an scf.if that
performs the memory operation when the index is in bounds and uses the
pad value when it's not. For transfer_write the same mechanism is used,
skipping the store when the index is out of bounds.
The integration test has a bunch of cases of how I believe this should
work.
Differential Revision: https://reviews.llvm.org/D87241
Vector to SCF conversion still had issues due to the interaction with the natural alignment derived by the LLVM data layout. One traditional workaround is to allocate aligned. However, this does not always work for vector sizes that are non-powers of 2.
This revision implements a more portable mechanism where the intermediate allocation is always a memref of elemental vector type. AllocOp is extended to use the natural LLVM DataLayout alignment for non-scalar types, when the alignment is not specified in the first place.
An integration test is added that exercises the transfer to scf.for + scalar lowering with a 5x5 transposition.
Differential Revision: https://reviews.llvm.org/D87150
Added 128 byte alignment to alloc ops created in VectorToSCF pass.
128b alignment was already introduced to this pass but not to all alloc
ops. This commit changes that by adding 128b alignment to the remaining ops.
The point of specifying alignment is to prevent possible memory alignment errors
on weakly tested architectures.
Differential Revision: https://reviews.llvm.org/D86454
If Memref has rank > 1 this pass emits N-1 loops around
TransferRead op and transforms the op itself to 1D read. Since vectors
must have static shape while memrefs don't the pass emits if condition
to prevent out of bounds accesses in case some memref dimension is smaller
than the corresponding dimension of targeted vector. This logic is fine
but authors forgot to apply `permutation_map` on loops upper bounds and
thus if condition compares induction variable to incorrect loop upper bound
(dimension of the memref) in case `permutation_map` is not identity map.
This commit aims to fix that.
Summary: The logic was conservative but inverted: cases that should remain unmasked became 1-D masked.
Differential Revision: https://reviews.llvm.org/D84051
scf.if currently lacks folding on true / false conditionals.
Such foldings are a bit more involved than can be addressed immediately.
This revision introduces an eager folding for lowering vector.transfer operations in the presence of unrolling.
Differential revision: https://reviews.llvm.org/D83146
This option avoids to accidentally reuse variable across -LABEL match,
it can be explicitly opted-in by prefixing the variable name with $
Differential Revision: https://reviews.llvm.org/D81531
Allow for dynamic indices in the `dim` operation.
Rather than an attribute, the index is now an operand of type `index`.
This allows to apply the operation to dynamically ranked tensors.
The correct lowering of dynamic indices remains to be implemented.
Differential Revision: https://reviews.llvm.org/D81551
Recently introduced allocation hoisting is quite conservative on the cases when it triggers.
This revision makes it such that the allocations for vector transfer lowerings are hoisted
to the top of the function.
This should be revisited in the context of parallelism and is a temporary workaround.
Differential Revision: https://reviews.llvm.org/D81253
https://reviews.llvm.org/D79246 introduces alignment propagation for vector transfer operations. Unfortunately, the alignment calculation is incorrect and can result in crashes.
This revision fixes the calculation by using the natural alignment of the memref elemental type, instead of the resulting vector type.
If more alignment is desired, it can be done in 2 ways:
1. use a proper vector.type_cast to transform a memref<axbxcxdxf32> into a memref<axbxvector<cxdxf32>> giving a natural alignment of vector<cxdxf32>
2. add an alignment attribute to vector transfer operations and propagate it.
With this change the alignment in the relevant tests goes down from 128 to 4.
Lastly, a few minor cleanups are performed and the custom `isMinorIdentityMap` is deprecated.
Differential Revision: https://reviews.llvm.org/D80734
Summary:
Previously, the only support partial lowering from vector transfers to SCF was
going through loops. This requires a dedicated allocation and extra memory
roundtrips because LLVM aggregates cannot be indexed dynamically (for more
details see the [deep-dive](https://mlir.llvm.org/docs/Dialects/Vector/#deeperdive)).
This revision allows specifying full unrolling which removes this additional roundtrip.
This should be used carefully though because full unrolling will spill, negating the
benefits of removing the interim alloc in the first place.
Proper heuristics are left for a later time.
Differential Revision: https://reviews.llvm.org/D80100
