Commit Graph

8 Commits

Author SHA1 Message Date
Aart Bik
0b1764a3d7 [mlir][sparse] sparse tensor storage implementation
This revision connects the generated sparse code with an actual
sparse storage scheme, which can be initialized from a test file.
Lacking a first-class citizen SparseTensor type (with buffer),
the storage is hidden behind an opaque pointer with some "glue"
to bring the pointer back to tensor land. Rather than generating
sparse setup code for each different annotated tensor (viz. the
"pack" methods in TACO), a single "one-size-fits-all" implementation
has been added to the runtime support library.  Many details and
abstractions need to be refined in the future, but this revision
allows full end-to-end integration testing and performance
benchmarking (with on one end, an annotated Lingalg
op and, on the other end, a JIT/AOT executable).

Reviewed By: nicolasvasilache, bixia

Differential Revision: https://reviews.llvm.org/D95847
2021-02-10 11:57:24 -08:00
River Riddle
e21adfa32d [mlir] Mark LogicalResult as LLVM_NODISCARD
This makes ignoring a result explicit by the user, and helps to prevent accidental errors with dropped results. Marking LogicalResult as no discard was always the intention from the beginning, but got lost along the way.

Differential Revision: https://reviews.llvm.org/D95841
2021-02-04 15:10:10 -08:00
Aart Bik
b5c542d64b [mlir][sparse] add narrower choices for pointers/indices
Use cases with 16- or even 8-bit pointer/index structures have been identified.

Reviewed By: penpornk

Differential Revision: https://reviews.llvm.org/D95015
2021-01-19 20:20:38 -08:00
Aart Bik
f4f158b2f8 [mlir][sparse] add vectorization strategies to sparse compiler
Similar to the parallelization strategies, the vectorization strategies
provide control on what loops should be vectorize. Unlike the parallel
strategies, only innermost loops are considered, but including reductions,
with the control of vectorizing dense loops only or dense and sparse loops.

The vectorized loops are always controlled by a vector mask to avoid
overrunning the iterations, but subsequent vector operation folding removes
redundant masks and replaces the operations with more efficient counterparts.
Similarly, we will rely on subsequent loop optimizations to further optimize
masking, e.g. using an unconditional full vector loop and scalar cleanup loop.

The current strategy already demonstrates a nice interaction between the
sparse compiler and all prior optimizations that went into the vector dialect.

Ongoing discussion at:
https://llvm.discourse.group/t/mlir-support-for-sparse-tensors/2020/10

Reviewed By: penpornk

Differential Revision: https://reviews.llvm.org/D94551
2021-01-13 11:55:23 -08:00
Kazuaki Ishizaki
2b638ed5a1 [mlir] NFC: fix trivial typos
fix typos under docs, test, and tools directories

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D94158
2021-01-07 02:36:02 +09:00
Aart Bik
d5f0d0c0c4 [mlir][sparse] add ability to select pointer/index storage type
This change gives sparse compiler clients more control over selecting
individual types for the pointers and indices in the sparse storage schemes.
Narrower width obviously results in smaller memory footprints, but the
range should always suffice for the maximum number of entries or index value.

Reviewed By: penpornk

Differential Revision: https://reviews.llvm.org/D92126
2020-11-25 17:32:44 -08:00
Aart Bik
5c4e397e6c [mlir][sparse] add parallelization strategies to sparse compiler
This CL adds the ability to request different parallelization strategies
for the generate code. Every "parallel" loop is a candidate, and converted
to a parallel op if it is an actual for-loop (not a while) and the strategy
allows dense/sparse outer/inner parallelization.

This will connect directly with the work of @ezhulenev on parallel loops.

Still TBD: vectorization strategy

Reviewed By: penpornk

Differential Revision: https://reviews.llvm.org/D91978
2020-11-24 17:17:13 -08:00
Aart Bik
eced4a8e6f [mlir] [sparse] start of sparse tensor compiler support
As discussed in https://llvm.discourse.group/t/mlir-support-for-sparse-tensors/2020
this CL is the start of sparse tensor compiler support in MLIR. Starting with a
"dense" kernel expressed in the Linalg dialect together with per-dimension
sparsity annotations on the tensors, the compiler automatically lowers the
kernel to sparse code using the methods described in Fredrik Kjolstad's thesis.

Many details are still TBD. For example, the sparse "bufferization" is purely
done locally since we don't have a global solution for propagating sparsity
yet. Furthermore, code to input and output the sparse tensors is missing.
Nevertheless, with some hand modifications, the generated MLIR can be
easily converted into runnable code already.

Reviewed By: nicolasvasilache, ftynse

Differential Revision: https://reviews.llvm.org/D90994
2020-11-17 13:10:42 -08:00