We have a pass for MVE to perform lane interleaving to make use of top/bottom
instructions, that adds shuffles before extends and after truncates. This
extends it to also start from add reductions, where the order of lanes does not
matter so the shuffle is not needed. We need to be careful about not breaking
the form of existing reductions, but otherwise can save some instructions and
awkward extends.
Differential Revision: https://reviews.llvm.org/D143396
Add a number of intrinsics which natively lower to MVE operations to the
lane interleaving pass, allowing it to efficiently interleave the lanes
of chucks of operations containing these intrinsics.
Differential Revision: https://reviews.llvm.org/D97293
FP16 to FP32 converts can be handled in MVE lane interleaving, much like
the sext/zext lowering we do. This expands the pass with fpext and
fptrunc handling, and basic fp operations allowing more efficient
lowering of fp vectors.
Differential Revision: https://reviews.llvm.org/D97292
As another addition to MVE lane interleaving, this handles Splat shuffle
vectors, as the shuffle of a splat is a splat.
Differential Revision: https://reviews.llvm.org/D97291
This extends the recent MVE lane interleaving passto handle other
non-instruction leaves, for which a new shuffle is added. This helps
especially for constants and potentially for arguments.
Differential Revision: https://reviews.llvm.org/D97289
MVE does not have a single sext/zext or trunc instruction that takes the
bottom half of a vector and extends to a full width, like NEON has with
MOVL. Instead it is expected that this happens through top/bottom
instructions. So the MVE equivalent VMOVLT/B instructions take either
the even or odd elements of the input and extend them to the larger
type, producing a vector with half the number of elements each of double
the bitwidth. As there is no simple instruction for a normal extend, we
often have to expand sext/zext/trunc into a series of lane moves (or
stack loads/stores, which we do not do yet).
This pass takes vector code that starts at truncs, looks for
interconnected blobs of operations that end with sext/zext and
transforms them by adding shuffles so that the lanes are interleaved and
the MVE VMOVL/VMOVN instructions can be used. This is done pre-ISel so
that it can work across basic blocks.
This initial version of the pass just handles a limited set of
instructions, not handling constants or splats or FP, which can all come
as extensions to this base.
Differential Revision: https://reviews.llvm.org/D95804