RVV vectors must be aligned to their element types, so anything less is
unaligned.
For regular loads and stores, our custom-lowering of fixed-length
vectors meant that we opted out of LegalizeDAG's built-in unaligned
expansion. This patch adds that logic in to our custom lower function.
For masked intrinsics, we declare that anything unaligned is not legal,
leaving the ScalarizeMaskedMemIntrin pass to do the expansion for us.
Note that neither of these methods can handle the expansion of
scalable-vector memory ops, so those cases are left alone by this patch.
Scalable loads and stores already go through expansion by default but
hit an assertion, and scalable masked intrinsics will silently generate
incorrect code. It may be prudent to return an error in both of these
cases.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D102493
getMinRVVVectorSizeInBits() asserts if the V extension isn't
enabled. So check that gather/scatter is legal first since it
already contains a check for V extension being enabled. It
also already checks getMinRVVVectorSizeInBits for fixed length
vectors so we don't need a check in getGatherScatterOpCost.
The generic cost of logical or/and reductions should be cost of bitcast
<ReduxWidth x i1> to iReduxWidth + cmp eq|ne iReduxWidth.
Differential Revision: https://reviews.llvm.org/D97961
This is a patch that updates the cost of `select i1 a, b, false` to be equivalent to that of `and i1 a, b`
as well as the cost of `select i1 a, true, b` equivalent to `or i1 a, b`.
Until now, these selects were folded into and/or i1 by InstCombine, but the transformation is poison-unsafe.
This is a step towards removing the unsafe transformation. D93065 has relevant transformations linked.
These selects should be translated into the assemblies as and/or i1 do in the same manner. The cost should be equivalent.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D97360
Have BasicTTI call the base implementation so that both agree on the
default behaviour, which the default being a cost of '1'. This has
required an X86 specific implementation as it seems to be very
reliant on those instructions being free. Changes are also made to
AMDGPU so that their implementations distinguish between cost kinds,
so that the unrolling isn't affected. PowerPC also has its own
implementation to prevent changes to the reg-usage vectorizer test.
The cost model test changes now reflect that ret instructions are not
generally free.
Differential Revision: https://reviews.llvm.org/D79164