The LD/STD likewise instruction are selected only when the alignment in
the load/store >= 4 to deal with the case that the offset might not be
known(i.e. relocations). That means we have to select the X-Form load
for %0 = load i64, i64* %arrayidx, align 2 In fact, we can still select
the D-Form load if the offset is known. So, we only query the load/store
alignment when we don't know if the offset is a multiple of 4.
Reviewed By: jji, Nemanjai
Differential Revision: https://reviews.llvm.org/D93099
As reported in PR45186, we could be in a situation where we don't
want to handle unaligned memory accesses for FP scalars but still
have VSX (which allows unaligned access for vectors). Change the
default to only apply to scalars.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=45186
QingShan Zhang