After D98856 these tests will by default break (fatal_error) if any of
the wrong interfaces are used, so there's no longer a need to have a
RUN line that checks for a warning message emitted by the compiler.
The following operations have no associated cost for them
when applied to scalable vectors, and as a consequence
can trigger a crash when a call is made to
AArch64TTIImpl::getCastInstrCost():
- fptrunc
- trunc
- fpext
- fpto(u,s)i
This patch adds costs for these operations and
relevant regression tests.
Differential Revision: https://reviews.llvm.org/D98934