llvm.invariant.group.barrier may accept pointers to arbitrary address space.
This patch let it accept pointers to i8 in any address space and returns
pointer to i8 in the same address space.
Differential Revision: https://reviews.llvm.org/D39973
llvm-svn: 318413
`dropUnknownNonDebugMetadata` takes a list of "known" metadata IDs. The
only reason it worked at all is that `getMetadataID` returns something
unrelated -- it returns the subclass ID of the receiver (which is used
in `dyn_cast` etc.). That does not numerically match
`LLVMContext::MD_invariant_group` and ends up dropping `invariant_group`
along with every other metadata that does not numerically match
`LLVMContext::MD_invariant_group`.
llvm-svn: 289973