
Fix llvm.ident exploding when linking many bitcode files in libclc. This should de-duplicate other named metadata as well, e.g. opencl.spir.version and opencl.ocl.version. This PR is a re-submit of https://reviews.llvm.org/D20582 (authored by Matt Arsenault) with update that only checks MD node pointer for duplication according to review comment in that PR. --------- Co-authored-by: Matt Arsenault <arsenm2@gmail.com>