[lld] [llvm] [llvm-objdump][ARM] Find ELF file PLT entries for arm, thumb (PR #130764)

[Vladislav Dzhidzhoev via llvm-commits]

dzhidzhoev wrote:

> > I'm not a great fan of the big binary blobs in the llvm-objdump tests. I wonder if it would be more appropriate for these tests to appear in `cross-project-tests`, where they could use both lld and llvm-objdump, since they are testing llvm-objdump's behaviour in conjunction with LLD's PLT generation behaviour. Thoughts @MaskRay?
> > Another slightly wacky idea could be to write the instructions in assembly, use llvm-mc to generate an object file containing the corresponding sections (with pre-computed values for addresses, where needed), then use llvm-objcopy to extract those sections into files that are somehow read and passed as the -D parameter values to yaml2obj. That's probably too much setup to be worthwhile, but just throwing it out there as an option.
> 
> Adding `clang --target=armSUFFIX` -fuse-ld=lld tests to `cross-project-tests` seems like a good approach. We can perhaps create `cross-project-tests/tools/llvm-objdump/ARM`.
> 
> While cross-project-tests might not be the primary focus for all developers, we still have lld/test/ELF tests for the behavior.

Done

https://github.com/llvm/llvm-project/pull/130764