[llvm-branch-commits] [llvm-objcopy] Support CREL (PR #97521)

[Fangrui Song via llvm-branch-commits]

MaskRay wrote:

> [jh7370](https://github.com/jh7370) I've skimmed briefly and the changes look reasonable - will look more in depth on a separate occasion when I have more time.

Thanks!

> Not for this PR, but I wonder if there would be some benefit in a `--decode-crel` and/or `--encode-crel` option that would convert an object file to/from using CREL. I feel like this might be useful for experimentation, or for handling the case where an object was generated with CREL but needs to be usable by an older tool that doesn't understand CREL. Equally, it could be useful for retroactively encoding CREL when the feature wasn't used during original creation of the object. Thoughts?

Agreed that the `CREL => RELA` conversion will be useful to make CREL better interchange format - allow old linkers to build new relocatable files and allow other tools for analysis tasks.
That is probably a long-term goal.

In the short-term I aim for providing a complete toolchain (assembler,linker,objcopy/strip,objdump) for the most important use case (compile + assemble + (strip)? + link).

> [smithp35](https://github.com/smithp35) Only a couple of small comments from me. I'll be out of the office till Monday next week, I'm fine for others to progress this wihout me.

Thanks! Take your time.


https://github.com/llvm/llvm-project/pull/97521