[compiler-rt] [llvm] [TySan] Add option to outline instrumentation (PR #120582)

[via llvm-commits]

gbMattN wrote:

> Might be a crazy idea, but would it make sense to add a mode where we emit both the inline and outlined versions and check if they agree? Would be even slower but might be a good way to verify both implementations agree?

As in emit an executable with both inline IR and function calls and make sure the result of each is the same? It would make testing easier for sure, but I'd be worried about the increase in complexity that could cause

> Also, is there a reason this is still a draft?

Ah, I think I did that by accident, I'll change that!

W.R.T where this pull request is:
 There is a bug when doing the basic.c test in outlined mode; the error is incorrectly reported as coming from `__tysan_instrument_with_shadow_update` rather than `main`, and I haven't made a compiler-rt test(s) specifically for outlining. 

https://github.com/llvm/llvm-project/pull/120582