[clang] [compiler-rt] [compiler-rt] Realtime Sanitizer: Introduce Realtime Sanitizer (RTSan) backend (PR #92460)

[Chris Apple via llvm-commits]

cjappl wrote:

Pinging reviewers, after we had more conversations on the overall structure and usefulness of RTSan, and it was approved. 

@zygoloid @vitalybuka @MaskRay 

Details of the aforementioned discussion are around here in the discourse thread:
https://discourse.llvm.org/t/rfc-nolock-and-noalloc-attributes/76837/82

https://github.com/llvm/llvm-project/pull/92460