[libc-commits] [libc] [libc][arm] implement a basic setjmp/longjmp (PR #93220)

[Peter Smith via libc-commits]

smithp35 wrote:

Apologies for the delay in responding, yes Thumb 1 only is important. There is also armv8-m.base (cortex-m23) which is the Arm v8 version of Thumb 1 only v6-m.

I've asked our C-library expert if he can take a look at the Arm specific details.

The main problem LLVM-libc will have v6-m is that it doesn't have any load/store exclusive instructions so it is unsuitable for multithreaded implementations. Strictly speaking interrupts can be disabled, but this is a privileged instruction.

https://github.com/llvm/llvm-project/pull/93220