[llvm] [MSan] Fix va_arg handling on 32-bit machines (PR #211339)

[Vitaly Buka via llvm-commits]

vitalybuka wrote:

If we do this, we need to split into stacked PR.

1. NFC patch: Extract VarArgStackModelHelperBase to deduplicate finalizeInstrumentation() between VarArgI386Helper and VarArgGenericHelper (and VarArgPowerPC64Helper has the exact same finalizeInstrumentation() too).

2. One PR per platform/ABI after that

I suspect you can't do realy stacked PRs without commit access, so you will have to sent patches 1 by 1.



https://github.com/llvm/llvm-project/pull/211339