[PATCH] D44511: [MSan] Introduce ActualFnStart. NFC

[Alexander Potapenko via Phabricator via llvm-commits]

glider added a comment.

This basic block will contain a runtime call, which provides addresses of TLS structs used later in the instrumentation.
If we insert the call late, we'll have to fix all the users of its return values, which is trickier than inserting the call in advance.


Repository:
  rL LLVM

https://reviews.llvm.org/D44511