[all-commits] [llvm/llvm-project] 7e4ae2: [Sanitizers] Don't inline unpoisoning of small sta...

[Mariusz Borsa via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 7e4ae28645ef3ad36f1daec3fe3edc901f561bc7
      https://github.com/llvm/llvm-project/commit/7e4ae28645ef3ad36f1daec3fe3edc901f561bc7
  Author: Mariusz Borsa <wrotki at msn.com>
  Date:   2023-12-15 (Fri, 15 Dec 2023)

  Changed paths:
    M llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
    A llvm/test/Instrumentation/AddressSanitizer/calls-only-smallfn.ll
    M llvm/test/Instrumentation/AddressSanitizer/calls-only.ll

  Log Message:
  -----------
  [Sanitizers] Don't inline unpoisoning of small stacks when inlining disabled (#75555)

When ASan.MaxInlinePoisoningSize == 0 , it means that no shadow memory
operations should be made via inlined instrumentation code,
but only via calls to shadow setting functions. This change fixes one
violation of this, which happened when the function allocas count
was small, i.e. less than 5 - in the code modifying the shadow just
before ret instruction.
We now explicitly check ASan.MaxInlinePoisoningSize , and if it's 0 then
we disallow inlining. It is required for the instrumentation
emitting code suitable for handling by ABI implementation.

rdar://119513720

Co-authored-by: Mariusz Borsa <m_borsa at apple.com>