[PATCH] D118647: [hwasan] work around lifetime issue with setjmp.

[Florian Mayer via Phabricator via llvm-commits]

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setjmp can return twice, but PostDominatorTree is unaware of this. as
such, it overestimates postdominance, leaving some cases (see attached
compiler-rt) where memory does not get untagged on return. this causes
false positives later in the program execution.

this is a crude workaround to unblock use-after-scope for now, in the
longer term PostDominatorTree should bemade aware of returns_twice
function, as this may cause problems elsewhere.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D118647

Files:
  compiler-rt/test/hwasan/TestCases/use-after-scope-setjmp.cpp
  llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
  llvm/test/Instrumentation/HWAddressSanitizer/use-after-scope-setjmp.ll

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