[llvm] [msan] Add experimental '-msan-or-shadow-for-strict-instructions' flag to pessimize output (PR #128036)

[Thurston Dang via llvm-commits]

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@@ -0,0 +1,54 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt < %s -passes=msan -S                                         | FileCheck %s --check-prefixes=CLEAN
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thurstond wrote:

It is difficult to find a generic instruction that is handled by visitInstruction. That would imply a cross-platform gap in MSan's instrumentation that should probably be fixed :-). (The LLVM starship operator <=> was one such case, but I fixed it recently in https://github.com/llvm/llvm-project/pull/125804).

https://github.com/llvm/llvm-project/pull/128036