[llvm] [Sanitizer] Make sanitizer passes idempotent (PR #99439)

[via llvm-commits]

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@@ -0,0 +1,56 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals all --version 5
+; This test checks in the second run, function is not instrumented again.
+; RUN: opt < %s -passes=asan,asan -S | FileCheck %s
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b-sumner wrote:

Instrumenting a shadow load practically guarantees an immediate memory fault or other catastrophic behavior.  I assume any optimization passes that could cause such trouble are already idempotent.

https://github.com/llvm/llvm-project/pull/99439