[llvm] [msan] Add test cases for vector shadow track origins bug (PR #97611)

[Thurston Dang via llvm-commits]

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@@ -0,0 +1,46 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --tool build-release/bin/opt --version 5
+; RUN: opt < %s -S -passes="msan<eager-checks;track-origins=2>" -msan-instrumentation-with-call-threshold=0 -disable-verify | FileCheck %s
+;
+; UNSUPPORTED: target={{.*}}
+;
+; This test illustrates a bug in MemorySanitizer that will shortly be fixed
+; (https://github.com/llvm/llvm-project/pull/96722).
+;
+; '-msan-instrumentation-with-call-threshold=0' makes it possible to detect the
+; bug with a short test case.
+;
+; '-disable-verify' with a release build is needed to avoid a compiler crash
----------------
thurstond wrote:

-disable-verify is necessary to allow autogenerating the assertions in the test.

https://github.com/llvm/llvm-project/pull/97611