[llvm] [BranchFolding][SEH] Add test to track SEH CFG optimization (PR #77598)

[Phoebe Wang via llvm-commits]

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@@ -0,0 +1,49 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 4
+# RUN: llc -mtriple=x86_64-pc-windows-msvc -run-pass=branch-folder -o - %s | FileCheck %s
+---
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phoebewang wrote:

Should attach IR in the test? Besides, without IR, how can we enable async exception?

https://github.com/llvm/llvm-project/pull/77598