[llvm] [BranchFolder] Fix missing debug info with tail merging (PR #94715)

[Jeremy Morse via llvm-commits]

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@@ -0,0 +1,31 @@
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -enable-tail-merge=1 -stop-after=branch-folder | FileCheck %s
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jmorse wrote:

Given that this patch is affecting only branch folding, it makes sense to have the test only cover the branch folding pass -- if you run llc with `-stop-before=branch-folder` you'll get some MIR output, which you can then apply a single pass to by giving llc the `--run-pass=branch-folder`. (Benefits: the test won't be affected by earlier passes, and people reading the test will see the direct input to the branch-folder pass).

https://github.com/llvm/llvm-project/pull/94715