[llvm] [Debuginfo][TailCallElim] Fix #86262: drop the debug location of entry branch (PR #86269)

[Stephen Tozer via llvm-commits]

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@@ -0,0 +1,57 @@
+; RUN: opt -S -passes=tailcallelim < %s | FileCheck %s
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SLTozer wrote:

One more thing, it'd be good to add a comment describing what this is testing for, particularly since the CHECK lines are fairly bare. Related to that, does this test add any coverage that the previous test (`debugloc.ll`) doesn't cover?

https://github.com/llvm/llvm-project/pull/86269