[llvm] [IR] Relax convergence requirements on call (PR #135794)

[Nathan Gauër via llvm-commits]

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@@ -0,0 +1,92 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt %s -passes=adce -S | FileCheck %s
+
+; CHECK:      Function Attrs: convergent
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Keenuts wrote:

They don't directly relate to the verifer, but as convergence removal was not tested for those, I wanted to add those in the same context as a indication for the future person looking at this:
 - why is convergence allowed to remove tokens in DCE as this could link to a convergence mismatch if attribute is dropped with the caller/callee?
 - oh, the commit also relaxed this requirement in the verifier, that's an expected chain of events that was known at the time and accounted for.
 
 But I can split this out of this PR if you want.
 

https://github.com/llvm/llvm-project/pull/135794