[llvm] [llvm] Remove `br i1 undef` in `llvm/test/CodeGen` tests (PR #127368)

[David Green via llvm-commits]

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@@ -7,9 +7,9 @@ target triple = "arm64-apple-ios"
 
 declare void @bar(ptr)
 
-define void @foo(ptr %m, i32 %off0) {
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davemgreen wrote:

This says `; Make sure we don't end up with a CBNZ of an undef v-/phys-reg`, which this is no longer testing. (It didn't have any check lines before though, I assume it was guarding against an assert/crash). 

Using `poison` is maybe better here.

https://github.com/llvm/llvm-project/pull/127368