[llvm] [llvm] Remove `br i1 undef` from regression tests (PR #116161)

[Nuno Lopes via llvm-commits]

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@@ -50,13 +53,13 @@ entry:
   br label %while.cond
 
 while.cond:
-  br i1 undef, label %while.end, label %while.body
+  br i1 %arg, label %while.end, label %while.body
 
 while.body:                                       ; preds = %while.cond
-  br i1 undef, label %if.then165, label %while.cond
+  br i1 %arg, label %if.then165, label %while.cond
 
 if.then165:                                       ; preds = %while.body
-  br i1 undef, label %while.cond, label %for.body.lr.ph.i81
+  br i1 %arg, label %while.cond, label %for.body.lr.ph.i81
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nunoplopes wrote:

infinite loops are only UB if the function is marked as terminating (the `mostprogress` attribute).
By default, Alive2 only unrolls once. It can be changed with a flag.

All that said, it would be be best to have loops that are not infinite.

https://github.com/llvm/llvm-project/pull/116161