[llvm] [ConstraintElim] Add missing check to make sure the bound is loop-invariant (PR #70555)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,94 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt -passes=constraint-elimination -S %s | FileCheck %s
+
+define i32 @main() {
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fhahn wrote:

nit: might be good to make the test name more explicit, e.g. test_loop_varying_bound_add_rec

https://github.com/llvm/llvm-project/pull/70555