[llvm] [LoopVectorize] Fix nondeterminism in loop-vectorize (PR #200833)

[Orlando Cazalet-Hyams via llvm-commits]

================
@@ -0,0 +1,128 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt --passes=loop-vectorize %s -S | FileCheck %s
+
+; Check that we see expected deterministic (over multiple test runs) output.
+; NOTE: Beware, if this test fails it may be due to non-determinism.
----------------
OCHyams wrote:

Yes it should be completely deterministic with this patch. Perhaps poorly worded - my intention was to signal that if the issue were to be re-introduced somehow then this test would fail intermittently.

https://github.com/llvm/llvm-project/pull/200833