[llvm] [LV] Teach the loop vectorizer llvm.sincos is trivially vectorizable (PR #128035)

[Benjamin Maxwell via llvm-commits]

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@@ -0,0 +1,170 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --filter "(:|sincos|extractvalue|store)" --version 5
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MacDue wrote:

(the `update_test_checks.py` script automatically applies the arguments from the `UTC_ARGS:` section) 

https://github.com/llvm/llvm-project/pull/128035