[llvm] [SLP] Fix canConvertToFMA operand selection and fmul costing (PR #216425)

[Alexey Bataev via llvm-commits]

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@@ -0,0 +1,130 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
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alexey-bataev wrote:

Precommit the test in separate NFC patch

https://github.com/llvm/llvm-project/pull/216425