[llvm] [LLVM] Make use of s_flbit_i32_b64 and s_ff1_i32_b64 (PR #75158)

[Jay Foad via llvm-commits]

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@@ -0,0 +1,308 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
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jayfoad wrote:

I don't think you need this file. The `.ll` version is simpler and tests the same thing.

https://github.com/llvm/llvm-project/pull/75158