[llvm] [RISCV] Fix CASE_VFMA_CHANGE_OPCODE_VV to handle MF4 pseudos (PR #88947)

[Craig Topper via llvm-commits]

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@@ -0,0 +1,45 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 4
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topperc wrote:

There should be existing IR tests for this code. They don't test every permutation fore very LMUL, that's why this was missed. I'd prefer updating one of those tests instead of a new MIR test.

https://github.com/llvm/llvm-project/pull/88947