[llvm] [RISCV] Split TuneShiftedZExtFusion (PR #76032)

[Mikhail Gudim via llvm-commits]

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@@ -1,7 +1,7 @@
 # REQUIRES: asserts
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mgudim wrote:

It would be nice to add tests that exercise logic from `checkRegisters`, but we can leave it to a different PR

https://github.com/llvm/llvm-project/pull/76032