[llvm] [RISCV][InsertVSETVLI] Remove redundant vsetvli by repeating the coalesce phase (PR #141298)

[Min-Yih Hsu via llvm-commits]

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mshockwave wrote:

This test was generated by llvm-reduce, but let me see if I can remove some of the blocks...

https://github.com/llvm/llvm-project/pull/141298