[llvm] [RISCV][GlobalISel] Legalize scalable vectorized G_ADD, G_SUB, G_AND, G_OR, and G_XOR (PR #71400)

[Kito Cheng via llvm-commits]

kito-cheng wrote:

PR description means your first comment, e.g.
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Hi,

I'm excited to ...
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https://github.com/llvm/llvm-project/pull/71400