[llvm] [RISCV] Separate the analysis part of RISCVInsertVSETVLI. (PR #149574)

[Pengcheng Wang via llvm-commits]

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@@ -65,6 +65,7 @@ add_llvm_target(RISCVCodeGen
   RISCVTargetMachine.cpp
   RISCVTargetObjectFile.cpp
   RISCVTargetTransformInfo.cpp
+  RISCVVConfigAnalysis.cpp
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wangpc-pp wrote:

I don't know if this is the best name, because when I saw it, I just wondered "what is the Config?" because I ignored the "V". I don't have a better name, maybe we can just use `RISCVVTypeAnalysis`?

https://github.com/llvm/llvm-project/pull/149574