[llvm] [GVN] Reorganise GVN.h/GVH.cpp to improve readability and maintainability (NFC) (PR #210334)

[Momchil Velikov via llvm-commits]

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@@ -120,37 +120,10 @@ struct GVNOptions {
 /// FIXME: We should have a good summary of the GVN algorithm implemented by
 /// this particular pass here.
 class GVNPass : public OptionalPassInfoMixin<GVNPass> {
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momchil-velikov wrote:

One way to do it is https://github.com/llvm/llvm-project/pull/211024 , I guess.
I suppose also it could be `pImpl`ed.


https://github.com/llvm/llvm-project/pull/210334