[llvm] Refactoring llvm-ir2vec.cpp for better separation of concerns in the Tooling classes (PR #170078)

[S. VenkataKeerthy via llvm-commits]

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@@ -151,6 +152,29 @@ static cl::opt<EmbeddingLevel>
           cl::init(FunctionLevel), cl::sub(EmbeddingsSubCmd),
           cl::cat(CommonCategory));
 
+/// Entity mappings: [entity_name]
+using EntityList = std::vector<std::string>;
+
+/// Basic block embeddings: [{bb_name, Embedding}]
+using BBVecList = std::vector<std::pair<std::string, ir2vec::Embedding>>;
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svkeerthy wrote:

Why use `string` and not `const BasicBlock*`?

https://github.com/llvm/llvm-project/pull/170078