[llvm] [IR2Vec] Exposing Embedding as an ADT wrapped around std::vector<double> (PR #143197)

[Mircea Trofin via llvm-commits]

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@@ -53,7 +53,24 @@ class raw_ostream;
 enum class IR2VecKind { Symbolic };
 
 namespace ir2vec {
-using Embedding = std::vector<double>;
+/// Embedding is a ADT that wraps std::vector<double>. It provides
+/// additional functionality for arithmetic and comparison operations.
+struct Embedding : public std::vector<double> {
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mtrofin wrote:

which APIs do you actually need?

composition gives us more decoupling wrt underlying data structure. With an explicit constructor, you could control a to-from treatment of vectors (including llvm ADTs, potentially) as Embeddings. The delegation of curated APIs to the underlying data structure doesn't seem that big of a problem. 

ack that there are uses, not convinced they are necessarily an expression of best practices.

https://github.com/llvm/llvm-project/pull/143197