[clang] [Clang] Remove 3-element vector load and store special handling (PR #104661)

[Matt Arsenault via cfe-commits]

================
@@ -123,6 +124,12 @@ class ABIInfo {
                                        raw_ostream &Out) const;
   virtual void appendAttributeMangling(StringRef AttrStr,
                                        raw_ostream &Out) const;
+
+  /// Returns the optimal vector type based on the given vector type. For
+  /// example, on certain targets, a vector with 3 elements might be promoted to
+  /// one with 4 elements to improve performance.
+  virtual llvm::FixedVectorType *
+  getOptimalVectorType(llvm::FixedVectorType *T, const LangOptions &Opt) const;
----------------
arsenm wrote:

should specify it's in in memory type in the name and comment 

https://github.com/llvm/llvm-project/pull/104661