[NFC][IR2Vec] Exposing helpers in IR2Vec Vocabulary

Author: svkeerthy

llvm/include/llvm/Analysis/IR2Vec.h

@@ -163,6 +163,14 @@ class Vocabulary {
   static constexpr unsigned MaxOperandKinds =
       static_cast<unsigned>(OperandKind::MaxOperandKind);
 
+public:
+  Vocabulary() = default;
+  Vocabulary(VocabVector &&Vocab);
+
+  bool isValid() const;
+  unsigned getDimension() const;
+  size_t size() const;
+
   /// Helper function to get vocabulary key for a given Opcode
   static StringRef getVocabKeyForOpcode(unsigned Opcode);
 
@@ -175,14 +183,6 @@ class Vocabulary {
   /// Helper function to classify an operand into OperandKind
   static OperandKind getOperandKind(const Value *Op);
 
-public:
-  Vocabulary() = default;
-  Vocabulary(VocabVector &&Vocab);
-
-  bool isValid() const;
-  unsigned getDimension() const;
-  size_t size() const;
-
   /// Accessors to get the embedding for a given entity.
   const ir2vec::Embedding &operator[](unsigned Opcode) const;
   const ir2vec::Embedding &operator[](Type::TypeID TypeId) const;

llvm/lib/Analysis/IR2Vec.cpp

@@ -518,7 +518,8 @@ IR2VecVocabAnalysis::run(Module &M, ModuleAnalysisManager &AM) {
   // Otherwise, try to read from the vocabulary file.
   if (VocabFile.empty()) {
     // FIXME: Use default vocabulary
-    Ctx->emitError("IR2Vec vocabulary file path not specified");
+    Ctx->emitError("IR2Vec vocabulary file path not specified; You may need to "
+                   "set it using --ir2vec-vocab-path");
     return Vocabulary(); // Return invalid result
   }
   if (auto Err = readVocabulary()) {