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diff --git a/llvm/lib/CodeGen/MIR2Vec.cpp b/llvm/lib/CodeGen/MIR2Vec.cpp
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+++ b/llvm/lib/CodeGen/MIR2Vec.cpp
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+//===- MIR2Vec.cpp - Implementation of MIR2Vec ---------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM
+// Exceptions. See the LICENSE file for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file implements the MIR2Vec algorithm for Machine IR embeddings.
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MIR2Vec.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/TargetInstrInfo.h"
+#include "llvm/IR/Module.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/Errc.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Regex.h"
+
+using namespace llvm;
+using namespace mir2vec;
+
+#define DEBUG_TYPE "mir2vec"
+
+STATISTIC(MIRVocabMissCounter,
+          "Number of lookups to MIR entities not present in the vocabulary");
+
+namespace llvm {
+namespace mir2vec {
+cl::OptionCategory MIR2VecCategory("MIR2Vec Options");
+
+// FIXME: Use a default vocab when not specified
+static cl::opt<std::string>
+    VocabFile("mir2vec-vocab-path", cl::Optional,
+              cl::desc("Path to the vocabulary file for MIR2Vec"), cl::init(""),
+              cl::cat(MIR2VecCategory));
+cl::opt<float> OpcWeight("mir2vec-opc-weight", cl::Optional, cl::init(1.0),
+                         cl::desc("Weight for machine opcode embeddings"),
+                         cl::cat(MIR2VecCategory));
+} // namespace mir2vec
+} // namespace llvm
+
+//===----------------------------------------------------------------------===//
+// Vocabulary Implementation
+//===----------------------------------------------------------------------===//
+
+MIRVocabulary::MIRVocabulary(VocabMap &&OpcodeEntries,
+                             const TargetInstrInfo *TII)
+    : TII(*TII) {
+  // Fixme: Use static factory methods for creating vocabularies instead of
+  // public constructors
+  // Early return for invalid inputs - creates empty/invalid vocabulary
+  if (!TII || OpcodeEntries.empty())
+    return;
+
+  buildCanonicalOpcodeMapping();
+
+  unsigned CanonicalOpcodeCount = UniqueBaseOpcodeNames.size();
+  assert(CanonicalOpcodeCount > 0 &&
+         "No canonical opcodes found for target - invalid vocabulary");
+  Layout.OperandBase = CanonicalOpcodeCount;
+  generateStorage(OpcodeEntries);
+  Layout.TotalEntries = Storage.size();
+}
+
+std::string MIRVocabulary::extractBaseOpcodeName(StringRef InstrName) {
+  // Extract base instruction name using regex to capture letters and
+  // underscores Examples: "ADD32rr" -> "ADD", "ARITH_FENCE" -> "ARITH_FENCE"
+  //
+  // TODO: Consider more sophisticated extraction:
+  // - Handle complex prefixes like "AVX1_SETALLONES" correctly (Currently, it
+  // would naively map to "AVX")
+  // - Extract width suffixes (8,16,32,64) as separate features
+  // - Capture addressing mode suffixes (r,i,m,ri,etc.) for better analysis
+  // (Currently, instances like "MOV32mi" map to "MOV", but "ADDPDrr" would map
+  // to "ADDPDrr")
+
+  assert(!InstrName.empty() && "Instruction name should not be empty");
+
+  // Use regex to extract initial sequence of letters and underscores
+  static const Regex BaseOpcodeRegex("([a-zA-Z_]+)");
+  SmallVector<StringRef, 2> Matches;
+
+  if (BaseOpcodeRegex.match(InstrName, &Matches) && Matches.size() > 1) {
+    StringRef Match = Matches[1];
+    // Trim trailing underscores
+    while (!Match.empty() && Match.back() == '_')
+      Match = Match.drop_back();
+    return Match.str();
+  }
+
+  // Fallback to original name if no pattern matches
+  return InstrName.str();
+}
+
+unsigned MIRVocabulary::getCanonicalIndexForBaseName(StringRef BaseName) const {
+  assert(!UniqueBaseOpcodeNames.empty() && "Canonical mapping not built");
+  auto It = std::find(UniqueBaseOpcodeNames.begin(),
+                      UniqueBaseOpcodeNames.end(), BaseName.str());
+  assert(It != UniqueBaseOpcodeNames.end() &&
+         "Base name not found in unique opcodes");
+  return std::distance(UniqueBaseOpcodeNames.begin(), It);
+}
+
+unsigned MIRVocabulary::getCanonicalOpcodeIndex(unsigned Opcode) const {
+  assert(isValid() && "MIR2Vec Vocabulary is invalid");
+  auto BaseOpcode = extractBaseOpcodeName(TII.getName(Opcode));
+  return getCanonicalIndexForBaseName(BaseOpcode);
+}
+
+std::string MIRVocabulary::getStringKey(unsigned Pos) const {
+  assert(isValid() && "MIR2Vec Vocabulary is invalid");
+  assert(Pos < Layout.TotalEntries && "Position out of bounds in vocabulary");
+
+  // For now, all entries are opcodes since we only have one section
+  if (Pos < Layout.OperandBase && Pos < UniqueBaseOpcodeNames.size()) {
+    // Convert canonical index back to base opcode name
+    auto It = UniqueBaseOpcodeNames.begin();
+    std::advance(It, Pos);
+    return *It;
+  }
+
+  llvm_unreachable("Invalid position in vocabulary");
+  return "";
+}
+
+void MIRVocabulary::generateStorage(const VocabMap &OpcodeMap) {
+
+  // Helper for handling missing entities in the vocabulary.
+  // Currently, we use a zero vector. In the future, we will throw an error to
+  // ensure that *all* known entities are present in the vocabulary.
+  auto handleMissingEntity = [](StringRef Key) {
+    LLVM_DEBUG(errs() << "MIR2Vec: Missing vocabulary entry for " << Key
+                      << "; using zero vector. This will result in an error "
+                         "in the future.\n");
+    ++MIRVocabMissCounter;
+  };
+
+  // Initialize opcode embeddings section
+  unsigned EmbeddingDim = OpcodeMap.begin()->second.size();
+  std::vector<Embedding> OpcodeEmbeddings(Layout.OperandBase,
+                                          Embedding(EmbeddingDim));
+
+  // Populate opcode embeddings using canonical mapping
+  for (auto COpcodeName : UniqueBaseOpcodeNames) {
+    if (auto It = OpcodeMap.find(COpcodeName); It != OpcodeMap.end()) {
+      auto COpcodeIndex = getCanonicalIndexForBaseName(COpcodeName);
+      assert(COpcodeIndex < Layout.OperandBase &&
+             "Canonical index out of bounds");
+      OpcodeEmbeddings[COpcodeIndex] = It->second;
+    } else {
+      handleMissingEntity(COpcodeName);
+    }
+  }
+
+  // TODO: Add operand/argument embeddings as additional sections
+  // This will require extending the vocabulary format and layout
+
+  // Scale the vocabulary sections based on the provided weights
+  auto scaleVocabSection = [](std::vector<Embedding> &Embeddings,
+                              double Weight) {
+    for (auto &Embedding : Embeddings)
+      Embedding *= Weight;
+  };
+  scaleVocabSection(OpcodeEmbeddings, OpcWeight);
+
+  std::vector<std::vector<Embedding>> Sections(1);
+  Sections[0] = std::move(OpcodeEmbeddings);
+
+  Storage = ir2vec::VocabStorage(std::move(Sections));
+}
+
+void MIRVocabulary::buildCanonicalOpcodeMapping() {
+  // Check if already built
+  if (!UniqueBaseOpcodeNames.empty())
+    return;
+
+  // Build mapping from opcodes to canonical base opcode indices
+  for (unsigned Opcode = 0; Opcode < TII.getNumOpcodes(); ++Opcode) {
+    std::string BaseOpcode = extractBaseOpcodeName(TII.getName(Opcode));
+    UniqueBaseOpcodeNames.insert(BaseOpcode);
+  }
+
+  LLVM_DEBUG(dbgs() << "MIR2Vec: Built canonical mapping for target with "
+                    << UniqueBaseOpcodeNames.size()
+                    << " unique base opcodes\n");
+}
+
+//===----------------------------------------------------------------------===//
+// MIR2VecVocabLegacyAnalysis Implementation
+//===----------------------------------------------------------------------===//
+
+char MIR2VecVocabLegacyAnalysis::ID = 0;
+INITIALIZE_PASS_BEGIN(MIR2VecVocabLegacyAnalysis, "mir2vec-vocab-analysis",
+                      "MIR2Vec Vocabulary Analysis", false, true)
+INITIALIZE_PASS_DEPENDENCY(MachineModuleInfoWrapperPass)
+INITIALIZE_PASS_END(MIR2VecVocabLegacyAnalysis, "mir2vec-vocab-analysis",
+                    "MIR2Vec Vocabulary Analysis", false, true)
+
+StringRef MIR2VecVocabLegacyAnalysis::getPassName() const {
+  return "MIR2Vec Vocabulary Analysis";
+}
+
+Error MIR2VecVocabLegacyAnalysis::readVocabulary() {
+  // TODO: Extend vocabulary format to support multiple sections
+  // (opcodes, operands, etc.) similar to IR2Vec structure
+  if (VocabFile.empty())
+    return createStringError(
+        errc::invalid_argument,
+        "MIR2Vec vocabulary file path not specified; set it "
+        "using --mir2vec-vocab-path");
+
+  auto BufOrError = MemoryBuffer::getFileOrSTDIN(VocabFile, /*IsText=*/true);
+  if (!BufOrError)
+    return createFileError(VocabFile, BufOrError.getError());
+
+  auto Content = BufOrError.get()->getBuffer();
+
+  Expected<json::Value> ParsedVocabValue = json::parse(Content);
+  if (!ParsedVocabValue)
+    return ParsedVocabValue.takeError();
+
+  unsigned Dim = 0;
+  if (auto Err = ir2vec::VocabStorage::parseVocabSection(
+          "entities", *ParsedVocabValue, StrVocabMap, Dim))
+    return Err;
+
+  return Error::success();
+}
+
+void MIR2VecVocabLegacyAnalysis::emitError(Error Err, LLVMContext &Ctx) {
+  Ctx.emitError(toString(std::move(Err)));
+}
+
+mir2vec::MIRVocabulary
+MIR2VecVocabLegacyAnalysis::getMIR2VecVocabulary(const Module &M) {
+  if (StrVocabMap.empty()) {
+    if (Error Err = readVocabulary()) {
+      emitError(std::move(Err), M.getContext());
+      return mir2vec::MIRVocabulary(std::move(StrVocabMap), nullptr);
+    }
+  }
+
+  // Get machine module info to access machine functions and target info
+  MachineModuleInfo &MMI = getAnalysis<MachineModuleInfoWrapperPass>().getMMI();
+
+  // Find first available machine function to get target instruction info
+  for (const auto &F : M) {
+    if (F.isDeclaration())
+      continue;
+
+    if (auto *MF = MMI.getMachineFunction(F)) {
+      const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
+      return mir2vec::MIRVocabulary(std::move(StrVocabMap), TII);
+    }
+  }
+
+  // No machine functions available - return invalid vocabulary
+  emitError(make_error<StringError>("No machine functions found in module",
+                                    inconvertibleErrorCode()),
+            M.getContext());
+  return mir2vec::MIRVocabulary(std::move(StrVocabMap), nullptr);
+}
+
+//===----------------------------------------------------------------------===//
+// Printer Passes Implementation
+//===----------------------------------------------------------------------===//
+
+char MIR2VecVocabPrinterLegacyPass::ID = 0;
+INITIALIZE_PASS_BEGIN(MIR2VecVocabPrinterLegacyPass, "print-mir2vec-vocab",
+                      "MIR2Vec Vocabulary Printer Pass", false, true)
+INITIALIZE_PASS_DEPENDENCY(MIR2VecVocabLegacyAnalysis)
+INITIALIZE_PASS_DEPENDENCY(MachineModuleInfoWrapperPass)
+INITIALIZE_PASS_END(MIR2VecVocabPrinterLegacyPass, "print-mir2vec-vocab",
+                    "MIR2Vec Vocabulary Printer Pass", false, true)
+
+bool MIR2VecVocabPrinterLegacyPass::runOnMachineFunction(MachineFunction &MF) {
+  return false;
+}
+
+bool MIR2VecVocabPrinterLegacyPass::doFinalization(Module &M) {
+  auto &Analysis = getAnalysis<MIR2VecVocabLegacyAnalysis>();
+  auto MIR2VecVocab = Analysis.getMIR2VecVocabulary(M);
+
+  if (!MIR2VecVocab.isValid()) {
+    OS << "MIR2Vec Vocabulary Printer: Invalid vocabulary\n";
+    return false;
+  }
+
+  unsigned Pos = 0;
+  for (const auto &Entry : MIR2VecVocab) {
+    OS << "Key: " << MIR2VecVocab.getStringKey(Pos++) << ": ";
+    Entry.print(OS);
+  }
+
+  return false;
+}
+
+MachineFunctionPass *
+llvm::createMIR2VecVocabPrinterLegacyPass(raw_ostream &OS) {
+  return new MIR2VecVocabPrinterLegacyPass(OS);
+}