[IR2Vec] Add llvm-ir2vec tool for generating triplet embeddings (#147842)

Add a new LLVM tool `llvm-ir2vec`. This tool is primarily intended to generate triplets for training the vocabulary (#141834) and to potentially generate the embeddings in a stand alone manner.

This PR introduces the tool with triplet generation functionality. In the upcoming PRs I'll add scripts under `utils/mlgo` to complete the vocabulary tooling. #147844 adds embedding generation logic to the tool.

(Tracking issue - #141817)

Author: svkeerthy

llvm/test/CMakeLists.txt

@@ -97,6 +97,7 @@ set(LLVM_TEST_DEPENDS
           llvm-exegesis
           llvm-extract
           llvm-gsymutil
+          llvm-ir2vec
           llvm-isel-fuzzer
           llvm-ifs
           llvm-install-name-tool

llvm/test/lit.cfg.py

@@ -197,6 +197,7 @@ def get_asan_rtlib():
         "llvm-dlltool",
         "llvm-exegesis",
         "llvm-extract",
+        "llvm-ir2vec",
         "llvm-isel-fuzzer",
         "llvm-ifs",
         "llvm-install-name-tool",

llvm/test/tools/llvm-ir2vec/triplets.ll

@@ -0,0 +1,38 @@
+; RUN: llvm-ir2vec %s | FileCheck %s -check-prefix=TRIPLETS
+
+define i32 @simple_add(i32 %a, i32 %b) {
+entry:
+  %add = add i32 %a, %b
+  ret i32 %add
+}
+
+define i32 @simple_mul(i32 %x, i32 %y) {
+entry:
+  %mul = mul i32 %x, %y
+  ret i32 %mul
+}
+
+define i32 @test_function(i32 %arg1, i32 %arg2) {
+entry:
+  %local1 = alloca i32, align 4
+  %local2 = alloca i32, align 4
+  store i32 %arg1, ptr %local1, align 4
+  store i32 %arg2, ptr %local2, align 4
+  %load1 = load i32, ptr %local1, align 4
+  %load2 = load i32, ptr %local2, align 4
+  %result = add i32 %load1, %load2
+  ret i32 %result
+}
+
+; TRIPLETS: Add IntegerTy Variable Variable
+; TRIPLETS-NEXT: Ret VoidTy Variable
+; TRIPLETS-NEXT: Mul IntegerTy Variable Variable
+; TRIPLETS-NEXT: Ret VoidTy Variable
+; TRIPLETS-NEXT: Alloca PointerTy Constant
+; TRIPLETS-NEXT: Alloca PointerTy Constant
+; TRIPLETS-NEXT: Store VoidTy Variable Pointer
+; TRIPLETS-NEXT: Store VoidTy Variable Pointer
+; TRIPLETS-NEXT: Load IntegerTy Pointer
+; TRIPLETS-NEXT: Load IntegerTy Pointer
+; TRIPLETS-NEXT: Add IntegerTy Variable Variable
+; TRIPLETS-NEXT: Ret VoidTy Variable

llvm/tools/llvm-ir2vec/CMakeLists.txt

@@ -0,0 +1,10 @@
+set(LLVM_LINK_COMPONENTS
+  Analysis
+  Core
+  IRReader
+  Support
+  )
+
+add_llvm_tool(llvm-ir2vec
+  llvm-ir2vec.cpp
+  )

llvm/tools/llvm-ir2vec/llvm-ir2vec.cpp

@@ -0,0 +1,154 @@
+//===- llvm-ir2vec.cpp - IR2Vec Embedding Generation Tool -----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file implements the IR2Vec embedding generation tool.
+///
+/// Currently supports triplet generation for vocabulary training.
+/// Future updates will support embedding generation using trained vocabulary.
+///
+/// Usage: llvm-ir2vec input.bc -o triplets.txt
+///
+/// TODO: Add embedding generation mode with vocabulary support
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/IR2Vec.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Type.h"
+#include "llvm/IRReader/IRReader.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/Errc.h"
+#include "llvm/Support/InitLLVM.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+using namespace ir2vec;
+
+#define DEBUG_TYPE "ir2vec"
+
+static cl::OptionCategory IR2VecToolCategory("IR2Vec Tool Options");
+
+static cl::opt<std::string> InputFilename(cl::Positional,
+                                          cl::desc("<input bitcode file>"),
+                                          cl::Required,
+                                          cl::cat(IR2VecToolCategory));
+
+static cl::opt<std::string> OutputFilename("o", cl::desc("Output filename"),
+                                           cl::value_desc("filename"),
+                                           cl::init("-"),
+                                           cl::cat(IR2VecToolCategory));
+
+namespace {
+
+/// Helper class for collecting IR information and generating triplets
+class IR2VecTool {
+private:
+  Module &M;
+
+public:
+  explicit IR2VecTool(Module &M) : M(M) {}
+
+  /// Generate triplets for the entire module
+  void generateTriplets(raw_ostream &OS) const {
+    for (const Function &F : M)
+      generateTriplets(F, OS);
+  }
+
+  /// Generate triplets for a single function
+  void generateTriplets(const Function &F, raw_ostream &OS) const {
+    if (F.isDeclaration())
+      return;
+
+    std::string LocalOutput;
+    raw_string_ostream LocalOS(LocalOutput);
+
+    for (const BasicBlock &BB : F)
+      traverseBasicBlock(BB, LocalOS);
+
+    LocalOS.flush();
+    OS << LocalOutput;
+  }
+
+private:
+  /// Process a single basic block for triplet generation
+  void traverseBasicBlock(const BasicBlock &BB, raw_string_ostream &OS) const {
+    // Consider only non-debug and non-pseudo instructions
+    for (const auto &I : BB.instructionsWithoutDebug()) {
+      StringRef OpcStr = Vocabulary::getVocabKeyForOpcode(I.getOpcode());
+      StringRef TypeStr =
+          Vocabulary::getVocabKeyForTypeID(I.getType()->getTypeID());
+
+      OS << '\n' << OpcStr << ' ' << TypeStr << ' ';
+
+      LLVM_DEBUG({
+        I.print(dbgs());
+        dbgs() << "\n";
+        I.getType()->print(dbgs());
+        dbgs() << " Type\n";
+      });
+
+      for (const Use &U : I.operands())
+        OS << Vocabulary::getVocabKeyForOperandKind(
+                  Vocabulary::getOperandKind(U.get()))
+           << ' ';
+    }
+  }
+};
+
+Error processModule(Module &M, raw_ostream &OS) {
+  IR2VecTool Tool(M);
+  Tool.generateTriplets(OS);
+
+  return Error::success();
+}
+
+} // anonymous namespace
+
+int main(int argc, char **argv) {
+  InitLLVM X(argc, argv);
+  cl::HideUnrelatedOptions(IR2VecToolCategory);
+  cl::ParseCommandLineOptions(
+      argc, argv,
+      "IR2Vec - Triplet Generation Tool\n"
+      "Generates triplets for vocabulary training from LLVM IR.\n"
+      "Future updates will support embedding generation.\n\n"
+      "Usage:\n"
+      "  llvm-ir2vec input.bc -o triplets.txt\n");
+
+  // Parse the input LLVM IR file
+  SMDiagnostic Err;
+  LLVMContext Context;
+  std::unique_ptr<Module> M = parseIRFile(InputFilename, Err, Context);
+  if (!M) {
+    Err.print(argv[0], errs());
+    return 1;
+  }
+
+  std::error_code EC;
+  raw_fd_ostream OS(OutputFilename, EC);
+  if (EC) {
+    errs() << "Error opening output file: " << EC.message() << "\n";
+    return 1;
+  }
+
+  if (Error Err = processModule(*M, OS)) {
+    handleAllErrors(std::move(Err), [&](const ErrorInfoBase &EIB) {
+      errs() << "Error: " << EIB.message() << "\n";
+    });
+    return 1;
+  }
+
+  return 0;
+}