[llvm] Call instr execution in ir2vec (PR #167233)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-llvm-analysis

@llvm/pr-subscribers-mlgo

Author: Naga Rohith Kumar Jakkala (NagaRohithKumarJakkala)

<details>
<summary>Changes</summary>

- This pull request is for llvm-ir2vec which implements the call instruction. 
- which gets the call graph information
- and implements call instruction in flowaware instruction without using the funcVectorMap cache.
- and i want to know how to start with cyclic dependency

---
Full diff: https://github.com/llvm/llvm-project/pull/167233.diff


2 Files Affected:

- (modified) llvm/include/llvm/Analysis/IR2Vec.h (+4) 
- (modified) llvm/lib/Analysis/IR2Vec.cpp (+40-1) 


``````````diff
diff --git a/llvm/include/llvm/Analysis/IR2Vec.h b/llvm/include/llvm/Analysis/IR2Vec.h
index 7a68773a2643a..09a1b00e0391e 100644
--- a/llvm/include/llvm/Analysis/IR2Vec.h
+++ b/llvm/include/llvm/Analysis/IR2Vec.h
@@ -598,12 +598,16 @@ class LLVM_ABI FlowAwareEmbedder : public Embedder {
   // FlowAware embeddings would benefit from caching instruction embeddings as
   // they are reused while computing the embeddings of other instructions.
   mutable InstEmbeddingsMap InstVecMap;
+  static SmallVector<Function *, 15> FuncStack;
   Embedding computeEmbeddings(const Instruction &I) const override;
+  static SmallMapVector<const Function *, SmallVector<const Function *, 10>, 16>
+      FuncCallMap;
 
 public:
   FlowAwareEmbedder(const Function &F, const Vocabulary &Vocab)
       : Embedder(F, Vocab) {}
   void invalidateEmbeddings() override { InstVecMap.clear(); }
+  static void computeFuncCallMap(Module &M);
 };
 
 } // namespace ir2vec
diff --git a/llvm/lib/Analysis/IR2Vec.cpp b/llvm/lib/Analysis/IR2Vec.cpp
index 85b5372c961c1..2493cb4f75993 100644
--- a/llvm/lib/Analysis/IR2Vec.cpp
+++ b/llvm/lib/Analysis/IR2Vec.cpp
@@ -17,6 +17,7 @@
 #include "llvm/ADT/Sequence.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/CallGraph.h"
 #include "llvm/IR/CFG.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/PassManager.h"
@@ -61,7 +62,10 @@ cl::opt<IR2VecKind> IR2VecEmbeddingKind(
                           "Generate flow-aware embeddings")),
     cl::init(IR2VecKind::Symbolic), cl::desc("IR2Vec embedding kind"),
     cl::cat(IR2VecCategory));
-
+// static members of Flowaware Embeddings
+SmallVector<Function *, 15> FlowAwareEmbedder::FuncStack;
+SmallMapVector<const Function *, SmallVector<const Function *, 10>, 16>
+      FlowAwareEmbedder::FuncCallMap;
 } // namespace ir2vec
 } // namespace llvm
 
@@ -207,6 +211,23 @@ Embedding FlowAwareEmbedder::computeEmbeddings(const Instruction &I) const {
   // TODO: Handle call instructions differently.
   // For now, we treat them like other instructions
   Embedding ArgEmb(Dimension, 0);
+
+  if (isa<CallInst>(I)) {
+    const auto *Ci = dyn_cast<CallInst>(&I);
+    Function *Func = Ci->getCalledFunction();
+    if (Func) {
+      if (!Func->isDeclaration() &&
+          std::find(FuncStack.begin(), FuncStack.end(), Func) ==
+              FuncStack.end()) {
+        FuncStack.push_back(Func);
+        auto Emb = Embedder::create(IR2VecEmbeddingKind, *Func, Vocab);
+        auto FuncVec = Emb->getFunctionVector();
+        std::transform(ArgEmb.begin(), ArgEmb.end(), FuncVec.begin(),
+                       FuncVec.end(), std::plus<double>());
+        FuncStack.pop_back();
+      }
+    }
+  }
   for (const auto &Op : I.operands()) {
     // If the operand is defined elsewhere, we use its embedding
     if (const auto *DefInst = dyn_cast<Instruction>(Op)) {
@@ -245,6 +266,24 @@ Embedding FlowAwareEmbedder::computeEmbeddings(const Instruction &I) const {
   return InstVector;
 }
 
+void FlowAwareEmbedder::computeFuncCallMap(Module &M) {
+  CallGraph Cg = CallGraph(M);
+  for (auto CallItr = Cg.begin(); CallItr != Cg.end(); CallItr++) {
+    if (CallItr->first && !CallItr->first->isDeclaration()) {
+      const auto *ParentFunc = CallItr->first;
+      CallGraphNode *Cgn = CallItr->second.get();
+      if (Cgn) {
+        for (auto It = Cgn->begin(); It != Cgn->end(); It++) {
+          const auto *Func = It->second->getFunction();
+          if (Func && !Func->isDeclaration()) {
+            FuncCallMap[ParentFunc].push_back(Func);
+          }
+        }
+      }
+    }
+  }
+}
+
 // ==----------------------------------------------------------------------===//
 // VocabStorage
 //===----------------------------------------------------------------------===//

``````````

</details>


https://github.com/llvm/llvm-project/pull/167233