[clang] [llvm] [clang][ssaf] Add CallGraph summary and extractor (PR #188753)

[Balázs Benics via llvm-commits]

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@@ -0,0 +1,110 @@
+//===- CallGraphExtractor.cpp - Call Graph Summary Extractor --------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/DeclObjC.h"
+#include "clang/Analysis/AnalysisDeclContext.h"
+#include "clang/Analysis/CallGraph.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/ScalableStaticAnalysisFramework/Analyses/CallGraph/CallGraphSummary.h"
+#include "clang/ScalableStaticAnalysisFramework/Core/ASTEntityMapping.h"
+#include "clang/ScalableStaticAnalysisFramework/Core/TUSummary/ExtractorRegistry.h"
+#include "clang/ScalableStaticAnalysisFramework/Core/TUSummary/TUSummaryBuilder.h"
+#include "llvm/ADT/STLExtras.h"
+#include <memory>
+
+using namespace clang;
+using namespace ssaf;
+
+namespace {
+class CallGraphExtractor final : public TUSummaryExtractor {
+public:
+  using TUSummaryExtractor::TUSummaryExtractor;
+
+private:
+  void HandleTranslationUnit(ASTContext &Ctx) override;
+
+  void handleCallGraphNode(const ASTContext &Ctx, const CallGraphNode *N);
+};
+} // namespace
+
+void CallGraphExtractor::HandleTranslationUnit(ASTContext &Ctx) {
+  CallGraph CG;
+  CG.addToCallGraph(
+      const_cast<TranslationUnitDecl *>(Ctx.getTranslationUnitDecl()));
+
+  for (const auto &N : llvm::make_second_range(CG)) {
+    if (N && N->getDecl() && N->getDefinition())
+      handleCallGraphNode(Ctx, N.get());
+  }
+}
+
+void CallGraphExtractor::handleCallGraphNode(const ASTContext &Ctx,
+                                             const CallGraphNode *N) {
+  const FunctionDecl *Definition = N->getDefinition();
+
+  // Ignore templates for now.
+  if (Definition->isTemplated())
+    return;
+
+  auto CallerName = getEntityName(Definition);
+  if (!CallerName)
+    return;
+
+  auto FnSummary = std::make_unique<CallGraphSummary>();
+
+  PresumedLoc Loc =
+      Ctx.getSourceManager().getPresumedLoc(Definition->getLocation());
+  FnSummary->Definition.File = Loc.getFilename();
+  FnSummary->Definition.Line = Loc.getLine();
+  FnSummary->Definition.Column = Loc.getColumn();
+  FnSummary->PrettyName = AnalysisDeclContext::getFunctionName(Definition);
+
+  for (const auto &Record : N->callees()) {
+    const Decl *CalleeDecl = Record.Callee->getDecl();
+    if (!CalleeDecl) {
+      FnSummary->HasIndirectCalls = true;
+      continue;
+    }
+    assert(!CalleeDecl->isTemplated());
+
+    // Objective-C methods might be replaced at runtime, so they are effectively
+    // indirect calls.
+    if (isa<ObjCMethodDecl>(CalleeDecl)) {
+      FnSummary->HasIndirectCalls = true;
+      continue;
+    }
+
+    // Treat virtual functions as indirect calls for now.
+    if (const auto *MD = dyn_cast_or_null<CXXMethodDecl>(CalleeDecl);
----------------
steakhal wrote:

Reworked in 02be6403cc44c2b3658078b4fd6b985b7fe0b07b

https://github.com/llvm/llvm-project/pull/188753