Better branch detection model

For loops are now broken up into 2 branches: 1 (init) and 2 (cond + inc).

op-finder/CMakeLists.txt

@@ -25,7 +25,7 @@ add_executable(op-finder
     OperationFinderAstVisitor.cpp
     OperationFinderAstConsumer.cpp
     OperationFinderAstAction.cpp
-)
+    OperationLog.cpp)
 
 target_include_directories(op-finder
     PRIVATE

op-finder/OperationFinder.cpp

@@ -11,6 +11,35 @@
 using namespace clang;
 using namespace clang::ast_matchers;
 
+namespace
+{
+
+std::string ResolveTypeName(const QualType& t)
+{
+  if (t->isTypedefNameType())
+  {
+    const TypedefType* tdt = cast<TypedefType>(t);
+    assert(tdt);
+    llvm::outs() << "Typedef type: " << t.getAsString()
+                 << ", underlying: " << tdt->desugar().getAsString()
+                 << ".";
+
+    return tdt->desugar().getAsString();
+  }
+  else if (t->isBuiltinType())
+  {
+    llvm::outs() << "Builtin type: " << t.getAsString() << ".";
+    return t.getAsString();
+  }
+  else
+  {
+    llvm::outs() << "Other type: " << t.getAsString() << ".";
+    return t.getAsString();
+  }
+};
+
+}
+
 OperationFinder::OperationFinder(IOperationOutput* storage)
   : _storage(storage)
 {
@@ -19,113 +48,123 @@ OperationFinder::OperationFinder(IOperationOutput* storage)
 
 void OperationFinder::processArithmetic(const clang::BinaryOperator* op, const clang::SourceManager& source_manager)
 {
-  const auto [file_name, line_number, column_number] = resolveLocations(op, source_manager);
+  auto [file_name, log] = _createBaseOperationLog(op, source_manager);
+  const std::string op_code = getOpcode(op).str();
 
-  llvm::outs()  << file_name << ":"
+  llvm::outs() << "\n\tBinary arithmetic: Type: " << op_code;
-                << line_number << ":"
-                << column_number << ":"
-                << "Binary arithmetic: Type: " << getOpcode(op) << " LHS: ";
 
-  OperationLog log;
+  log.entry_type = OperationLog::BasicOperation::TYPE_NAME;
-  log.line = line_number;
+  log.entry = _createBasicOperationLogEntry(op_code, op, op->getLHS(), op->getRHS());
-  log.operation = getOpcode(op).str();
-  log.current_for_loops = _for_loop_stack;
-  log.is_fallthrough = _in_fallthrough;
 
-  _processExpressionTypes(log, op, op->getLHS(), op->getRHS());
+  _storage->pushOperation(file_name, std::move(log));
-
-  _storage->pushOperation(file_name, log);
 
   llvm::outs() << "\n";
 }
 
 void OperationFinder::processUnaryArithmetic(const clang::UnaryOperator* op, const clang::SourceManager& source_manager)
 {
-  const Expr* lhs = op->getExprStmt();
+  auto [file_name, log] = _createBaseOperationLog(op, source_manager);
+  const std::string op_code = getOpcode(op).str();
 
-  assert(op);
+  llvm::outs() << "\n\tUnary arithmetic: Type: " << op_code;
-  assert(lhs);
 
-  const auto [file_name, line_number, column_number] = resolveLocations(op, source_manager);
+  log.entry_type = OperationLog::BasicOperation::TYPE_NAME;
+  log.entry = _createBasicOperationLogEntry(op_code, op, op->getExprStmt(), nullptr);
 
-  llvm::outs()  << file_name << ":"
+  _storage->pushOperation(file_name, std::move(log));
-                << line_number << ":"
-                << column_number << ":"
-                << "Unary arithmetic: Type: " << getOpcode(op) << " LHS: ";
-
-  OperationLog log;
-  log.line = line_number;
-  log.operation = getOpcode(op).str();
-  log.current_for_loops = _for_loop_stack;
-  log.is_fallthrough = _in_fallthrough;
-
-  _processExpressionTypes(log, op, lhs, nullptr);
-
-  _storage->pushOperation(file_name, log);
 
   llvm::outs() << "\n";
 }
 
-void OperationFinder::fallthroughBranchEntered()
+void OperationFinder::processFunctionCall(const clang::CallExpr* call, const SourceManager& source_manager)
 {
-  _in_fallthrough = true;
+  const FunctionDecl* func = call->getDirectCallee();
+
+  assert(func);
+
+  auto [file_name, log] = _createBaseOperationLog(call, source_manager);
+  const std::string func_name = func->getNameAsString();
+
+  llvm::outs() << "\n\tFunction call: func name: " << func_name << "\n\tResult eval type: ";
+
+  const std::string res_type = ResolveTypeName(func->getType());
+
+  auto func_call = std::make_unique<OperationLog::FunctionCall>();
+  func_call->function_name = func_name;
+  func_call->call_result_type = res_type;
+
+  log.entry_type = OperationLog::FunctionCall::TYPE_NAME;
+  log.entry = std::move(func_call);
+
+  _storage->pushOperation(file_name, std::move(log));
+
+  llvm::outs() << "\n";
 }
 
-void OperationFinder::fallthroughBranchExited()
+void OperationFinder::processArraySubscript(const clang::ArraySubscriptExpr* subscript, const clang::SourceManager& source_manager)
 {
-  _in_fallthrough = false;
+  auto [file_name, log] = _createBaseOperationLog(subscript, source_manager);
+
+  llvm::outs() << "\n\tSubscript:";
+
+  log.entry_type = OperationLog::BasicOperation::TYPE_NAME;
+  log.entry = _createBasicOperationLogEntry("subscript", subscript, subscript->getBase(), subscript->getIdx());
+
+  _storage->pushOperation(file_name, std::move(log));
+
+  llvm::outs() << "\n";
 }
 
-void OperationFinder::forLoopEntered()
+void OperationFinder::branchEntered()
 {
-  _for_loop_stack.push_back(_next_for_loop_id);
+  _current_branch++;
-
+  llvm::outs() << "Branch entered: " << _current_branch << "\n";
-  _next_for_loop_id++;
 }
 
-void OperationFinder::forLoopExited()
+void OperationFinder::branchExited()
 {
-  _for_loop_stack.pop_back();
+  llvm::outs() << "Branch exited: " << _current_branch << "\n";
+
+  _current_branch--;
+
+  assert(_current_branch > -1);
 }
 
-void OperationFinder::_processExpressionTypes(OperationLog& log, const Expr* source, const Expr* op1, const Expr* op2)
+std::unique_ptr<OperationLog::BasicOperation>
+        OperationFinder::_createBasicOperationLogEntry(const std::string& opcode, const Expr* source, const Expr* op1, const Expr* op2)
 {
+  auto log = std::make_unique<OperationLog::BasicOperation>();
 
-  auto printTypeName = [](const QualType& t) -> std::string
+  log->operation_name = opcode;
-  {
-    if (t->isTypedefNameType())
-    {
-      const TypedefType* tdt = cast<TypedefType>(t);
-      assert(tdt);
-      llvm::outs() << "Typedef type: " << t.getAsString()
-                   << ", underlying: " << tdt->desugar().getAsString()
-                   << ".";
 
-      return tdt->desugar().getAsString();
+  llvm::outs() << "\n\tExpression eval type: ";
-    }
+  log->type_result = ResolveTypeName(source->getType());
-    else if (t->isBuiltinType())
-    {
-      llvm::outs() << "Builtin type: " << t.getAsString() << ".";
-      return t.getAsString();
-    }
-    else
-    {
-      llvm::outs() << "Other type: " << t.getAsString() << ".";
-      return t.getAsString();
-    }
-  };
-
-  llvm::outs() << "Expression types:\n\tExpression eval type: ";
-  log.operand_result = printTypeName(source->getType());
 
   if (op1)
   {
     llvm::outs() << "\n\tLHS eval type: ";
-    log.operand_lhs = printTypeName(op1->getType());
+    log->type_lhs = ResolveTypeName(op1->getType());
   }
   if (op2)
   {
     llvm::outs() << "\n\tRHS eval type: ";
-    log.operand_rhs = printTypeName(op2->getType());
+    log->type_rhs = ResolveTypeName(op2->getType());
   }
+
+  return log;
+}
+
+std::pair<std::string, OperationLog> OperationFinder::_createBaseOperationLog(const clang::Stmt* stmt, const clang::SourceManager& source_manager)
+{
+  const auto [file_name, line_number, column_number] = resolveLocations(stmt, source_manager);
+
+  OperationLog log;
+  log.line = line_number;
+  log.branch_number = _current_branch;
+
+  llvm::outs()  << file_name << ":"
+                << line_number << ":"
+                << column_number << ":";
+
+  return { file_name, std::move(log) };
 }

op-finder/OperationFinder.hpp

@@ -16,19 +16,19 @@ public:
 
   void processArithmetic(const clang::BinaryOperator* op, const clang::SourceManager& source_manager);
   void processUnaryArithmetic(const clang::UnaryOperator* op, const clang::SourceManager& source_manager);
+  void processFunctionCall(const clang::CallExpr* call, const clang::SourceManager& source_manager);
+  void processArraySubscript(const clang::ArraySubscriptExpr* subscript, const clang::SourceManager& source_manager);
 
-  void fallthroughBranchEntered();
+  void branchEntered();
-  void fallthroughBranchExited();
+  void branchExited();
-
-  void forLoopEntered();
-  void forLoopExited();
 
 private:
-  void _processExpressionTypes(OperationLog& log, const clang::Expr* source, const clang::Expr* op1, const clang::Expr* op2);
+  std::unique_ptr<OperationLog::BasicOperation>
+          _createBasicOperationLogEntry(const std::string& opcode, const clang::Expr* source, const clang::Expr* op1, const clang::Expr* op2);
 
-  int _next_for_loop_id = 0;
+  std::pair<std::string, OperationLog> _createBaseOperationLog(const clang::Stmt* stmt, const clang::SourceManager& source_manager);
-  bool _in_fallthrough = false;
+
-  std::vector<int> _for_loop_stack;
+  int _current_branch = 0;
   IOperationOutput* _storage;
 };
 

op-finder/OperationFinderAstVisitor.cpp

@@ -43,21 +43,32 @@ bool OperationFinderAstVisitor::VisitUnaryOperator(clang::UnaryOperator* op)
   return true;
 }
 
+bool OperationFinderAstVisitor::VisitCallExpr(clang::CallExpr* call)
+{
+  assert(_context);
+
+  _op_finder->processFunctionCall(call, _context->getSourceManager());
+
+  return true;
+}
+
+bool OperationFinderAstVisitor::VisitArraySubscriptExpr(clang::ArraySubscriptExpr* subscript)
+{
+  assert(_context);
+
+  _op_finder->processArraySubscript(subscript, _context->getSourceManager());
+
+  return true;
+}
+
 bool OperationFinderAstVisitor::dataTraverseStmtPre(clang::Stmt* stmt)
 {
   assert(_context);
 
-  if (auto* loop = clang::dyn_cast<clang::ForStmt>(stmt))
+  if (clang::Stmt* branch_entry = _isBranchEntry(stmt))
   {
-    if (loop->getInit())
+    _branch_stack.push_back(branch_entry);
-    {
+    _op_finder->branchEntered();
-      _loop_init = loop->getInit();
-      _op_finder->fallthroughBranchEntered();
-    }
-    else
-    {
-      _op_finder->forLoopEntered();
-    }
   }
 
   return true;
@@ -67,16 +78,77 @@ bool OperationFinderAstVisitor::dataTraverseStmtPost(clang::Stmt* stmt)
 {
   assert(_context);
 
-  if (_loop_init && _loop_init == stmt)
+  if (_loop_header.in_loop_header && (_loop_header.init == stmt || _loop_header.header_end == stmt))
   {
-    _op_finder->forLoopEntered();
+    if (_loop_header.header_end == stmt)
-    _op_finder->fallthroughBranchExited();
+    {
-    _loop_init = nullptr;
+      assert(_branch_stack.back() == stmt);
+      _branch_stack.pop_back();
+      _op_finder->branchExited();
+
+      if (_loop_header.init)
+      {
+        assert(_branch_stack.back() == _loop_header.init);
+        _branch_stack.pop_back();
+        _op_finder->branchExited();
+      }
+
+      _loop_header = {};
+    }
+    else if (_loop_header.init == stmt && !_loop_header.header_end)
+    {
+      assert(_branch_stack.back() == stmt);
+      _branch_stack.pop_back();
+      _op_finder->branchExited();
+
+      _loop_header = {};
+    }
   }
-  else if (clang::dyn_cast<clang::ForStmt>(stmt))
+  else if (!_branch_stack.empty() && _branch_stack.back() == stmt)
   {
-    _op_finder->forLoopExited();
+    _branch_stack.pop_back();
+    _op_finder->branchExited();
+  }
+  else
+  {
+    assert(std::find(_branch_stack.cbegin(), _branch_stack.cend(), stmt)
+           == _branch_stack.cend());
   }
 
   return true;
 }
+
+clang::Stmt* OperationFinderAstVisitor::_isBranchEntry(clang::Stmt* stmt)
+{
+  if (auto* loop = clang::dyn_cast<clang::ForStmt>(stmt))
+  {
+    _loop_header.init = loop->getInit();
+
+    if (loop->getCond())
+    {
+      _loop_header.header_start = loop->getCond();
+      _loop_header.header_end = loop->getCond();
+    }
+
+    if (loop->getInc())
+    {
+      if (!_loop_header.header_start)
+        _loop_header.header_start = loop->getInc();
+
+      _loop_header.header_end = loop->getInc();
+    }
+
+    _loop_header.in_loop_header = _loop_header.init || _loop_header.header_end;
+
+    if (_loop_header.init)
+      return _loop_header.init;
+    else if (_loop_header.header_start)
+      return _loop_header.header_end;
+  }
+  else if (_loop_header.in_loop_header && _loop_header.header_start == stmt)
+  {
+    return _loop_header.header_end;
+  }
+
+  return nullptr;
+}

op-finder/OperationFinderAstVisitor.hpp

@@ -20,6 +20,8 @@ public:
   bool VisitForStmt(clang::ForStmt* stmt);
   bool VisitBinaryOperator(clang::BinaryOperator* op);
   bool VisitUnaryOperator(clang::UnaryOperator* op);
+  bool VisitCallExpr(clang::CallExpr* call);
+  bool VisitArraySubscriptExpr(clang::ArraySubscriptExpr* subscript);
 
   bool dataTraverseStmtPre(clang::Stmt* stmt);
   bool dataTraverseStmtPost(clang::Stmt* stmt);
@@ -28,7 +30,19 @@ private:
   clang::ASTContext* _context;
   OperationFinder* _op_finder;
 
-  clang::Stmt* _loop_init = nullptr;
+  struct _LoopHeaderStateMachine
+  {
+    bool in_loop_header = false;
+    clang::Stmt* init = nullptr;
+    clang::Stmt* header_start = nullptr;
+    clang::Stmt* header_end = nullptr;
+  };
+
+  _LoopHeaderStateMachine _loop_header;
+
+  std::vector<clang::Stmt*> _branch_stack;
+
+  clang::Stmt* _isBranchEntry(clang::Stmt* stmt);
 };
 
 #endif //C_ANALYZER_OPERATIONFINDERASTVISITOR_HPP

op-finder/OperationLog.cpp

@@ -0,0 +1,44 @@
+//
+// Created by erki on 06.03.21.
+//
+
+#include "OperationLog.hpp"
+
+namespace
+{
+
+template<typename T>
+std::unique_ptr<T> DecodeType(const nlohmann::json& j, const std::string& entry_type)
+{
+  if (entry_type == T::TYPE_NAME)
+  {
+    auto t = std::make_unique<T>();
+    j.get_to(*t);
+
+    return t;
+  }
+  else
+  {
+    return nullptr;
+  }
+}
+
+}
+
+nlohmann::json OperationLog::FunctionCall::toJson() const
+{
+  return *this;
+}
+
+nlohmann::json OperationLog::BasicOperation::toJson() const
+{
+  return *this;
+}
+
+void OperationLog::DecodeEntry(const nlohmann::json& j)
+{
+  if ((entry = DecodeType<BasicOperation>(j, entry_type)))
+    return;
+  else if ((entry = DecodeType<FunctionCall>(j, entry_type)))
+    return;
+}

op-finder/OperationLog.hpp

@@ -6,16 +6,50 @@
 #define C_ANALYZER_OPERATIONLOG_HPP
 
 #include <vector>
+#include <variant>
+
+#include <nlohmann/json.hpp>
 
 struct OperationLog
 {
-  std::string operation;
+  struct IEntry
-  unsigned int line;
+  {
-  std::string operand_lhs;
+    [[nodiscard]] virtual nlohmann::json toJson() const = 0;
-  std::string operand_rhs;
+  };
-  std::string operand_result;
+
-  bool is_fallthrough;
+  struct FunctionCall : IEntry
-  std::vector<int> current_for_loops;
+  {
+    static constexpr char TYPE_NAME[] = "function_call";
+
+    std::string function_name;
+    std::string call_result_type;
+
+    [[nodiscard]] nlohmann::json toJson() const override;
+  };
+
+  struct BasicOperation : IEntry
+  {
+    static constexpr char TYPE_NAME[] = "basic_operation";
+
+    std::string operation_name;
+    std::string type_lhs;
+    std::string type_rhs;
+    std::string type_result;
+
+    [[nodiscard]] nlohmann::json toJson() const override;
+  };
+
+  unsigned int line = 0;
+  int branch_number = 0;
+
+  std::string entry_type;
+  std::unique_ptr<IEntry> entry;
+
+  OperationLog() = default;
+  OperationLog(const OperationLog&) = delete;
+  OperationLog(OperationLog&&) = default;
+
+  void DecodeEntry(const nlohmann::json& j);
 };
 
 class IOperationOutput
@@ -23,33 +57,58 @@ class IOperationOutput
 public:
   virtual ~IOperationOutput() = default;
 
-  virtual void pushOperation(const std::string& filename, const OperationLog& op) = 0;
+  virtual void pushOperation(const std::string& filename, OperationLog&& op) = 0;
 };
 
-#include <nlohmann/json.hpp>
-
 inline void to_json(nlohmann::json& j, const OperationLog& l)
 {
   j = nlohmann::json{
-          {"operation", l.operation},
           {"line", l.line},
-          {"operand_lhs", l.operand_lhs},
+          {"entry_type", l.entry_type},
-          {"operand_rhs", l.operand_rhs},
+          {"entry", l.entry->toJson()},
-          {"operand_result", l.operand_result},
+          {"branch_number", l.branch_number}
-          {"is_fallthrough", l.is_fallthrough},
-          {"current_for_loops", l.current_for_loops}
   };
 }
 
 inline void from_json(const nlohmann::json& j, OperationLog& l)
 {
-  j.at("operation").get_to(l.operation);
   j.at("line").get_to(l.line);
-  j.at("operand_lhs").get_to(l.operand_lhs);
+  j.at("entry_type").get_to(l.entry_type);
-  j.at("operand_rhs").get_to(l.operand_rhs);
+  l.DecodeEntry(j["entry"]);
-  j.at("operand_result").get_to(l.operand_result);
+
-  j.at("is_fallthrough").get_to(l.is_fallthrough);
+  j.at("branch_number").get_to(l.branch_number);
-  j.at("current_for_loops").get_to(l.current_for_loops);
+}
+
+inline void to_json(nlohmann::json& j, const OperationLog::BasicOperation& bo)
+{
+  j = nlohmann::json{
+          {"operation_name", bo.operation_name},
+          {"type_lhs", bo.type_lhs},
+          {"type_rhs", bo.type_rhs},
+          {"type_result", bo.type_result}
+  };
+}
+
+inline void from_json(const nlohmann::json& j, OperationLog::BasicOperation& bo)
+{
+  j.at("operation_name").get_to(bo.operation_name);
+  j.at("type_lhs").get_to(bo.type_lhs);
+  j.at("type_rhs").get_to(bo.type_rhs);
+  j.at("type_result").get_to(bo.type_result);
+}
+
+inline void to_json(nlohmann::json& j, const OperationLog::FunctionCall& fcall)
+{
+  j = nlohmann::json{
+          {"function_name", fcall.function_name},
+          {"call_result_type", fcall.call_result_type}
+  };
+}
+
+inline void from_json(const nlohmann::json& j, OperationLog::FunctionCall& fcall)
+{
+  j.at("function_name").get_to(fcall.function_name);
+  j.at("call_result_type").get_to(fcall.call_result_type);
 }
 
 #endif //C_ANALYZER_OPERATIONLOG_HPP

op-finder/OperationStorage.cpp

@@ -18,14 +18,19 @@ OperationStorage::~OperationStorage()
   _dumpToFile();
 }
 
-void OperationStorage::pushOperation(const std::string& filename, const OperationLog& op)
+void OperationStorage::enablePrettyPrint()
+{
+  _pretty_print = true;
+}
+
+void OperationStorage::pushOperation(const std::string& filename, OperationLog&& op)
 {
   auto it = _operations.find(filename);
 
   if (it == _operations.end())
-    it = _operations.insert({ filename, {} }).first;
+    it = _operations.emplace(filename, std::vector<OperationLog>()).first;
 
-  it->second.push_back(op);
+  it->second.emplace_back(std::move(op));
 }
 
 const std::unordered_map<std::string, std::vector<OperationLog>>& OperationStorage::getOperations() const
@@ -39,5 +44,8 @@ void OperationStorage::_dumpToFile()
 
   std::ofstream file(_output_filename);
 
-  file << json;
+  if (_pretty_print)
+    file << std::setw(4) << json;
+  else
+    file << json;
 }

op-finder/OperationStorage.hpp

@@ -20,12 +20,15 @@ public:
   explicit OperationStorage(const std::string& output_filename);
   ~OperationStorage() override;
 
-  void pushOperation(const std::string& filename, const OperationLog& op) override;
+  void enablePrettyPrint();
+  void pushOperation(const std::string& filename, OperationLog&& op) override;
   [[nodiscard]] const std::unordered_map<std::string, std::vector<OperationLog>>& getOperations() const;
 private:
   std::unordered_map<std::string, std::vector<OperationLog>> _operations;
   std::string _output_filename;
 
+  bool _pretty_print = false;
+
   void _dumpToFile();
 };
 

op-finder/main.cpp

@@ -24,6 +24,8 @@ static cl::opt<std::string> OutputFile("o", cl::desc("File to output the JSON to
 static cl::opt<std::string> RootDirectory("r", cl::desc("The root directory of the source files."),
                                           cl::cat(MyToolCategory));
 
+static cl::opt<bool> PrettyPrint("pretty", cl::desc("Pretty-print the output JSON."));
+
 // CommonOptionsParser declares HelpMessage with a description of the common
 // command-line options related to the compilation database and input files.
 // It's nice to have this help message in all tools.
@@ -50,6 +52,9 @@ int main(int argc, const char** argv)
 
   OperationStorage storage(OutputFile.getValue());
 
+  if (PrettyPrint.getValue())
+    storage.enablePrettyPrint();
+
   OperationFinder op_finder(&storage);
 
 #if 0