path: root/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp

// BugReporterVisitors.cpp - Helpers for reporting bugs -----------*- C++ -*--//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//  This file defines a set of BugReporter "visitors" which can be used to
//  enhance the diagnostics reported for a bug.
//
//===----------------------------------------------------------------------===//
#include "clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprObjC.h"
#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
#include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/ExplodedGraph.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/raw_ostream.h"

using namespace clang;
using namespace ento;

//===----------------------------------------------------------------------===//
// Utility functions.
//===----------------------------------------------------------------------===//

bool bugreporter::isDeclRefExprToReference(const Expr *E) {
  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
    return DRE->getDecl()->getType()->isReferenceType();
  }
  return false;
}

const Expr *bugreporter::getDerefExpr(const Stmt *S) {
  // Pattern match for a few useful cases (do something smarter later):
  //   a[0], p->f, *p
  const Expr *E = dyn_cast<Expr>(S);
  if (!E)
    return 0;
  E = E->IgnoreParenCasts();

  while (true) {
    if (const BinaryOperator *B = dyn_cast<BinaryOperator>(E)) {
      assert(B->isAssignmentOp());
      E = B->getLHS()->IgnoreParenCasts();
      continue;
    }
    else if (const UnaryOperator *U = dyn_cast<UnaryOperator>(E)) {
      if (U->getOpcode() == UO_Deref)
        return U->getSubExpr()->IgnoreParenCasts();
    }
    else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
      if (ME->isArrow() || isDeclRefExprToReference(ME->getBase())) {
        return ME->getBase()->IgnoreParenCasts();
      }
    }
    else if (const ObjCIvarRefExpr *IvarRef = dyn_cast<ObjCIvarRefExpr>(E)) {
      return IvarRef->getBase()->IgnoreParenCasts();
    }
    else if (const ArraySubscriptExpr *AE = dyn_cast<ArraySubscriptExpr>(E)) {
      return AE->getBase();
    }
    break;
  }

  return NULL;
}

const Stmt *bugreporter::GetDenomExpr(const ExplodedNode *N) {
  const Stmt *S = N->