1//== TraversalChecker.cpp -------------------------------------- -*- C++ -*--=//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// These checkers print various aspects of the ExprEngine's traversal of the CFG
10// as it builds the ExplodedGraph.
11//
12//===----------------------------------------------------------------------===//
13#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
14#include "clang/AST/ParentMap.h"
15#include "clang/AST/StmtObjC.h"
16#include "clang/StaticAnalyzer/Core/Checker.h"
17#include "clang/StaticAnalyzer/Core/CheckerManager.h"
18#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
19#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
20#include "llvm/Support/raw_ostream.h"
21
22using namespace clang;
23using namespace ento;
24
25namespace {
26class TraversalDumper : public Checker< check::BranchCondition,
27                                        check::BeginFunction,
28                                        check::EndFunction > {
29public:
30  void checkBranchCondition(const Stmt *Condition, CheckerContext &C) const;
31  void checkBeginFunction(CheckerContext &C) const;
32  void checkEndFunction(const ReturnStmt *RS, CheckerContext &C) const;
33};
34}
35
36void TraversalDumper::checkBranchCondition(const Stmt *Condition,
37                                           CheckerContext &C) const {
38  // Special-case Objective-C's for-in loop, which uses the entire loop as its
39  // condition. We just print the collection expression.
40  const Stmt *Parent = dyn_cast<ObjCForCollectionStmt>(Condition);
41  if (!Parent) {
42    const ParentMap &Parents = C.getLocationContext()->getParentMap();
43    Parent = Parents.getParent(Condition);
44  }
45
46  // It is mildly evil to print directly to llvm::outs() rather than emitting
47  // warnings, but this ensures things do not get filtered out by the rest of
48  // the static analyzer machinery.
49  SourceLocation Loc = Parent->getBeginLoc();
50  llvm::outs() << C.getSourceManager().getSpellingLineNumber(Loc) << " "
51               << Parent->getStmtClassName() << "\n";
52}
53
54void TraversalDumper::checkBeginFunction(CheckerContext &C) const {
55  llvm::outs() << "--BEGIN FUNCTION--\n";
56}
57
58void TraversalDumper::checkEndFunction(const ReturnStmt *RS,
59                                       CheckerContext &C) const {
60  llvm::outs() << "--END FUNCTION--\n";
61}
62
63void ento::registerTraversalDumper(CheckerManager &mgr) {
64  mgr.registerChecker<TraversalDumper>();
65}
66
67bool ento::shouldRegisterTraversalDumper(const LangOptions &LO) {
68  return true;
69}
70
71//------------------------------------------------------------------------------
72
73namespace {
74class CallDumper : public Checker< check::PreCall,
75                                   check::PostCall > {
76public:
77  void checkPreCall(const CallEvent &Call, CheckerContext &C) const;
78  void checkPostCall(const CallEvent &Call, CheckerContext &C) const;
79};
80}
81
82void CallDumper::checkPreCall(const CallEvent &Call, CheckerContext &C) const {
83  unsigned Indentation = 0;
84  for (const LocationContext *LC = C.getLocationContext()->getParent();
85       LC != nullptr; LC = LC->getParent())
86    ++Indentation;
87
88  // It is mildly evil to print directly to llvm::outs() rather than emitting
89  // warnings, but this ensures things do not get filtered out by the rest of
90  // the static analyzer machinery.
91  llvm::outs().indent(Indentation);
92  Call.dump(llvm::outs());
93}
94
95void CallDumper::checkPostCall(const CallEvent &Call, CheckerContext &C) const {
96  const Expr *CallE = Call.getOriginExpr();
97  if (!CallE)
98    return;
99
100  unsigned Indentation = 0;
101  for (const LocationContext *LC = C.getLocationContext()->getParent();
102       LC != nullptr; LC = LC->getParent())
103    ++Indentation;
104
105  // It is mildly evil to print directly to llvm::outs() rather than emitting
106  // warnings, but this ensures things do not get filtered out by the rest of
107  // the static analyzer machinery.
108  llvm::outs().indent(Indentation);
109  if (Call.getResultType()->isVoidType())
110    llvm::outs() << "Returning void\n";
111  else
112    llvm::outs() << "Returning " << C.getSVal(CallE) << "\n";
113}
114
115void ento::registerCallDumper(CheckerManager &mgr) {
116  mgr.registerChecker<CallDumper>();
117}
118
119bool ento::shouldRegisterCallDumper(const LangOptions &LO) {
120  return true;
121}
122