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
22 using namespace clang;
23 using namespace ento;
24
25 namespace {
26 class TraversalDumper : public Checker< check::BranchCondition,
27 check::BeginFunction,
28 check::EndFunction > {
29 public:
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
checkBranchCondition(const Stmt * Condition,CheckerContext & C) const36 void 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
checkBeginFunction(CheckerContext & C) const54 void TraversalDumper::checkBeginFunction(CheckerContext &C) const {
55 llvm::outs() << "--BEGIN FUNCTION--\n";
56 }
57
checkEndFunction(const ReturnStmt * RS,CheckerContext & C) const58 void TraversalDumper::checkEndFunction(const ReturnStmt *RS,
59 CheckerContext &C) const {
60 llvm::outs() << "--END FUNCTION--\n";
61 }
62
registerTraversalDumper(CheckerManager & mgr)63 void ento::registerTraversalDumper(CheckerManager &mgr) {
64 mgr.registerChecker<TraversalDumper>();
65 }
66
shouldRegisterTraversalDumper(const CheckerManager & mgr)67 bool ento::shouldRegisterTraversalDumper(const CheckerManager &mgr) {
68 return true;
69 }
70
71 //------------------------------------------------------------------------------
72
73 namespace {
74 class CallDumper : public Checker< check::PreCall,
75 check::PostCall > {
76 public:
77 void checkPreCall(const CallEvent &Call, CheckerContext &C) const;
78 void checkPostCall(const CallEvent &Call, CheckerContext &C) const;
79 };
80 }
81
checkPreCall(const CallEvent & Call,CheckerContext & C) const82 void 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
checkPostCall(const CallEvent & Call,CheckerContext & C) const95 void 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
registerCallDumper(CheckerManager & mgr)115 void ento::registerCallDumper(CheckerManager &mgr) {
116 mgr.registerChecker<CallDumper>();
117 }
118
shouldRegisterCallDumper(const CheckerManager & mgr)119 bool ento::shouldRegisterCallDumper(const CheckerManager &mgr) {
120 return true;
121 }
122