xref: /freebsd/contrib/llvm-project/clang/lib/StaticAnalyzer/Checkers/TraversalChecker.cpp (revision 02e9120893770924227138ba49df1edb3896112a)
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 
36 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 
54 void TraversalDumper::checkBeginFunction(CheckerContext &C) const {
55   llvm::outs() << "--BEGIN FUNCTION--\n";
56 }
57 
58 void TraversalDumper::checkEndFunction(const ReturnStmt *RS,
59                                        CheckerContext &C) const {
60   llvm::outs() << "--END FUNCTION--\n";
61 }
62 
63 void ento::registerTraversalDumper(CheckerManager &mgr) {
64   mgr.registerChecker<TraversalDumper>();
65 }
66 
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 
82 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 
95 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 
115 void ento::registerCallDumper(CheckerManager &mgr) {
116   mgr.registerChecker<CallDumper>();
117 }
118 
119 bool ento::shouldRegisterCallDumper(const CheckerManager &mgr) {
120   return true;
121 }
122