aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/clang16/lib/StaticAnalyzer/Checkers/DebugIteratorModeling.cpp
blob: d05298b42c55cd0e54c4505231e45bea8575f207 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
//===-- DebugIteratorModeling.cpp ---------------------------------*- C++ -*--//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Defines a checker for debugging iterator modeling.
//
//===----------------------------------------------------------------------===//

#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
#include "clang/StaticAnalyzer/Core/Checker.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/CallDescription.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"

#include "Iterator.h"

using namespace clang;
using namespace ento;
using namespace iterator;

namespace {

class DebugIteratorModeling
  : public Checker<eval::Call> {

  std::unique_ptr<BugType> DebugMsgBugType;

  template <typename Getter>
  void analyzerIteratorDataField(const CallExpr *CE, CheckerContext &C,
                                 Getter get, SVal Default) const;
  void analyzerIteratorPosition(const CallExpr *CE, CheckerContext &C) const;
  void analyzerIteratorContainer(const CallExpr *CE, CheckerContext &C) const;
  void analyzerIteratorValidity(const CallExpr *CE, CheckerContext &C) const;
  ExplodedNode *reportDebugMsg(llvm::StringRef Msg, CheckerContext &C) const;

  typedef void (DebugIteratorModeling::*FnCheck)(const CallExpr *,
                                                 CheckerContext &) const;

  CallDescriptionMap<FnCheck> Callbacks = {
      {{{"clang_analyzer_iterator_position"}, 1},
       &DebugIteratorModeling::analyzerIteratorPosition},
      {{{"clang_analyzer_iterator_container"}, 1},
       &DebugIteratorModeling::analyzerIteratorContainer},
      {{{"clang_analyzer_iterator_validity"}, 1},
       &DebugIteratorModeling::analyzerIteratorValidity},
  };

public:
  DebugIteratorModeling();

  bool evalCall(const CallEvent &Call, CheckerContext &C) const;
};

} //namespace

DebugIteratorModeling::DebugIteratorModeling() {
  DebugMsgBugType.reset(
      new BugType(this, "Checking analyzer assumptions", "debug",
                  /*SuppressOnSink=*/true));
}

bool DebugIteratorModeling::evalCall(const CallEvent &Call,
                                     CheckerContext &C) const {
  const auto *CE = dyn_cast_or_null<CallExpr>(Call.getOriginExpr());
  if (!CE)
    return false;

  const FnCheck *Handler = Callbacks.lookup(Call);
  if (!Handler)
    return false;

  (this->**Handler)(CE, C);
  return true;
}

template <typename Getter>
void DebugIteratorModeling::analyzerIteratorDataField(const CallExpr *CE,
                                                      CheckerContext &C,
                                                      Getter get,
                                                      SVal Default) const {
  if (CE->getNumArgs() == 0) {
    reportDebugMsg("Missing iterator argument", C);
    return;
  }

  auto State = C.getState();
  SVal V = C.getSVal(CE->getArg(0));
  const auto *Pos = getIteratorPosition(State, V);
  if (Pos) {
    State = State->BindExpr(CE, C.getLocationContext(), get(Pos));
  } else {
    State = State->BindExpr(CE, C.getLocationContext(), Default);
  }
  C.addTransition(State);
}

void DebugIteratorModeling::analyzerIteratorPosition(const CallExpr *CE,
                                                     CheckerContext &C) const {
  auto &BVF = C.getSValBuilder().getBasicValueFactory();
  analyzerIteratorDataField(CE, C, [](const IteratorPosition *P) {
      return nonloc::SymbolVal(P->getOffset());
    }, nonloc::ConcreteInt(BVF.getValue(llvm::APSInt::get(0))));
}

void DebugIteratorModeling::analyzerIteratorContainer(const CallExpr *CE,
                                                      CheckerContext &C) const {
  auto &BVF = C.getSValBuilder().getBasicValueFactory();
  analyzerIteratorDataField(CE, C, [](const IteratorPosition *P) {
      return loc::MemRegionVal(P->getContainer());
    }, loc::ConcreteInt(BVF.getValue(llvm::APSInt::get(0))));
}

void DebugIteratorModeling::analyzerIteratorValidity(const CallExpr *CE,
                                                     CheckerContext &C) const {
  auto &BVF = C.getSValBuilder().getBasicValueFactory();
  analyzerIteratorDataField(CE, C, [&BVF](const IteratorPosition *P) {
      return
        nonloc::ConcreteInt(BVF.getValue(llvm::APSInt::get((P->isValid()))));
    }, nonloc::ConcreteInt(BVF.getValue(llvm::APSInt::get(0))));
}

ExplodedNode *DebugIteratorModeling::reportDebugMsg(llvm::StringRef Msg,
                                                    CheckerContext &C) const {
  ExplodedNode *N = C.generateNonFatalErrorNode();
  if (!N)
    return nullptr;

  auto &BR = C.getBugReporter();
  BR.emitReport(std::make_unique<PathSensitiveBugReport>(*DebugMsgBugType,
                                                         Msg, N));
  return N;
}

void ento::registerDebugIteratorModeling(CheckerManager &mgr) {
  mgr.registerChecker<DebugIteratorModeling>();
}

bool ento::shouldRegisterDebugIteratorModeling(const CheckerManager &mgr) {
  return true;
}