aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/clang14/tools/extra/clang-tidy/bugprone/AssertSideEffectCheck.cpp
blob: eba6b29f56af9a6a30e5cfa5a155da432e752e3f (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
//===--- AssertSideEffectCheck.cpp - clang-tidy ---------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//

#include "AssertSideEffectCheck.h"
#include "../utils/Matchers.h"
#include "../utils/OptionsUtils.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Lex/Lexer.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Casting.h"
#include <algorithm>
#include <string>

using namespace clang::ast_matchers;

namespace clang {
namespace tidy {
namespace bugprone {

namespace {

AST_MATCHER_P2(Expr, hasSideEffect, bool, CheckFunctionCalls,
               clang::ast_matchers::internal::Matcher<NamedDecl>,
               IgnoredFunctionsMatcher) {
  const Expr *E = &Node;

  if (const auto *Op = dyn_cast<UnaryOperator>(E)) {
    UnaryOperator::Opcode OC = Op->getOpcode();
    return OC == UO_PostInc || OC == UO_PostDec || OC == UO_PreInc ||
           OC == UO_PreDec;
  }

  if (const auto *Op = dyn_cast<BinaryOperator>(E)) {
    return Op->isAssignmentOp();
  }

  if (const auto *OpCallExpr = dyn_cast<CXXOperatorCallExpr>(E)) {
    OverloadedOperatorKind OpKind = OpCallExpr->getOperator();
    return OpKind == OO_Equal || OpKind == OO_PlusEqual ||
           OpKind == OO_MinusEqual || OpKind == OO_StarEqual ||
           OpKind == OO_SlashEqual || OpKind == OO_AmpEqual ||
           OpKind == OO_PipeEqual || OpKind == OO_CaretEqual ||
           OpKind == OO_LessLessEqual || OpKind == OO_GreaterGreaterEqual ||
           OpKind == OO_PlusPlus || OpKind == OO_MinusMinus ||
           OpKind == OO_PercentEqual || OpKind == OO_New ||
           OpKind == OO_Delete || OpKind == OO_Array_New ||
           OpKind == OO_Array_Delete;
  }

  if (const auto *CExpr = dyn_cast<CallExpr>(E)) {
    bool Result = CheckFunctionCalls;
    if (const auto *FuncDecl = CExpr->getDirectCallee()) {
      if (FuncDecl->getDeclName().isIdentifier() &&
          IgnoredFunctionsMatcher.matches(*FuncDecl, Finder,
                                          Builder)) // exceptions come here
        Result = false;
      else if (const auto *MethodDecl = dyn_cast<CXXMethodDecl>(FuncDecl))
        Result &= !MethodDecl->isConst();
    }
    return Result;
  }

  return isa<CXXNewExpr>(E) || isa<CXXDeleteExpr>(E) || isa<CXXThrowExpr>(E);
}

} // namespace

AssertSideEffectCheck::AssertSideEffectCheck(StringRef Name,
                                             ClangTidyContext *Context)
    : ClangTidyCheck(Name, Context),
      CheckFunctionCalls(Options.get("CheckFunctionCalls", false)),
      RawAssertList(Options.get("AssertMacros", "assert,NSAssert,NSCAssert")),
      IgnoredFunctions(utils::options::parseStringList(
          "__builtin_expect;" + Options.get("IgnoredFunctions", ""))) {
  StringRef(RawAssertList).split(AssertMacros, ",", -1, false);
}

// The options are explained in AssertSideEffectCheck.h.
void AssertSideEffectCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
  Options.store(Opts, "CheckFunctionCalls", CheckFunctionCalls);
  Options.store(Opts, "AssertMacros", RawAssertList);
  Options.store(Opts, "IgnoredFunctions",
                utils::options::serializeStringList(IgnoredFunctions));
}

void AssertSideEffectCheck::registerMatchers(MatchFinder *Finder) {
  auto IgnoredFunctionsMatcher =
      matchers::matchesAnyListedName(IgnoredFunctions);

  auto DescendantWithSideEffect =
      traverse(TK_AsIs, hasDescendant(expr(hasSideEffect(
                            CheckFunctionCalls, IgnoredFunctionsMatcher))));
  auto ConditionWithSideEffect = hasCondition(DescendantWithSideEffect);
  Finder->addMatcher(
      stmt(
          anyOf(conditionalOperator(ConditionWithSideEffect),
                ifStmt(ConditionWithSideEffect),
                unaryOperator(hasOperatorName("!"),
                              hasUnaryOperand(unaryOperator(
                                  hasOperatorName("!"),
                                  hasUnaryOperand(DescendantWithSideEffect))))))
          .bind("condStmt"),
      this);
}

void AssertSideEffectCheck::check(const MatchFinder::MatchResult &Result) {
  const SourceManager &SM = *Result.SourceManager;
  const LangOptions LangOpts = getLangOpts();
  SourceLocation Loc = Result.Nodes.getNodeAs<Stmt>("condStmt")->getBeginLoc();

  StringRef AssertMacroName;
  while (Loc.isValid() && Loc.isMacroID()) {
    StringRef MacroName = Lexer::getImmediateMacroName(Loc, SM, LangOpts);

    // Check if this macro is an assert.
    if (llvm::is_contained(AssertMacros, MacroName)) {
      AssertMacroName = MacroName;
      break;
    }
    Loc = SM.getImmediateMacroCallerLoc(Loc);
  }
  if (AssertMacroName.empty())
    return;

  diag(Loc, "side effect in %0() condition discarded in release builds")
      << AssertMacroName;
}

} // namespace bugprone
} // namespace tidy
} // namespace clang