File: FasterStringFindCheck.cpp

package info (click to toggle)
llvm-toolchain-6.0 1%3A6.0.1-10
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 598,080 kB
  • sloc: cpp: 3,046,253; ansic: 595,057; asm: 271,965; python: 128,926; objc: 106,554; sh: 21,906; lisp: 10,191; pascal: 6,094; ml: 5,544; perl: 5,265; makefile: 2,227; cs: 2,027; xml: 686; php: 212; csh: 117
file content (104 lines) | stat: -rw-r--r-- 3,631 bytes parent folder | download | duplicates (4)
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
//===--- FasterStringFindCheck.cpp - clang-tidy----------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "FasterStringFindCheck.h"
#include "../utils/OptionsUtils.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "llvm/ADT/Optional.h"
#include "llvm/Support/raw_ostream.h"

using namespace clang::ast_matchers;

namespace clang {
namespace tidy {
namespace performance {

namespace {

llvm::Optional<std::string> MakeCharacterLiteral(const StringLiteral *Literal) {
  std::string Result;
  {
    llvm::raw_string_ostream OS(Result);
    Literal->outputString(OS);
  }
  // Now replace the " with '.
  auto pos = Result.find_first_of('"');
  if (pos == Result.npos)
    return llvm::None;
  Result[pos] = '\'';
  pos = Result.find_last_of('"');
  if (pos == Result.npos)
    return llvm::None;
  Result[pos] = '\'';
  return Result;
}

AST_MATCHER_FUNCTION(ast_matchers::internal::Matcher<Expr>,
                     hasSubstitutedType) {
  return hasType(qualType(anyOf(substTemplateTypeParmType(),
                                hasDescendant(substTemplateTypeParmType()))));
}

} // namespace

FasterStringFindCheck::FasterStringFindCheck(StringRef Name,
                                             ClangTidyContext *Context)
    : ClangTidyCheck(Name, Context),
      StringLikeClasses(utils::options::parseStringList(
          Options.get("StringLikeClasses", "std::basic_string"))) {}

void FasterStringFindCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
  Options.store(Opts, "StringLikeClasses",
                utils::options::serializeStringList(StringLikeClasses));
}

void FasterStringFindCheck::registerMatchers(MatchFinder *Finder) {
  if (!getLangOpts().CPlusPlus)
    return;

  const auto SingleChar =
      expr(ignoringParenCasts(stringLiteral(hasSize(1)).bind("literal")));
  const auto StringFindFunctions =
      hasAnyName("find", "rfind", "find_first_of", "find_first_not_of",
                 "find_last_of", "find_last_not_of");

  Finder->addMatcher(
      cxxMemberCallExpr(
          callee(functionDecl(StringFindFunctions).bind("func")),
          anyOf(argumentCountIs(1), argumentCountIs(2)),
          hasArgument(0, SingleChar),
          on(expr(
              hasType(hasUnqualifiedDesugaredType(recordType(hasDeclaration(
                  recordDecl(hasAnyName(SmallVector<StringRef, 4>(
                      StringLikeClasses.begin(), StringLikeClasses.end()))))))),
              unless(hasSubstitutedType())))),
      this);
}

void FasterStringFindCheck::check(const MatchFinder::MatchResult &Result) {
  const auto *Literal = Result.Nodes.getNodeAs<StringLiteral>("literal");
  const auto *FindFunc = Result.Nodes.getNodeAs<FunctionDecl>("func");

  auto Replacement = MakeCharacterLiteral(Literal);
  if (!Replacement)
    return;

  diag(Literal->getLocStart(), "%0 called with a string literal consisting of "
                               "a single character; consider using the more "
                               "effective overload accepting a character")
      << FindFunc << FixItHint::CreateReplacement(
                         CharSourceRange::getTokenRange(Literal->getLocStart(),
                                                        Literal->getLocEnd()),
                         *Replacement);
}

} // namespace performance
} // namespace tidy
} // namespace clang