10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 #include "clang/Lex/Lexer.h"
18 namespace performance {
21 if (
const auto *LeftRefType = Left->getAs<ReferenceType>())
22 Left = LeftRefType->getPointeeType();
23 if (
const auto *RightRefType = Right->getAs<ReferenceType>())
24 Right = RightRefType->getPointeeType();
25 return Left->getCanonicalTypeUnqualified() ==
26 Right->getCanonicalTypeUnqualified();
29 void InefficientAlgorithmCheck::registerMatchers(MatchFinder *Finder) {
30 const auto Algorithms =
31 hasAnyName(
"::std::find",
"::std::count",
"::std::equal_range",
32 "::std::lower_bound",
"::std::upper_bound");
33 const auto ContainerMatcher = classTemplateSpecializationDecl(hasAnyName(
34 "::std::set",
"::std::map",
"::std::multiset",
"::std::multimap",
35 "::std::unordered_set",
"::std::unordered_map",
36 "::std::unordered_multiset",
"::std::unordered_multimap"));
38 const auto Matcher = traverse(
39 ast_type_traits::TK_AsIs,
41 callee(functionDecl(Algorithms)),
43 0, cxxConstructExpr(has(ignoringParenImpCasts(cxxMemberCallExpr(
44 callee(cxxMethodDecl(hasName(
"begin"))),
46 hasDeclaration(decl().bind(
"IneffContObj")),
47 anyOf(hasType(ContainerMatcher.bind(
"IneffCont")),
49 ContainerMatcher.bind(
"IneffContPtr")))))
50 .bind(
"IneffContExpr"))))))),
52 1, cxxConstructExpr(has(ignoringParenImpCasts(cxxMemberCallExpr(
53 callee(cxxMethodDecl(hasName(
"end"))),
55 hasDeclaration(equalsBoundNode(
"IneffContObj"))))))))),
56 hasArgument(2, expr().bind(
"AlgParam")),
57 unless(isInTemplateInstantiation()))
60 Finder->addMatcher(Matcher,
this);
63 void InefficientAlgorithmCheck::check(
const MatchFinder::MatchResult &Result) {
64 const auto *AlgCall = Result.Nodes.getNodeAs<CallExpr>(
"IneffAlg");
65 const auto *IneffCont =
66 Result.Nodes.getNodeAs<ClassTemplateSpecializationDecl>(
"IneffCont");
67 bool PtrToContainer =
false;
70 Result.Nodes.getNodeAs<ClassTemplateSpecializationDecl>(
"IneffContPtr");
71 PtrToContainer =
true;
73 const llvm::StringRef IneffContName = IneffCont->getName();
74 const bool Unordered =
75 IneffContName.find(
"unordered") != llvm::StringRef::npos;
76 const bool Maplike = IneffContName.find(
"map") != llvm::StringRef::npos;
80 QualType ValueType = AlgCall->getArg(2)->getType();
82 IneffCont->getTemplateArgs()[0].getAsType().getCanonicalType();
86 if (AlgCall->getNumArgs() == 4 && !Unordered) {
87 const Expr *Arg = AlgCall->getArg(3);
88 const QualType AlgCmp =
89 Arg->getType().getUnqualifiedType().getCanonicalType();
90 const unsigned CmpPosition =
91 (IneffContName.find(
"map") == llvm::StringRef::npos) ? 1 : 2;
92 const QualType ContainerCmp = IneffCont->getTemplateArgs()[CmpPosition]
96 if (AlgCmp != ContainerCmp) {
97 diag(Arg->getBeginLoc(),
98 "different comparers used in the algorithm and the container");
103 const auto *AlgDecl = AlgCall->getDirectCallee();
107 if (Unordered && AlgDecl->getName().find(
"bound") != llvm::StringRef::npos)
110 const auto *AlgParam = Result.Nodes.getNodeAs<Expr>(
"AlgParam");
111 const auto *IneffContExpr = Result.Nodes.getNodeAs<Expr>(
"IneffContExpr");
114 SourceManager &SM = *Result.SourceManager;
115 LangOptions LangOpts = getLangOpts();
117 CharSourceRange CallRange =
118 CharSourceRange::getTokenRange(AlgCall->getSourceRange());
131 if (SM.isMacroArgExpansion(CallRange.getBegin()) &&
132 SM.isMacroArgExpansion(CallRange.getEnd())) {
133 CallRange.setBegin(SM.getSpellingLoc(CallRange.getBegin()));
134 CallRange.setEnd(SM.getSpellingLoc(CallRange.getEnd()));
137 if (!CallRange.getBegin().isMacroID() && !Maplike && CompatibleTypes) {
138 StringRef ContainerText = Lexer::getSourceText(
139 CharSourceRange::getTokenRange(IneffContExpr->getSourceRange()), SM,
141 StringRef ParamText = Lexer::getSourceText(
142 CharSourceRange::getTokenRange(AlgParam->getSourceRange()), SM,
144 std::string ReplacementText =
145 (llvm::Twine(ContainerText) + (PtrToContainer ?
"->" :
".") +
146 AlgDecl->getName() +
"(" + ParamText +
")")
148 Hint = FixItHint::CreateReplacement(CallRange, ReplacementText);
151 diag(AlgCall->getBeginLoc(),
152 "this STL algorithm call should be replaced with a container method")