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| //===--- NoexceptMoveConstructorCheck.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 "NoexceptMoveConstructorCheck.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/Tooling/FixIt.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
namespace performance {
void NoexceptMoveConstructorCheck::registerMatchers(MatchFinder *Finder) {
// Only register the matchers for C++11; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (!getLangOpts().CPlusPlus11)
return;
Finder->addMatcher(
cxxMethodDecl(anyOf(cxxConstructorDecl(), hasOverloadedOperatorName("=")),
unless(isImplicit()), unless(isDeleted()))
.bind("decl"),
this);
}
void NoexceptMoveConstructorCheck::check(
const MatchFinder::MatchResult &Result) {
if (const auto *Decl = Result.Nodes.getNodeAs<CXXMethodDecl>("decl")) {
StringRef MethodType = "assignment operator";
if (const auto *Ctor = dyn_cast<CXXConstructorDecl>(Decl)) {
if (!Ctor->isMoveConstructor())
return;
MethodType = "constructor";
} else if (!Decl->isMoveAssignmentOperator()) {
return;
}
const auto *ProtoType = Decl->getType()->getAs<FunctionProtoType>();
if (isUnresolvedExceptionSpec(ProtoType->getExceptionSpecType()))
return;
if (!isNoexceptExceptionSpec(ProtoType->getExceptionSpecType())) {
auto Diag =
diag(Decl->getLocation(), "move %0s should be marked noexcept")
<< MethodType;
// Add FixIt hints.
SourceManager &SM = *Result.SourceManager;
assert(Decl->getNumParams() > 0);
SourceLocation NoexceptLoc = Decl->getParamDecl(Decl->getNumParams() - 1)
->getSourceRange()
.getEnd();
if (NoexceptLoc.isValid())
NoexceptLoc = Lexer::findLocationAfterToken(
NoexceptLoc, tok::r_paren, SM, Result.Context->getLangOpts(), true);
if (NoexceptLoc.isValid())
Diag << FixItHint::CreateInsertion(NoexceptLoc, " noexcept ");
return;
}
// Don't complain about nothrow(false), but complain on nothrow(expr)
// where expr evaluates to false.
if (ProtoType->canThrow() == CT_Can) {
Expr *E = ProtoType->getNoexceptExpr();
E = E->IgnoreImplicit();
if (!isa<CXXBoolLiteralExpr>(E)) {
diag(E->getExprLoc(),
"noexcept specifier on the move %0 evaluates to 'false'")
<< MethodType;
}
}
}
}
} // namespace performance
} // namespace tidy
} // namespace clang
|