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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* Based on LLVM/Clang.
*
* This file is distributed under the University of Illinois Open Source
* License. See LICENSE.TXT for details.
*
*/
#ifndef LO_CLANG_SHARED_PLUGINS
#include <cassert>
#include <string>
#include <iostream>
#include <fstream>
#include <set>
#include <unordered_set>
#include "plugin.hxx"
#include "check.hxx"
/*
Look for places where we are using cow_wrapper, but we are calling a const method on the impl object
with a non-const pointer, which means we will unnecessarily trigger a copy.
*/
namespace
{
class Cow_Wrapper : public loplugin::FilteringPlugin<Cow_Wrapper>
{
public:
explicit Cow_Wrapper(loplugin::InstantiationData const& data)
: FilteringPlugin(data)
{
}
bool shouldVisitTemplateInstantiations() const { return true; }
virtual bool preRun() override { return true; }
virtual void run() override
{
if (preRun())
TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
}
bool VisitCXXMemberCallExpr(const CXXMemberCallExpr*);
};
bool Cow_Wrapper::VisitCXXMemberCallExpr(const CXXMemberCallExpr* memberCallExpr)
{
if (ignoreLocation(memberCallExpr))
return true;
auto methodDecl = memberCallExpr->getMethodDecl();
if (!methodDecl || !methodDecl->isConst())
return true;
auto expr = memberCallExpr->getImplicitObjectArgument()->IgnoreImplicit()->IgnoreParens();
auto operatorCallExpr = dyn_cast<CXXOperatorCallExpr>(expr);
if (operatorCallExpr && operatorCallExpr->getOperator() == OO_Arrow)
{
auto arrowMethodDecl = dyn_cast_or_null<CXXMethodDecl>(operatorCallExpr->getDirectCallee());
if (!arrowMethodDecl)
return true;
if (arrowMethodDecl->isConst())
return true;
auto dc = loplugin::DeclCheck(arrowMethodDecl->getParent())
.Class("cow_wrapper")
.Namespace("o3tl")
.GlobalNamespace();
if (!dc)
return true;
}
else if (operatorCallExpr)
{
auto methodDecl2 = dyn_cast_or_null<CXXMethodDecl>(operatorCallExpr->getDirectCallee());
if (!methodDecl2)
return true;
auto dc = loplugin::DeclCheck(methodDecl2->getParent())
.Class("cow_wrapper")
.Namespace("o3tl")
.GlobalNamespace();
if (!dc)
return true;
}
else if (auto callExpr = dyn_cast<CallExpr>(expr))
{
if (!isa<ImplicitCastExpr>(callExpr->getCallee())) // std::as_const shows up as this
return true;
if (callExpr->getNumArgs() < 1)
return true;
auto arg0 = dyn_cast<CXXOperatorCallExpr>(callExpr->getArg(0));
if (!arg0)
return true;
auto starMethodDecl = dyn_cast_or_null<CXXMethodDecl>(arg0->getDirectCallee());
if (!starMethodDecl)
return true;
auto dc = loplugin::DeclCheck(starMethodDecl->getParent())
.Class("cow_wrapper")
.Namespace("o3tl")
.GlobalNamespace();
if (!dc)
return true;
}
else
return true;
report(DiagnosticsEngine::Warning,
"calling const method on o3tl::cow_wrapper impl class via non-const pointer, rather use "
"std::as_const to prevent triggering an unnecessary copy",
memberCallExpr->getBeginLoc())
<< memberCallExpr->getSourceRange();
return true;
}
loplugin::Plugin::Registration<Cow_Wrapper> cow_wrapper("cow_wrapper", true);
} // namespace
#endif // LO_CLANG_SHARED_PLUGINS
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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