2dbd02b576
check for calls to constructors, and extend the list of types we check for unnecessary temporary creation Change-Id: Ia2c1f202b41ed6866779fff5343c821128033eec Reviewed-on: https://gerrit.libreoffice.org/63472 Tested-by: Jenkins Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
230 lines
9.6 KiB
C++
230 lines
9.6 KiB
C++
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
|
|
/*
|
|
* This file is part of the LibreOffice project.
|
|
*
|
|
* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
|
*/
|
|
|
|
#include "check.hxx"
|
|
#include "compat.hxx"
|
|
#include "plugin.hxx"
|
|
#include <iostream>
|
|
#include <fstream>
|
|
|
|
namespace
|
|
{
|
|
class RedundantFCast final : public loplugin::FilteringPlugin<RedundantFCast>
|
|
{
|
|
public:
|
|
explicit RedundantFCast(loplugin::InstantiationData const& data)
|
|
: FilteringPlugin(data)
|
|
{
|
|
}
|
|
|
|
bool TraverseFunctionDecl(FunctionDecl* functionDecl)
|
|
{
|
|
auto prev = m_CurrentFunctionDecl;
|
|
m_CurrentFunctionDecl = functionDecl;
|
|
auto rv = RecursiveASTVisitor<RedundantFCast>::TraverseFunctionDecl(functionDecl);
|
|
m_CurrentFunctionDecl = prev;
|
|
return rv;
|
|
}
|
|
|
|
bool VisitReturnStmt(ReturnStmt const* returnStmt)
|
|
{
|
|
if (ignoreLocation(returnStmt))
|
|
return true;
|
|
Expr const* expr = returnStmt->getRetValue();
|
|
if (!expr)
|
|
return true;
|
|
if (auto exprWithCleanups = dyn_cast<ExprWithCleanups>(expr))
|
|
expr = exprWithCleanups->getSubExpr();
|
|
if (auto cxxConstructExpr = dyn_cast<CXXConstructExpr>(expr))
|
|
{
|
|
if (cxxConstructExpr->getNumArgs() != 1)
|
|
return true;
|
|
expr = cxxConstructExpr->getArg(0);
|
|
}
|
|
if (auto materializeTemporaryExpr = dyn_cast<MaterializeTemporaryExpr>(expr))
|
|
expr = materializeTemporaryExpr->GetTemporaryExpr();
|
|
auto cxxFunctionalCastExpr = dyn_cast<CXXFunctionalCastExpr>(expr);
|
|
if (!cxxFunctionalCastExpr)
|
|
return true;
|
|
auto const t1 = cxxFunctionalCastExpr->getTypeAsWritten();
|
|
auto const t2 = compat::getSubExprAsWritten(cxxFunctionalCastExpr)->getType();
|
|
if (t1.getCanonicalType().getTypePtr() != t2.getCanonicalType().getTypePtr())
|
|
return true;
|
|
if (!loplugin::isOkToRemoveArithmeticCast(compiler.getASTContext(), t1, t2,
|
|
cxxFunctionalCastExpr->getSubExpr()))
|
|
{
|
|
return true;
|
|
}
|
|
report(DiagnosticsEngine::Warning, "redundant functional cast from %0 to %1",
|
|
cxxFunctionalCastExpr->getExprLoc())
|
|
<< t2 << t1 << cxxFunctionalCastExpr->getSourceRange();
|
|
return true;
|
|
}
|
|
|
|
/* Check for the creation of unnecessary temporaries when calling a method that takes a param by const & */
|
|
bool VisitCallExpr(CallExpr const* callExpr)
|
|
{
|
|
if (ignoreLocation(callExpr))
|
|
return true;
|
|
const FunctionDecl* functionDecl;
|
|
if (isa<CXXMemberCallExpr>(callExpr))
|
|
functionDecl = dyn_cast<CXXMemberCallExpr>(callExpr)->getMethodDecl();
|
|
else
|
|
functionDecl = callExpr->getDirectCallee();
|
|
if (!functionDecl)
|
|
return true;
|
|
|
|
unsigned len = std::min(callExpr->getNumArgs(), functionDecl->getNumParams());
|
|
for (unsigned i = 0; i < len; ++i)
|
|
{
|
|
// check if param is const&
|
|
auto param = functionDecl->getParamDecl(i);
|
|
auto lvalueType = param->getType()->getAs<LValueReferenceType>();
|
|
if (!lvalueType)
|
|
continue;
|
|
if (!lvalueType->getPointeeType().isConstQualified())
|
|
continue;
|
|
auto paramClassOrStructType = lvalueType->getPointeeType()->getAs<RecordType>();
|
|
if (!paramClassOrStructType)
|
|
continue;
|
|
// check for temporary and functional cast in argument expression
|
|
auto arg = callExpr->getArg(i)->IgnoreImpCasts();
|
|
auto materializeTemporaryExpr = dyn_cast<MaterializeTemporaryExpr>(arg);
|
|
if (!materializeTemporaryExpr)
|
|
continue;
|
|
auto functionalCast = dyn_cast<CXXFunctionalCastExpr>(
|
|
materializeTemporaryExpr->GetTemporaryExpr()->IgnoreImpCasts());
|
|
if (!functionalCast)
|
|
continue;
|
|
auto const t1 = functionalCast->getTypeAsWritten();
|
|
auto const t2 = compat::getSubExprAsWritten(functionalCast)->getType();
|
|
if (t1.getCanonicalType().getTypePtr() != t2.getCanonicalType().getTypePtr())
|
|
continue;
|
|
// Check that the underlying expression is of the same class/struct type as the param i.e. that we are not instantiating
|
|
// something useful
|
|
if (t1.getCanonicalType().getTypePtr() != paramClassOrStructType)
|
|
continue;
|
|
|
|
report(DiagnosticsEngine::Warning, "redundant functional cast from %0 to %1",
|
|
arg->getExprLoc())
|
|
<< t2 << t1 << arg->getSourceRange();
|
|
report(DiagnosticsEngine::Note, "in call to method here", param->getLocation())
|
|
<< param->getSourceRange();
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/* Check for the creation of unnecessary temporaries when calling a constructor that takes a param by const & */
|
|
bool VisitCXXConstructExpr(CXXConstructExpr const* callExpr)
|
|
{
|
|
if (ignoreLocation(callExpr))
|
|
return true;
|
|
const CXXConstructorDecl* functionDecl = callExpr->getConstructor();
|
|
|
|
unsigned len = std::min(callExpr->getNumArgs(), functionDecl->getNumParams());
|
|
for (unsigned i = 0; i < len; ++i)
|
|
{
|
|
// check if param is const&
|
|
auto param = functionDecl->getParamDecl(i);
|
|
auto lvalueType = param->getType()->getAs<LValueReferenceType>();
|
|
if (!lvalueType)
|
|
continue;
|
|
if (!lvalueType->getPointeeType().isConstQualified())
|
|
continue;
|
|
auto paramClassOrStructType = lvalueType->getPointeeType()->getAs<RecordType>();
|
|
if (!paramClassOrStructType)
|
|
continue;
|
|
// check for temporary and functional cast in argument expression
|
|
auto arg = callExpr->getArg(i)->IgnoreImplicit();
|
|
auto functionalCast = dyn_cast<CXXFunctionalCastExpr>(arg);
|
|
if (!functionalCast)
|
|
continue;
|
|
auto const t1 = functionalCast->getTypeAsWritten();
|
|
auto const t2 = compat::getSubExprAsWritten(functionalCast)->getType();
|
|
if (t1.getCanonicalType().getTypePtr() != t2.getCanonicalType().getTypePtr())
|
|
continue;
|
|
// Check that the underlying expression is of the same class/struct type as the param i.e. that we are not instantiating
|
|
// something useful
|
|
if (t1.getCanonicalType().getTypePtr() != paramClassOrStructType)
|
|
continue;
|
|
|
|
report(DiagnosticsEngine::Warning, "redundant functional cast from %0 to %1",
|
|
arg->getExprLoc())
|
|
<< t2 << t1 << arg->getSourceRange();
|
|
report(DiagnosticsEngine::Note, "in call to method here", param->getLocation())
|
|
<< param->getSourceRange();
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr const* expr)
|
|
{
|
|
if (ignoreLocation(expr))
|
|
return true;
|
|
// specifying the name for an init-list is necessary sometimes
|
|
if (isa<InitListExpr>(expr->getSubExpr()->IgnoreImplicit()))
|
|
return true;
|
|
if (isa<CXXStdInitializerListExpr>(expr->getSubExpr()->IgnoreImplicit()))
|
|
return true;
|
|
auto const t1 = expr->getTypeAsWritten();
|
|
auto const t2 = compat::getSubExprAsWritten(expr)->getType();
|
|
if (t1.getCanonicalType().getTypePtr() != t2.getCanonicalType().getTypePtr())
|
|
{
|
|
return true;
|
|
}
|
|
// (a) we do a lot of int/sal_Int32 kind of casts which might be platform necessary?
|
|
// (b) we do bool/bool casts in unit tests to avoid one of the other plugins
|
|
// so just ignore this kind of thing for now
|
|
if (const auto* BT = dyn_cast<BuiltinType>(t1->getUnqualifiedDesugaredType()))
|
|
{
|
|
auto k = BT->getKind();
|
|
if (k == BuiltinType::Double || k == BuiltinType::Float
|
|
|| (k >= BuiltinType::Bool && k <= BuiltinType::Int128))
|
|
return true;
|
|
}
|
|
if (const auto* BT = dyn_cast<BuiltinType>(t2->getUnqualifiedDesugaredType()))
|
|
{
|
|
auto k = BT->getKind();
|
|
if (k == BuiltinType::Double || k == BuiltinType::Float
|
|
|| (k >= BuiltinType::Bool && k <= BuiltinType::Int128))
|
|
return true;
|
|
}
|
|
auto tc = loplugin::TypeCheck(t1);
|
|
if (tc.Typedef("sal_Int32").GlobalNamespace())
|
|
return true;
|
|
|
|
report(DiagnosticsEngine::Warning, "redundant functional cast from %0 to %1",
|
|
expr->getExprLoc())
|
|
<< t2 << t1 << expr->getSourceRange();
|
|
//getParentStmt(expr)->dump();
|
|
return true;
|
|
}
|
|
|
|
private:
|
|
void run() override
|
|
{
|
|
if (!compiler.getLangOpts().CPlusPlus)
|
|
return;
|
|
std::string fn = handler.getMainFileName();
|
|
loplugin::normalizeDotDotInFilePath(fn);
|
|
// necessary on some other platforms
|
|
if (fn == SRCDIR "/sal/osl/unx/socket.cxx")
|
|
return;
|
|
// compile-time check of constant
|
|
if (fn == SRCDIR "/bridges/source/jni_uno/jni_bridge.cxx")
|
|
return;
|
|
TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
|
|
}
|
|
FunctionDecl const* m_CurrentFunctionDecl;
|
|
};
|
|
|
|
static loplugin::Plugin::Registration<RedundantFCast> reg("redundantfcast");
|
|
}
|
|
|
|
/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
|