loplugin:unusedfields improve finding callee

which makes absolutely no difference to the results, but anyhow, would
be a shame to waste the work

Change-Id: I4576528f30986a5ce522c76fdf21873f0ce23f0a
This commit is contained in:
Noel Grandin 2017-09-29 09:05:54 +02:00
parent 2149bbfd27
commit 26c82bd286

View File

@ -83,15 +83,49 @@ public:
};
class CalleeWrapper
{
const FunctionDecl * m_calleeFunctionDecl;
const CXXConstructorDecl * m_cxxConstructorDecl;
const FunctionDecl * m_calleeFunctionDecl = nullptr;
const CXXConstructorDecl * m_cxxConstructorDecl = nullptr;
const FunctionProtoType * m_functionPrototype = nullptr;
public:
CalleeWrapper(const FunctionDecl * calleeFunctionDecl) : m_calleeFunctionDecl(calleeFunctionDecl), m_cxxConstructorDecl(nullptr) {}
CalleeWrapper(const CXXConstructExpr * cxxConstructExpr) : m_calleeFunctionDecl(nullptr), m_cxxConstructorDecl(cxxConstructExpr->getConstructor()) {}
unsigned getNumParams () const
{ return m_calleeFunctionDecl ? m_calleeFunctionDecl->getNumParams() : m_cxxConstructorDecl->getNumParams(); }
const ParmVarDecl * getParamDecl (unsigned i) const
{ return m_calleeFunctionDecl ? m_calleeFunctionDecl->getParamDecl(i) : m_cxxConstructorDecl->getParamDecl(i); }
explicit CalleeWrapper(const FunctionDecl * calleeFunctionDecl) : m_calleeFunctionDecl(calleeFunctionDecl) {}
explicit CalleeWrapper(const CXXConstructExpr * cxxConstructExpr) : m_cxxConstructorDecl(cxxConstructExpr->getConstructor()) {}
explicit CalleeWrapper(const FunctionProtoType * functionPrototype) : m_functionPrototype(functionPrototype) {}
unsigned getNumParams() const
{
if (m_calleeFunctionDecl)
return m_calleeFunctionDecl->getNumParams();
else if (m_cxxConstructorDecl)
return m_cxxConstructorDecl->getNumParams();
else if (m_functionPrototype->param_type_begin() == m_functionPrototype->param_type_end())
// FunctionProtoType will assert if we call getParamTypes() and it has no params
return 0;
else
return m_functionPrototype->getParamTypes().size();
}
const QualType getParamType(unsigned i) const
{
if (m_calleeFunctionDecl)
return m_calleeFunctionDecl->getParamDecl(i)->getType();
else if (m_cxxConstructorDecl)
return m_cxxConstructorDecl->getParamDecl(i)->getType();
else
return m_functionPrototype->getParamTypes()[i];
}
std::string getNameAsString() const
{
if (m_calleeFunctionDecl)
return m_calleeFunctionDecl->getNameAsString();
else if (m_cxxConstructorDecl)
return m_cxxConstructorDecl->getNameAsString();
else
return "";
}
CXXMethodDecl const * getAsCXXMethodDecl() const
{
if (m_calleeFunctionDecl)
return dyn_cast<CXXMethodDecl>(m_calleeFunctionDecl);
return nullptr;
}
};
class UnusedFields:
@ -122,6 +156,7 @@ private:
bool isSomeKindOfZero(const Expr* arg);
bool IsPassedByNonConst(const FieldDecl* fieldDecl, const Stmt * child, CallerWrapper callExpr,
CalleeWrapper calleeFunctionDecl);
llvm::Optional<CalleeWrapper> getCallee(CallExpr const *);
RecordDecl * insideMoveOrCopyDeclParent;
RecordDecl * insideStreamOutputOperator;
@ -492,12 +527,12 @@ void UnusedFields::checkWriteOnly(const FieldDecl* fieldDecl, const Expr* member
else if (auto callExpr = dyn_cast<CallExpr>(parent))
{
// check for calls to ReadXXX() type methods and the operator>>= methods on Any.
const FunctionDecl * calleeFunctionDecl = callExpr->getDirectCallee();
if (calleeFunctionDecl)
auto callee = getCallee(callExpr);
if (callee)
{
// FIXME perhaps a better solution here would be some kind of SAL_PARAM_WRITEONLY attribute
// which we could scatter around.
std::string name = calleeFunctionDecl->getNameAsString();
std::string name = callee->getNameAsString();
std::transform(name.begin(), name.end(), name.begin(), easytolower);
if (startswith(name, "read"))
// this is a write-only call
@ -657,17 +692,17 @@ void UnusedFields::checkReadOnly(const FieldDecl* fieldDecl, const Expr* memberE
}
else if (auto operatorCallExpr = dyn_cast<CXXOperatorCallExpr>(parent))
{
const FunctionDecl * calleeFunctionDecl = operatorCallExpr->getDirectCallee();
if (calleeFunctionDecl)
auto callee = getCallee(operatorCallExpr);
if (callee)
{
// if calling a non-const operator on the field
auto calleeMethodDecl = dyn_cast<CXXMethodDecl>(calleeFunctionDecl);
auto calleeMethodDecl = callee->getAsCXXMethodDecl();
if (calleeMethodDecl
&& operatorCallExpr->getArg(0) == child && !calleeMethodDecl->isConst())
{
bPotentiallyWrittenTo = true;
}
else if (IsPassedByNonConst(fieldDecl, child, operatorCallExpr, calleeFunctionDecl))
else if (IsPassedByNonConst(fieldDecl, child, operatorCallExpr, *callee))
{
bPotentiallyWrittenTo = true;
}
@ -692,7 +727,7 @@ void UnusedFields::checkReadOnly(const FieldDecl* fieldDecl, const Expr* memberE
bPotentiallyWrittenTo = true;
break;
}
if (IsPassedByNonConst(fieldDecl, child, cxxMemberCallExpr, calleeMethodDecl))
if (IsPassedByNonConst(fieldDecl, child, cxxMemberCallExpr, CalleeWrapper(calleeMethodDecl)))
bPotentiallyWrittenTo = true;
}
else
@ -701,15 +736,15 @@ void UnusedFields::checkReadOnly(const FieldDecl* fieldDecl, const Expr* memberE
}
else if (auto cxxConstructExpr = dyn_cast<CXXConstructExpr>(parent))
{
if (IsPassedByNonConst(fieldDecl, child, cxxConstructExpr, cxxConstructExpr))
if (IsPassedByNonConst(fieldDecl, child, cxxConstructExpr, CalleeWrapper(cxxConstructExpr)))
bPotentiallyWrittenTo = true;
break;
}
else if (auto callExpr = dyn_cast<CallExpr>(parent))
{
const FunctionDecl * calleeFunctionDecl = callExpr->getDirectCallee();
if (calleeFunctionDecl) {
if (IsPassedByNonConst(fieldDecl, child, callExpr, calleeFunctionDecl))
auto callee = getCallee(callExpr);
if (callee) {
if (IsPassedByNonConst(fieldDecl, child, callExpr, *callee))
bPotentiallyWrittenTo = true;
} else
bPotentiallyWrittenTo = true; // conservative, could improve
@ -807,14 +842,14 @@ bool UnusedFields::IsPassedByNonConst(const FieldDecl* fieldDecl, const Stmt * c
{
for (unsigned i = 0; i < len; ++i)
if (callExpr.getArg(i) == child)
if (loplugin::TypeCheck(calleeFunctionDecl.getParamDecl(i)->getType()).Pointer().NonConst())
if (loplugin::TypeCheck(calleeFunctionDecl.getParamType(i)).Pointer().NonConst())
return true;
}
else
{
for (unsigned i = 0; i < len; ++i)
if (callExpr.getArg(i) == child)
if (loplugin::TypeCheck(calleeFunctionDecl.getParamDecl(i)->getType()).LvalueReference().NonConst())
if (loplugin::TypeCheck(calleeFunctionDecl.getParamType(i)).LvalueReference().NonConst())
return true;
}
return false;
@ -920,6 +955,49 @@ void UnusedFields::checkTouchedFromOutside(const FieldDecl* fieldDecl, const Exp
}
}
llvm::Optional<CalleeWrapper> UnusedFields::getCallee(CallExpr const * callExpr)
{
FunctionDecl const * functionDecl = callExpr->getDirectCallee();
if (functionDecl)
return CalleeWrapper(functionDecl);
// Extract the functionprototype from a type
Type const * calleeType = callExpr->getCallee()->getType().getTypePtr();
if (auto pointerType = calleeType->getUnqualifiedDesugaredType()->getAs<PointerType>()) {
if (auto prototype = pointerType->getPointeeType()->getUnqualifiedDesugaredType()->getAs<FunctionProtoType>()) {
return CalleeWrapper(prototype);
}
}
llvm::Optional<CalleeWrapper> ret;
auto callee = callExpr->getCallee()->IgnoreParenImpCasts();
if (isa<CXXDependentScopeMemberExpr>(callee)) // template stuff
return ret;
if (isa<UnresolvedLookupExpr>(callee)) // template stuff
return ret;
if (isa<UnresolvedMemberExpr>(callee)) // template stuff
return ret;
calleeType = calleeType->getUnqualifiedDesugaredType();
if (isa<TemplateSpecializationType>(calleeType)) // template stuff
return ret;
if (auto builtinType = dyn_cast<BuiltinType>(calleeType)) {
if (builtinType->getKind() == BuiltinType::Kind::Dependent) // template stuff
return ret;
if (builtinType->getKind() == BuiltinType::Kind::BoundMember) // template stuff
return ret;
}
if (isa<TemplateTypeParmType>(calleeType)) // template stuff
return ret;
callExpr->dump();
callExpr->getCallee()->getType()->dump();
report(
DiagnosticsEngine::Warning, "can't get callee",
callExpr->getExprLoc())
<< callExpr->getSourceRange();
return ret;
}
loplugin::Plugin::Registration< UnusedFields > X("unusedfields", false);
}