improve unusedfields loplugin

to ignore assignments when doing writeonly analysis

Change-Id: I9eb6f2594003a610582dbc20acb7ccf14ef72c6c
This commit is contained in:
Noel Grandin 2017-06-15 09:49:05 +02:00
parent 416752b9e4
commit 2c83c40b43
2 changed files with 34 additions and 10 deletions

View File

@ -194,8 +194,7 @@ bool ConstParams::checkIfCanBeConst(const Stmt* stmt)
return checkIfCanBeConst(parent);
}
return true;
} else if (isa<BinaryOperator>(parent)) {
const BinaryOperator* binaryOp = dyn_cast<BinaryOperator>(parent);
} else if (auto binaryOp = dyn_cast<BinaryOperator>(parent)) {
BinaryOperator::Opcode op = binaryOp->getOpcode();
// TODO could do better, but would require tracking the LHS
if (binaryOp->getRHS() == stmt && op == BO_Assign) {

View File

@ -271,11 +271,30 @@ bool UnusedFields::VisitMemberExpr( const MemberExpr* memberExpr )
bPotentiallyReadFrom = true;
break;
}
else if (isa<ReturnStmt>(parent) || isa<CXXConstructExpr>(parent)
|| isa<ConditionalOperator>(parent) || isa<SwitchStmt>(parent) || isa<ArraySubscriptExpr>(parent)
|| isa<DeclStmt>(parent) || isa<WhileStmt>(parent) || isa<CXXNewExpr>(parent)
|| isa<ForStmt>(parent) || isa<InitListExpr>(parent)
|| isa<BinaryOperator>(parent) || isa<CXXDependentScopeMemberExpr>(parent)
else if (auto binaryOp = dyn_cast<BinaryOperator>(parent))
{
BinaryOperator::Opcode op = binaryOp->getOpcode();
// If the child is on the LHS and it is an assignment, we are obviously not reading from it,
// so walk up the tree.
if (binaryOp->getLHS() == child && op == BO_Assign) {
child = parent;
parent = parentStmt(parent);
} else {
bPotentiallyReadFrom = true;
break;
}
}
else if (isa<ReturnStmt>(parent)
|| isa<CXXConstructExpr>(parent)
|| isa<ConditionalOperator>(parent)
|| isa<SwitchStmt>(parent)
|| isa<ArraySubscriptExpr>(parent)
|| isa<DeclStmt>(parent)
|| isa<WhileStmt>(parent)
|| isa<CXXNewExpr>(parent)
|| isa<ForStmt>(parent)
|| isa<InitListExpr>(parent)
|| isa<CXXDependentScopeMemberExpr>(parent)
|| isa<UnresolvedMemberExpr>(parent)
|| isa<MaterializeTemporaryExpr>(parent)) //???
{
@ -283,9 +302,13 @@ bool UnusedFields::VisitMemberExpr( const MemberExpr* memberExpr )
break;
}
else if (isa<CXXDeleteExpr>(parent)
|| isa<UnaryExprOrTypeTraitExpr>(parent)
|| isa<CXXUnresolvedConstructExpr>(parent) || isa<CompoundStmt>(parent)
|| isa<CXXTypeidExpr>(parent) || isa<DefaultStmt>(parent))
|| isa<UnaryExprOrTypeTraitExpr>(parent)
|| isa<CXXUnresolvedConstructExpr>(parent)
|| isa<CompoundStmt>(parent)
|| isa<LabelStmt>(parent)
|| isa<CXXForRangeStmt>(parent)
|| isa<CXXTypeidExpr>(parent)
|| isa<DefaultStmt>(parent))
{
break;
}
@ -305,7 +328,9 @@ bool UnusedFields::VisitMemberExpr( const MemberExpr* memberExpr )
parent->dump();
}
if (bPotentiallyReadFrom)
{
readFromSet.insert(fieldInfo);
}
return true;
}