================
@@ -371,29 +366,38 @@ void FactsGenerator::handleAssignment(const Expr *LHSExpr,
// assigned.
RHSList = getRValueOrigins(RHSExpr, RHSList);
- if (const auto *DRE_LHS = dyn_cast<DeclRefExpr>(LHSExpr))
- markUseAsWrite(DRE_LHS);
+ if (const auto *DRE_LHS = dyn_cast<DeclRefExpr>(LHSExpr)) {
+ QualType QT = DRE_LHS->getDecl()->getType();
+ if (QT->isReferenceType() && hasOrigins(QT->getPointeeType())) {
+ // Writing through a reference uses the binding but overwrites the
+ // pointee. Model this as a Read of the outer origin (keeping the binding
+ // live) and a Write of the inner origins (killing the pointee's
+ // liveness).
+ if (UseFact *UF = UseFacts.lookup(DRE_LHS)) {
+ const OriginList *FullList = UF->getUsedOrigins();
+ assert(FullList);
+ UF->setUsedOrigins(FactMgr.getOriginMgr().createSingleOriginList(
+ FullList->getOuterOriginID()));
+ if (const OriginList *InnerList = FullList->peelOuterOrigin()) {
+ UseFact *WriteUF = FactMgr.createFact<UseFact>(DRE_LHS, InnerList);
+ WriteUF->markAsWritten();
+ CurrentBlockFacts.push_back(WriteUF);
+ }
+ }
+ } else if (!QT->isReferenceType()) {
+ markUseAsWrite(DRE_LHS);
+ }
----------------
Xazax-hun wrote:
Could we avoid repeating `QT->isReferenceType()`? Something like:
```suggestion
if (QT->isReferenceType()) {
if (hasOrigins(QT->getPointeeType()) {
// Writing through a reference uses the binding but overwrites the
// pointee. Model this as a Read of the outer origin (keeping the
binding
// live) and a Write of the inner origins (killing the pointee's
// liveness).
if (UseFact *UF = UseFacts.lookup(DRE_LHS)) {
const OriginList *FullList = UF->getUsedOrigins();
assert(FullList);
UF->setUsedOrigins(FactMgr.getOriginMgr().createSingleOriginList(
FullList->getOuterOriginID()));
if (const OriginList *InnerList = FullList->peelOuterOrigin()) {
UseFact *WriteUF = FactMgr.createFact<UseFact>(DRE_LHS, InnerList);
WriteUF->markAsWritten();
CurrentBlockFacts.push_back(WriteUF);
}
}
}
} else
markUseAsWrite(DRE_LHS);
```
https://github.com/llvm/llvm-project/pull/184295
_______________________________________________
cfe-commits mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
