objc-arc: evaluate 'readonly' property with no known
life-time to that of its backing 'ivar's lifetime.
// rdar://10558871
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147956 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaObjCProperty.cpp b/lib/Sema/SemaObjCProperty.cpp
index bbc6d23..52b48cc 100644
--- a/lib/Sema/SemaObjCProperty.cpp
+++ b/lib/Sema/SemaObjCProperty.cpp
@@ -518,6 +518,33 @@
S.Diag(property->getLocation(), diag::note_property_declare);
}
+/// setImpliedPropertyAttributeForReadOnlyProperty -
+/// This routine evaludates life-time attributes for a 'readonly'
+/// property with no known lifetime of its own, using backing
+/// 'ivar's attribute, if any. If no backing 'ivar', property's
+/// life-time is assumed 'strong'.
+static void setImpliedPropertyAttributeForReadOnlyProperty(
+ ObjCPropertyDecl *property, ObjCIvarDecl *ivar) {
+ Qualifiers::ObjCLifetime propertyLifetime =
+ getImpliedARCOwnership(property->getPropertyAttributes(),
+ property->getType());
+ if (propertyLifetime != Qualifiers::OCL_None)
+ return;
+
+ if (!ivar) {
+ // if no backing ivar, make property 'strong'.
+ property->setPropertyAttributes(ObjCPropertyDecl::OBJC_PR_strong);
+ return;
+ }
+ // property assumes owenership of backing ivar.
+ QualType ivarType = ivar->getType();
+ Qualifiers::ObjCLifetime ivarLifetime = ivarType.getObjCLifetime();
+ if (ivarLifetime == Qualifiers::OCL_Strong)
+ property->setPropertyAttributes(ObjCPropertyDecl::OBJC_PR_strong);
+ else if (ivarLifetime == Qualifiers::OCL_Weak)
+ property->setPropertyAttributes(ObjCPropertyDecl::OBJC_PR_weak);
+ return;
+}
/// ActOnPropertyImplDecl - This routine performs semantic checks and
/// builds the AST node for a property implementation declaration; declared
@@ -608,11 +635,21 @@
// @synthesize
if (!PropertyIvar)
PropertyIvar = PropertyId;
+ // Check that this is a previously declared 'ivar' in 'IDecl' interface
+ ObjCInterfaceDecl *ClassDeclared;
+ Ivar = IDecl->lookupInstanceVariable(PropertyIvar, ClassDeclared);
+ QualType PropType = property->getType();
+ QualType PropertyIvarType = PropType.getNonReferenceType();
+
+ if (getLangOptions().ObjCAutoRefCount &&
+ PropertyIvarType->isObjCRetainableType() &&
+ (property->getPropertyAttributesAsWritten() &
+ ObjCPropertyDecl::OBJC_PR_readonly)) {
+ setImpliedPropertyAttributeForReadOnlyProperty(property, Ivar);
+ }
+
ObjCPropertyDecl::PropertyAttributeKind kind
= property->getPropertyAttributes();
- QualType PropType = property->getType();
-
- QualType PropertyIvarType = PropType.getNonReferenceType();
// Add GC __weak to the ivar type if the property is weak.
if ((kind & ObjCPropertyDecl::OBJC_PR_weak) &&
@@ -627,9 +664,6 @@
}
}
- // Check that this is a previously declared 'ivar' in 'IDecl' interface
- ObjCInterfaceDecl *ClassDeclared;
- Ivar = IDecl->lookupInstanceVariable(PropertyIvar, ClassDeclared);
if (!Ivar) {
// In ARC, give the ivar a lifetime qualifier based on the
// property attributes.
@@ -1681,6 +1715,21 @@
ObjCPropertyDecl *PropertyDecl = cast<ObjCPropertyDecl>(PDecl);
QualType PropertyTy = PropertyDecl->getType();
+ if (getLangOptions().ObjCAutoRefCount &&
+ (Attributes & ObjCDeclSpec::DQ_PR_readonly) &&
+ PropertyTy->isObjCRetainableType()) {
+ // 'readonly' property with no obvious lifetime.
+ // its life time will be determined by its backing ivar.
+ unsigned rel = (ObjCDeclSpec::DQ_PR_unsafe_unretained |
+ ObjCDeclSpec::DQ_PR_copy |
+ ObjCDeclSpec::DQ_PR_retain |
+ ObjCDeclSpec::DQ_PR_strong |
+ ObjCDeclSpec::DQ_PR_weak |
+ ObjCDeclSpec::DQ_PR_assign);
+ if ((Attributes & rel) == 0)
+ return;
+ }
+
// readonly and readwrite/assign/retain/copy conflict.
if ((Attributes & ObjCDeclSpec::DQ_PR_readonly) &&
(Attributes & (ObjCDeclSpec::DQ_PR_readwrite |