Document the existing objc_precise_lifetime attribute.
Introduce and document a new objc_returns_inner_pointer
attribute, and consume it by performing a retain+autorelease
on message receivers when they're not immediately loaded from
an object with precise lifetime.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@135764 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/AttributeList.cpp b/lib/Sema/AttributeList.cpp
index 5a8330b..2106853 100644
--- a/lib/Sema/AttributeList.cpp
+++ b/lib/Sema/AttributeList.cpp
@@ -163,6 +163,7 @@
.Case("vec_type_hint", IgnoredAttribute)
.Case("objc_exception", AT_objc_exception)
.Case("objc_method_family", AT_objc_method_family)
+ .Case("objc_returns_inner_pointer", AT_objc_returns_inner_pointer)
.Case("ext_vector_type", AT_ext_vector_type)
.Case("neon_vector_type", AT_neon_vector_type)
.Case("neon_polyvector_type", AT_neon_polyvector_type)
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 61b7b3e..ad9b6dd 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -2767,6 +2767,33 @@
};
}
+static void handleObjCReturnsInnerPointerAttr(Sema &S, Decl *D,
+ const AttributeList &attr) {
+ SourceLocation loc = attr.getLoc();
+
+ ObjCMethodDecl *method = dyn_cast<ObjCMethodDecl>(D);
+
+ if (!isa<ObjCMethodDecl>(method)) {
+ S.Diag(method->getLocStart(), diag::err_attribute_wrong_decl_type)
+ << SourceRange(loc, loc) << attr.getName() << 13 /* methods */;
+ return;
+ }
+
+ // Check that the method returns a normal pointer.
+ QualType resultType = method->getResultType();
+ if (!resultType->isPointerType() || resultType->isObjCRetainableType()) {
+ S.Diag(method->getLocStart(), diag::warn_ns_attribute_wrong_return_type)
+ << SourceRange(loc)
+ << attr.getName() << /*method*/ 1 << /*non-retainable pointer*/ 2;
+
+ // Drop the attribute.
+ return;
+ }
+
+ method->addAttr(
+ ::new (S.Context) ObjCReturnsInnerPointerAttr(loc, S.Context));
+}
+
static void handleObjCOwnershipAttr(Sema &S, Decl *D,
const AttributeList &Attr) {
if (hasDeclarator(D)) return;
@@ -2969,6 +2996,9 @@
case AttributeList::AT_objc_precise_lifetime:
handleObjCPreciseLifetimeAttr(S, D, Attr); break;
+ case AttributeList::AT_objc_returns_inner_pointer:
+ handleObjCReturnsInnerPointerAttr(S, D, Attr); break;
+
// Checker-specific.
case AttributeList::AT_cf_consumed:
case AttributeList::AT_ns_consumed: handleNSConsumedAttr (S, D, Attr); break;