In ARC, reclaim all return values of retainable type, not just those

where we have an immediate need of a retained value.

As an exception, don't do this when the call is made as the immediate
operand of a __bridge retain.  This is more in the way of a workaround
than an actual guarantee, so it's acceptable to be brittle here.

rdar://problem/9504800



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@134605 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 16 insertions, 0 deletions

diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index 3002e305ac..5d8789fdda 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -1102,6 +1102,8 @@ const char *CastExpr::getCastKindName() const {
     return "ObjCConsumeObject";
   case CK_ObjCProduceObject:
     return "ObjCProduceObject";
+  case CK_ObjCReclaimReturnedObject:
+    return "ObjCReclaimReturnedObject";
   }
 
   llvm_unreachable("Unhandled cast kind!");
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
index cc8c50198c..9943222b1d 100644
--- a/lib/AST/ExprConstant.cpp
+++ b/lib/AST/ExprConstant.cpp
@@ -1819,6 +1819,7 @@ bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
   case CK_UserDefinedConversion:
   case CK_ObjCProduceObject:
   case CK_ObjCConsumeObject:
+  case CK_ObjCReclaimReturnedObject:
     return false;
 
   case CK_LValueToRValue:
@@ -2325,6 +2326,7 @@ bool ComplexExprEvaluator::VisitCastExpr(const CastExpr *E) {
   case CK_IntegralComplexToBoolean:
   case CK_ObjCProduceObject:
   case CK_ObjCConsumeObject:
+  case CK_ObjCReclaimReturnedObject:
     llvm_unreachable("invalid cast kind for complex value");
 
   case CK_LValueToRValue:
diff --git a/lib/AST/Stmt.cpp b/lib/AST/Stmt.cpp
index e293f324ab..fd6f21d43b 100644
--- a/lib/AST/Stmt.cpp
+++ b/lib/AST/Stmt.cpp
@@ -85,6 +85,18 @@ bool Stmt::CollectingStats(bool Enable) {
   return StatSwitch;
 }
 
+Stmt *Stmt::IgnoreImplicit() {
+  Stmt *s = this;
+
+  if (ExprWithCleanups *ewc = dyn_cast<ExprWithCleanups>(s))
+    s = ewc->getSubExpr();
+
+  while (ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(s))
+    s = ice->getSubExpr();
+
+  return s;
+}
+
 namespace {
   struct good {};
   struct bad {};