Automatic Reference Counting.

Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.

Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@133103 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 30 insertions, 2 deletions

diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index d349220e3d..01bd0ed336 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -1740,7 +1740,12 @@ ExprResult Parser::ParseBuiltinPrimaryExpression() {
 ///         '(' type-name ')' '{' initializer-list ',' '}'
 ///       cast-expression: [C99 6.5.4]
 ///         '(' type-name ')' cast-expression
-///
+/// [ARC]   bridged-cast-expression
+/// 
+/// [ARC] bridged-cast-expression:
+///         (__bridge type-name) cast-expression
+///         (__bridge_transfer type-name) cast-expression
+///         (__bridge_retained type-name) cast-expression
 ExprResult
 Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr,
                              ParsedType TypeOfCast, ParsedType &CastTy,
@@ -1772,7 +1777,30 @@ Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr,
     // If the substmt parsed correctly, build the AST node.
     if (!Stmt.isInvalid())
       Result = Actions.ActOnStmtExpr(OpenLoc, Stmt.take(), Tok.getLocation());
-
+  } else if (ExprType >= CompoundLiteral && 
+             (Tok.is(tok::kw___bridge) || 
+              Tok.is(tok::kw___bridge_transfer) ||
+              Tok.is(tok::kw___bridge_retained))) {
+    // Parse an Objective-C ARC ownership cast expression.
+    ObjCBridgeCastKind Kind;
+    if (Tok.is(tok::kw___bridge))
+      Kind = OBC_Bridge;
+    else if (Tok.is(tok::kw___bridge_transfer))
+      Kind = OBC_BridgeTransfer;
+    else 
+      Kind = OBC_BridgeRetained;
+             
+    SourceLocation BridgeKeywordLoc = ConsumeToken();
+    TypeResult Ty = ParseTypeName();
+    SourceLocation RParenLoc = MatchRHSPunctuation(tok::r_paren, OpenLoc);
+    ExprResult SubExpr = ParseCastExpression(false, false, ParsedType());
+    
+    if (Ty.isInvalid() || SubExpr.isInvalid())
+      return ExprError();
+    
+    return Actions.ActOnObjCBridgedCast(getCurScope(), OpenLoc, Kind,
+                                        BridgeKeywordLoc, Ty.get(),
+                                        RParenLoc, SubExpr.get());
   } else if (ExprType >= CompoundLiteral &&
              isTypeIdInParens(isAmbiguousTypeId)) {