Generate the objc_read_weak API when calling

a __weak block. Fixes radar 7628591.

llvm-svn: 95822

2 files changed, 45 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGBlocks.cpp b/clang/lib/CodeGen/CGBlocks.cpp
index 05d138b2a2b..46b62441d6e 100644
--- a/clang/lib/CodeGen/CGBlocks.cpp
+++ b/clang/lib/CodeGen/CGBlocks.cpp
@@ -13,6 +13,7 @@
 
 #include "CGDebugInfo.h"
 #include "CodeGenFunction.h"
+#include "CGObjCRuntime.h"
 #include "CodeGenModule.h"
 #include "clang/AST/DeclObjC.h"
 #include "llvm/Module.h"
@@ -355,7 +356,21 @@ llvm::Value *CodeGenFunction::BuildBlockLiteralTmp(const BlockExpr *BE) {
   }
 
   QualType BPT = BE->getType();
-  return Builder.CreateBitCast(V, ConvertType(BPT));
+  V = Builder.CreateBitCast(V, ConvertType(BPT));
+  // See if this is a __weak block variable and the must call objc_read_weak
+  // on it.
+  const FunctionType *ftype = BPT->getPointeeType()->getAs<FunctionType>();
+  QualType RES = ftype->getResultType();
+  if (RES.isObjCGCWeak()) {
+    // Must cast argument to id*
+    const llvm::Type *ObjectPtrTy = 
+      ConvertType(CGM.getContext().getObjCIdType());
+    const llvm::Type *PtrObjectPtrTy = 
+      llvm::PointerType::getUnqual(ObjectPtrTy);
+    V = Builder.CreateBitCast(V, PtrObjectPtrTy);
+    V =  CGM.getObjCRuntime().EmitObjCWeakRead(*this, V);
+  }
+  return V;
 }
 
 
diff --git a/clang/test/CodeGenObjC/objc2-weak-block-call.m b/clang/test/CodeGenObjC/objc2-weak-block-call.m
new file mode 100644
index 00000000000..a3514b0caa0
--- /dev/null
+++ b/clang/test/CodeGenObjC/objc2-weak-block-call.m
@@ -0,0 +1,29 @@
+// RUN: %clang_cc1 -fblocks -fobjc-gc -triple x86_64-apple-darwin -S %s -o %t-64.s
+// RUN: FileCheck -check-prefix LP64 --input-file=%t-64.s %s
+// RUN: %clang_cc1 -fblocks -fobjc-gc -triple i386-apple-darwin -S %s -o %t-32.s
+// RUN: FileCheck -check-prefix LP32 --input-file=%t-32.s %s
+
+@interface MyView
+- (void)MyView_sharedInit;
+@end
+
+void foo(MyView *(^obj)(void)) ;
+
+@implementation MyView
+- (void)MyView_sharedInit {
+    
+    __block __weak MyView *weakSelf = self;
+    foo(
+    ^{
+	return weakSelf;
+    });
+
+}
+@end
+
+// CHECK-LP64: callq    _objc_read_weak
+// CHECK-LP64: callq    _objc_read_weak
+
+// CHECK-LP32: call     L_objc_read_weak
+// CHECK-LP32: call     L_objc_read_weak
+