[cfe-commits] r167331 - in /cfe/trunk: lib/CodeGen/CGObjCMac.cpp test/CodeGenObjC/mrr-captured-block-var-inlined-layout.m

[John McCall]

On Nov 2, 2012, at 3:51 PM, Fariborz Jahanian wrote:
> Author: fjahanian
> Date: Fri Nov  2 17:51:18 2012
> New Revision: 167331
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=167331&view=rev
> Log:
> objective-C mrr block. Block variable layout metadata in
> mrr mode.
> 
> Added:
>    cfe/trunk/test/CodeGenObjC/mrr-captured-block-var-inlined-layout.m
> Modified:
>    cfe/trunk/lib/CodeGen/CGObjCMac.cpp
> 
> Modified: cfe/trunk/lib/CodeGen/CGObjCMac.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjCMac.cpp?rev=167331&r1=167330&r2=167331&view=diff
> ==============================================================================
> --- cfe/trunk/lib/CodeGen/CGObjCMac.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CGObjCMac.cpp Fri Nov  2 17:51:18 2012
> @@ -942,6 +942,8 @@
>                            unsigned int BytePos, bool ForStrongLayout,
>                            bool &HasUnion);
> 
> +  Qualifiers::ObjCLifetime GetObjCLifeTime(QualType QT);
> +  
>   void UpdateRunSkipBlockVars(bool IsByref,
>                               Qualifiers::ObjCLifetime LifeTime,
>                               unsigned FieldOffset,
> @@ -1962,6 +1964,25 @@
>   return C;
> }
> 
> +Qualifiers::ObjCLifetime CGObjCCommonMac::GetObjCLifeTime(QualType FQT) {

For consistency, please call this getObjCLifetime, or better yet, something
like getBlockCaptureLifetime.  Also, please add a comment explaining its
purpose.

> +  if (CGM.getLangOpts().ObjCAutoRefCount)
> +    return FQT.getObjCLifetime();
> +  
> +  // MRR, is more ad hoc.
> +  if (FQT.isObjCGCStrong())
> +    return Qualifiers::OCL_Strong;
> +  if (FQT.isObjCGCWeak())
> +    return Qualifiers::OCL_Weak;

I don't think these qualifiers can ever be present in an MRC build,
and we should never be emitting this layout in a GC build.

> +  if (FQT->isObjCObjectPointerType() || FQT->isBlockPointerType())
> +    return Qualifiers::OCL_Strong;

This is true of direct captures, but an MRR __block variable of a id/block
actually uses __unsafe_unretained semantics.

> +  if (const PointerType *PT = FQT->getAs<PointerType>())
> +    return (GetObjCLifeTime(PT->getPointeeType()));

This seems wrong.  There's no difference between an id* and a char*
for the purposes of this layout — it's just opaque data.  An id* is
definitely not a strong capture.

John.