[PATCH] D53764: [OpenCL] Enable address spaces for references in C++

[Romanov Vlad via Phabricator via cfe-commits]

romanovvlad added inline comments.


================
Comment at: cfe/trunk/lib/CodeGen/CGExpr.cpp:4268
+        DestTy.getAddressSpace(), ConvertType(DestTy));
+    return MakeNaturalAlignPointeeAddrLValue(V, DestTy);
+  }
----------------
Hi,

It seems this code doesn't work correctly(repro at the end). TBAA information is lost here because MakeNaturalAlignPointeeAddrLValue constructs LValue with alignment of poinee type but TBAA info is taken from pointer itself what is strange enough. As a result, for example, memcpy with wrong size is generated for copy constructors. 

Repro:

```
class P {
public:
  P(const P &Rhs) = default;

  long a;
  long b;
};

__kernel void foo(__global P* GPtr) {
  P Val = GPtr[0];
}
```

As a solution the line could be replaced with the following:
```
return MakeAddrLValue(Address(V, LV.getAddress().getAlignment()),
                                       E->getType(), LV.getBaseInfo(),
                                       CGM.getTBAAInfoForSubobject(LV, E->getType()));
```
To take all the information from the original pointer.

What do you think about solution?



Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D53764/new/

https://reviews.llvm.org/D53764