Add front-end infrastructure now address space casts are in LLVM IR.

With the introduction of explicit address space casts into LLVM, there's
a need to provide a new cast kind the front-end can create for C/OpenCL/CUDA
and code to produce address space casts from those kinds when appropriate.

Patch by Michele Scandale!

llvm-svn: 197036

1 files changed, 13 insertions, 2 deletions

diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index 789c986bbed..d734e3c927c 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -1299,7 +1299,18 @@ Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
   case CK_AnyPointerToBlockPointerCast:
   case CK_BitCast: {
     Value *Src = Visit(const_cast<Expr*>(E));
-    return Builder.CreateBitCast(Src, ConvertType(DestTy));
+    llvm::Type *SrcTy = Src->getType();
+    llvm::Type *DstTy = ConvertType(DestTy);
+    if (SrcTy->isPtrOrPtrVectorTy() && DstTy->isPtrOrPtrVectorTy() && 
+        SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace()) {
+      llvm::Type *MidTy = CGF.CGM.getDataLayout().getIntPtrType(SrcTy);
+      return Builder.CreateIntToPtr(Builder.CreatePtrToInt(Src, MidTy), DstTy);
+    }
+    return Builder.CreateBitCast(Src, DstTy);
+  }
+  case CK_AddressSpaceConversion: {
+    Value *Src = Visit(const_cast<Expr*>(E));
+    return Builder.CreateAddrSpaceCast(Src, ConvertType(DestTy));
   }
   case CK_AtomicToNonAtomic:
   case CK_NonAtomicToAtomic:
@@ -1360,7 +1371,7 @@ Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
 
     // Make sure the array decay ends up being the right type.  This matters if
     // the array type was of an incomplete type.
-    return CGF.Builder.CreateBitCast(V, ConvertType(CE->getType()));
+    return CGF.Builder.CreatePointerCast(V, ConvertType(CE->getType()));
   }
   case CK_FunctionToPointerDecay:
     return EmitLValue(E).getAddress();