[OpenCL] Fix address space for const method call from nonconst (PR43145)

Patch by Anastasia Stulova and Sven van Haastregt.

Differential Revision: https://reviews.llvm.org/D68781

Author: svenvh

clang/lib/Sema/SemaOverload.cpp

@@ -5370,7 +5370,10 @@ Sema::PerformObjectArgumentInitialization(Expr *From,
 
   if (!Context.hasSameType(From->getType(), DestType)) {
     CastKind CK;
-    if (FromRecordType.getAddressSpace() != DestType.getAddressSpace())
+    QualType PteeTy = DestType->getPointeeType();
+    LangAS DestAS =
+        PteeTy.isNull() ? DestType.getAddressSpace() : PteeTy.getAddressSpace();
+    if (FromRecordType.getAddressSpace() != DestAS)
       CK = CK_AddressSpaceConversion;
     else
       CK = CK_NoOp;

clang/test/CodeGenOpenCLCXX/addrspace-of-this.cl

@@ -203,3 +203,14 @@ TEST(__private)
 // IMPL: [[C2GENVOID:%[0-9]+]] = bitcast %class.C addrspace(4)* [[C2GEN]] to i8 addrspace(4)*
 // IMPL: [[C1GENVOID:%[0-9]+]] = bitcast %class.C addrspace(4)* [[C1GEN]] to i8 addrspace(4)*
 // IMPL:  call void @llvm.memcpy.p4i8.p4i8.i32(i8 addrspace(4)* {{.*}}[[C2GENVOID]], i8 addrspace(4)* {{.*}}[[C1GENVOID]]
+
+// Test that calling a const method from a non-const method does not crash Clang.
+class ConstAndNonConstMethod {
+public:
+  void DoConst() const {
+  }
+
+  void DoNonConst() {
+    DoConst();
+  }
+};