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

[svenvh]

Fix formatting, reduce use of auto, and add a test.

[Anastasia]

LGTM! Thanks

clang/lib/Sema/SemaOverload.cpp

ExprResult FromRes =
       PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method);
     if (FromRes.isInvalid())
       return ExprError();
     From = FromRes.get();
   }
 
   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;
     From = ImpCastExprToType(From, DestType, CK, From->getValueKind()).get();
   }
   return From;
 }
 

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

 
 // Test the address space of 'this' when invoking a copy-assignment.
 // COMMON: [[C1GEN:%[.a-z0-9]+]] = addrspacecast %class.C* %c1 to %class.C addrspace(4)*
 // COMMON: [[C2GEN:%[.a-z0-9]+]] = addrspacecast %class.C* %c2 to %class.C addrspace(4)*
 // EXPL: call spir_func dereferenceable(4) %class.C addrspace(4)* @_ZNU3AS41CaSERU3AS4KS_(%class.C addrspace(4)* [[C2GEN]], %class.C addrspace(4)* dereferenceable(4) [[C1GEN]])
 // 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();
+  }
+};