Changeset c19bc90

Timestamp:

May 26, 2020, 4:03:30 PM (4 years ago)

Author:

Andrew Beach <ajbeach@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

ada0246d

Parents:

b2de2e0

Message:

Better error messages in ExpandCasts?.

File:

• src/Virtual/ExpandCasts.cc (modified) (3 diffs)

src/Virtual/ExpandCasts.cc

@@ -10 +10 @@
 // Created On       : Mon Jul 24 13:59:00 2017
 // Last Modified By : Andrew Beach
-// Last Modified On : Tus Aug  2 14:59:00 2017
-// Update Count     : 1
+// Last Modified On : Tue May 26 14:37:00 2020
+// Update Count     : 2
 //
 
@@ -111 +111 @@
         }
 
+        // Better error locations for generated casts.
+        static CodeLocation castLocation( VirtualCastExpr * castExpr ) {
+                if ( castExpr->location.isSet() ) {
+                        return castExpr->location;
+                } else if ( castExpr->arg->location.isSet() ) {
+                        return castExpr->arg->location;
+                } else if ( castExpr->result->location.isSet() ) {
+                        return castExpr->result->location;
+                } else {
+                        return CodeLocation();
+                }
+        }
+
         Expression * VirtualCastCore::postmutate( VirtualCastExpr * castExpr ) {
                 assertf( castExpr->get_result(), "Virtual Cast target not found before expansion." );
@@ -117 +130 @@
                 assert( pvt_decl );
 
-                // May only cast to a pointer or reference type.
-                // A earlier validation should give a syntax error, this is
-                // just to make sure errors don't creep during translation.
-                // Move to helper with more detailed error messages.
-                PointerType * target_type =
-                        dynamic_cast<PointerType *>( castExpr->get_result() );
-                assert( target_type );
+                // Get the base type of the pointer/reference.
+                Type * base;
+                Type * result_type = castExpr->result;
+                if ( PointerType * target = dynamic_cast<PointerType *>( result_type ) ) {
+                        base = target->base;
+                } else if ( ReferenceType * target = dynamic_cast<ReferenceType *>( result_type ) ) {
+                        base = target->base;
+                } else {
+                        SemanticError( castLocation( castExpr ),
+                                "Virtual cast type must be a pointer or reference type." );
+                }
 
-                StructInstType * target_struct =
-                        dynamic_cast<StructInstType *>( target_type->get_base() );
-                assert( target_struct );
-
+                StructInstType * target_struct = dynamic_cast<StructInstType *>( base );
+                if ( nullptr == target_struct ) {
+                        SemanticError( castLocation( castExpr ),
+                                "Virtual cast type must refer to a structure type." );
+                }
                 StructDecl * target_decl = target_struct->get_baseStruct();
 
                 std::map<std::string, ObjectDecl *>::iterator found =
-                        vtable_instances.find(
-                                get_vtable_inst_name( target_decl->get_name() ) );
+                        vtable_instances.find( get_vtable_inst_name( target_decl->get_name() ) );
                 if ( vtable_instances.end() == found ) {
-                        assertf( false, "virtual table instance not found." );
+                        SemanticError( castLocation( castExpr ),
+                                "Virtual cast type does not have a virtual table instance." );
                 }
                 ObjectDecl * table = found->second;
 
                 Expression * result = new CastExpr(
-                        //new ApplicationExpr(
-                                //new AddressExpr( new VariableExpr( vcast_decl ) ),
-                                //new CastExpr( new VariableExpr( vcast_decl ),
-                                //      new PointerType( noQualifiers,
-                                //              vcast_decl->get_type()->clone()
-                                //              )
-                                //      ),
                         new ApplicationExpr( VariableExpr::functionPointer( vcast_decl ), {
                                         new CastExpr(