nac3core: get exception ID from symbol resolver

We need to store the exception class somewhere in order to create them
back in the host. Fixes #200

nac3artiq/src/lib.rs

@@ -87,6 +87,7 @@ struct Nac3 {
     working_directory: TempDir,
     top_levels: Vec<TopLevelComponent>,
     string_store: Arc<RwLock<HashMap<String, i32>>>,
+    exception_ids: Arc<RwLock<HashMap<usize, usize>>>,
 }
 
 create_exception!(nac3artiq, CompileError, exceptions::PyException);
@@ -395,6 +396,7 @@ impl Nac3 {
             pyid_to_def: Default::default(),
             working_directory,
             string_store: Default::default(),
+            exception_ids: Default::default(),
         })
     }
 
@@ -442,6 +444,8 @@ impl Nac3 {
         let builtins = PyModule::import(py, "builtins")?;
         let typings = PyModule::import(py, "typing")?;
         let id_fn = builtins.getattr("id")?;
+        let issubclass = builtins.getattr("issubclass")?;
+        let exn_class = builtins.getattr("Exception")?;
         let store_obj = embedding_map.getattr("store_object").unwrap().to_object(py);
         let store_str = embedding_map.getattr("store_str").unwrap().to_object(py);
         let store_fun = embedding_map.getattr("store_function").unwrap().to_object(py);
@@ -451,7 +455,7 @@ impl Nac3 {
             type_fn: builtins.getattr("type").unwrap().to_object(py),
             origin_ty_fn: typings.getattr("get_origin").unwrap().to_object(py),
             args_ty_fn: typings.getattr("get_args").unwrap().to_object(py),
-            store_obj,
+            store_obj: store_obj.clone(),
             store_str,
         };
         let mut module_to_resolver_cache: HashMap<u64, _> = HashMap::new();
@@ -463,6 +467,18 @@ impl Nac3 {
             let py_module: &PyAny = module.extract(py)?;
             let module_id: u64 = id_fn.call1((py_module,))?.extract()?;
             let helper = helper.clone();
+            let class_obj;
+            if let StmtKind::ClassDef { name, .. } = &stmt.node {
+                let class = py_module.getattr(name.to_string()).unwrap();
+                if issubclass.call1((class, exn_class)).unwrap().extract().unwrap() &&
+                    class.getattr("artiq_builtin").is_err() {
+                    class_obj = Some(class);
+                } else {
+                    class_obj = None;
+                }
+            } else {
+                class_obj = None;
+            }
             let (name_to_pyid, resolver) =
                 module_to_resolver_cache.get(&module_id).cloned().unwrap_or_else(|| {
                     let mut name_to_pyid: HashMap<StrRef, u64> = HashMap::new();
@@ -488,6 +504,7 @@ impl Nac3 {
                         field_to_val: Default::default(),
                         helper,
                         string_store: self.string_store.clone(),
+                        exception_ids: self.exception_ids.clone(),
                     })))
                         as Arc<dyn SymbolResolver + Send + Sync>;
                     let name_to_pyid = Rc::new(name_to_pyid);
@@ -504,6 +521,9 @@ impl Nac3 {
                         e
                     ))
                 })?;
+            if let Some(class_obj) = class_obj {
+                self.exception_ids.write().insert(def_id.0, store_obj.call1(py, (class_obj, ))?.extract(py)?);
+            }
 
             match &stmt.node {
                 StmtKind::FunctionDef { decorator_list, .. } => {
@@ -569,6 +589,7 @@ impl Nac3 {
             module: module.to_object(py),
             helper,
             string_store: self.string_store.clone(),
+            exception_ids: self.exception_ids.clone(),
         }))) as Arc<dyn SymbolResolver + Send + Sync>;
         let (_, def_id, _) = composer
             .register_top_level(synthesized.pop().unwrap(), Some(resolver.clone()), "".into())

nac3artiq/src/symbol_resolver.rs

@@ -41,6 +41,7 @@ pub struct InnerResolver {
     pub primitive_ids: PrimitivePythonId,
     pub helper: PythonHelper,
     pub string_store: Arc<RwLock<HashMap<String, i32>>>,
+    pub exception_ids: Arc<RwLock<HashMap<usize, usize>>>,
     // module specific
     pub name_to_pyid: HashMap<StrRef, u64>,
     pub module: PyObject,
@@ -977,4 +978,9 @@ impl SymbolResolver for Resolver {
             id
         }
     }
+
+    fn get_exception_id(&self, tyid: usize) -> usize {
+        let exn_ids = self.0.exception_ids.read();
+        exn_ids.get(&tyid).cloned().unwrap_or(0)
+    }
 }

nac3core/src/codegen/stmt.rs

@@ -468,7 +468,7 @@ pub fn exn_constructor<'ctx, 'a>(
     let def = defs[zelf_id].read();
     let zelf_name =
         if let TopLevelDef::Class { name, .. } = &*def { *name } else { unreachable!() };
-    let exception_name = format!("0:{}", zelf_name);
+    let exception_name = format!("{}:{}", ctx.resolver.get_exception_id(zelf_id), zelf_name);
     unsafe {
         let id_ptr = ctx.builder.build_in_bounds_gep(zelf, &[zero, zero], "exn.id");
         let id = ctx.resolver.get_string_id(&exception_name);
@@ -641,7 +641,13 @@ pub fn gen_try<'ctx, 'a, G: CodeGenerator>(
                     &mut ctx.unifier,
                     type_.custom.unwrap(),
                 );
-                let exn_id = ctx.resolver.get_string_id(&format!("0:{}", exn_name));
+                let obj_id = if let TypeEnum::TObj { obj_id, .. } = &*ctx.unifier.get_ty(type_.custom.unwrap()) {
+                    *obj_id
+                } else {
+                    unreachable!()
+                };
+                let exception_name = format!("{}:{}", ctx.resolver.get_exception_id(obj_id.0), exn_name);
+                let exn_id = ctx.resolver.get_string_id(&exception_name);
                 let exn_id_global =
                     ctx.module.add_global(ctx.ctx.i32_type(), None, &format!("exn.{}", exn_id));
                 exn_id_global.set_initializer(&ctx.ctx.i32_type().const_int(exn_id as u64, false));

nac3core/src/symbol_resolver.rs

@@ -136,6 +136,7 @@ pub trait SymbolResolver {
 
     fn get_default_param_value(&self, expr: &nac3parser::ast::Expr) -> Option<SymbolValue>;
     fn get_string_id(&self, s: &str) -> i32;
+    fn get_exception_id(&self, tyid: usize) -> usize;
     // handle function call etc.
 }
 

nac3core/src/toplevel/composer.rs

@@ -1281,6 +1281,7 @@ impl TopLevelComposer {
                         ));
                     }
                 }
+                ast::StmtKind::Assign { .. } => {}, // we don't class attributes
                 ast::StmtKind::Pass { .. } => {}
                 ast::StmtKind::Expr { value: _, .. } => {} // typically a docstring; ignoring all expressions matches CPython behavior
                 _ => {