Add TypeEntry, base class for type section entries (#1349)

The type section currently only has one form: functions. With the GC
proposal, at least two more forms are added: struct and array. To
facilitate this:

* Rename FuncTypeModuleField -> TypeModuleField
* Rename Module::func_types -> Module::types
* Rename func_type_bindings -> type_bindings
* TypeEntry is added as a base class of FuncType
* TypeModuleField stores a unique_ptr to a TypeEntry

1 files changed, 6 insertions, 5 deletions

diff --git a/src/wast-parser.cc b/src/wast-parser.cc
index 42286e08..3468e008 100644
--- a/src/wast-parser.cc
+++ b/src/wast-parser.cc
@@ -260,8 +260,8 @@ void ResolveImplicitlyDefinedFunctionType(const Location& loc,
   if (!decl.has_func_type) {
     Index func_type_index = module->GetFuncTypeIndex(decl.sig);
     if (func_type_index == kInvalidIndex) {
-      auto func_type_field = MakeUnique<FuncTypeModuleField>(loc);
-      func_type_field->func_type.sig = decl.sig;
+      auto func_type_field = MakeUnique<TypeModuleField>(loc);
+      cast<FuncType>(func_type_field->type.get())->sig = decl.sig;
       module->AppendField(std::move(func_type_field));
     }
   }
@@ -1182,13 +1182,14 @@ Result WastParser::ParseFuncModuleField(Module* module) {
 Result WastParser::ParseTypeModuleField(Module* module) {
   WABT_TRACE(ParseTypeModuleField);
   EXPECT(Lpar);
-  auto field = MakeUnique<FuncTypeModuleField>(GetLocation());
+  auto field = MakeUnique<TypeModuleField>(GetLocation());
+  FuncType& func_type = *cast<FuncType>(field->type.get());
   EXPECT(Type);
-  ParseBindVarOpt(&field->func_type.name);
+  ParseBindVarOpt(&func_type.name);
   EXPECT(Lpar);
   EXPECT(Func);
   BindingHash bindings;
-  CHECK_RESULT(ParseFuncSignature(&field->func_type.sig, &bindings));
+  CHECK_RESULT(ParseFuncSignature(&func_type.sig, &bindings));
   CHECK_RESULT(ErrorIfLpar({"param", "result"}));
   EXPECT(Rpar);
   EXPECT(Rpar);