COWptr/variant fixes (WIP)

p4lang · Dec 13, 2024 · 74626b4 · 74626b4
1 parent 70531da
commit 74626b4
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Showing 2 changed files with 20 additions and 6 deletions.
diff --git a/ir/copy_on_write_inl.h b/ir/copy_on_write_inl.h
@@ -233,6 +233,15 @@ struct COWfieldref<T, NameMap<U, MAP>, field> {
 
 // FIXME -- need NodeMap specializations if any backend ever uses that template
 
+/* specialization for std::variant */
+template <class T, class... TYPES, std::variant<TYPES...> T::*field>
+struct COWfieldref<T, std::variant<TYPES...>, field> {
+    COWinfo<T>        *info;
+
+    size_t index() const { return info->get()->*field.index(); }
+    // FIXME -- what do we need here?  Do we need a specialization of std::visit?
+};
+
 }  // namespace P4::IR
 
 #endif /* IR_COPY_ON_WRITE_INL_H_ */
diff --git a/tools/ir-generator/irclass.cpp b/tools/ir-generator/irclass.cpp
@@ -448,12 +448,17 @@ IrElement::access_t IrClass::outputCOWfieldrefs(std::ostream &out) const {
             if (fld->isStatic) continue;
             if (e->access != access) out << indent << (access = e->access);
             out << indent << "COWfieldref<" << name << ", ";
-            const IrClass *cls = fld->type->resolve(fld->clss ? fld->clss->containedIn : nullptr);
-            if (cls != nullptr && !fld->isInline) out << "const ";
-            out << fld->type->toString();
-            if (cls != nullptr && !fld->isInline) out << "*";
-            out << fld->type->declSuffix() << ", &" << name << "::" << fld->name << "> "
-                << fld->name << ";\n";
+            if (fld->is<IrVariantField>()) {
+                out << fld->name << "_variant";
+            } else {
+                const IrClass *cls = fld->type->resolve(fld->clss ? fld->clss->containedIn
+                                                                  : nullptr);
+                if (cls != nullptr && !fld->isInline) out << "const ";
+                out << fld->type->toString();
+                if (cls != nullptr && !fld->isInline) out << "*";
+                out << fld->type->declSuffix();
+            }
+            out << ", &" << name << "::" << fld->name << "> " << fld->name << ";\n";
         }
     }
     return access;