1 files changed, 113 insertions, 0 deletions
diff --git a/gcc/rust/ast/rust-collect-lang-items.cc b/gcc/rust/ast/rust-collect-lang-items.cc
new file mode 100644
index 0000000..cd6be7f
--- /dev/null
+++ b/gcc/rust/ast/rust-collect-lang-items.cc
@@ -0,0 +1,113 @@
+// Copyright (C) 2024 Free Software Foundation, Inc.
+
+// This file is part of GCC.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with GCC; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include "rust-collect-lang-items.h"
+#include "optional.h"
+#include "rust-ast-collector.h"
+#include "rust-ast-visitor.h"
+#include "rust-ast.h"
+#include "rust-attribute-values.h"
+#include "rust-attributes.h"
+#include "rust-hir-map.h"
+#include "rust-item.h"
+
+namespace Rust {
+namespace AST {
+
+template <typename T>
+tl::optional<LangItem::Kind>
+get_lang_item_attr (const T &maybe_lang_item)
+{
+  for (const auto &attr : maybe_lang_item.get_outer_attrs ())
+    {
+      const auto &str_path = attr.get_path ().as_string ();
+      if (!Analysis::Attributes::is_known (str_path))
+	{
+	  rust_error_at (attr.get_locus (), "unknown attribute %qs",
+			 str_path.c_str ());
+	  continue;
+	}
+
+      bool is_lang_item = str_path == Values::Attributes::LANG
+			  && attr.has_attr_input ()
+			  && attr.get_attr_input ().get_attr_input_type ()
+			       == AST::AttrInput::AttrInputType::LITERAL;
+
+      if (is_lang_item)
+	{
+	  auto &literal
+	    = static_cast<AST::AttrInputLiteral &> (attr.get_attr_input ());
+	  const auto &lang_item_type_str = literal.get_literal ().as_string ();
+
+	  return LangItem::Parse (lang_item_type_str);
+	}
+    }
+
+  return tl::nullopt;
+}
+
+template <typename T>
+void
+CollectLangItems::maybe_add_lang_item (const T &item)
+{
+  if (auto lang_item = get_lang_item_attr (item))
+    mappings.insert_lang_item_node (lang_item.value (), item.get_node_id ());
+}
+
+void
+CollectLangItems::visit (AST::Trait &item)
+{
+  maybe_add_lang_item (item);
+
+  DefaultASTVisitor::visit (item);
+}
+
+void
+CollectLangItems::visit (AST::TraitItemType &item)
+{
+  maybe_add_lang_item (item);
+
+  DefaultASTVisitor::visit (item);
+}
+
+void
+CollectLangItems::visit (AST::Function &item)
+{
+  maybe_add_lang_item (item);
+
+  DefaultASTVisitor::visit (item);
+}
+
+void
+CollectLangItems::visit (AST::StructStruct &item)
+{
+  maybe_add_lang_item (item);
+
+  DefaultASTVisitor::visit (item);
+}
+
+void
+CollectLangItems::visit (AST::EnumItem &item)
+{
+  maybe_add_lang_item (item);
+
+  DefaultASTVisitor::visit (item);
+}
+
+} // namespace AST
+} // namespace Rust