[gcc r14-7455] gccrs: expand: Add stub function for attribute expansion

[Arthur Cohen]

https://gcc.gnu.org/g:b0ab106df5fb26f9fbc971c3034a6391d2292ce0

commit r14-7455-gb0ab106df5fb26f9fbc971c3034a6391d2292ce0
Author: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
Date:   Thu Mar 30 20:40:07 2023 +0200

    gccrs: expand: Add stub function for attribute expansion
    
    Add a stub function and utility functions that should be called on some
    nodes to expand attribute procedural macros.
    
    gcc/rust/ChangeLog:
    
            * expand/rust-expand-visitor.cc (ExpandVisitor::expand_outer_attribute):
            Stub for a single attribute expansion.
            (ExpandVisitor::visit_outer_attrs): Visit the attributes to
            expand on a given item.
            * expand/rust-expand-visitor.h: Add function prototypes.
    
    Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Diff:
---
 gcc/rust/expand/rust-expand-visitor.cc | 27 +++++++++++++++++++++++++++
 gcc/rust/expand/rust-expand-visitor.h  |  8 ++++++++
 2 files changed, 35 insertions(+)

diff --git a/gcc/rust/expand/rust-expand-visitor.cc b/gcc/rust/expand/rust-expand-visitor.cc
index b2d1cf3e0c3..f93accdeb40 100644
--- a/gcc/rust/expand/rust-expand-visitor.cc
+++ b/gcc/rust/expand/rust-expand-visitor.cc
@@ -1349,6 +1349,33 @@ ExpandVisitor::visit (AST::BareFunctionType &type)
     visit (type.get_return_type ());
 }
 
+template <typename T>
+void
+ExpandVisitor::expand_outer_attribute (T &item, AST::SimplePath &path)
+{
+  // FIXME: Implement outer attribute expansion
+}
+
+template <typename T>
+void
+ExpandVisitor::visit_outer_attrs (T &item, std::vector<AST::Attribute> &attrs)
+{
+  for (auto it = attrs.begin (); it != attrs.end (); /* erase => No increment*/)
+    {
+      auto current = *it;
+
+      it = attrs.erase (it);
+      expand_outer_attribute (item, current.get_path ());
+    }
+}
+
+template <typename T>
+void
+ExpandVisitor::visit_outer_attrs (T &item)
+{
+  visit_outer_attrs (item, item.get_outer_attrs ());
+}
+
 template <typename T>
 void
 ExpandVisitor::expand_inner_attribute (T &item, AST::SimplePath &path)
diff --git a/gcc/rust/expand/rust-expand-visitor.h b/gcc/rust/expand/rust-expand-visitor.h
index 66dc1870628..e0ff37cf175 100644
--- a/gcc/rust/expand/rust-expand-visitor.h
+++ b/gcc/rust/expand/rust-expand-visitor.h
@@ -313,6 +313,14 @@ public:
   void visit (AST::InferredType &) override;
   void visit (AST::BareFunctionType &type) override;
 
+  template <typename T>
+  void expand_outer_attribute (T &item, AST::SimplePath &path);
+
+  template <typename T>
+  void visit_outer_attrs (T &item, std::vector<AST::Attribute> &attrs);
+
+  template <typename T> void visit_outer_attrs (T &item);
+
   template <typename T>
   void expand_inner_attribute (T &item, AST::SimplePath &Path);