Use specialized param visit function for params

This commit introduce a new public function to visit function parameters
in the default visitor. It allows visitors derived from DefaultVisitor
to override only a small part of the default visitor.

gcc/rust/ChangeLog:

	* ast/rust-ast-visitor.cc (DefaultASTVisitor::visit_function_params):
	Add specialized function to visit function parameters.
	(DefaultASTVisitor::visit): Remove parameter visit and call specialized
	function instead.
	* ast/rust-ast-visitor.h: Add function prototye.
	* resolve/rust-late-name-resolver-2.0.cc (Late::visit): Remove
	function.
	(Late::visit_function_params): Override specialized visit function.
	* resolve/rust-late-name-resolver-2.0.h: Add overriden function
	prototype.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Author: P-E-P

gcc/rust/ast/rust-ast-visitor.cc

@@ -831,6 +831,13 @@ DefaultASTVisitor::visit (AST::UseDeclaration &use_decl)
   visit (use_decl.get_tree ());
 }
 
+void
+DefaultASTVisitor::visit_function_params (AST::Function &function)
+{
+  for (auto &param : function.get_function_params ())
+    visit (param);
+}
+
 void
 DefaultASTVisitor::visit (AST::Function &function)
 {
@@ -839,8 +846,9 @@ DefaultASTVisitor::visit (AST::Function &function)
   visit (function.get_qualifiers ());
   for (auto &generic : function.get_generic_params ())
     visit (generic);
-  for (auto &param : function.get_function_params ())
-    visit (param);
+
+  visit_function_params (function);
+
   if (function.has_return_type ())
     visit (function.get_return_type ());
   if (function.has_where_clause ())

gcc/rust/ast/rust-ast-visitor.h

@@ -242,6 +242,8 @@ class ASTVisitor
 class DefaultASTVisitor : public ASTVisitor
 {
 public:
+  virtual void visit_function_params (AST::Function &function);
+
   virtual void visit (AST::Crate &crate);
 
   virtual void visit (AST::Token &tok) override;

gcc/rust/resolve/rust-late-name-resolver-2.0.cc

@@ -266,34 +266,14 @@ Late::visit (AST::AltPattern &pattern)
 }
 
 void
-Late::visit (AST::Function &function)
+Late::visit_function_params (AST::Function &function)
 {
-  auto def_fn = [this, &function] () {
-    visit_outer_attrs (function);
-    visit (function.get_visibility ());
-    visit (function.get_qualifiers ());
-    for (auto &generic : function.get_generic_params ())
-      visit (generic);
-
-    // We only care about params
-    ctx.bindings.enter (BindingSource::Param);
-
-    for (auto &param : function.get_function_params ())
-      visit (param);
-
-    ctx.bindings.exit ();
-
-    // Back to regular visit
+  ctx.bindings.enter (BindingSource::Param);
 
-    if (function.has_return_type ())
-      visit (function.get_return_type ());
-    if (function.has_where_clause ())
-      visit (function.get_where_clause ());
-    if (function.has_body ())
-      visit (*function.get_definition ());
-  };
+  for (auto &param : function.get_function_params ())
+    visit (param);
 
-  ctx.scoped (Rib::Kind::Function, function.get_node_id (), def_fn);
+  ctx.bindings.exit ();
 }
 
 void

gcc/rust/resolve/rust-late-name-resolver-2.0.h

@@ -37,14 +37,16 @@ class Late : public DefaultResolver
 
   void new_label (Identifier name, NodeId id);
 
+  // Specialized visit bits
+  void visit_function_params (AST::Function &function) override;
+
   // some more label declarations
   void visit (AST::LetStmt &) override;
   // TODO: Do we need this?
   // void visit (AST::Method &) override;
   void visit (AST::IdentifierPattern &) override;
   void visit (AST::StructPatternFieldIdent &) override;
   void visit (AST::AltPattern &) override;
-  void visit (AST::Function &) override;
   void visit (AST::SelfParam &) override;
   void visit (AST::MatchArm &) override;
   void visit (AST::ForLoopExpr &) override;