[committed 041/103] gccrs: rust: Replace uses of ASTFragment -> Fragment

[arthur.cohen@embecosm.com]

From: Arthur Cohen <arthur.cohen@embecosm.com>

gcc/rust/ChangeLog:

	* ast/rust-ast.h (class ASTFragment): Remove old ASTFragment class.
	* ast/rust-macro.h (class MacroRulesDefinition): Use new Fragment API.
	* expand/rust-attribute-visitor.h: Likewise.
	* expand/rust-macro-builtins.cc (macro_end_token): Likewise.
	(MacroBuiltin::assert): Likewise.
	(MacroBuiltin::file): Likewise.
	(MacroBuiltin::column): Likewise.
	(MacroBuiltin::include_bytes): Likewise.
	(MacroBuiltin::include_str): Likewise.
	(MacroBuiltin::compile_error): Likewise.
	(MacroBuiltin::concat): Likewise.
	(MacroBuiltin::env): Likewise.
	(MacroBuiltin::cfg): Likewise.
	(MacroBuiltin::include): Likewise.
	(MacroBuiltin::line): Likewise.
	* expand/rust-macro-builtins.h: Likewise.
	* expand/rust-macro-expand.cc (MacroExpander::expand_decl_macro): Likewise.
	(MacroExpander::expand_invoc): Likewise.
	(MacroExpander::match_repetition): Likewise.
	(parse_many): Likewise.
	(transcribe_many_items): Likewise.
	(transcribe_many_ext): Likewise.
	(transcribe_many_trait_items): Likewise.
	(transcribe_many_impl_items): Likewise.
	(transcribe_many_trait_impl_items): Likewise.
	(transcribe_expression): Likewise.
	(transcribe_type): Likewise.
	(transcribe_on_delimiter): Likewise.
	(tokens_to_str): Likewise.
	* expand/rust-macro-expand.h (struct MacroExpander): Likewise.
	* util/rust-hir-map.cc (Mappings::insert_macro_def): Likewise.
---
 gcc/rust/ast/rust-ast.h                  | 132 -----------------------
 gcc/rust/ast/rust-macro.h                |  18 ++--
 gcc/rust/expand/rust-attribute-visitor.h |   4 +-
 gcc/rust/expand/rust-macro-builtins.cc   |  72 ++++++-------
 gcc/rust/expand/rust-macro-builtins.h    |  40 ++++---
 gcc/rust/expand/rust-macro-expand.cc     |  42 ++++----
 gcc/rust/expand/rust-macro-expand.h      |  23 ++--
 gcc/rust/util/rust-hir-map.cc            |   4 +-
 8 files changed, 100 insertions(+), 235 deletions(-)

diff --git a/gcc/rust/ast/rust-ast.h b/gcc/rust/ast/rust-ast.h
index ccabccd6aff..3d602b1a379 100644
--- a/gcc/rust/ast/rust-ast.h
+++ b/gcc/rust/ast/rust-ast.h
@@ -1858,138 +1858,6 @@ public:
   }
 };
 
-/* Basically, a "fragment" that can be incorporated into the AST, created as
- * a result of macro expansion. Really annoying to work with due to the fact
- * that macros can really expand to anything. As such, horrible representation
- * at the moment. */
-class ASTFragment
-{
-private:
-  /* basic idea: essentially, a vector of tagged unions of different AST node
-   * types. Now, this could actually be stored without a tagged union if the
-   * different AST node types had a unified parent, but that would create
-   * issues with the diamond problem or significant performance penalties. So
-   * a tagged union had to be used instead. A vector is used to represent the
-   * ability for a macro to expand to two statements, for instance. */
-
-  std::vector<SingleASTNode> nodes;
-  bool fragment_is_error;
-
-  /**
-   * We need to make a special case for Expression and Type fragments as only
-   * one Node will be extracted from the `nodes` vector
-   */
-
-  bool is_single_fragment () const { return nodes.size () == 1; }
-
-  bool is_single_fragment_of_kind (SingleASTNode::NodeType expected) const
-  {
-    return is_single_fragment () && nodes[0].get_kind () == expected;
-  }
-
-  void assert_single_fragment (SingleASTNode::NodeType expected) const
-  {
-    static const std::map<SingleASTNode::NodeType, const char *> str_map = {
-      {SingleASTNode::NodeType::IMPL, "impl"},
-      {SingleASTNode::NodeType::ITEM, "item"},
-      {SingleASTNode::NodeType::TYPE, "type"},
-      {SingleASTNode::NodeType::EXPRESSION, "expr"},
-      {SingleASTNode::NodeType::STMT, "stmt"},
-      {SingleASTNode::NodeType::EXTERN, "extern"},
-      {SingleASTNode::NodeType::TRAIT, "trait"},
-      {SingleASTNode::NodeType::TRAIT_IMPL, "trait impl"},
-    };
-
-    auto actual = nodes[0].get_kind ();
-    auto fail = false;
-
-    if (!is_single_fragment ())
-      {
-	rust_error_at (Location (), "fragment is not single");
-	fail = true;
-      }
-
-    if (actual != expected)
-      {
-	rust_error_at (
-	  Location (),
-	  "invalid fragment operation: expected %qs node, got %qs node",
-	  str_map.find (expected)->second,
-	  str_map.find (nodes[0].get_kind ())->second);
-	fail = true;
-      }
-
-    rust_assert (!fail);
-  }
-
-public:
-  ASTFragment (std::vector<SingleASTNode> nodes, bool fragment_is_error = false)
-    : nodes (std::move (nodes)), fragment_is_error (fragment_is_error)
-  {
-    if (fragment_is_error)
-      rust_assert (nodes.empty ());
-  }
-
-  ASTFragment (ASTFragment const &other)
-    : fragment_is_error (other.fragment_is_error)
-  {
-    nodes.clear ();
-    nodes.reserve (other.nodes.size ());
-    for (auto &n : other.nodes)
-      {
-	nodes.push_back (n);
-      }
-  }
-
-  ASTFragment &operator= (ASTFragment const &other)
-  {
-    fragment_is_error = other.fragment_is_error;
-    nodes.clear ();
-    nodes.reserve (other.nodes.size ());
-    for (auto &n : other.nodes)
-      {
-	nodes.push_back (n);
-      }
-
-    return *this;
-  }
-
-  static ASTFragment create_error () { return ASTFragment ({}, true); }
-
-  std::vector<SingleASTNode> &get_nodes () { return nodes; }
-  bool is_error () const { return fragment_is_error; }
-
-  bool should_expand () const { return !is_error (); }
-
-  bool is_expression_fragment () const
-  {
-    return is_single_fragment_of_kind (SingleASTNode::NodeType::EXPRESSION);
-  }
-
-  bool is_type_fragment () const
-  {
-    return is_single_fragment_of_kind (SingleASTNode::NodeType::TYPE);
-  }
-
-  std::unique_ptr<Expr> take_expression_fragment ()
-  {
-    assert_single_fragment (SingleASTNode::NodeType::EXPRESSION);
-    return nodes[0].take_expr ();
-  }
-
-  std::unique_ptr<Type> take_type_fragment ()
-  {
-    assert_single_fragment (SingleASTNode::NodeType::TYPE);
-    return nodes[0].take_type ();
-  }
-
-  void accept_vis (ASTVisitor &vis)
-  {
-    for (auto &node : nodes)
-      node.accept_vis (vis);
-  }
-};
-
 // A crate AST object - holds all the data for a single compilation unit
 struct Crate
 {
diff --git a/gcc/rust/ast/rust-macro.h b/gcc/rust/ast/rust-macro.h
index 798bc974fbb..fc4b5b82fb5 100644
--- a/gcc/rust/ast/rust-macro.h
+++ b/gcc/rust/ast/rust-macro.h
@@ -21,6 +21,7 @@
 
 #include "rust-system.h"
 #include "rust-ast.h"
+#include "rust-ast-fragment.h"
 #include "rust-location.h"
 
 namespace Rust {
@@ -456,8 +457,7 @@ class MacroRulesDefinition : public MacroItem
   std::vector<MacroRule> rules; // inlined form
   Location locus;
 
-  std::function<ASTFragment (Location, MacroInvocData &)>
-    associated_transcriber;
+  std::function<Fragment (Location, MacroInvocData &)> associated_transcriber;
   // Since we can't compare std::functions, we need to use an extra boolean
   bool is_builtin_rule;
 
@@ -468,10 +468,10 @@ class MacroRulesDefinition : public MacroItem
    * should make use of the actual rules. If the macro is builtin, then another
    * associated transcriber should be used
    */
-  static ASTFragment dummy_builtin (Location, MacroInvocData &)
+  static Fragment dummy_builtin (Location, MacroInvocData &)
   {
     gcc_unreachable ();
-    return ASTFragment::create_error ();
+    return Fragment::create_error ();
   }
 
   /* NOTE: in rustc, macro definitions are considered (and parsed as) a type
@@ -491,9 +491,9 @@ public:
       associated_transcriber (dummy_builtin), is_builtin_rule (false)
   {}
 
-  MacroRulesDefinition (Identifier builtin_name, DelimType delim_type,
-			std::function<ASTFragment (Location, MacroInvocData &)>
-			  associated_transcriber)
+  MacroRulesDefinition (
+    Identifier builtin_name, DelimType delim_type,
+    std::function<Fragment (Location, MacroInvocData &)> associated_transcriber)
     : outer_attrs (std::vector<Attribute> ()), rule_name (builtin_name),
       delim_type (delim_type), rules (std::vector<MacroRule> ()),
       locus (Location ()), associated_transcriber (associated_transcriber),
@@ -521,14 +521,14 @@ public:
   const std::vector<MacroRule> &get_rules () const { return rules; }
 
   bool is_builtin () const { return is_builtin_rule; }
-  const std::function<ASTFragment (Location, MacroInvocData &)> &
+  const std::function<Fragment (Location, MacroInvocData &)> &
   get_builtin_transcriber () const
   {
     rust_assert (is_builtin ());
     return associated_transcriber;
   }
   void set_builtin_transcriber (
-    std::function<ASTFragment (Location, MacroInvocData &)> transcriber)
+    std::function<Fragment (Location, MacroInvocData &)> transcriber)
   {
     associated_transcriber = transcriber;
     is_builtin_rule = true;
diff --git a/gcc/rust/expand/rust-attribute-visitor.h b/gcc/rust/expand/rust-attribute-visitor.h
index 80f9d4b4ded..6b562bd49b1 100644
--- a/gcc/rust/expand/rust-attribute-visitor.h
+++ b/gcc/rust/expand/rust-attribute-visitor.h
@@ -56,11 +56,11 @@ public:
    * @return Either the expanded fragment or an empty errored-out fragment
    * indicating an expansion failure.
    */
-  AST::ASTFragment expand_macro_fragment_recursive ()
+  AST::Fragment expand_macro_fragment_recursive ()
   {
     auto fragment = expander.take_expanded_fragment (*this);
     unsigned int original_depth = expander.expansion_depth;
-    auto final_fragment = AST::ASTFragment ({}, true);
+    auto final_fragment = AST::Fragment ({}, true);
 
     while (fragment.should_expand ())
       {
diff --git a/gcc/rust/expand/rust-macro-builtins.cc b/gcc/rust/expand/rust-macro-builtins.cc
index a230ad9f2d8..2a8a3f752f4 100644
--- a/gcc/rust/expand/rust-macro-builtins.cc
+++ b/gcc/rust/expand/rust-macro-builtins.cc
@@ -66,7 +66,7 @@ macro_end_token (AST::DelimTokenTree &invoc_token_tree,
 
 /* Expand and extract an expression from the macro */
 
-static inline AST::ASTFragment
+static inline AST::Fragment
 try_expand_macro_expression (AST::Expr *expr, MacroExpander *expander)
 {
   rust_assert (expander);
@@ -264,25 +264,25 @@ load_file_bytes (const char *filename)
 }
 } // namespace
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::assert (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   rust_debug ("assert!() called");
 
-  return AST::ASTFragment::create_error ();
+  return AST::Fragment::create_error ();
 }
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::file (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   auto current_file
     = Session::get_instance ().linemap->location_file (invoc_locus);
   auto file_str = AST::SingleASTNode (make_string (invoc_locus, current_file));
 
-  return AST::ASTFragment ({file_str});
+  return AST::Fragment ({file_str});
 }
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::column (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   auto current_column
@@ -292,14 +292,14 @@ MacroBuiltin::column (Location invoc_locus, AST::MacroInvocData &invoc)
     new AST::LiteralExpr (std::to_string (current_column), AST::Literal::INT,
 			  PrimitiveCoreType::CORETYPE_U32, {}, invoc_locus)));
 
-  return AST::ASTFragment ({column_no});
+  return AST::Fragment ({column_no});
 }
 
 /* Expand builtin macro include_bytes!("filename"), which includes the contents
    of the given file as reference to a byte array. Yields an expression of type
    &'static [u8; N].  */
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::include_bytes (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   /* Get target filename from the macro invocation, which is treated as a path
@@ -308,7 +308,7 @@ MacroBuiltin::include_bytes (Location invoc_locus, AST::MacroInvocData &invoc)
     = parse_single_string_literal (invoc.get_delim_tok_tree (), invoc_locus,
 				   invoc.get_expander ());
   if (lit_expr == nullptr)
-    return AST::ASTFragment::create_error ();
+    return AST::Fragment::create_error ();
 
   std::string target_filename
     = source_relative_path (lit_expr->as_string (), invoc_locus);
@@ -335,14 +335,14 @@ MacroBuiltin::include_bytes (Location invoc_locus, AST::MacroInvocData &invoc)
     new AST::BorrowExpr (std::move (array), false, false, {}, invoc_locus));
 
   auto node = AST::SingleASTNode (std::move (borrow));
-  return AST::ASTFragment ({node});
+  return AST::Fragment ({node});
 }
 
 /* Expand builtin macro include_str!("filename"), which includes the contents
    of the given file as a string. The file must be UTF-8 encoded. Yields an
    expression of type &'static str.  */
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::include_str (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   /* Get target filename from the macro invocation, which is treated as a path
@@ -351,7 +351,7 @@ MacroBuiltin::include_str (Location invoc_locus, AST::MacroInvocData &invoc)
     = parse_single_string_literal (invoc.get_delim_tok_tree (), invoc_locus,
 				   invoc.get_expander ());
   if (lit_expr == nullptr)
-    return AST::ASTFragment::create_error ();
+    return AST::Fragment::create_error ();
 
   std::string target_filename
     = source_relative_path (lit_expr->as_string (), invoc_locus);
@@ -362,30 +362,30 @@ MacroBuiltin::include_str (Location invoc_locus, AST::MacroInvocData &invoc)
   std::string str ((const char *) &bytes[0], bytes.size ());
 
   auto node = AST::SingleASTNode (make_string (invoc_locus, str));
-  return AST::ASTFragment ({node});
+  return AST::Fragment ({node});
 }
 
 /* Expand builtin macro compile_error!("error"), which forces a compile error
    during the compile time. */
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::compile_error (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   auto lit_expr
     = parse_single_string_literal (invoc.get_delim_tok_tree (), invoc_locus,
 				   invoc.get_expander ());
   if (lit_expr == nullptr)
-    return AST::ASTFragment::create_error ();
+    return AST::Fragment::create_error ();
 
   std::string error_string = lit_expr->as_string ();
   rust_error_at (invoc_locus, "%s", error_string.c_str ());
 
-  return AST::ASTFragment::create_error ();
+  return AST::Fragment::create_error ();
 }
 
 /* Expand builtin macro concat!(), which joins all the literal parameters
    into a string with no delimiter. */
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::concat (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   auto invoc_token_tree = invoc.get_delim_tok_tree ();
@@ -427,16 +427,16 @@ MacroBuiltin::concat (Location invoc_locus, AST::MacroInvocData &invoc)
   parser.skip_token (last_token_id);
 
   if (has_error)
-    return AST::ASTFragment::create_error ();
+    return AST::Fragment::create_error ();
 
   auto node = AST::SingleASTNode (make_string (invoc_locus, str));
-  return AST::ASTFragment ({node});
+  return AST::Fragment ({node});
 }
 
 /* Expand builtin macro env!(), which inspects an environment variable at
    compile time. */
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::env (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   auto invoc_token_tree = invoc.get_delim_tok_tree ();
@@ -451,11 +451,11 @@ MacroBuiltin::env (Location invoc_locus, AST::MacroInvocData &invoc)
   auto expanded_expr = try_expand_many_expr (parser, invoc_locus, last_token_id,
 					     invoc.get_expander (), has_error);
   if (has_error)
-    return AST::ASTFragment::create_error ();
+    return AST::Fragment::create_error ();
   if (expanded_expr.size () < 1 || expanded_expr.size () > 2)
     {
       rust_error_at (invoc_locus, "env! takes 1 or 2 arguments");
-      return AST::ASTFragment::create_error ();
+      return AST::Fragment::create_error ();
     }
   if (expanded_expr.size () > 0)
     {
@@ -463,7 +463,7 @@ MacroBuiltin::env (Location invoc_locus, AST::MacroInvocData &invoc)
 	    = try_extract_string_literal_from_fragment (invoc_locus,
 							expanded_expr[0])))
 	{
-	  return AST::ASTFragment::create_error ();
+	  return AST::Fragment::create_error ();
 	}
     }
   if (expanded_expr.size () > 1)
@@ -472,7 +472,7 @@ MacroBuiltin::env (Location invoc_locus, AST::MacroInvocData &invoc)
 	    = try_extract_string_literal_from_fragment (invoc_locus,
 							expanded_expr[1])))
 	{
-	  return AST::ASTFragment::create_error ();
+	  return AST::Fragment::create_error ();
 	}
     }
 
@@ -487,14 +487,14 @@ MacroBuiltin::env (Location invoc_locus, AST::MacroInvocData &invoc)
 		       lit_expr->as_string ().c_str ());
       else
 	rust_error_at (invoc_locus, "%s", error_expr->as_string ().c_str ());
-      return AST::ASTFragment::create_error ();
+      return AST::Fragment::create_error ();
     }
 
   auto node = AST::SingleASTNode (make_string (invoc_locus, env_value));
-  return AST::ASTFragment ({node});
+  return AST::Fragment ({node});
 }
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::cfg (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   // only parse if not already parsed
@@ -519,7 +519,7 @@ MacroBuiltin::cfg (Location invoc_locus, AST::MacroInvocData &invoc)
   /* TODO: assuming that cfg! macros can only have one meta item inner, like cfg
    * attributes */
   if (invoc.get_meta_items ().size () != 1)
-    return AST::ASTFragment::create_error ();
+    return AST::Fragment::create_error ();
 
   bool result = invoc.get_meta_items ()[0]->check_cfg_predicate (
     Session::get_instance ());
@@ -527,13 +527,13 @@ MacroBuiltin::cfg (Location invoc_locus, AST::MacroInvocData &invoc)
     new AST::LiteralExpr (result ? "true" : "false", AST::Literal::BOOL,
 			  PrimitiveCoreType::CORETYPE_BOOL, {}, invoc_locus)));
 
-  return AST::ASTFragment ({literal_exp});
+  return AST::Fragment ({literal_exp});
 }
 
 /* Expand builtin macro include!(), which includes a source file at the current
  scope compile time. */
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::include (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   /* Get target filename from the macro invocation, which is treated as a path
@@ -542,7 +542,7 @@ MacroBuiltin::include (Location invoc_locus, AST::MacroInvocData &invoc)
     = parse_single_string_literal (invoc.get_delim_tok_tree (), invoc_locus,
 				   invoc.get_expander ());
   if (lit_expr == nullptr)
-    return AST::ASTFragment::create_error ();
+    return AST::Fragment::create_error ();
 
   std::string filename
     = source_relative_path (lit_expr->as_string (), invoc_locus);
@@ -556,7 +556,7 @@ MacroBuiltin::include (Location invoc_locus, AST::MacroInvocData &invoc)
     {
       rust_error_at (lit_expr->get_locus (),
 		     "cannot open included file %qs: %m", target_filename);
-      return AST::ASTFragment::create_error ();
+      return AST::Fragment::create_error ();
     }
 
   rust_debug ("Attempting to parse included file %s", target_filename);
@@ -574,7 +574,7 @@ MacroBuiltin::include (Location invoc_locus, AST::MacroInvocData &invoc)
     {
       // inform the user that the errors above are from a included file
       rust_inform (invoc_locus, "included from here");
-      return AST::ASTFragment::create_error ();
+      return AST::Fragment::create_error ();
     }
 
   std::vector<AST::SingleASTNode> nodes{};
@@ -584,10 +584,10 @@ MacroBuiltin::include (Location invoc_locus, AST::MacroInvocData &invoc)
       nodes.push_back (node);
     }
 
-  return AST::ASTFragment (nodes);
+  return AST::Fragment (nodes);
 }
 
-AST::ASTFragment
+AST::Fragment
 MacroBuiltin::line (Location invoc_locus, AST::MacroInvocData &invoc)
 {
   auto current_line
@@ -597,7 +597,7 @@ MacroBuiltin::line (Location invoc_locus, AST::MacroInvocData &invoc)
     new AST::LiteralExpr (std::to_string (current_line), AST::Literal::INT,
 			  PrimitiveCoreType::CORETYPE_U32, {}, invoc_locus)));
 
-  return AST::ASTFragment ({line_no});
+  return AST::Fragment ({line_no});
 }
 
 } // namespace Rust
diff --git a/gcc/rust/expand/rust-macro-builtins.h b/gcc/rust/expand/rust-macro-builtins.h
index f1ea545ed21..c65bd940189 100644
--- a/gcc/rust/expand/rust-macro-builtins.h
+++ b/gcc/rust/expand/rust-macro-builtins.h
@@ -20,6 +20,7 @@
 #define RUST_MACRO_BUILTINS_H
 
 #include "rust-ast.h"
+#include "rust-ast-fragment.h"
 #include "rust-location.h"
 
 /**
@@ -61,6 +62,7 @@
 
 /* If assert is defined as a macro this file will not parse, so undefine this
    before continuing.  */
+// TODO: Rename all functions here `*_handler`
 #ifdef assert
 #undef assert
 #endif
@@ -69,38 +71,34 @@ namespace Rust {
 class MacroBuiltin
 {
 public:
-  static AST::ASTFragment assert (Location invoc_locus,
-				  AST::MacroInvocData &invoc);
-
-  static AST::ASTFragment file (Location invoc_locus,
-				AST::MacroInvocData &invoc);
+  static AST::Fragment assert (Location invoc_locus,
+			       AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment column (Location invoc_locus,
-				  AST::MacroInvocData &invoc);
+  static AST::Fragment file (Location invoc_locus, AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment include_bytes (Location invoc_locus,
-					 AST::MacroInvocData &invoc);
+  static AST::Fragment column (Location invoc_locus,
+			       AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment include_str (Location invoc_locus,
-				       AST::MacroInvocData &invoc);
+  static AST::Fragment include_bytes (Location invoc_locus,
+				      AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment compile_error (Location invoc_locus,
-					 AST::MacroInvocData &invoc);
+  static AST::Fragment include_str (Location invoc_locus,
+				    AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment concat (Location invoc_locus,
-				  AST::MacroInvocData &invoc);
+  static AST::Fragment compile_error (Location invoc_locus,
+				      AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment env (Location invoc_locus,
+  static AST::Fragment concat (Location invoc_locus,
 			       AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment cfg (Location invoc_locus,
-			       AST::MacroInvocData &invoc);
+  static AST::Fragment env (Location invoc_locus, AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment include (Location invoc_locus,
-				   AST::MacroInvocData &invoc);
+  static AST::Fragment cfg (Location invoc_locus, AST::MacroInvocData &invoc);
 
-  static AST::ASTFragment line (Location invoc_locus,
+  static AST::Fragment include (Location invoc_locus,
 				AST::MacroInvocData &invoc);
+
+  static AST::Fragment line (Location invoc_locus, AST::MacroInvocData &invoc);
 };
 } // namespace Rust
 
diff --git a/gcc/rust/expand/rust-macro-expand.cc b/gcc/rust/expand/rust-macro-expand.cc
index d94cd118700..0684a28787f 100644
--- a/gcc/rust/expand/rust-macro-expand.cc
+++ b/gcc/rust/expand/rust-macro-expand.cc
@@ -26,7 +26,7 @@
 #include "rust-early-name-resolver.h"
 
 namespace Rust {
-AST::ASTFragment
+AST::Fragment
 MacroExpander::expand_decl_macro (Location invoc_locus,
 				  AST::MacroInvocData &invoc,
 				  AST::MacroRulesDefinition &rules_def,
@@ -103,7 +103,7 @@ MacroExpander::expand_decl_macro (Location invoc_locus,
       RichLocation r (invoc_locus);
       r.add_range (rules_def.get_locus ());
       rust_error_at (r, "Failed to match any rule within macro");
-      return AST::ASTFragment::create_error ();
+      return AST::Fragment::create_error ();
     }
 
   return transcribe_rule (*matched_rule, invoc_token_tree, matched_fragments,
@@ -139,7 +139,7 @@ MacroExpander::expand_invoc (AST::MacroInvocation &invoc, bool has_semicolon)
   //      - else is unreachable
   //  - derive container macro - unreachable
 
-  auto fragment = AST::ASTFragment::create_error ();
+  auto fragment = AST::Fragment::create_error ();
   invoc_data.set_expander (this);
 
   // lookup the rules
@@ -707,7 +707,7 @@ MacroExpander::match_repetition (Parser<MacroInvocLexer> &parser,
 /**
  * Helper function to refactor calling a parsing function 0 or more times
  */
-static AST::ASTFragment
+static AST::Fragment
 parse_many (Parser<MacroInvocLexer> &parser, TokenId &delimiter,
 	    std::function<AST::SingleASTNode ()> parse_fn)
 {
@@ -723,13 +723,13 @@ parse_many (Parser<MacroInvocLexer> &parser, TokenId &delimiter,
 	  for (auto err : parser.get_errors ())
 	    err.emit_error ();
 
-	  return AST::ASTFragment::create_error ();
+	  return AST::Fragment::create_error ();
 	}
 
       nodes.emplace_back (std::move (node));
     }
 
-  return AST::ASTFragment (std::move (nodes));
+  return AST::Fragment (std::move (nodes));
 }
 
 /**
@@ -738,7 +738,7 @@ parse_many (Parser<MacroInvocLexer> &parser, TokenId &delimiter,
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_items (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
 {
   return parse_many (parser, delimiter, [&parser] () {
@@ -753,7 +753,7 @@ transcribe_many_items (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_ext (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
 {
   return parse_many (parser, delimiter, [&parser] () {
@@ -768,7 +768,7 @@ transcribe_many_ext (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_trait_items (Parser<MacroInvocLexer> &parser,
 			     TokenId &delimiter)
 {
@@ -784,7 +784,7 @@ transcribe_many_trait_items (Parser<MacroInvocLexer> &parser,
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_impl_items (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
 {
   return parse_many (parser, delimiter, [&parser] () {
@@ -799,7 +799,7 @@ transcribe_many_impl_items (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_trait_impl_items (Parser<MacroInvocLexer> &parser,
 				  TokenId &delimiter)
 {
@@ -815,7 +815,7 @@ transcribe_many_trait_impl_items (Parser<MacroInvocLexer> &parser,
  * @param parser Parser to extract statements from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_stmts (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
 {
   auto restrictions = ParseRestrictions ();
@@ -835,12 +835,12 @@ transcribe_many_stmts (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
  *
  * @param parser Parser to extract statements from
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_expression (Parser<MacroInvocLexer> &parser)
 {
   auto expr = parser.parse_expr ();
 
-  return AST::ASTFragment ({std::move (expr)});
+  return AST::Fragment ({std::move (expr)});
 }
 
 /**
@@ -848,17 +848,17 @@ transcribe_expression (Parser<MacroInvocLexer> &parser)
  *
  * @param parser Parser to extract statements from
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_type (Parser<MacroInvocLexer> &parser)
 {
   auto type = parser.parse_type (true);
   for (auto err : parser.get_errors ())
     err.emit_error ();
 
-  return AST::ASTFragment ({std::move (type)});
+  return AST::Fragment ({std::move (type)});
 }
 
-static AST::ASTFragment
+static AST::Fragment
 transcribe_on_delimiter (Parser<MacroInvocLexer> &parser, bool semicolon,
 			 AST::DelimType delimiter, TokenId last_token_id)
 {
@@ -868,7 +868,7 @@ transcribe_on_delimiter (Parser<MacroInvocLexer> &parser, bool semicolon,
     return transcribe_expression (parser);
 } // namespace Rust
 
-static AST::ASTFragment
+static AST::Fragment
 transcribe_context (MacroExpander::ContextType ctx,
 		    Parser<MacroInvocLexer> &parser, bool semicolon,
 		    AST::DelimType delimiter, TokenId last_token_id)
@@ -929,7 +929,7 @@ tokens_to_str (std::vector<std::unique_ptr<AST::Token>> &tokens)
   return str;
 }
 
-AST::ASTFragment
+AST::Fragment
 MacroExpander::transcribe_rule (
   AST::MacroRule &match_rule, AST::DelimTokenTree &invoc_token_tree,
   std::map<std::string, MatchedFragmentContainer> &matched_fragments,
@@ -951,7 +951,7 @@ MacroExpander::transcribe_rule (
   rust_debug ("substituted tokens: %s",
 	      tokens_to_str (substituted_tokens).c_str ());
 
-  // parse it to an ASTFragment
+  // parse it to an Fragment
   MacroInvocLexer lex (std::move (substituted_tokens));
   Parser<MacroInvocLexer> parser (lex);
 
@@ -994,7 +994,7 @@ MacroExpander::transcribe_rule (
     {
       for (auto &err : parser.get_errors ())
 	rust_error_at (err.locus, "%s", err.message.c_str ());
-      return AST::ASTFragment::create_error ();
+      return AST::Fragment::create_error ();
     }
 
   // are all the tokens used?
diff --git a/gcc/rust/expand/rust-macro-expand.h b/gcc/rust/expand/rust-macro-expand.h
index 187d79f9a28..b0c0c23a0c3 100644
--- a/gcc/rust/expand/rust-macro-expand.h
+++ b/gcc/rust/expand/rust-macro-expand.h
@@ -230,7 +230,7 @@ struct MacroExpander
   MacroExpander (AST::Crate &crate, ExpansionCfg cfg, Session &session)
     : cfg (cfg), crate (crate), session (session),
       sub_stack (SubstitutionScope ()),
-      expanded_fragment (AST::ASTFragment::create_error ()),
+      expanded_fragment (AST::Fragment::create_error ()),
       resolver (Resolver::Resolver::get ()),
       mappings (Analysis::Mappings::get ())
   {}
@@ -246,10 +246,9 @@ struct MacroExpander
   void expand_invoc (AST::MacroInvocation &invoc, bool has_semicolon);
 
   // Expands a single declarative macro.
-  AST::ASTFragment expand_decl_macro (Location locus,
-				      AST::MacroInvocData &invoc,
-				      AST::MacroRulesDefinition &rules_def,
-				      bool semicolon);
+  AST::Fragment expand_decl_macro (Location locus, AST::MacroInvocData &invoc,
+				   AST::MacroRulesDefinition &rules_def,
+				   bool semicolon);
 
   void expand_cfg_attrs (AST::AttrVec &attrs);
   bool fails_cfg (const AST::AttrVec &attr) const;
@@ -260,7 +259,7 @@ struct MacroExpander
   bool try_match_rule (AST::MacroRule &match_rule,
 		       AST::DelimTokenTree &invoc_token_tree);
 
-  AST::ASTFragment transcribe_rule (
+  AST::Fragment transcribe_rule (
     AST::MacroRule &match_rule, AST::DelimTokenTree &invoc_token_tree,
     std::map<std::string, MatchedFragmentContainer> &matched_fragments,
     bool semicolon, ContextType ctx);
@@ -314,16 +313,16 @@ struct MacroExpander
 
   ContextType peek_context () { return context.back (); }
 
-  void set_expanded_fragment (AST::ASTFragment &&fragment)
+  void set_expanded_fragment (AST::Fragment &&fragment)
   {
     expanded_fragment = std::move (fragment);
   }
 
-  AST::ASTFragment take_expanded_fragment (AST::ASTVisitor &vis)
+  AST::Fragment take_expanded_fragment (AST::ASTVisitor &vis)
   {
-    AST::ASTFragment old_fragment = std::move (expanded_fragment);
+    AST::Fragment old_fragment = std::move (expanded_fragment);
     auto accumulator = std::vector<AST::SingleASTNode> ();
-    expanded_fragment = AST::ASTFragment::create_error ();
+    expanded_fragment = AST::Fragment::create_error ();
     auto early_name_resolver = Resolver::EarlyNameResolver ();
 
     for (auto &node : old_fragment.get_nodes ())
@@ -345,7 +344,7 @@ struct MacroExpander
 	    auto new_nodes = expanded_fragment.get_nodes ();
 	    std::move (new_nodes.begin (), new_nodes.end (),
 		       std::back_inserter (accumulator));
-	    expanded_fragment = AST::ASTFragment (accumulator);
+	    expanded_fragment = AST::Fragment (accumulator);
 	  }
 	expansion_depth--;
       }
@@ -358,7 +357,7 @@ private:
   Session &session;
   SubstitutionScope sub_stack;
   std::vector<ContextType> context;
-  AST::ASTFragment expanded_fragment;
+  AST::Fragment expanded_fragment;
 
 public:
   Resolver::Resolver *resolver;
diff --git a/gcc/rust/util/rust-hir-map.cc b/gcc/rust/util/rust-hir-map.cc
index 4aeb7f5ae18..bee0682e9b4 100644
--- a/gcc/rust/util/rust-hir-map.cc
+++ b/gcc/rust/util/rust-hir-map.cc
@@ -840,8 +840,8 @@ Mappings::iterate_trait_items (
 void
 Mappings::insert_macro_def (AST::MacroRulesDefinition *macro)
 {
-  static std::map<std::string, std::function<AST::ASTFragment (
-				 Location, AST::MacroInvocData &)>>
+  static std::map<
+    std::string, std::function<AST::Fragment (Location, AST::MacroInvocData &)>>
     builtin_macros = {
       {"assert", MacroBuiltin::assert},
       {"file", MacroBuiltin::file},
-- 
2.39.1