Merge #1607

1607: Improve AST Fragment class r=CohenArthur a=CohenArthur

This changes the APIs around creating AST fragments and refactors the class into its own header and source file, hopefully making it easier to use. This will also help creating "unexpanded" AST fragments for proper builtin macro expansion with the new fixed-point algorithm introduced by #1606 

`@liushuyu` pinging you since you've worked extensively with the macro system. Would love your review!

Co-authored-by: Arthur Cohen <arthur.cohen@embecosm.com>

1 files changed, 36 insertions, 36 deletions

diff --git a/gcc/rust/expand/rust-macro-builtins.cc b/gcc/rust/expand/rust-macro-builtins.cc
index 706b5d4..14322d0 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::complete ({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::complete ({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::complete ({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::complete ({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::complete ({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::complete ({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::complete ({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::complete (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::complete ({line_no});
 }
 
 } // namespace Rust