mbe::TokenTree: remove Lrc around Delimited and SequenceRepetition.

Author: nnethercote

compiler/rustc_expand/src/mbe.rs

@@ -13,7 +13,6 @@ crate mod transcribe;
 use metavar_expr::MetaVarExpr;
 use rustc_ast::token::{self, NonterminalKind, Token, TokenKind};
 use rustc_ast::tokenstream::DelimSpan;
-use rustc_data_structures::sync::Lrc;
 use rustc_span::symbol::Ident;
 use rustc_span::Span;
 
@@ -64,13 +63,13 @@ enum KleeneOp {
 
 /// Similar to `tokenstream::TokenTree`, except that `Sequence`, `MetaVar`, `MetaVarDecl`, and
 /// `MetaVarExpr` are "first-class" token trees. Useful for parsing macros.
-#[derive(Debug, Clone, PartialEq, Encodable, Decodable)]
+#[derive(Debug, PartialEq, Encodable, Decodable)]
 enum TokenTree {
     Token(Token),
     /// A delimited sequence, e.g. `($e:expr)` (RHS) or `{ $e }` (LHS).
-    Delimited(DelimSpan, Lrc<Delimited>),
+    Delimited(DelimSpan, Delimited),
     /// A kleene-style repetition sequence, e.g. `$($e:expr)*` (RHS) or `$($e),*` (LHS).
-    Sequence(DelimSpan, Lrc<SequenceRepetition>),
+    Sequence(DelimSpan, SequenceRepetition),
     /// e.g., `$var`.
     MetaVar(Span, Ident),
     /// e.g., `$var:expr`. Only appears on the LHS.

compiler/rustc_expand/src/mbe/macro_rules.rs

@@ -14,7 +14,6 @@ use rustc_ast::{NodeId, DUMMY_NODE_ID};
 use rustc_ast_pretty::pprust;
 use rustc_attr::{self as attr, TransparencyError};
 use rustc_data_structures::fx::FxHashMap;
-use rustc_data_structures::sync::Lrc;
 use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder};
 use rustc_feature::Features;
 use rustc_lint_defs::builtin::{
@@ -407,7 +406,7 @@ pub fn compile_declarative_macro(
     let argument_gram = vec![
         mbe::TokenTree::Sequence(
             DelimSpan::dummy(),
-            Lrc::new(mbe::SequenceRepetition {
+            mbe::SequenceRepetition {
                 tts: vec![
                     mbe::TokenTree::MetaVarDecl(def.span, lhs_nm, tt_spec),
                     mbe::TokenTree::token(token::FatArrow, def.span),
@@ -419,20 +418,20 @@ pub fn compile_declarative_macro(
                 )),
                 kleene: mbe::KleeneToken::new(mbe::KleeneOp::OneOrMore, def.span),
                 num_captures: 2,
-            }),
+            },
         ),
         // to phase into semicolon-termination instead of semicolon-separation
         mbe::TokenTree::Sequence(
             DelimSpan::dummy(),
-            Lrc::new(mbe::SequenceRepetition {
+            mbe::SequenceRepetition {
                 tts: vec![mbe::TokenTree::token(
                     if macro_rules { token::Semi } else { token::Comma },
                     def.span,
                 )],
                 separator: None,
                 kleene: mbe::KleeneToken::new(mbe::KleeneOp::ZeroOrMore, def.span),
                 num_captures: 0,
-            }),
+            },
         ),
     ];
     // Convert it into `MatcherLoc` form.

compiler/rustc_expand/src/mbe/quoted.rs

@@ -11,8 +11,6 @@ use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::edition::Edition;
 use rustc_span::{Span, SyntaxContext};
 
-use rustc_data_structures::sync::Lrc;
-
 const VALID_FRAGMENT_NAMES_MSG: &str = "valid fragment specifiers are \
                                         `ident`, `block`, `stmt`, `expr`, `pat`, `ty`, `lifetime`, \
                                         `literal`, `path`, `meta`, `tt`, `item` and `vis`";
@@ -213,12 +211,7 @@ fn parse_tree(
                         if parsing_patterns { count_metavar_decls(&sequence) } else { 0 };
                     TokenTree::Sequence(
                         delim_span,
-                        Lrc::new(SequenceRepetition {
-                            tts: sequence,
-                            separator,
-                            kleene,
-                            num_captures,
-                        }),
+                        SequenceRepetition { tts: sequence, separator, kleene, num_captures },
                     )
                 }
 
@@ -269,10 +262,10 @@ fn parse_tree(
         // descend into the delimited set and further parse it.
         tokenstream::TokenTree::Delimited(span, delim, tts) => TokenTree::Delimited(
             span,
-            Lrc::new(Delimited {
+            Delimited {
                 delim,
                 tts: parse(tts, parsing_patterns, sess, node_id, features, edition),
-            }),
+            },
         ),
     }
 }