Auto merge of #60910 - nnethercote:avoid-some-unnecessary-interning, r=petrochenkov

Avoid some unnecessary interning

r? @petrochenkov

6 files changed, 22 insertions, 18 deletions

diff --git a/src/libsyntax/attr/mod.rs b/src/libsyntax/attr/mod.rs
index d94a3165b0f..592b40df176 100644
--- a/src/libsyntax/attr/mod.rs
+++ b/src/libsyntax/attr/mod.rs
@@ -22,7 +22,7 @@ use crate::parse::parser::Parser;
 use crate::parse::{self, ParseSess, PResult};
 use crate::parse::token::{self, Token};
 use crate::ptr::P;
-use crate::symbol::{keywords, Symbol};
+use crate::symbol::{keywords, Symbol, sym};
 use crate::ThinVec;
 use crate::tokenstream::{TokenStream, TokenTree, DelimSpan};
 use crate::GLOBALS;
@@ -323,7 +323,7 @@ impl Attribute {
         if self.is_sugared_doc {
             let comment = self.value_str().unwrap();
             let meta = mk_name_value_item_str(
-                Ident::from_str("doc"),
+                Ident::with_empty_ctxt(sym::doc),
                 dummy_spanned(Symbol::intern(&strip_doc_comment_decoration(&comment.as_str()))));
             let mut attr = if self.style == ast::AttrStyle::Outer {
                 mk_attr_outer(self.span, self.id, meta)
@@ -414,7 +414,7 @@ pub fn mk_sugared_doc_attr(id: AttrId, text: Symbol, span: Span) -> Attribute {
     Attribute {
         id,
         style,
-        path: Path::from_ident(Ident::from_str("doc").with_span_pos(span)),
+        path: Path::from_ident(Ident::with_empty_ctxt(sym::doc).with_span_pos(span)),
         tokens: MetaItemKind::NameValue(lit).tokens(span),
         is_sugared_doc: true,
         span,
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index a286fd83e3c..019ebc8566f 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -1522,19 +1522,19 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
                             let include_info = vec![
                                 ast::NestedMetaItem::MetaItem(
                                     attr::mk_name_value_item_str(
-                                        Ident::from_str("file"),
+                                        Ident::with_empty_ctxt(sym::file),
                                         dummy_spanned(file),
                                     ),
                                 ),
                                 ast::NestedMetaItem::MetaItem(
                                     attr::mk_name_value_item_str(
-                                        Ident::from_str("contents"),
+                                        Ident::with_empty_ctxt(sym::contents),
                                         dummy_spanned(src_interned),
                                     ),
                                 ),
                             ];
 
-                            let include_ident = Ident::from_str("include");
+                            let include_ident = Ident::with_empty_ctxt(sym::include);
                             let item = attr::mk_list_item(DUMMY_SP, include_ident, include_info);
                             items.push(ast::NestedMetaItem::MetaItem(item));
                         }
@@ -1600,7 +1600,7 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
                 }
             }
 
-            let meta = attr::mk_list_item(DUMMY_SP, Ident::from_str("doc"), items);
+            let meta = attr::mk_list_item(DUMMY_SP, Ident::with_empty_ctxt(sym::doc), items);
             match at.style {
                 ast::AttrStyle::Inner => *at = attr::mk_spanned_attr_inner(at.span, at.id, meta),
                 ast::AttrStyle::Outer => *at = attr::mk_spanned_attr_outer(at.span, at.id, meta),
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 3d55267b8e8..24d120376de 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -352,7 +352,7 @@ impl TokenCursor {
         let body = TokenTree::Delimited(
             delim_span,
             token::Bracket,
-            [TokenTree::Token(sp, token::Ident(ast::Ident::from_str("doc"), false)),
+            [TokenTree::Token(sp, token::Ident(ast::Ident::with_empty_ctxt(sym::doc), false)),
              TokenTree::Token(sp, token::Eq),
              TokenTree::Token(sp, token::Literal(
                 token::StrRaw(Symbol::intern(&stripped), num_of_hashes), None))
@@ -7011,7 +7011,8 @@ impl<'a> Parser<'a> {
                     let attr = Attribute {
                         id: attr::mk_attr_id(),
                         style: ast::AttrStyle::Outer,
-                        path: ast::Path::from_ident(Ident::from_str("warn_directory_ownership")),
+                        path: ast::Path::from_ident(
+                            Ident::with_empty_ctxt(sym::warn_directory_ownership)),
                         tokens: TokenStream::empty(),
                         is_sugared_doc: false,
                         span: syntax_pos::DUMMY_SP,
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 86db7a673d4..cd86d94f4b8 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -13,7 +13,7 @@ use crate::print::pp::{self, Breaks};
 use crate::print::pp::Breaks::{Consistent, Inconsistent};
 use crate::ptr::P;
 use crate::std_inject;
-use crate::symbol::keywords;
+use crate::symbol::{keywords, sym};
 use crate::tokenstream::{self, TokenStream, TokenTree};
 
 use rustc_target::spec::abi::{self, Abi};
@@ -89,13 +89,14 @@ pub fn print_crate<'a>(cm: &'a SourceMap,
         // of the feature gate, so we fake them up here.
 
         // #![feature(prelude_import)]
-        let pi_nested = attr::mk_nested_word_item(ast::Ident::from_str("prelude_import"));
-        let list = attr::mk_list_item(DUMMY_SP, ast::Ident::from_str("feature"), vec![pi_nested]);
+        let pi_nested = attr::mk_nested_word_item(ast::Ident::with_empty_ctxt(sym::prelude_import));
+        let list = attr::mk_list_item(
+            DUMMY_SP, ast::Ident::with_empty_ctxt(sym::feature), vec![pi_nested]);
         let fake_attr = attr::mk_attr_inner(DUMMY_SP, attr::mk_attr_id(), list);
         s.print_attribute(&fake_attr)?;
 
         // #![no_std]
-        let no_std_meta = attr::mk_word_item(ast::Ident::from_str("no_std"));
+        let no_std_meta = attr::mk_word_item(ast::Ident::with_empty_ctxt(sym::no_std));
         let fake_attr = attr::mk_attr_inner(DUMMY_SP, attr::mk_attr_id(), no_std_meta);
         s.print_attribute(&fake_attr)?;
     }
diff --git a/src/libsyntax/std_inject.rs b/src/libsyntax/std_inject.rs
index f08fdcc6fb5..6784a2abe55 100644
--- a/src/libsyntax/std_inject.rs
+++ b/src/libsyntax/std_inject.rs
@@ -77,9 +77,11 @@ pub fn maybe_inject_crates_ref(
             None
         };
         krate.module.items.insert(0, P(ast::Item {
-            attrs: vec![attr::mk_attr_outer(DUMMY_SP,
-                                            attr::mk_attr_id(),
-                                            attr::mk_word_item(ast::Ident::from_str("macro_use")))],
+            attrs: vec![attr::mk_attr_outer(
+                DUMMY_SP,
+                attr::mk_attr_id(),
+                attr::mk_word_item(ast::Ident::with_empty_ctxt(sym::macro_use))
+            )],
             vis: dummy_spanned(ast::VisibilityKind::Inherited),
             node: ast::ItemKind::ExternCrate(alt_std_name.or(orig_name)),
             ident: ast::Ident::with_empty_ctxt(rename),
diff --git a/src/libsyntax/test.rs b/src/libsyntax/test.rs
index 21bc236d00e..3fd0790161c 100644
--- a/src/libsyntax/test.rs
+++ b/src/libsyntax/test.rs
@@ -171,7 +171,7 @@ impl MutVisitor for EntryPointCleaner {
             EntryPointType::MainAttr |
             EntryPointType::Start =>
                 item.map(|ast::Item {id, ident, attrs, node, vis, span, tokens}| {
-                    let allow_ident = Ident::from_str("allow");
+                    let allow_ident = Ident::with_empty_ctxt(sym::allow);
                     let dc_nested = attr::mk_nested_word_item(Ident::from_str("dead_code"));
                     let allow_dead_code_item = attr::mk_list_item(DUMMY_SP, allow_ident,
                                                                   vec![dc_nested]);
@@ -215,7 +215,7 @@ fn mk_reexport_mod(cx: &mut TestCtxt<'_>,
                    tests: Vec<Ident>,
                    tested_submods: Vec<(Ident, Ident)>)
                    -> (P<ast::Item>, Ident) {
-    let super_ = Ident::from_str("super");
+    let super_ = Ident::with_empty_ctxt(keywords::Super.name());
 
     let items = tests.into_iter().map(|r| {
         cx.ext_cx.item_use_simple(DUMMY_SP, dummy_spanned(ast::VisibilityKind::Public),