Remove `tokenstream::Delimited`.

Because it's an extra type layer that doesn't really help; in a couple
of places it actively gets in the way, and overall removing it makes the
code nicer. It does, however, move `tokenstream::TokenTree` further away
from the `TokenTree` in `quote.rs`.

More importantly, this change reduces the size of `TokenStream` from 48
bytes to 40 bytes on x86-64, which is enough to slightly reduce
instruction counts on numerous benchmarks, the best by 1.5%.

Note that `open_tt` and `close_tt` have gone from being methods on
`Delimited` to associated methods of `TokenTree`.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index e50f28897dd..41165c7e36d 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -815,12 +815,12 @@ pub trait PrintState<'a> {
                     _ => Ok(())
                 }
             }
-            TokenTree::Delimited(_, ref delimed) => {
-                self.writer().word(token_to_string(&delimed.open_token()))?;
+            TokenTree::Delimited(_, delim, tts) => {
+                self.writer().word(token_to_string(&token::OpenDelim(delim)))?;
                 self.writer().space()?;
-                self.print_tts(delimed.stream())?;
+                self.print_tts(tts.stream())?;
                 self.writer().space()?;
-                self.writer().word(token_to_string(&delimed.close_token()))
+                self.writer().word(token_to_string(&token::CloseDelim(delim)))
             },
         }
     }